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"Langenberg, C"
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Diagnosing Polyparasitism in a High-Prevalence Setting in Beira, Mozambique: Detection of Intestinal Parasites in Fecal Samples by Microscopy and Real-Time PCR
by
Langenberg, Marijke C. C.
,
Vinkeles Melchers, Natalie V. S.
,
Meurs, Lynn
in
Adolescent
,
Adult
,
Aged
2017
Many different intestinal parasite species can co-occur in the same population. However, classic diagnostic tools can only frame a particular group of intestinal parasite species. Hence, one or two tests do not suffice to provide a complete picture of infecting parasite species in a given population. The present study investigated intestinal parasitic infections in Beira, Mozambique, i.e. in the informal settlement of Inhamudima. Diagnostic accuracy of five classical microscopy techniques and real-time PCR for the detection of a broad spectrum of parasites was compared.
A cross-sectional population-based survey was performed. One stool sample per participant (n = 303) was examined by direct smear, formal-ether concentration (FEC), Kato smear, Baermann method, coproculture and real-time PCR. We found that virtually all people (96%) harbored at least one helminth, and that almost half (49%) harbored three helminths or more. Remarkably, Strongyloides stercoralis infections were widespread with a prevalence of 48%, and Ancylostoma spp. prevalence was higher than that of Necator americanus (25% versus 15%), the hookworm species that is often assumed to prevail in East-Africa. Among the microscopic techniques, FEC was able to detect the broadest spectrum of parasite species. However, FEC also missed a considerable number of infections, notably S. stercoralis, Schistosoma mansoni and G. intestinalis. PCR outperformed microscopy in terms of sensitivity and range of parasite species detected.
We showed intestinal parasites-especially helminths-to be omnipresent in Inhamudima, Beira. However, it is a challenge to achieve high diagnostic sensitivity for all species. Classical techniques such as FEC are useful for the detection of some intestinal helminth species, but they lack sensitivity for other parasite species. PCR can detect intestinal parasites more accurately but is generally not feasible in resource-poor settings, at least not in peripheral labs. Hence, there is a need for a more field-friendly, sensitive approach for on-the-spot diagnosis of parasitic infections.
Journal Article
Multimodal prehabilitation to reduce the incidence of delirium and other adverse events in elderly patients undergoing elective major abdominal surgery: An uncontrolled before-and-after study
by
Janssen, T. L.
,
van Alphen, R.
,
de Lepper, C. C. H. A. van Hoof
in
Abdomen - physiopathology
,
Abdomen - surgery
,
Aged
2019
Delirium is a common and serious complication in elderly patients undergoing major abdominal surgery, with significant adverse outcomes. Successful strategies or therapies to reduce the incidence of delirium are scarce. The objective of this study was to assess the role of prehabilitation in reducing the incidence of delirium in elderly patients.
A single-center uncontrolled before-and-after study was conducted, including patients aged 70 years or older who underwent elective abdominal surgery for colorectal carcinoma or an abdominal aortic aneurysm between January 2013 and October 2015 (control group) and between November 2015 and June 2018 (prehabilitation group). The prehabilitation group received interventions to improve patients' physical health, nutritional status, factors of frailty and preoperative anaemia prior to surgery. The primary outcome was incidence of delirium, diagnosed with the DSM-V criteria or the confusion assessment method. Secondary outcomes were additional complications, length of stay, unplanned ICU admission, length of ICU stay, readmission rate, institutionalization, and in-hospital or 30-day mortality.
A total of 360 control patients and 267 prehabilitation patients were included in the final analysis. The mean number of prehabilitation days was 39 days. The prehabilitation group had a higher burden of comorbidities and was more physically and visually impaired at baseline. At adjusted logistic regression analysis, delirium incidence was reduced significantly from 11.7 to 8.2% (OR 0.56; 95% CI 0.32-0.98; P = 0.043). No statistically significant effects were seen on secondary outcomes.
Current prehabilitation program is feasible and safe, and can reduce delirium incidence in elderly patients undergoing elective major abdominal surgery. This program merits further evaluation.
Dutch Trial Registration, NTR5932.
Journal Article
Pulmonary inflammation promoted by type-2 dendritic cells is a feature of human and murine schistosomiasis
2023
Schistosomiasis is a parasitic disease affecting over 200 million people in multiple organs, including the lungs. Despite this, there is little understanding of pulmonary immune responses during schistosomiasis. Here, we show type-2 dominated lung immune responses in both patent (egg producing) and pre-patent (larval lung migration) murine
Schistosoma mansoni
(
S. mansoni)
infection. Human pre-patent
S. mansoni
infection pulmonary (sputum) samples revealed a mixed type-1/type-2 inflammatory cytokine profile, whilst a case-control study showed no significant pulmonary cytokine changes in endemic patent infection. However, schistosomiasis induced expansion of pulmonary type-2 conventional dendritic cells (cDC2s) in human and murine hosts, at both infection stages. Further, cDC2s were required for type-2 pulmonary inflammation in murine pre-patent or patent infection. These data elevate our fundamental understanding of pulmonary immune responses during schistosomiasis, which may be important for future vaccine design, as well as for understanding links between schistosomiasis and other lung diseases.
Schistosomiasis, a parasitic helminth infection, causes pulmonary symptoms during acute and chronic infection. Here, Houlder
et al
characterise the pulmonary immune response and demonstrate the role type 2 dendritic cells play in lung inflammation.
Journal Article
Plasmodium sporozoites induce regulatory macrophages
by
Winkel, Béatrice M. F.
,
Langenberg, Marijke C. C.
,
van Schuijlenburg, Roos
in
Antibodies
,
Antigen presenting cells
,
Antigens
2020
Professional antigen-presenting cells (APCs), like macrophages (M[PHI]s) and dendritic cells (DCs), are central players in the induction of natural and vaccine-induced immunity to malaria, yet very little is known about the interaction of SPZ with human APCs. Intradermal delivery of whole-sporozoite vaccines reduces their effectivity, possibly due to dermal immunoregulatory effects. Therefore, understanding these interactions could prove pivotal to malaria vaccination. We investigated human APC responses to recombinant circumsporozoite protein (recCSP), SPZ and anti-CSP opsonized SPZ both in monocyte derived MoDCs and MoM[PHI]s. Both MoDCs and MoM[PHI]s readily took up recCSP but did not change phenotype or function upon doing so. SPZ are preferentially phagocytosed by MoM[PHI]s instead of DCs and phagocytosis greatly increased after opsonization. Subsequently MoM[PHI]s show increased surface marker expression of activation markers as well as tolerogenic markers such as Programmed Death-Ligand 1 (PD-L1). Additionally they show reduced motility, produce interleukin 10 and suppressed interferon gamma (IFN[gamma]) production by antigen specific CD8.sup.+ T cells. Importantly, we investigated phenotypic responses to SPZ in primary dermal APCs isolated from human skin explants, which respond similarly to their monocyte-derived counterparts. These findings are a first step in enhancing our understanding of pre-erythrocytic natural immunity and the pitfalls of intradermal vaccination-induced immunity.
Journal Article
Renal blood flow in experimental septic acute renal failure
by
Egi, M.
,
May, C.N.
,
Wan, L.
in
Acute Kidney Injury - etiology
,
Acute Kidney Injury - physiopathology
,
acute renal failure
2006
Reduced renal blood flow (RBF) is considered central to the pathogenesis of septic acute renal failure (ARF). However, no controlled experimental studies have continuously assessed RBF during the development of severe septic ARF. We conducted a sequential animal study in seven female Merino sheep. Flow probes were implanted around the pulmonary and left renal arteries. Two weeks later, systemic hemodynamics and RBF were monitored continuously during a 48-h control period and, after a week, during a 48-h period of hyperdynamic sepsis induced by continuous Escherichia coli infusion. Infusion of E. coli induced hyperdynamic sepsis with significantly increased cardiac output (3.8±0.4 vs 9.8±1.1 l/min; P<0.05), decreased mean arterial pressure (89.2±3.2 vs 64.3±5.3 mm Hg; P<0.05), and increased total peripheral conductance (42.8±3.5 in controls vs 153.7±24.7 ml/min/mm Hg in septic animals; P<0.05). Hyperdynamic sepsis was associated with marked renal vasodilatation (renal conductance: 3.0±0.7 vs 11.4±3.4 ml/min/mm Hg; P<0.05) and a marked increase in RBF (262.3±47.7 vs 757.4±250.1 ml/min; P<0.05). Serum creatinine increased over 48 h (73±18 vs 305± μmol/l; P<0.05) whereas creatinine clearance decreased (95.5±25.9 vs 20.1±19.3 ml/min; P<0.05). After 24 h, urine output decreased from 1.4 to 0.3 ml/kg/h (P<0.05). Infusion of E. coli induced hyperdynamic sepsis and ARF. Septic ARF in this setting was associated with a marked increase in RBF and with renal vasodilatation.
Journal Article
MC3R links nutritional state to childhood growth and the timing of puberty
2021
The state of somatic energy stores in metazoans is communicated to the brain, which regulates key aspects of behaviour, growth, nutrient partitioning and development
1
. The central melanocortin system acts through melanocortin 4 receptor (MC4R) to control appetite, food intake and energy expenditure
2
. Here we present evidence that MC3R regulates the timing of sexual maturation, the rate of linear growth and the accrual of lean mass, which are all energy-sensitive processes. We found that humans who carry loss-of-function mutations in
MC3R
, including a rare homozygote individual, have a later onset of puberty. Consistent with previous findings in mice, they also had reduced linear growth, lean mass and circulating levels of IGF1. Mice lacking
Mc3r
had delayed sexual maturation and an insensitivity of reproductive cycle length to nutritional perturbation. The expression of
Mc3r
is enriched in hypothalamic neurons that control reproduction and growth, and expression increases during postnatal development in a manner that is consistent with a role in the regulation of sexual maturation. These findings suggest a bifurcating model of nutrient sensing by the central melanocortin pathway with signalling through MC4R controlling the acquisition and retention of calories, whereas signalling through MC3R primarily regulates the disposition of calories into growth, lean mass and the timing of sexual maturation.
MC3R deficiency is associated with a delay in the onset of puberty, and a reduction in growth and lean mass.
Journal Article
Diagnosis and treatment based on quantitative PCR after controlled human malaria infection
by
Langenberg, Marijke C. C.
,
Roestenberg, Meta
,
Schats, Remko
in
Adolescent
,
Adult
,
Antimalarials - therapeutic use
2016
Background
Controlled human malaria infection (CHMI) has become well-established in the evaluation of drugs and vaccines. Anti-malarial treatment is usually initiated when thick blood smears are positive by microscopy. This study explores the effects of using the more sensitive qPCR as the primary diagnostic test.
Methods
1691 diagnostic blood samples were analysed by microscopy and qPCR from 115 volunteers (55 malaria naïve and 60 having received chemoprophylaxis and sporozoite immunization) who were challenged by five mosquitoes infected with
Plasmodium falciparum
sporozoites of the NF54 strain.
Results
Retrospective analysis of different qPCR criteria for diagnosis and treatment, showed that once daily qPCR (threshold 100 parasites/ml) had 99 % sensitivity and 100 % specificity, and shortened the median prepatent period from 10.5 to 7.0 days after CHMI when compared to twice daily measurement of thick blood smears (threshold 4000 parasites/ml). This is expected to result in a 78 % decrease of adverse events before initiation of treatment in future studies. Trial outcome related to infection and protective efficacy remained unchanged.
Conclusion
The use of qPCR as the primary diagnostic test in CHMI decreases symptoms as well as parasitaemia while obviating the need for twice daily follow-up. The implementation improves safety while reducing the clinical burden and costs without compromising the evaluation of protective efficacy.
Journal Article
Changes in total and differential leukocyte counts during the clinically silent liver phase in a controlled human malaria infection in malaria-naïve Dutch volunteers
by
van Wolfswinkel, Marlies E.
,
Langenberg, Marijke C. C.
,
van Genderen, Perry J.
in
Aquatic insects
,
Atovaquone
,
Biomedical and Life Sciences
2017
Background
Both in endemic countries and in imported malaria, changes in total and differential leukocyte count during
Plasmodium falciparum
infection have been described. To study the exact dynamics of differential leukocyte counts and their ratios, they were monitored in a group of healthy non-immune volunteers in two separate Controlled Human Malaria Infection (CHMI) studies.
Methods
In two CHMI trials, CHMI-a and CHMI-b, 15 and 24 healthy malaria-naïve volunteers, respectively, were exposed to bites of infected mosquitoes, using the
P. falciparum
research strain NF54 and the novel clones NF135.C10 and NF166.C8. After mosquito bite exposure, twice-daily blood draws were taken to detect parasitaemia and to monitor the total and differential leukocyte counts. All subjects received a course of atovaquone–proguanil when meeting the treatment criteria.
Results
A total of 39 volunteers participated in the two trials. Thirty-five participants, all 15 participants in CHMI-a and 20 of the 24 volunteers in CHMI-b, developed parasitaemia. During liver stage development of the parasite, the median total leukocyte count increased from 5.5 to 6.1 × 10
9
leukocytes/L (p = 0.005), the median lymphocyte count from 1.9 to 2.2 (p = 0.001) and the monocyte count from 0.50 to 0.54 (p = 0.038). During the subsequent blood stage infection, significant changes in total and differential leukocyte counts lead to a leukocytopenia (nadir median 3.3 × 10
9
leukocytes/L, p = 0.0001), lymphocytopenia (nadir median 0.7 × 10
9
lymphocytes/L, p = 0.0001) and a borderline neutropenia (nadir median 1.5 × 10
9
neutrophils/L, p = 0.0001). The neutrophil to lymphocyte count ratio (NLCR) reached a maximum of 4.0. Significant correlations were found between parasite load and absolute lymphocyte count (p < 0.001, correlation coefficient − 0.46) and between parasite load and NLCR (p < 0.001, correlation coefficient 0.50). All parameters normalized after parasite clearance.
Conclusions
During the clinically silent liver phase of malaria, an increase of peripheral total leukocyte count and differential lymphocytes and monocytes occurs. This finding has not been described previously. This increase is followed by the appearance of parasites in the peripheral blood after 2–3 days, accompanied by a marked decrease in total leukocyte count, lymphocyte count and the neutrophil count and a rise of the NLCR.
Journal Article
Caregivers’ burden and fatigue during and after patients’ treatment with concomitant chemoradiotherapy for locally advanced head and neck cancer: a prospective, observational pilot study
by
Winette T A van der Graaf
,
Prins, Judith B
,
Simone M C H Langenberg
in
Cancer
,
Caregiver burden
,
Caregivers
2019
PurposeKnowledge of caregivers’ burden and fatigue before and after patients’ treatment for locally advanced head and neck cancer is scarce. Therefore, we aimed to explore caregivers’ fatigue and burden in relation to patients’ fatigue, distress, and quality of life.MethodsFor caregivers, burden and fatigue were assessed. For patients, fatigue severity, distress, and health-related quality of life (HRQoL) were assessed. Measurements were conducted prior to treatment, 1 week, and 3 months after chemoradiotherapy.ResultsCaregivers’ burden and fatigue followed patients’ high peak in distress, fatigue, and diminished HRQoL as a consequence of treatment. Caregivers’ baseline fatigue was a predictor for fatigue after chemoradiotherapy. Female spouses with higher baseline levels of fatigue and burden and caring for patients with lower levels of HRQoL seem risk factors for burden after chemoradiotherapy.ConclusionsAttention should be paid to caregivers’ burden and fatigue before starting patients’ intense treatment with chemoradiotherapy, as both burden and fatigue before starting treatment may contribute to burden and fatigue after chemoradiotherapy.
Journal Article
Circulating 25-hydroxyvitamin D concentration and the risk of type 2 diabetes: results from the European Prospective Investigation into Cancer (EPIC)-Norfolk cohort and updated meta-analysis of prospective studies
2012
Aims/hypothesis
Epidemiological evidence is suggestive, but limited, for an association between circulating 25-hydroxyvitamin D (25[OH]D) and risk of type 2 diabetes. We conducted a systematic review and meta-analysis that included new data from previously unpublished studies.
Methods
Using a nested case–cohort design in the European Prospective Investigation into Cancer (EPIC)-Norfolk study, we identified a random subcohort and incident type 2 diabetes cases occurring between baseline (1993–1997) and 2006. In the Ely prospective study we identified incident type 2 diabetes cases between 1990 and 2003. We conducted a systematic review of prospective studies on 25(OH)D and type 2 diabetes published in MEDLINE or EMBASE until 31 January 2012, and performed a random-effects meta-analysis combining available evidence with results from the EPIC-Norfolk and Ely studies.
Results
In EPIC-Norfolk, baseline 25(OH)D was lower among incident type 2 diabetes cases (mean [SD] 61.6 [22.4] nmol/l;
n
= 621) vs non-case subcohort participants (mean 65.3 [23.9] nmol/l;
n
= 826). There was an inverse association between baseline 25(OH)D and incident type 2 diabetes in multivariable-adjusted analyses: HR (95% CI) 0.66 (0.45, 0.97), 0.53 (0.34, 0.82), 0.50 (0.32, 0.76),
p
trend <0.001, comparing consecutive increasing 25(OH)D quartiles with the lowest. In Ely, 37 incident type 2 diabetes cases were identified among 777 participants. In meta-analysis, the combined RR of type 2 diabetes comparing the highest with lowest quartile of 25(OH)D was 0.59 (0.52, 0.67), with little heterogeneity (
I
2
= 2.7%,
p
= 0.42) between the 11 studies included (3,612 cases and 55,713 non-cases).
Conclusions/interpretation
These findings demonstrate an inverse association between circulating 25(OH)D and incident type 2 diabetes. However, causal inference should be addressed through adequately dosed randomised trials of vitamin D supplementation or genetic Mendelian randomisation experiments.
Journal Article