143 research outputs found
The effect of enteral bolus feeding on regional intestinal oxygen saturation in preterm infants is age-dependent:a longitudinal observational study
Background The factors that determine the effect of enteral feeding on intestinal perfusion after preterm birth remain largely unknown. We aimed to determine the effect of enteral feeding on intestinal oxygen saturation (r(int)SO(2)) in preterm infants and evaluated whether this effect depended on postnatal age (PNA), postmenstrual age (PMA), and/or feeding volumes. We also evaluated whether changes in postprandial r(int)SO(2) affected cerebral oxygen saturation (r(c)SO(2)). Methods In a longitudinal observational pilot study using near-infrared spectroscopy we measured r(int)SO(2) and r(c)SO(2) continuously for two hours on postnatal Days 2 to 5, 8, 15, 22, 29, and 36. We compared preprandial with postprandial values over time using multi-level analyses. To assess the effect of PNA, PMA, and feeding volumes, we performed Wilcoxon signed-rank tests or logistic regression analyses. To evaluate the effect on r(c)SO(2), we also used logistic regression analyses. Results We included 29 infants: median (range) gestational age 28.1 weeks (25.1-30.7) and birth weight 1025 g (580-1495). On Day 5, r(int)SO(2) values decreased postprandially: mean (SE) 44% (10) versus 35% (7), P = .01. On Day 29, r(int)SO(2) values increased: 44% (11) versus 54% (7), P = .01. Infants with a PMA >= 32 weeks showed a r(int)SO(2) increase after feeding (37% versus 51%, P = .04) whereas infants with a PMA = 32 weeks when greater volumes of enteral feeding are tolerated. We speculate that at young gestational and postmenstrual ages preterm infants are still unable to increase intestinal oxygen saturation after feeding, which might be essential to meet metabolic demands. Trial registration: For this prospective longitudinal pilot study we derived patients from a larger observational cohort study: CALIFORNIA-Trial, Dutch Trial Registry NTR4153
Duurzame bestrijding tulpengalmijt : onderzoek naar de effectiviteit van de roofmijt Neoseiulus paspalivorus tegen tulpengalmijt Aceria tulipae en onderzoek naar alternatieve voedselbronnen voor N. paspalivorus
Tulpengalmijt vormt de grootste plaag in de bewaring van tulpen, is een risico voor verspreiding van TVX en kost de sector jaarlijks miljoenen euro’s. Huidige bestrijdingsmethodes werken in praktijk niet voldoende. Eerder onderzoek heeft aangetoond dat de roofmijt Neoseiulus paspalivorus tulpengalmijt in de bewaring goed in toom kan houden (project 14745). In een vervolgproef werd weer aangetoond dat de kleine roofmijt een goede bestrijder is van tulpengalmijt. Verder is er een stap gezet naar massakweek van de roofmijt door het vinden van alternatieve voedselbronnen. Met producenten van biologische bestrijders zijn contacten gelegd om de mogelijkheden voor commerciële massakweek te verkennen
Neoseiulus paspalivorus, een nieuwe bestrijder van tulpengalmijt?!
Tulpengalmijt vormt de grootste plaag in de bewaring van tulpen, is een risico voor verspreiding van TVX en kost de sector jaarlijks miljoenen euro’s. Huidige bestrijdingsmethodes werken in praktijk niet bevredigend en de toekomst van chemische middelen is onduidelijk. Reden voor PPO en de Universiteit van Amsterdam om samen onderzoek te doen naar alternatieve bestrijdingsmethode met roofmijten. De eerste proeven tonen aan dat de Braziliaanse rover Neoseiulus paspalivorus tulpengalmijt in de bewaring in toom kan houden en zichzelf goed kan handhaven. Hij presteert daarbij vele malen beter dan de eerder onderzochte Neoseiulus cucumeris. Vertegenwoordigers uit de praktijk zien kansen voor deze nieuwe roofmijt maar hebben nog veel vragen
Intestinal Oxygenation and Survival After Surgery for Necrotizing Enterocolitis:An Observational Cohort Study
OBJECTIVE: To assess whether regional intestinal oxygen saturation (rintSO2) and regional cerebral oxygen saturation (rcSO2) measurements aid in estimating survival of preterm infants after surgery for NEC. SUMMARY OF BACKGROUND DATA: Predicting survival after surgery for NEC is difficult yet of the utmost importance for counseling parents. METHODS: We retrospectively studied prospectively collected data of preterm infants with surgical NEC who had available rintSO2 and rcSO2 values measured via near-infrared spectroscopy 0-24 hours preoperatively. We calculated mean rintSO2 and rcSO2 for 60-120 minutes for each infant. We analyzed whether preoperative rintSO2 and rcSO2 differed between survivors and non-survivors, determined cut-off points, and assessed the added value to clinical variables. RESULTS: We included 22 infants, median gestational age 26.9 weeks [interquartile range (IQR): 26.3-28.4], median birth weight 1088 g [IQR: 730-1178]. Eleven infants died postoperatively. Preoperative rintSO2, but not rcSO2, was higher in survivors than in non-survivors [median: 63% (IQR: 42-68) vs 29% (IQR: 21-43), P 53% survived, whereas all infants with rintSO2 <35% died. Median C-reactive protein [138 mg/L (IQR: 83-179) vs 73 mg/L (IQR: 12-98), P < 0.01), lactate [1.1 mmol/L (IQR: 1.0-1.6) vs 4.6 mmol/L (IQR: 2.8-8.0), P < 0.01], and fraction of inspired oxygen [25% (IQR: 21-31) vs 42% (IQR: 30-80), P < 0.01] differed between survivors and non-survivors. Only rintSO2 remained significant in the multiple regression model. CONCLUSIONS: Measuring rintSO2, but not rcSO2, seems of added value to clinical variables in estimating survival of preterm infants after surgery for NEC. This may help clinicians in deciding whether surgery is feasible and to better counsel parents about their infants' chances of survival
Inherited susceptibility to bleomycin-induced chromatid breaks in cultured peripheral blood lymphocytes
Background: Susceptibility to bleomycin-induced chromatid breaks in cultured peripheral blood lymphocytes may reflect the way a person deals with carcinogenic challenges. This susceptibility (also referred to as mutagen sensitivity) has been found to be increased in patients with environmentally related cancers, including cancers of the head and neck, lung, and colon, and, in combination with carcinogenic exposure, this susceptibility can greatly influence cancer risk. The purpose of this study was to assess the heritability of mutagen sensitivity. Methods: Heritability was determined by use of a maximum likelihood method that employed the FISHER package of pedigree analysis. Bleomycin-induced breaks per cell values for 135 healthy volunteers without cancer were determined. These individuals were from 53 different pedigrees and included 25 monozygotic twin pairs (n = 50), 14 pairs of dizygotes (twin pairs and siblings, n = 28), and 14 families selected on the basis of a first-degree relative who was successfully treated for head and neck cancer and who had no sign of recurrence for at least 1 year. All data were analyzed simultaneously, and different models of familial resemblance were fitted to the data. All P values are two-sided. Results: Our results showed no evidence for the influence of a shared family environment on bleomycin-induced chromatid breaks. Genetic influences, however, were statistically significant (P = .036) and accounted for 75% of the total variance. Conclusions: The high heritability estimate of the susceptibility to bleomycin-induced chromatid breaks indicates a clear genetic basis. The findings of this study support the notion that a common genetic susceptibility to DNA damage - and thereby a susceptibility to cancer - may exist in the general population
Effect of tissue-harvesting site on yield of stem cells derived from adipose tissue: implications for cell-based therapies
The stromal vascular fraction (SVF) of adipose tissue contains an abundant population of multipotent adipose-tissue-derived stem cells (ASCs) that possess the capacity to differentiate into cells of the mesodermal lineage in vitro. For cell-based therapies, an advantageous approach would be to harvest these SVF cells and give them back to the patient within a single surgical procedure, thereby avoiding lengthy and costly in vitro culturing steps. However, this requires SVF-isolates to contain sufficient ASCs capable of differentiating into the desired cell lineage. We have investigated whether the yield and function of ASCs are affected by the anatomical sites most frequently used for harvesting adipose tissue: the abdomen and hip/thigh region. The frequency of ASCs in the SVF of adipose tissue from the abdomen and hip/thigh region was determined in limiting dilution and colony-forming unit (CFU) assays. The capacity of these ASCs to differentiate into the chondrogenic and osteogenic pathways was investigated by quantitative real-time polymerase chain reaction and (immuno)histochemistry. A significant difference (P = 0.0009) was seen in ASC frequency but not in the absolute number of nucleated cells between adipose tissue harvested from the abdomen (5.1 ± 1.1%, mean ± SEM) and hip/thigh region (1.2 ± 0.7%). However, within the CFUs derived from both tissues, the frequency of CFUs having osteogenic differentiation potential was the same. When cultured, homogeneous cell populations were obtained with similar growth kinetics and phenotype. No differences were detected in differentiation capacity between ASCs from both tissue-harvesting sites. We conclude that the yield of ASCs, but not the total amount of nucleated cells per volume or the ASC proliferation and differentiation capacities, are dependent on the tissue-harvesting site. The abdomen seems to be preferable to the hip/thigh region for harvesting adipose tissue, in particular when considering SVF cells for stem-cell-based therapies in one-step surgical procedures for skeletal tissue engineering
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Science for loss and damage. Findings and propositions
The debate on “Loss and Damage” (L&D) has gained traction over the last few years. Supported by growing scientific evidence of anthropogenic climate change amplifying frequency, intensity and duration of climate-related hazards as well as observed increases in climate-related impacts and risks in many regions, the “Warsaw International Mechanism for Loss and Damage” was established in 2013 and further supported through the Paris Agreement in 2015. Despite advances, the debate currently is broad, diffuse and somewhat confusing, while concepts, methods and tools, as well as directions for policy remain vague and often contested. This book, a joint effort of the Loss and Damage Network—a partnership effort by scientists and practitioners from around the globe—provides evidence-based insight into the L&D discourse by highlighting state-of-the-art research conducted across multiple disciplines, by showcasing applications in practice and by providing insight into policy contexts and salient policy options. This introductory chapter summarises key findings of the twenty-two book chapters in terms of five propositions. These propositions, each building on relevant findings linked to forward-looking suggestions for research, policy and practice, reflect the architecture of the book, whose sections proceed from setting the stage to critical issues, followed by a section on methods and tools, to chapters that provide geographic perspectives, and finally to a section that identifies potential policy options. The propositions comprise (1) Risk management can be an effective entry point for aligning perspectives and debates, if framed comprehensively, coupled with climate justice considerations and linked to established risk management and adaptation practice; (2) Attribution science is advancing rapidly and fundamental to informing actions to minimise, avert, and address losses and damages; (3) Climate change research, in addition to identifying physical/hard limits to adaptation, needs to more systematically examine soft limits to adaptation, for which we find some evidence across several geographies globally; (4) Climate risk insurance mechanisms can serve the prevention and cure aspects emphasised in the L&D debate but solidarity and accountability aspects need further attention, for which we find tentative indication in applications around the world; (5) Policy deliberations may need to overcome the perception that L&D constitutes a win-lose negotiation “game” by developing a more inclusive narrative that highlights collective ambition for tackling risks, mutual benefits and the role of transformation
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