14 research outputs found
Cystic echinococcosis in northern Tanzania: a pilot study in Maasai livestock-keeping communities
Background:
There are close similarities between the life-cycles of Echinococcus granulosus sensu lato (E. granulosus s.l.) that causes cystic echinococcosis (CE) in humans and Taenia multiceps/Coenurus cerebralis that causes cerebral coenurosis in small ruminants. Recent evidence highlights that livestock in Maasai communities of northern Tanzania are suffering from increases in the prevalence of cerebral coenurosis, leading to concerns about a possible concurrent increased risk of human CE. The aim of this study was to estimate the prevalence of human abdominal CE and the prevalence and species/genotypes of E. granulosus s.l. in livestock in Maasai communities.
Methods:
Human CE was diagnosed by abdominal ultrasound on volunteers agedââ„â7 years in five villages in the Longido and Ngorongoro Districts in northern Tanzania. Infection in ruminants was evaluated through inspection in local abattoirs, followed by molecular identification of one cyst per animal, with a priority for hepatic cysts, using PCR targeting of the cytochrome c oxidase I gene (COX1), followed by restriction fragment length polymorphism and multiplex PCR, and sequencing of non-E. granulosus s.l. samples.
Results:
Ultrasound was performed on 823 volunteers (n = 352 in two villages in Longido District, and n =â471 in three villages of Ngorongoro). Hepatic CE cases were diagnosed only in Ngorongoro (nâ=â6; 1.3%), of which three had active cysts. Village-level prevalence of CE ranged between 0 and 2.4%. Of the 697 ruminants inspected, 34.4% had parasitic cysts. Molecular identification was achieved for 140 of the 219 (63.9%) cysts sampled. E. granulosus s.l. and T. hydatigena/Cysticercus tenuicollis were identified in 51.4% and 48.6%, respectively, of livestock cysts. E. granulosus s.l. was identified in livestock from both Longido (35.3% of 116 genotyped cysts) and Ngorongoro (91.2% of 34 genotyped cysts). Of the total of 72 E. granuslosus s.l. cysts identified in livestock, 87.5% were E. granulosus sensu stricto (G1âG3 genotypes), 9.7% were E. ortleppi (G5) and one cyst was E. canadensis (G6â10). The three active human cysts, which were removed surgically, were G1âG3 genotypes.
Conclusions:
Multiple species/genotypes of E. granulosus s.l. are circulating in Maasai communities of northern Tanzania. Human CE was detected in villages of Ngorongoro District and a high prevalence of echinococcal cysts was observed in livestock in both districts. More precise estimation of the prevalence in this area and a better understanding of the specific risk factors for CE among Maasai communities in northern Tanzania is needed. Interventions targeting transmission routes common to both E. granulosus s.l. and T. multiceps would have dual benefits for preventing both human and livestock disease
Global, regional, and national burden of disorders affecting the nervous system, 1990â2021: a systematic analysis for the Global Burden of Disease Study 2021
BackgroundDisorders affecting the nervous system are diverse and include neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19. Previous publications from the Global Burden of Disease, Injuries, and Risk Factor Study estimated the burden of 15 neurological conditions in 2015 and 2016, but these analyses did not include neurodevelopmental disorders, as defined by the International Classification of Diseases (ICD)-11, or a subset of cases of congenital, neonatal, and infectious conditions that cause neurological damage. Here, we estimate nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021.MethodsWe estimated mortality, prevalence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs), with corresponding 95% uncertainty intervals (UIs), by age and sex in 204 countries and territories, from 1990 to 2021. We included morbidity and deaths due to neurological conditions, for which health loss is directly due to damage to the CNS or peripheral nervous system. We also isolated neurological health loss from conditions for which nervous system morbidity is a consequence, but not the primary feature, including a subset of congenital conditions (ie, chromosomal anomalies and congenital birth defects), neonatal conditions (ie, jaundice, preterm birth, and sepsis), infectious diseases (ie, COVID-19, cystic echinococcosis, malaria, syphilis, and Zika virus disease), and diabetic neuropathy. By conducting a sequela-level analysis of the health outcomes for these conditions, only cases where nervous system damage occurred were included, and YLDs were recalculated to isolate the non-fatal burden directly attributable to nervous system health loss. A comorbidity correction was used to calculate total prevalence of all conditions that affect the nervous system combined.FindingsGlobally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95% UI 378â521), affecting 3·40 billion (3·20â3·62) individuals (43·1%, 40·5â45·9 of the global population); global DALY counts attributed to these conditions increased by 18·2% (8·7â26·7) between 1990 and 2021. Age-standardised rates of deaths per 100â000 people attributed to these conditions decreased from 1990 to 2021 by 33·6% (27·6â38·8), and age-standardised rates of DALYs attributed to these conditions decreased by 27·0% (21·5â32·4). Age-standardised prevalence was almost stable, with a change of 1·5% (0·7â2·4). The ten conditions with the highest age-standardised DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.InterpretationAs the leading cause of overall disease burden in the world, with increasing global DALY counts, effective prevention, treatment, and rehabilitation strategies for disorders affecting the nervous system are needed
Renew or regress: maintaining a forum for radical entrepreneurship scholarship
No abstract available
A differential concentration-dependent effect of IVIg on neutrophil functions: relevance for anti-microbial and anti-inflammatory mechanisms
Background
Polymorphonuclear neutrophils (PMN) play a key role in host defences against invading microorganisms but can also potentiate detrimental inflammatory reactions in case of excessive or misdirected responses. Intravenous immunoglobulins (IVIg) are used to treat patients with immune deficiencies and, at higher doses, in autoimmune, allergic and systemic inflammatory disorders.
Methodology/Principal Findings
We used flow cytometry to examine the effects of IVIg on PMN functions and survival, using whole-blood conditions in order to avoid artifacts due to isolation procedures. IVIg at low concentrations induced PMN activation, as reflected by decreased L-selectin and increased CD11b expression at the PMN surface, oxidative burst enhancement, and prolonged cell survival. In contrast, IVIg at higher concentrations inhibited LPS-induced CD11b degranulation and oxidative burst priming, and counteracted LPS-induced PMN lifespan prolongation.
Conclusions/Significance
IVIg appears to have differential, concentration-dependent effects on PMN, possibly supporting the use of IVIg as either an anti-microbial or an anti-inflammatory agent
Defective functions of polymorphonuclear neutrophils in patients with common variable immunodeficiency
International audienc
Reduced Oxidative Burst by Primed Neutrophils in the Elderly Individuals Is Associated With Increased Levels of the CD16(bright)/CD62L(dim) Immunosuppressive Subset
International audienceThe aim of our study was to analyze polymorphonuclear neutrophil (PMN) functions in elderly individuals compared with those in healthy young participants, directly in whole blood to avoid issues with data interpretation related to cell isolation procedures. Despite the presence of increased circulating levels of proinflammatory cytokines, resting PMNs from the elderly individuals were not activated as shown by normal CD62L and CD11b expression at the PMN surface and normal constitutive reactive oxygen species (ROS) production. However, suboptimal stimulation induced modulations of CD62L and CD11b expression, which positively correlated with the interleukin-6 circulating level, suggesting a possible in vivo preactivation of old PMNs by this cytokine. In addition, PMN phagocytosis of opsonized Escherichia Coli was decreased in elderly individuals. Furthermore, upon preincubation of elderly whole-blood samples with tumor necrosis factor-a or Toll Receptor agonists, we observed a reduced PMN oxidative burst in response to formyl peptides. Elderly participants also exhibited an increased percentage of the immunosuppressive CD16(bright)/CD62L(dim) PMN subpopulation, which was characterized by a lower phagocytic index and a reduced ROS production compared with the CD16(bright)/CD62L(bright) subset. Thus, the reduced phagocytosis and ROS production associated with an expansion of immunosuppressive CD16(bright)/CD62L(dim) PMN subpopulation might be involved in the increased susceptibility to bacterial and fungal infections with old age
Lambda phage-based vaccine induces antitumor immunity in hepatocellular carcinoma
Background and aims: Hepatocellular carcinoma (HCC) is a difficult to treat tumor with a poor prognosis. Aspartate ÎČ-hydroxylase (ASPH) is a highly conserved enzyme overexpressed on the cell surface of both murine and human HCC cells.
Methods: We evaluated therapeutic effects of nanoparticle lambda (λ) phage vaccine constructs against ASPH expressing murine liver tumors. Mice were immunized before and after subcutaneous implantation of a syngeneic BNL HCC cell line. Antitumor actively was assessed by generation of antigen specific cellular immune responses and the identification of tumor infiltrating lymphocytes.
Results: Prophylactic and therapeutic immunization significantly delayed HCC growth and progression. ASPH-antigen specific CD4+ and CD8+ lymphocytes were identified in the spleen of tumor bearing mice and cytotoxicity was directed against ASPH expressing BNL HCC cells. Furthermore, vaccination generated antigen specific Th1 and Th2 cytokine secretion by immune cells. There was widespread necrosis with infiltration of CD3+ and CD8+ T cells in HCC tumors of λ phage vaccinated mice compared to controls. Moreover, further confirmation of anti-tumor effects on ASPH expressing tumor cell growth were obtained in another murine syngeneic vaccine model with pulmonary metastases.
Conclusions: These observations suggest that ASPH may serve as a highly antigenic target for immunotherapy
A Differential Concentration-Dependent Effect of IVIg on Neutrophil Functions: Relevance for Anti-Microbial and Anti-Inflammatory Mechanisms
IVIg at high concentrations inhibits PMN responses to LPS stimulation.
<p>Panels A, B, C and D: Effect of IVIg and F(abâČ)2 fragments on LPS modulation of adhesion molecule expression at the PMN surface. Whole-blood samples were incubated at 37°C for 15 min with PBS, IVIg (1â25 mg/ml) (panel A, C) or equimolar concentrations of F(abâČ)<sub>2</sub> (panel B, D) and then with LPS (10 ng/ml) for 30 min. Samples were then stained with PE-anti-human CD11b or anti-L-selectin as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0026469#pone-0026469-g001" target="_blank">Figure 1</a>. Results are expressed as mean fluorescence intensity (MFI). Values are means ± sem (nâ=â3). ° Significantly different from sample incubated with LPS (p<0.05). Panels E and F: Effect of IVIg and F(abâČ)<sub>2</sub> fragments on LPS priming of the PMN oxidative burst in response to formyl peptides. Whole-blood samples (500 ”l) were pre-treated with hydroethidine HE and incubated at 37°C for 15 min with PBS, IVIg (1â25 mg/ml) (panel E) or equimolar concentrations of F(abâČ)<sub>2</sub> (panel F). Samples were then incubated with LPS and fMLP as described in the legend of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0026469#pone-0026469-g001" target="_blank">Figure 1</a>. Results are expressed as mean fluorescence intensity (MFI). Values are means ± sem (nâ=â3). * Significantly different from sample incubated with LPS+fMLP (p<0.05).</p