Frank Louwen | Goethe-Universität Frankfurt am Main (original) (raw)

Papers by Frank Louwen

The Journal of Pediatrics, Jun 1, 1999

Fetal Diagnosis and Therapy, 2003

Objective: Recent studies have shown a regular prenatal transfer of maternal immunocompetent cell... more Objective: Recent studies have shown a regular prenatal transfer of maternal immunocompetent cells into the fetal circulation. However, these cells engraft and proliferate only in a few exceptional cases if the fetus reaches an immunocompetent state. Thus the fetus has to have an immunologic defense mechanism against the engraftment of maternal cells. In the current study we investigated whether the fetus has such an immune defense and whether this defense mechanism specifically attacks cells of the mother. Patients, Material and Methods: Blood samples were obtained from 15 mothers and 15 newborns directly after delivery. We compared individual vitality and spontaneous cytotoxicity between fetal and maternal lymphocytes in a cell ratio of 1:1 in nonstimulated bidirectional mixed lymphocyte cultures (MLC). The distribution of each cell population within the MLC was visualized by fluorescence in situ hybridization and X/Y-DNA probes. This was compared to MLCs between unrelated fetal and maternal as well as between unrelated adult lymphocytes. Results: After 72 h, a significant cell shift was observed only in the MLC with neonatal lymphocytes mixed with cells of their own mother; there was a significantly higher number of neonatal cells (0.71 vs. 0.29) present. All other groups continued to have a cell distribution of 1:1. Conclusion: Our results show that neonatal lymphocytes specifically dominate against maternal but not allogenous maternal or adult lymphocytes in nonstimulated bidirectional MLCs.

Journal of Clinical Medicine

Cancer Research, 2022

It is well documented that obesity, characterized by an increased body mass index (BMI≥30), is an... more It is well documented that obesity, characterized by an increased body mass index (BMI≥30), is an important risk factor for the development of aggressive breast cancer (BC), which is associated with a reduced overall survival rate and decreased treatment response. The tumor microenvironment (TME), a cellular network majorly constructed by adipocytes, adipose-derived mesenchymal stem/stromal cells (bASCs) and immune cells, impacts progression of breast cancer and treatment response of patients. This study aims to examine how obesity influences the functional characteristics of bASCs in comparison to lean bASCs in the TME. To address this issue, various molecular, biological and cellular methods are applied including transcriptomic profiling and functional assays to characterize at first the features of bASCs in the TME (adjacent to tumor; -aT/distant to tumor; -dT) in obese (ob-) and lean (ln-) bASCs (n=5, for each group) patients with breast cancer. Second, based on the transcriptom...

License, which permits unrestricted use, distribution, and reproduction in any medium, provided t... more License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. To examine the effects of clinical hypnosis versus NLP intervention on the success rate of ECV procedures in comparison to a control group. Methods. A prospective off-centre randomised trial of a clinical hypnosis intervention against NLP of women with a singleton breech fetus at or after 370/7 (259 days) weeks of gestation and normal amniotic fluid index. All 80 participants heard a 20-minute recorded intervention via head phones. Main outcome assessed was success rate of ECV. The intervention groups were compared with a control group with standard medical care alone (n = 122). Results. A total of 42 women, who received a hypnosis intervention prior to ECV, had a 40.5 % (n = 17), successful ECV, whereas 38 women, who received NLP, had a 44.7 % (n = 17) successful ECV (P> 0.05). The control group had similar patient characteristics compar...

Abstract: Caesarean section (CS) is a common surgical procedure. Although it has been performed i... more Abstract: Caesarean section (CS) is a common surgical procedure. Although it has been performed in a modern context for about 100 years, there is no concise analysis of the international architecture of caesarean section research output available so far. Therefore, the present study characterizes the global pattern of the related publications by using the NewQIS (New Quality and Quantity Indices in Science) platform, which combines scientometric methods with density equalizing mapping algorithms. The Web of Science was used as a database. 12,608 publications were identified that originated from 131 countries. The leading nations concerning research activity, overall citations and country-specific h-Index were the USA and the United Kingdom. Relation of the research activity to epidemiologic data indicated that Scandinavian countries including Sweden and Finland were leading the field, whereas, in relation to economic data, countries such as Israel and

Journal of Obstetrics and Gynaecology Research, 2020

The aim of this study is to utilize the niche measurement guidelines outlined by Jordans et al. i... more The aim of this study is to utilize the niche measurement guidelines outlined by Jordans et al. in order to establish normal values and accurate description of caesarean section scars in a normal population. After defining the normal distribution, abnormal pregestational scar characteristics will be identified for predicting adverse pregnancy outcomes.

BMC Health Services Research, 2019

Background Patient safety is a key target in public health, health services and medicine. Communi... more Background Patient safety is a key target in public health, health services and medicine. Communication between all parties involved in gynecology and obstetrics (clinical staff/professionals, expectant mothers/patients and their partners, close relatives or friends providing social support) should be improved to ensure patient safety, including the avoidance of preventable adverse events (pAEs). Therefore, interventions including an app will be developed in this project through a participatory approach integrating two theoretical models. The interventions will be designed to support participants in their communication with each other and to overcome difficulties in everyday hospital life. The aim is to foster effective communication in order to reduce the frequency of pAEs. If communication is improved, clinical staff should show an increase in work satisfaction and patients should show an increase in patient satisfaction. Methods The study will take place in two maternity clinics ...

Veterinary Microbiology, 2013

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2019

International Journal of Environmental Research and Public Health, 2022

Background: The COVID-19 pandemic and the necessary containment measures challenge obstetric care... more Background: The COVID-19 pandemic and the necessary containment measures challenge obstetric care. Support persons were excluded while protection measures burdened and disrupted the professionals’ ability to care and communicate. The objective of this study was to explore the first-hand experience of the impact of the COVID-19 pandemic on mothers, their partners, and obstetric professionals regarding birth and obstetric care in a university hospital. Methods: To answer the descriptive research questions, we conducted a qualitative content analysis using a data triangulation approach. We carried out 35 semi-structured interviews with two stratified purposive samples. Sample one consisted of 25 mothers who had given birth during the pandemic and five partners. Sample two included 10 obstetric professionals whose insights complemented the research findings and contributed to data validation. Participants were recruited from the study sample of a larger project on patient safety from tw...

Doppler examination of the umbilical artery and the fetal middle cerebral artery is evaluated pre... more Doppler examination of the umbilical artery and the fetal middle cerebral artery is evaluated predominantly in pregnancies with fetuses in cephalic presentation and never has been elucidated in breech presentation. Evidence on the accuracy of fetal weight estimation in dependence of the fetal presentation is controversial. Nevertheless, clinical decisions including recommendations for a cesarean section or labor induction based on these examinations are applied to pregnancies with fetuses in breech presentation. The objective of this study was to investigate the influence of the fetal presentation on fetal weight estimation accuracy, umbilical artery and middle cerebral artery resistance indices (RI) in a prospective case control study. Ultrasound examinations in 305 uncomplicated term pregnancies (153 vertex presentations, 152 breech) were investigated. Non-parametric variables were compared using Pearson’s chi2 test and Wilcoxon chi2 test, depending on variable scaling. Fetal weig...

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2019

American Journal of Hypertension, 2000

BioMed research international, 2014

To compare the efficacy, safety, and patient's perception of two prostaglandin E2 application... more To compare the efficacy, safety, and patient's perception of two prostaglandin E2 application methods for induction of labour. Above 36th weeks of gestation, all women, who were admitted to hospital for induction of labour, were prospectively randomised to intravaginal 1 mg or intracervical 0.5 mg irrespective of cervical Bishop score. The main outcome variables were induction-to-delivery interval, number of foetal blood samples, PDA rate, rate of oxytocin augmentation, rate of vaginal delivery, and patient's perception using semantic differential questionnaire. Thirty-nine patients were enrolled in this study. There was no statistical significant difference between the two groups in regard to perceptions of induction. The median induction delivery time using intravaginal versus intracervical administration was 29.9 versus 12.8 hours, respectively (P = 0.04). No statistically difference between the groups was detected in regard to parity, gestation age, cervical Bishop score...

The Journal of Pediatrics, Jun 1, 1999

Fetal Diagnosis and Therapy, 2003

Objective: Recent studies have shown a regular prenatal transfer of maternal immunocompetent cell... more Objective: Recent studies have shown a regular prenatal transfer of maternal immunocompetent cells into the fetal circulation. However, these cells engraft and proliferate only in a few exceptional cases if the fetus reaches an immunocompetent state. Thus the fetus has to have an immunologic defense mechanism against the engraftment of maternal cells. In the current study we investigated whether the fetus has such an immune defense and whether this defense mechanism specifically attacks cells of the mother. Patients, Material and Methods: Blood samples were obtained from 15 mothers and 15 newborns directly after delivery. We compared individual vitality and spontaneous cytotoxicity between fetal and maternal lymphocytes in a cell ratio of 1:1 in nonstimulated bidirectional mixed lymphocyte cultures (MLC). The distribution of each cell population within the MLC was visualized by fluorescence in situ hybridization and X/Y-DNA probes. This was compared to MLCs between unrelated fetal and maternal as well as between unrelated adult lymphocytes. Results: After 72 h, a significant cell shift was observed only in the MLC with neonatal lymphocytes mixed with cells of their own mother; there was a significantly higher number of neonatal cells (0.71 vs. 0.29) present. All other groups continued to have a cell distribution of 1:1. Conclusion: Our results show that neonatal lymphocytes specifically dominate against maternal but not allogenous maternal or adult lymphocytes in nonstimulated bidirectional MLCs.

Journal of Clinical Medicine

Cancer Research, 2022

It is well documented that obesity, characterized by an increased body mass index (BMI≥30), is an... more It is well documented that obesity, characterized by an increased body mass index (BMI≥30), is an important risk factor for the development of aggressive breast cancer (BC), which is associated with a reduced overall survival rate and decreased treatment response. The tumor microenvironment (TME), a cellular network majorly constructed by adipocytes, adipose-derived mesenchymal stem/stromal cells (bASCs) and immune cells, impacts progression of breast cancer and treatment response of patients. This study aims to examine how obesity influences the functional characteristics of bASCs in comparison to lean bASCs in the TME. To address this issue, various molecular, biological and cellular methods are applied including transcriptomic profiling and functional assays to characterize at first the features of bASCs in the TME (adjacent to tumor; -aT/distant to tumor; -dT) in obese (ob-) and lean (ln-) bASCs (n=5, for each group) patients with breast cancer. Second, based on the transcriptom...

License, which permits unrestricted use, distribution, and reproduction in any medium, provided t... more License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. To examine the effects of clinical hypnosis versus NLP intervention on the success rate of ECV procedures in comparison to a control group. Methods. A prospective off-centre randomised trial of a clinical hypnosis intervention against NLP of women with a singleton breech fetus at or after 370/7 (259 days) weeks of gestation and normal amniotic fluid index. All 80 participants heard a 20-minute recorded intervention via head phones. Main outcome assessed was success rate of ECV. The intervention groups were compared with a control group with standard medical care alone (n = 122). Results. A total of 42 women, who received a hypnosis intervention prior to ECV, had a 40.5 % (n = 17), successful ECV, whereas 38 women, who received NLP, had a 44.7 % (n = 17) successful ECV (P> 0.05). The control group had similar patient characteristics compar...

Abstract: Caesarean section (CS) is a common surgical procedure. Although it has been performed i... more Abstract: Caesarean section (CS) is a common surgical procedure. Although it has been performed in a modern context for about 100 years, there is no concise analysis of the international architecture of caesarean section research output available so far. Therefore, the present study characterizes the global pattern of the related publications by using the NewQIS (New Quality and Quantity Indices in Science) platform, which combines scientometric methods with density equalizing mapping algorithms. The Web of Science was used as a database. 12,608 publications were identified that originated from 131 countries. The leading nations concerning research activity, overall citations and country-specific h-Index were the USA and the United Kingdom. Relation of the research activity to epidemiologic data indicated that Scandinavian countries including Sweden and Finland were leading the field, whereas, in relation to economic data, countries such as Israel and

Journal of Obstetrics and Gynaecology Research, 2020

The aim of this study is to utilize the niche measurement guidelines outlined by Jordans et al. i... more The aim of this study is to utilize the niche measurement guidelines outlined by Jordans et al. in order to establish normal values and accurate description of caesarean section scars in a normal population. After defining the normal distribution, abnormal pregestational scar characteristics will be identified for predicting adverse pregnancy outcomes.

BMC Health Services Research, 2019

Background Patient safety is a key target in public health, health services and medicine. Communi... more Background Patient safety is a key target in public health, health services and medicine. Communication between all parties involved in gynecology and obstetrics (clinical staff/professionals, expectant mothers/patients and their partners, close relatives or friends providing social support) should be improved to ensure patient safety, including the avoidance of preventable adverse events (pAEs). Therefore, interventions including an app will be developed in this project through a participatory approach integrating two theoretical models. The interventions will be designed to support participants in their communication with each other and to overcome difficulties in everyday hospital life. The aim is to foster effective communication in order to reduce the frequency of pAEs. If communication is improved, clinical staff should show an increase in work satisfaction and patients should show an increase in patient satisfaction. Methods The study will take place in two maternity clinics ...

Veterinary Microbiology, 2013

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2019

International Journal of Environmental Research and Public Health, 2022

Background: The COVID-19 pandemic and the necessary containment measures challenge obstetric care... more Background: The COVID-19 pandemic and the necessary containment measures challenge obstetric care. Support persons were excluded while protection measures burdened and disrupted the professionals’ ability to care and communicate. The objective of this study was to explore the first-hand experience of the impact of the COVID-19 pandemic on mothers, their partners, and obstetric professionals regarding birth and obstetric care in a university hospital. Methods: To answer the descriptive research questions, we conducted a qualitative content analysis using a data triangulation approach. We carried out 35 semi-structured interviews with two stratified purposive samples. Sample one consisted of 25 mothers who had given birth during the pandemic and five partners. Sample two included 10 obstetric professionals whose insights complemented the research findings and contributed to data validation. Participants were recruited from the study sample of a larger project on patient safety from tw...

Doppler examination of the umbilical artery and the fetal middle cerebral artery is evaluated pre... more Doppler examination of the umbilical artery and the fetal middle cerebral artery is evaluated predominantly in pregnancies with fetuses in cephalic presentation and never has been elucidated in breech presentation. Evidence on the accuracy of fetal weight estimation in dependence of the fetal presentation is controversial. Nevertheless, clinical decisions including recommendations for a cesarean section or labor induction based on these examinations are applied to pregnancies with fetuses in breech presentation. The objective of this study was to investigate the influence of the fetal presentation on fetal weight estimation accuracy, umbilical artery and middle cerebral artery resistance indices (RI) in a prospective case control study. Ultrasound examinations in 305 uncomplicated term pregnancies (153 vertex presentations, 152 breech) were investigated. Non-parametric variables were compared using Pearson’s chi2 test and Wilcoxon chi2 test, depending on variable scaling. Fetal weig...

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2019

American Journal of Hypertension, 2000

BioMed research international, 2014

To compare the efficacy, safety, and patient's perception of two prostaglandin E2 application... more To compare the efficacy, safety, and patient's perception of two prostaglandin E2 application methods for induction of labour. Above 36th weeks of gestation, all women, who were admitted to hospital for induction of labour, were prospectively randomised to intravaginal 1 mg or intracervical 0.5 mg irrespective of cervical Bishop score. The main outcome variables were induction-to-delivery interval, number of foetal blood samples, PDA rate, rate of oxytocin augmentation, rate of vaginal delivery, and patient's perception using semantic differential questionnaire. Thirty-nine patients were enrolled in this study. There was no statistical significant difference between the two groups in regard to perceptions of induction. The median induction delivery time using intravaginal versus intracervical administration was 29.9 versus 12.8 hours, respectively (P = 0.04). No statistically difference between the groups was detected in regard to parity, gestation age, cervical Bishop score...