Rapid assessment of regional SARS-CoV-2 community transmission through a convenience sample of healthcare workers, the Netherlands, March 2020

To rapidly assess possible community transmission in Noord-Brabant, the Netherlands, healthcare workers (HCW) with mild respiratory complaints and without epidemiological link (contact with confirmed case or visited areas with active

Episodic, mafic crust formation from 4.5 to 2.8 Ga: new evidence from detrital zircons, Slave craton, Canada

The ϵHf and δ18O values in detrital zircons from the Slave craton, Canada, indicate three episodes of crust formation between ca. 4.5 and 2.8 Ga, namely at ca. 4.4–4.5 Ga, ca. 3.8 Ga, and ca. 3.4 Ga. Most of the juvenile crust appears to have been mafic in composition, and there is no clear evidence for initial granitic protocrust in the Hadean of the Slave craton. The range of initial ϵHf values in zircons increases from 3.9 to 2.8 Ga, indicating that both extraction of new material from mantle and reworking of the older crust are important for the secular evolution of the continental crust. A preliminary review of available Hf data in zircons suggests that the three episodes of crust generation may have been of global importance. The mafic crust formed in the Archean and the Hadean was then reworked for at least ~0.5–1.5 b.y., as indicated by data from the Slave craton, Gondwana, and the Limpopo Belt of Africa

99mTc-labeled interleukin 8 for the scintigraphic detection of infection and inflammation: first clinical evaluation.

Contains fulltext : 52853.pdf (publisher's version ) (Closed access)Interleukin 8 (IL-8) is a chemotactic cytokine that binds with a high affinity to receptors expressed on neutrophils. Previous studies with various animal models showed that (99m)Tc-labeled IL-8 accumulates specifically and rapidly in infectious and inflammatory foci. The aims of the present study were to evaluate the safety of IL-8 in humans and to assess the value of (99m)Tc-IL-8 scintigraphy in patients with suspected localized infections. METHODS: (99m)Tc-IL-8 was intravenously injected at 400 MBq into 20 patients with various suspected localized infections. Patients were monitored for IL-8-related side effects for 4 h. Whole-body imaging was performed directly after injection and at 4 h after injection. Imaging after 24 h was performed for the first 7 patients and for subsequent patients when the results of (99m)Tc-IL-8 scintigraphy at 4 h after injection were normal or equivocal. Blood was drawn at several time points to determine the total number of leukocytes and leukocyte differentiation (all patients) and to determine pharmacokinetics (6 patients). RESULTS: (99m)Tc-IL-8 scintigraphy was performed for 20 patients (13 men and 7 women) with a mean age of 60 y (range, 21-76 y). No significant side effects were noted. Patients had suspected joint prosthesis infections (n = 9), osteomyelitis (n = 8), liver abscess (n = 1), and soft-tissue infections (n = 2). (99m)Tc-IL-8 was rapidly cleared from the blood and most other organs. In 10 of 12 patients with infections, (99m)Tc-IL-8 localized the infection at 4 h after injection. In 1 patient with vertebral osteomyelitis and in 1 patient with an infected knee prosthesis, (99m)Tc-IL-8 scintigraphy results were false-negative. In 8 patients with noninfectious disorders, no focal accumulation of (99m)Tc-IL-8 was found. CONCLUSION: Injection of (99m)Tc-IL-8 is well tolerated. (99m)Tc-IL-8 scintigraphy is a promising new tool for the detection of infections in patients as early as 4 h after injection

Targeted Screening for Chronic Q Fever, the Netherlands

Early detection of and treatment for chronic Q fever might prevent potentially life-threatening complications. We performed a chronic Q fever screening program in general practitioner practices in the Netherlands 10 years after a large Q fever outbreak. Thirteen general practitioner practices located in outbreak areas selected 3,419 patients who had specific underlying medical conditions, of whom 1,642 (48%) participated. Immunofluorescence assay of serum showed that 289 (18%) of 1,642 participants had a previous Coxiella burnetii infection (IgG II titer >1:64), and 9 patients were suspected of having chronic Q fever (IgG I y titer >1:512). After medical evaluation, 4 of those patients received a chronic Q fever diagnosis. The cost of screening was higher than estimated earlier, but the program was still cost-effective in certain high risk groups. Years after a large Q fever outbreak, targeted screening still detected patients with chronic Q fever and is estimated to be cost-effective

Viable coxiella burnetii induces differential cytokine responses in chronic Q fever patients compared to Heat-Killed Coxiella burnetii

Cytokine responses of chronic Q fever patients to the intracellular bacterium Coxiella burnetii have mostly been studied using ex vivo stimulation of immune cells with heat-killed C. burnetii due to the extensive measures needed to work with viable biosafety level 3 agents. Whether research with heat-killed C. burnetii can be translated to immune responses to viable C. burnetii is imperative for the interpretation of previous and future studies with heat-killed C. burnetii. Peripheral blood mononuclear cells (PBMCs) of chronic Q fever patients (n = 10) and healthy controls (n = 10) were stimulated with heat-killed or viable C. burnetii of two strains, Nine Mile and the Dutch outbreak strain 3262, for 24 h, 48 h, and 7 days in the absence or presence of serum containing anti-C. burnetii antibodies. When stimulated with viable C. burnetii, PBMCs of chronic Q fever patients and controls produced fewer proinflammatory cytokines (interleukin-6 [IL-6], tumor necrosis factor alpha, and IL-1β) after 24 h than after stimulation with heat-killed C. burnetii. In the presence of Q fever seronegative serum, IL-10 production was higher after stimulation with viable rather than heat-killed C. burnetii; however, when incubating with anti-C. burnetii antibody serum, the effect on IL-10 production was reduced. Levels of adaptive, merely T-cell-derived cytokine (gamma interferon, IL-17, and IL-22) and CXCL9 production were not different between heat-killed and viable C. burnetii stimulatory conditions. Results from previous and future research with heat-killed C. burnetii should be interpreted with caution for innate cytokines, but heat-killed C. burnetii-induced adaptive cytokine production is representative of stimulation with viable bacteria.</p

The unique Katugin rare-metal deposit (southern Siberia): Constraints on age and genesis

© 2017 Elsevier B.V. We report new geological, mineralogical, geochemical and geochronological data about the Katugin Ta-Nb-Y-Zr (REE) deposit, which is located in the Kalar Ridge of Eastern Siberia (the southern part of the Siberian Craton). All these data support a magmatic origin of the Katugin rare-metal deposit rather than the previously proposed metasomatic fault-related origin. Our research has proved the genetic relation between ores of the Katugin deposit and granites of the Katugin complex. We have studied granites of the eastern segment of the Eastern Katugin massif, including arfvedsonite, aegirine-arfvedsonite and aegirine granites. These granites belong to the peralkaline type. They are characterized by high alkali content (up to 11.8wt% Na 2 O+K 2 O), extremely high iron content (FeO * /(FeO * +MgO)=0.96-1.00), very high content of most incompatible elements - Rb, Y, Zr, Hf, Ta, Nb, Th, U, REEs (except for Eu) and F, and low concentrations of CaO, MgO, P 2 O 5 , Ba, and Sr. They demonstrate negative and CHUR-close eNd(t) values of 0.0...-1.9. We suggest that basaltic magmas of OIB type (possibly with some the crustal contamination) represent a dominant part of the granitic source. Moreover, the fluorine-enriched fluid phases could provide an additional source of the fluorine. We conclude that most of the mineralization of the Katugin ore deposit occurred during the magmatic stage of the alkaline granitic source melt. The results of detailed mineralogical studies suggest three major types of ores in the Katugin deposit: Zr mineralization, Ta-Nb-REE mineralization and aluminum fluoride mineralization. Most of the ore minerals crystallized from the silicate melt during the magmatic stage. The accessory cryolites in granites crystallized from the magmatic silicate melt enriched in fluorine. However, cryolites in large veins and lens-like bodies crystallized in the latest stage from the fluorine enriched melt. The zircons from the ores in the aegirine-arfvedsonite granite have been dated at 2055±7Ma. This age is close to the previously published 2066±6Ma zircon age of the aegirine-arfvedsonite granites, suggesting that the formation of the Katugin rare-metal deposit is genetically related to the formation of peralkaline granites. We conclude that Katugin rare-metal granites are anorogenic. They can be related to a Paleoproterozoic (~2.05Ga) mantle plume. As there is no evidence of the 2.05Ga mantle plume in other areas of southern Siberia, we suggest that the Katugin mineralization occurred on the distant allochtonous terrane, which has been accreted to Siberian Craton later