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Schafer R, LoGiudice JA, Hargwood P, Wilpers A. The Role of Midwives in US Perinatal Palliative Care: A Scoping Review. J Midwifery Womens Health 2024; 69:875-887. [PMID: 38979840 PMCID: PMC11622358 DOI: 10.1111/jmwh.13664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
INTRODUCTION Perinatal palliative care (PPC) is a rapidly growing and essential reproductive health care option for pregnant persons with a diagnosed life-limiting fetal condition who continue their pregnancy. The provision of PPC is within the scope of basic midwifery competencies, and midwives are well-positioned to make unique and valuable contributions to interprofessional PPC teams. However, little is known about midwives' past or current involvement in PPC in the United States. METHODS This scoping review of the literature investigated what is known about the role of midwives in PPC in the United States. Multiple databases of published literature were used for this review: PubMed, CINAHL, Embase, Web of Science, ProQuest, Google Scholar, and relevant citations from identified studies. All types of English language publications addressing midwives' involvement in PPC in the United States were included, without any limitations on publication date. RESULTS The role and contributions of midwives in PPC is not well represented in existing literature. Of the 259 results identified, 7 publications met criteria for inclusion. These included 5 case reports, one quantitative research article, and one conference abstract. Midwives are involved in PPC through the provision of direct clinical care (including antepartum, intrapartum, postpartum, neonatal, bereavement, postmortem, and follow-up care) and care planning and coordination as part of an interprofessional team. DISCUSSION Despite midwives being uniquely positioned to provide holistic, family-centered, and person-centered care in situations of pregnancy with life-limiting fetal conditions, there is limited literature about their involvement in PPC in the United States. PPC should be incorporated into midwifery education and training programs. Midwives should play a central role in shaping future research and policies to ensure the accessibility and quality of PPC.
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Schafer R, Bovbjerg ML, Cheyney M, Phillippi JC. Maternal and neonatal outcomes associated with breech presentation in planned community (home and birth center) births in the United States: A prospective observational cohort study. PLoS One 2024; 19:e0305587. [PMID: 39037977 PMCID: PMC11262641 DOI: 10.1371/journal.pone.0305587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 06/01/2024] [Indexed: 07/24/2024] Open
Abstract
OBJECTIVE Investigate maternal and neonatal outcomes associated with breech presentation in planned community births in the United States, including outcomes associated with types of breech presentation (i.e., frank, complete, footling/kneeling). DESIGN Secondary analysis of prospective cohort data from a national perinatal data registry (MANA Stats). SETTING Planned community birth (homes and birth centers), United States. SAMPLE Individuals with a term, singleton gestation (N = 71,943) planning community birth at labor onset. METHODS Descriptive statistics to calculate associations between types of breech presentation and maternal and neonatal outcomes. MAIN OUTCOME MEASURES Maternal: intrapartum/postpartum transfer, hospitalization, cesarean, hemorrhage, severe perineal laceration, duration of labor stages and membrane rupture Neonatal: transfer, hospitalization, NICU admission, congenital anomalies, umbilical cord prolapse, birth injury, intrapartum/neonatal death. RESULTS One percent (n = 695) of individuals experienced breech birth (n = 401, 57.6% vaginally). Most fetuses presented frank breech (57%), with 19% complete, 18% footling/kneeling, and 5% unknown type of breech presentation. Among all breech labors, there were high rates of intrapartum transfer and cesarean birth compared to cephalic presentation (OR 9.0, 95% CI 7.7-10.4 and OR 18.6, 95% CI 15.9-21.7, respectively), with no substantive difference based on parity, planned site of birth, or level of care integration into the health system. For all types of breech presentations, there was increased risk for nearly all assessed neonatal outcomes including hospital transfer, NICU admission, birth injury, and umbilical cord prolapse. Breech presentation was also associated with increased risk of intrapartum/neonatal death (OR 8.5, 95% CI 4.4-16.3), even after congenital anomalies were excluded. CONCLUSIONS All types of breech presentations in community birth settings are associated with increased risk of adverse neonatal outcomes. These research findings contribute to informed decision-making and reinforce the need for breech training and research and an increase in accessible, high-quality care for planned vaginal breech birth in US hospitals.
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Schafer R, Kennedy HP, Mulvaney S, Phillippi JC. Experience of decision-making for home breech birth: An interpretive description. SSM. QUALITATIVE RESEARCH IN HEALTH 2024; 5:100397. [PMID: 39534852 PMCID: PMC11556396 DOI: 10.1016/j.ssmqr.2024.100397] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2024]
Abstract
Despite research and recommendations supporting shared decision-making and vaginal birth as a reasonable option for appropriately screened candidates with a term breech pregnancy, cesarean remains the only mode of birth available in most hospitals in the United States. Unable to find care for planned vaginal birth in a hospital setting, some individuals choose to pursue breech birth at home, potentially placing themselves and their infants at increased risk. Through this analysis of qualitative data gathered from a mixed methods study, we explored the experience of decision-making of 25 individuals who left the US hospital system to pursue a home breech birth. Data were gathered through open-ended survey responses (n = 25) and subsequent in-depth, semi-structured interviews (n = 23) and analyzed using an interpretive description approach informed by situational analysis. Five interwoven and dynamic themes were identified in this complex decision-making process: valuing and trusting in normal birth, being "backed into a corner," asserting agency, making an informed choice, and drawing strength from the experience. This study provides a foundation for understanding the experience of decision-making and can inform future research and clinical practice to improve the provision of safe and respectful, person-centered care for breech pregnancy and birth.
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Schafer R, Dietrich MS, Kennedy HP, Mulvaney S, Phillippi JC. "I had no choice": A mixed-methods study on access to care for vaginal breech birth. Birth 2024; 51:413-423. [PMID: 37968839 DOI: 10.1111/birt.12797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/26/2023] [Accepted: 10/16/2023] [Indexed: 11/17/2023]
Abstract
INTRODUCTION Although current recommendations support vaginal breech birth as a reasonable option, access to breech birth in US hospitals is limited. This study explored the experiences of decision-making and perceptions of access to care in people who transferred out of the hospital system to pursue home breech birth. METHODS We conducted a mixed methods study of people with a singleton, term breech fetus who transferred out of the US hospital system to pursue home breech birth. Twenty-five people completed an online demographic and psychosocial survey, and 23 (92%) participated in semi-structured interviews. We used an interpretive description approach informed by situational analysis to analyze qualitative data about participants' experiences and perceived access to care. RESULTS Of 25 individuals who left the hospital system to pursue a home breech birth, most felt denied informed choice (64%) and threatened or coerced into cesarean (68%). The majority reported low or very low autonomy in decision-making (n = 20, 80%) and high decisional satisfaction using validated measures. Many participants felt safer in a hospital setting but were not able to access care for planned vaginal breech hospital birth, despite extensive efforts. Participants felt "backed into a corner" and "forced into homebirth," perceiving a lack of access to safe and respectful care in the hospital system. CONCLUSION Some service users believe that home birth is their only option when they cannot access hospital-based care for vaginal breech birth. Current barriers to care for breech birth limit birthing people's autonomy and may be placing them and their infants at increased risk.
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Basile-Ibrahim B, Combellick J, Mead TL, Sorensen A, Batten J, Schafer R. The Social Context of Pregnancy, Respectful Maternity Care, Biomarkers of Weathering, and Postpartum Mental Health Inequities: A Scoping Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2024; 21:480. [PMID: 38673391 PMCID: PMC11049830 DOI: 10.3390/ijerph21040480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/05/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024]
Abstract
Background: Mental health disorders are the number one cause of maternal mortality and a significant maternal morbidity. This scoping review sought to understand the associations between social context and experiences during pregnancy and birth, biological indicators of stress and weathering, and perinatal mood and anxiety disorders (PMADs). Methods: A scoping review was performed using PRISMA-ScR guidance and JBI scoping review methodology. The search was conducted in OVID Medline and Embase. Results: This review identified 74 eligible English-language peer-reviewed original research articles. A majority of studies reported significant associations between social context, negative and stressful experiences in the prenatal period, and a higher incidence of diagnosis and symptoms of PMADs. Included studies reported significant associations between postpartum depression and prenatal stressors (n = 17), socioeconomic disadvantage (n = 14), negative birth experiences (n = 9), obstetric violence (n = 3), and mistreatment by maternity care providers (n = 3). Birth-related post-traumatic stress disorder (PTSD) was positively associated with negative birth experiences (n = 11), obstetric violence (n = 1), mistreatment by the maternity care team (n = 1), socioeconomic disadvantage (n = 2), and prenatal stress (n = 1); and inverse association with supportiveness of the maternity care team (n = 5) and presence of a birth companion or doula (n = 4). Postpartum anxiety was significantly associated with negative birth experiences (n = 2) and prenatal stress (n = 3). Findings related to associations between biomarkers of stress and weathering, perinatal exposures, and PMADs (n = 14) had mixed significance. Conclusions: Postpartum mental health outcomes are linked with the prenatal social context and interactions with the maternity care team during pregnancy and birth. Respectful maternity care has the potential to reduce adverse postpartum mental health outcomes, especially for persons affected by systemic oppression.
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Aktan N, Blumenfeld J, Schafer R, Dorsen C, Nocella J. Urban Green Space and Perinatal Health Inequities in the United States: A Literature Review. J Perinat Educ 2024; 33:88-99. [PMID: 39399780 PMCID: PMC11467707 DOI: 10.1891/jpe-2023-0008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2024] Open
Abstract
Access to urban green space has been linked to positive health outcomes including enhanced perinatal health. The purpose of this article was to review, summarize, and synthesize what is known about the relationship between urban green space and perinatal health and outline implications for practice, policy, education, and research. Nineteen articles were included in this state-of-the-science review. Overall, it was found that limited access to green space is significantly related to adverse birth outcomes. These findings present an important opportunity for childbirth educators and other clinicians involved in the provision of prenatal and reproductive health care. Through education and intervention, poor perinatal outcomes may be mitigated. Clinical screening and education about the importance of access to and use of urban green space during pregnancy should be an essential component of preconception counseling and antenatal screening for at-risk populations. Policy makers should be made aware of these findings so that impactful change can be made in order to reduce disparities and promote health equity.
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Carlson NS, Amore AD, Ellis JA, Page K, Schafer R. American College of Nurse-Midwives Clinical Bulletin Number 18: Induction of Labor. J Midwifery Womens Health 2022; 67:140-149. [PMID: 35119782 PMCID: PMC9026716 DOI: 10.1111/jmwh.13337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 12/20/2021] [Indexed: 11/27/2022]
Abstract
Induction of labor is an increasingly common component of intrapartum care in the United States. This rise is fueled by a nationwide escalation in both medically indicated and elective inductions at or beyond term, supported by recent research showing some benefits of induction over expectant management. However, induction of labor medicalizes the birth experience and may lead to a complex cascade of interventions. The purpose of this Clinical Bulletin is twofold: (1) to guide clinicians on the use of person-centered decision-making when discussing induction of labor and (2) to review evidence-based practice recommendations for intrapartum midwifery care during labor induction.
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Schafer R, Phillippi JC. Group B Streptococcal Bacteriuria in Pregnancy: An Evidence-Based, Patient-Centered Approach to Care. J Midwifery Womens Health 2020; 65:376-381. [PMID: 32096338 DOI: 10.1111/jmwh.13085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 12/10/2019] [Accepted: 12/17/2019] [Indexed: 11/29/2022]
Abstract
Screening and management of group B streptococcus (GBS) bacteriuria in pregnancy aims to reduce the incidence of pyelonephritis and GBS-related neonatal morbidity and mortality. Universal screening and management of GBS bacteriuria in pregnancy are standards of care in the United States; however, some women may decline guideline-based recommendations for screening, treatment, or intrapartum antibiotic prophylaxis. This article uses a case study approach to discuss evidence-based, patient-centered care for GBS bacteriuria in pregnancy as well as ethical incorporation of individual patient preferences and values.
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Schafer R, Davis M, Phillippi JC. Herpes Zoster in Pregnancy. J Midwifery Womens Health 2019; 64:230-235. [DOI: 10.1111/jmwh.12953] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 12/17/2018] [Accepted: 12/19/2018] [Indexed: 11/30/2022]
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Sikder A, Yang F, Schafer R, Dowling G, Jain F. MENTALIZING IMAGERY THERAPY MOBILE APPLICATION FOR FAMILY DEMENTIA CAREGIVERS: FEASIBILITY AND EFFECTS ON MOOD. Innov Aging 2018. [DOI: 10.1093/geroni/igy031.3640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Zahavi M, Zahavi J, Schafer R, Firsteter E, Laniado S. Abnormal Typical Pattern of Platelet Function and Thromboxane Generation in Unstable Angina. Thromb Haemost 2018. [DOI: 10.1055/s-0038-1651014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
SummaryPlatelet aggregation (PA), platelet thromboxane B2 (TXB2) generation and 14C 5-hydroxytryptamine (5HT) release were studied in 13 patients with unstable angina, and compared to 14 patients with stable angina and 16 healthy controls. A typical pattern, distinct in 4 aspects from stable angina patients or controls, was observed in the unstable angina patients. ADP or collagen induced shape change was 3-4 times greater, the extent of epinephrine induced PA was nil or very low, the extent of collagen induced 14C 5HT release was also reduced while collagen induced platelet TXB2 generation was increased in spite of a reduced extent of PA. The extent of ADP or collagen induced PA was also significantly reduced. These results indicate a platelet membrane abnormality occurring presumably during contact of the circulating platelets with a non-occlusive thrombus observed at sites of ruptured plaques in unstable angina patients. Since also the pattern (20-30% overlap with control values) was distinct from that of stable angina patients, it might indicate an active thrombotic process.Plasma β-thromboglobulin (βTG) and TXB2 levels and serum TXB2 generation were also studied in the cardiac patients and controls and in another 10 patients with advanced peripheral occlusive arterial disease (POAD). Plasma βTG and TXB2 levels were slightly elevated in the unstable angina patients and markedly elevated in the POAD patients. Serum TXB2 generation was, however, elevated in the stable angina patients (p <0.002) and more so in the unstable angina patients (p <0.001) compared to controls or to POAD patients. This was presumably mediated through enhanced thrombin generation. These results suggest that the measured plasma βTG variable in the unstable angina patients is not useful in the assessment of in vivo platelet activation. It is presumably reflecting the sum of local enhanced platelet activation (at sites of ruptured plaques) and of reduced function of the “defective” circulating platelets. The ability of the platelets of unstable angina patients to generate large amounts of TXB2 if occurring in vivo might induce an intense coronary vasospasm.
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Schafer R, Genna CW. Physiologic Breastfeeding: A Contemporary Approach to Breastfeeding Initiation. J Midwifery Womens Health 2015; 60:546-53. [DOI: 10.1111/jmwh.12319] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Ritsma L, Steller EJA, Beerling E, Loomans CJM, Zomer A, Gerlach C, Vrisekoop N, Seinstra D, van Gurp L, Schafer R, Raats DA, de Graaff A, Schumacher TN, de Koning EJP, Rinkes IHB, Kranenburg O, Rheenen JV. Intravital Microscopy Through an Abdominal Imaging Window Reveals a Pre-Micrometastasis Stage During Liver Metastasis. Sci Transl Med 2012; 4:158ra145. [DOI: 10.1126/scitranslmed.3004394] [Citation(s) in RCA: 159] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Kosters R, Adams V, Hassam S, Schafer R, Schmid M, Moos R, Briner J. Mutational analysis of the tumor-suppressor gene wt1 - detection of a novel homozygous point mutation in sporadic unilateral wilms-tumor. Int J Oncol 2012; 7:1103-7. [PMID: 21552938 DOI: 10.3892/ijo.7.5.1103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The WT1 gene located on chromosome 11p13, has been identified as the first Wilms' tumor suppressor gene and has been implicated in the development of Wilms' tumor. About 10% of Wilms' tumors analyzed to date carry a mutation and only 6 different point mutations affecting the zinc finger region have been reported. We analyzed the zinc finger coding exons of 38 sporadic Wilms' tumor by SSCP and detected 2 point mutations. One homo/hemizygous mutation, already described in the literature, replaced an arginine in zinc finger II by a stop codon. The other mutation, a replacement of an arginine by a stop codon in zinc finger I, represents a novel mutation.
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Kuznia C, Klinger B, Keil J, Seliger B, Falk C, Schafer R, Blüthgen N, Sers C. 987 Molecular Mechanisms of Sorafenib-induced Apoptosis in Cancer Cells. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)71605-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Woodburn K, Holmes C, Fong KL, Sloneker S, Strzemienski P, Solon E, Ryckelynck JP, Lang P, Bataille P, Choukroun G, Esnault V, Knebelman B, Laville M, Fellous M, Legrand E, Portoles J, Vega NJ, Fernandez-Fresnedo G, Perez A, Bea S, Camba MJ, Leistikow F, Heidenreich S, Cases A, Portoles J, Calls J, Martinez Castelao A, Sanchez-Guisande D, Espinel E, Carreno A, Campistol JM, Arias M, Morales JM, Pallardo L, Franco A, Shestakova M, Heidenreich S, Tsubakihara Y, Bessho M, Suzuki M, Correa-Rotter R, Niihata K, Tomosugi N, Uehata T, Shoji T, Sonoda M, Kawabata H, Sakaguchi Y, Suzuki A, Okada N, Tsubakihara Y, Kuragano T, Shimonaka Y, Kida A, Kitamura R, Furuta M, Yahiro M, Otaki Y, Nisihara F, Nonoguchi H, Nakanishi T, Mircescu G, Stancu S, Stanciu A, Viasu L, Capusa C, Petrescu L, Zugravu A, Aydin Z, Gursu M, Uzun S, Karadag S, Tatli E, Sumnu A, Doventas Y, Koldas M, Ozturk S, Kazancioglu R, Malyszko Y, Levin-Iaina N, Malyszko J, Kozminski P, Koc-Zorawska E, Mysliwiec M, Hara M, Ando M, Tsuchiya K, Nitta K, Mirescu G, Deray G, Garneata L, Goldsmith D, Gorriz Teruel JL, Martin PY, Mitchell D, Mori C, Schafer R, Guerin A, Addison J, Bridges I, Di Giulio S, Farouk M, Winearls C, Kiss I, Claes K, Galle J, Costa E, Rocha-Pereira P, Sameiro-Faria M, Miranda V, Afonso C, Belo L, Marinho C, Bicho M, Santos-Silva A, Kim HW, Jang EH, Mercadal L, Metzger M, Casadevall N, Haymann JP, Boffa JJ, Flamant M, Vrtovsnik F, Stengel B, Froissart M, Ode M, Roth K, Locatelli F, Horl WH. Anaemia in CKD 1-5. Clin Kidney J 2011. [DOI: 10.1093/ndtplus/4.s2.32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Soderberg LSF, Ponnappan U, Roy A, Schafer R, Barnett JB. Production of macrophage IL-1beta was inhibited both at the levels of transcription and maturation by caspase-1 following inhalation exposure to isobutyl nitrite. Toxicol Lett 2004; 152:47-56. [PMID: 15294346 DOI: 10.1016/j.toxlet.2004.03.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2003] [Revised: 03/29/2004] [Accepted: 03/29/2004] [Indexed: 11/21/2022]
Abstract
Epidemiological studies have identified abuse of nitrite inhalants as an independent co-factor in HIV infection and in Kaposi's sarcoma (KS) in AIDS patients. In the present study we investigated the ability of macrophages from mice exposed to isobutyl nitrite to produce the inflammatory cytokine IL-1beta, upon stimulation with IFN-gamma and LPS. The production of IL-1beta was inhibited up to 55%. IL-1beta mRNA transcription was reduced by 35% following nitrite inhalant exposure, consistent with inhibition of activation-induced phosphorylation of macrophage mitogen-activated protein kinase p38. However, synthesis of the 31 kDa IL-1beta precursor protein was only marginally inhibited. Caspase-1, which cleaves the precursor IL-1beta into mature 17 kDa IL-1beta, was examined. Nitrite inhalant exposure blocked activation-induced increases in caspase-1 activity, consistent with a 50% reduction in 17 kDa IL-1beta shown in Western blots. Thus, exposure to nitrite inhalants reduced macrophage production of IL-1beta by reducing transcription, as well as post-translational processing mediated by caspase-1.
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Brundage KM, Schafer R, Barnett JB. Altered AP-1 (activating protein-1) activity and c-jun activation in T cells exposed to the amide class herbicide 3,4-dichloropropionanilide (DCPA). Toxicol Sci 2004; 79:98-105. [PMID: 14976341 DOI: 10.1093/toxsci/kfh090] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
3,4-Dichloropropionanilide (DCPA), the active ingredient of some postemergence herbicides, has been demonstrated to inhibit several immune system functions including cytokine production by T cells. The central role of cytokines in regulating the immune response suggests a possible mechanism by which DCPA inhibits the immune system. Since interleukin (IL)-2 is critical in regulating many immune functions, we chose to investigate the effect of DCPA on this cytokine. Using the human T lymphoma line, Jurkat, stimulated with phorbol-12-myristate acetate (PMA) and the calcium ionophore A23187 (Io), we determined that DCPA exposure decreased IL-2 secretion and mRNA levels in a dose dependent manner. We hypothesized that DCPA affected one or more of the transcription factors that regulate IL-2 gene transcription. Activating protein 1(AP-1) is a transcription factor that has been demonstrated to be required for optimal IL-2 gene transcription. Electrophoretic mobility shift assays (EMSAs) demonstrated a decreased level of AP-1 DNA binding activity in DCPA-exposed Jurkat cells compared to control cells from 30 min to 2 h after stimulation. The altered AP-1 DNA binding kinetics was associated with a decrease in c-jun protein in these cells at 1 and 2 h after exposure and a decreased level of phosphorylated c-jun at 1-4 h after exposure. These results suggest a possible mechanism for DCPA-induced IL-2 inhibition; alteration in the activation of the c-jun component of AP-1.
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Huegl B, Grosse A, Germer A, Schafer R, Hartkopf T, Gohl K, Lauer B, Klein HU, Geller JC. A23-4 Improved efficacy of atrial overdrive pacing in patients with atrial fibrillation using hybrid-therapy (amiodarone or right atrial linear ablation) first results of a multicenter study: MEDAB. Europace 2003. [DOI: 10.1016/eupace/4.supplement_2.b35-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
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Pflugrath JW, Athay R, Edwards DP, Niemeyer TJ, Hendrixson TL, Criswell AR, Yang C, Crane GK, Ferrara JD, Nienaber T, Robertson W, Schafer R. ACTOR: automated crystal transport, orientation and retrieval. Acta Crystallogr A 2002. [DOI: 10.1107/s0108767302087895] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Ebadi M, Govitrapong P, Sharma S, Muralikrishnan D, Shavali S, Pellett L, Schafer R, Albano C, Eken J. Ubiquinone (Coenzyme Q 10) and Mitochondria in Oxidative Stress of Parkinson’s Disease. Neurosignals 2001; 10:224-53. [PMID: 11351130 DOI: 10.1159/000046889] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Parkinson's disease is the second most common neurodegenerative disorder after Alzheimer's disease affecting approximately1% of the population older than 50 years. There is a worldwide increase in disease prevalence due to the increasing age of human populations. A definitive neuropathological diagnosis of Parkinson's disease requires loss of dopaminergic neurons in the substantia nigra and related brain stem nuclei, and the presence of Lewy bodies in remaining nerve cells. The contribution of genetic factors to the pathogenesis of Parkinson's disease is increasingly being recognized. A point mutation which is sufficient to cause a rare autosomal dominant form of the disorder has been recently identified in the alpha-synuclein gene on chromosome 4 in the much more common sporadic, or 'idiopathic' form of Parkinson's disease, and a defect of complex I of the mitochondrial respiratory chain was confirmed at the biochemical level. Disease specificity of this defect has been demonstrated for the parkinsonian substantia nigra. These findings and the observation that the neurotoxin 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP), which causes a Parkinson-like syndrome in humans, acts via inhibition of complex I have triggered research interest in the mitochondrial genetics of Parkinson's disease. Oxidative phosphorylation consists of five protein-lipid enzyme complexes located in the mitochondrial inner membrane that contain flavins (FMN, FAD), quinoid compounds (coenzyme Q10, CoQ10) and transition metal compounds (iron-sulfur clusters, hemes, protein-bound copper). These enzymes are designated complex I (NADH:ubiquinone oxidoreductase, EC 1.6. 5.3), complex II (succinate:ubiquinone oxidoreductase, EC 1.3.5.1), complex III (ubiquinol:ferrocytochrome c oxidoreductase, EC 1.10.2.2), complex IV (ferrocytochrome c:oxygen oxidoreductase or cytochrome c oxidase, EC 1.9.3.1), and complex V (ATP synthase, EC 3.6.1.34). A defect in mitochondrial oxidative phosphorylation, in terms of a reduction in the activity of NADH CoQ reductase (complex I) has been reported in the striatum of patients with Parkinson's disease. The reduction in the activity of complex I is found in the substantia nigra, but not in other areas of the brain, such as globus pallidus or cerebral cortex. Therefore, the specificity of mitochondrial impairment may play a role in the degeneration of nigrostriatal dopaminergic neurons. This view is supported by the fact that MPTP generating 1-methyl-4-phenylpyridine (MPP(+)) destroys dopaminergic neurons in the substantia nigra. Although the serum levels of CoQ10 is normal in patients with Parkinson's disease, CoQ10 is able to attenuate the MPTP-induced loss of striatal dopaminergic neurons.
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Frost LL, Neeley YX, Schafer R, Gibson LF, Barnett JB. Propanil inhibits tumor necrosis factor-alpha production by reducing nuclear levels of the transcription factor nuclear factor-kappab in the macrophage cell line ic-21. Toxicol Appl Pharmacol 2001; 172:186-93. [PMID: 11312646 DOI: 10.1006/taap.2001.9153] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Tumor necrosis factor-alpha (TNF-alpha) is an essential proinflammatory cytokine whose production is normally stimulated by bacterial cell wall components, such as lipopolysaccharide (LPS), during an infection. Macrophages stimulated with LPS in vitro produce several cytokines, including TNF-alpha. LPS-stimulated primary mouse macrophages produced less TNF-alpha protein and message after treatment with the herbicide propanil (Xie et al., Toxicol. Appl. Pharmacol. 145, 184-191, 1997). Nuclear factor-kappaB (NF-kappaB) tightly regulates TNF-alpha transcription. Therefore, as a step toward understanding the mechanism of the effect of propanil on TNF-alpha transcription, IC-21 cells were transfected with a TNF-alpha promoter-luciferase construct, and the effect of propanil on luciferase activity was measured. Cells transfected with promoter constructs containing a kappaB site showed decreased luciferase activity relative to controls after propanil treatment. These observations implicated NF-kappaB binding as an intracellular target of propanil. Further studies demonstrated a marked reduction in the nuclear levels of the stimulatory p65 subunit of NF-kappaB after propanil treatment, as measured by fluorescence confocal microscopy and Western blot analysis. The p50 subunit of NF-kappaB was not found to be reduced after propanil exposure by Western blot. Electrophoretic mobility gel shift assays showed decreased DNA binding of both p65/p50 heterodimers and p50/p50 homodimers to the kappaB3 site of the TNF-alpha promoter of propanil-treated cells. The marked reduction in nuclear p65/p50 NF-kappaB levels and diminished binding to the TNF-alpha promoter in propanil-treated cells are consistent with reduced TNF-alpha levels induced by LPS.
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Bachels T, Guntherodt HJ, Schafer R. Melting of isolated tin nanoparticles. PHYSICAL REVIEW LETTERS 2000; 85:1250-1253. [PMID: 10991524 DOI: 10.1103/physrevlett.85.1250] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2000] [Indexed: 05/23/2023]
Abstract
The melting of isolated neutral tin cluster distributions with mean sizes of about 500 atoms has been investigated in a molecular beam experiment by calorimetrically measuring the clusters' formation energies as a function of their internal temperature. For this purpose the possibility to adjust the temperature of the clusters' internal degrees of freedom by means of the temperature of the cluster source's nozzle was exploited. The melting point of the investigated tin clusters was found to be lowered by 125 K and the latent heat of fusion per atom is reduced by 35% compared to bulk tin. The melting behavior of the isolated tin clusters is discussed with respect to the occurrence of surface premelting.
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Watson VA, Barnett JB, Schafer R. In vivo cytokine production and resistance to infection after acute exposure to 3,4-dichloropropionaniline. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2000; 60:391-406. [PMID: 10933756 DOI: 10.1080/00984100050033476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
3,4-Dichloropropionaniline (propanil) is an extensively used postemergent herbicide that has been shown to produce toxic and immunotoxic effects. The present report examined if acute exposure to propanil altered in vitro or in vivo cytokine production in response to antigenic stimulation. Studies to determine resistance to infection by the intracellular bacterium Listeria monocytogenes after exposure to propanil were also conducted. Our experiments demonstrate that in vivo exposure to propanil during bacterial infection reduced the subsequent in vitro production of interferon-gamma (IFN-gamma) by splenocytes and liver nonparenchymal cells in response to antigenic and mitogenic stimulation. Additional experiments examined the production of cytokines in vivo after propanil exposure alone or combined propanil exposure and L. monocytogenes infection. It was found that the endogenous levels of cytokines in the liver, spleen, and blood were similar in control and propanil-treated mice. The levels of cytokines were also similar in control and exposed mice that were infected with L. monocytogenes. Initial resistance to the infection was not affected by exposure to propanil. These results demonstrate that in vivo exposure to propanil during a bacterial infection suppresses the subsequent in vitro production of cytokines but that the endogenous levels are not affected during the initial stages of infection.
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