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[This corrects the article DOI: 10.1371/journal.ppat.1010268.].

Next generation sequencing has revealed the presence of numerous RNA viruses in animal reservoir hosts, including many closely related to known human pathogens. Despite their zoonotic potential, most of these viruses remain understudied due to not yet being cultured. While reverse genetic systems can facilitate virus rescue, this is often hindered by missing viral genome ends. A prime example is Lloviu virus (LLOV), an uncultured filovirus that is closely related to the highly pathogenic Ebola virus. Using minigenome systems, we complemented the missing LLOV genomic ends and identified cis-acting elements required for LLOV replication that were lacking in the published sequence. We leveraged these data to generate recombinant full-length LLOV clones and rescue infectious virus. Similar to other filoviruses, recombinant LLOV (rLLOV) forms filamentous virions and induces the formation of characteristic inclusions in the cytoplasm of the infected cells, as shown by electron microscopy. Known target cells of Ebola virus, including macrophages and hepatocytes, are permissive to rLLOV infection, suggesting that humans could be potential hosts. However, inflammatory responses in human macrophages, a hallmark of Ebola virus disease, are not induced by rLLOV. Additional tropism testing identified pneumocytes as capable of robust rLLOV and Ebola virus infection. We also used rLLOV to test antivirals targeting multiple facets of the replication cycle. Rescue of uncultured viruses of pathogenic concern represents a valuable tool in our arsenal for pandemic preparedness.

Aims To describe the drug use practices among female sex workers (FSWs) in Hanoi and to identify factors associated with their drug injecting. Design, setting and participants A two-stage cluster survey of 400 FSWs was conducted from June to September, 2002. Participating FSWs were both establishment- (160) and street-based (240), who were practising in seven urban and one suburban districts of Hanoi. Measurements Subjects were interviewed face to face using a structured questionnaire. Findings Among the middle-class FSWs, 27% used drugs, of whom 79% injected. Among low-class FSWs, 46% used drugs and 85% injected. Among drug-using FSWs, 86% had started using drugs within the past 6 years. Among drug-injecting FSWs, 81% had started injecting within the past 4 years. Cleaning of injecting equipment was not common among those who shared. Having drug-injecting 'love mates', drug-using clients, longer residence in Hanoi, more clients and not currently cohabiting were found to be independently associated with drug injecting among FSWs. Conclusions The high prevalence of injecting drug use among FSWs makes them susceptible to HIV infection, and is a threat to their clients. There is a strong relationship between drug-using FSWs and male drug-using clients and non-client partners. Intervention to prevent drug use initiation among non-drug-using FSWs and harm reduction among drug-using FSWs are urgently needed.

R-phycoerythrin has been widely used in food, cosmetic, pharmaceutical, and analytical reagent industries. The present work reports an effective procedure for the extraction of R-phycoerythrin from Gracilaria gracilis. Firstly, the algae pre-treatment is a significant stage, and the highly effective extraction of R-phycoerythrin from G. gracilis was carried out with freeze-dried seaweed and grinding with liquid nitrogen. Secondly, two different methods for the extraction of this pigment were tested: (i) by using the extraction solutions (tap water, pure water, phosphate buffer 100 mM with pH 6.5, and phosphate buffer 20 mM with pH 7.1); and (ii) by using polysaccharide-degrading enzymes (xylanase, cellulase, and β-glucanase). Cellulase enhanced the extraction yield of R-phycoerythrin from G. gracilis (12.76 mg g-1 dw). Finally, under the optimal hydrolysis conditions obtained with cellulase according to a response surface methodology study of temperature (32°C), hydrolysis time (286 min), and enzyme/dry seaweed ratio (47 mg g-1), maximum yield of R-phycoerythrin (15.75 mg g-1 dw) was obtained. [ABSTRACT FROM AUTHOR]

Roselle (Hibiscus sabdariffa L.) seed is a valuable food resource owning to its high amount of nutrition such as protein, edible oil and fiber. Hence, this study researched on the application of roselle seed in a cookie product. Roselle seed was pre-treated turning into roselle seed powder without shell (RSP). To enhance the yield and soluble capacity of RSP, maltodextrin was used as supplement in RSP. Study was estimated the content of RSP was replaced to wheat flour in cookie's recipe, the physical quality of dough and cookie was carried out. Nutrition value and sensory quality of cookie were also examined. Result was compared to control cookie (without RSP replaced), which was result of the supplement of maltodextrin value in RSP was 20% (RSP20) and 30% of RSP20 was replaced of wheat flour in cookie's recipe. Compared to the dough and the cookie control, the dough with 30% of RSP20 replaced was significantly stickier and low in the hardness, adhesiveness and springiness. In overall acceptance, the cookie with 30% RSP20 scored the highest (7.01) among other formulations. The quality of cookie also showed a higher content of protein (9.51g/ 100g), lipid (23.8g/ 100g), total dietary fiber (1.25g/ 100 g) and improved its antioxidant activity with a higher total phenolic content (1.91 mgGAE/g cookie) and stronger radical scavenging capacity (73.98%). [ABSTRACT FROM AUTHOR]

In an effort to develop a Standard Reference Material (SRM) for Seebeck coefficient, we have conducted a round-robin measurement survey of two candidate materials--undoped Bi2Te3 and Constantan (55 % Cu and 45 % Ni alloy). Measurements were performed in two rounds by twelve laboratories involved in active thermoelectric research using a number of different commercial and custom-built measurement systems and techniques. In this paper we report the detailed statistical analyses on the interlaboratory measurement results and the statistical methodology for analysis of irregularly sampled measurement curves in the interlaboratory study setting. Based on these results, we have selected Bi2Te3 as the prototype standard material. Once available, this SRM will be useful for future interlaboratory data comparison and instrument calibrations. [ABSTRACT FROM AUTHOR]

The purinergic receptor system plays an important role in the regulation of both vascular and tubular functions within the kidney; however, the release of purinergic agonists other than ATP by renal tissue is not known. In this investigation, we determine if kidney tissue is a source of diadenosine polyphosphates, which have high affinity for the P2X and P2Y receptors. Both diadenosine pentaphosphate and hexaphosphate were identified by matrix-assisted laser desorption ionization–mass spectrometry in extracts purified from both whole porcine kidney and from cloned cells of the LLC-PK1 cell line. Both polyphosphates in nanomolar concentrations were found to significantly stimulate the proliferation of vascular smooth muscle cells derived from rat thoracic aortas. The purinergic-receptor antagonist, suramin, did not significantly affect the growth-stimulatory properties of the polyphosphates. The growth stimulation of vascular smooth muscle cells by platelet-derived growth factor was potentiated by both diadenosine polyphosphates. We conclude that diadenosine polyphosphates are endogenous purinergic agonists of the kidney that have physiologic and pathophysiologic relevance. These epithelial cell metabolic products have vasoregulatory properties while linking the energy supply and tubular function.Kidney International (2007) 71, 994–1000. doi:10.1038/sj.ki.5002186; published online 14 March 2007 [ABSTRACT FROM AUTHOR]

We performed a retrospective review in both comprehensive stroke units of a region affected early by the coronavirus disease 2019 (COVID-19) pandemic, between March 1 and April 26, 2020, including patients with COVID-19 who underwent mechanical thrombectomy for ischemic stroke. We identified 13 cases, representing 38.2% of 34 thrombectomies performed during this period. We observed increased mortality and a high incidence of thrombotic complications during hospitalization. Given the high rate of infected patients, systematic use of full personal protection measures seems justified., (© 2020 by American Journal of Neuroradiology.)

The essential fatty acid 22:6(n-3) is a minor component of the Western diet, but a major fatty acid in human testis and semen. In mature spermatozoa, the physical and fusogenic properties of the plasma membrane are probably influenced by its particular fatty acid composition. In this study, the synthesis of 22:6(n-3) and 22:5(n-6) was investigated in isolated human testicular cells. [1-(14)C]20:4(n-6), [1-(14)C]20:5(n-3), [1-(14)C]22:4(n-6) and [1-(14)C]22:5(n-3) were incubated in a 'crude' cell suspension (consisting of a mixture of the cells in the seminiferous tubule), and in fractionated pachytene spermatocytes and round spermatids. The esterification of fatty acids in lipid and phospholipid classes and the fatty acid chain elongation and desaturation were measured. The crude cell suspension metabolized the fatty acids more actively than did the fractionated germ cell suspension, indicating that types of cell other than the germ cells are important for fatty acid elongation and desaturation and thus the production of 22:6(n-3). This finding is in agreement with previous results in rats that indicated that the Sertoli cells are the most important type of cell for the metabolism of essential fatty acids in the testis. Some [1-(14)C]20:5(n-3) was elongated to [(14)C]22:5(n-3) in the fractionated germ cells, but very little was elongated further to [(14)C]24:5(n-3),possibly restricting the formation of [(14)C]22:6(n-3). In the fractionated germ cells, the fatty acid substrates were recovered primarily in the phospholipid fraction, indicating an incorporation in the membranes, whereas in the crude cells, more substrates were esterified in the triacylglycerol fraction. In the phospholipids, more radioactivity was recovered in phosphatidylcholine than in phosphatidylethanolamine and more radioactivity was recovered in phosphatidylethanolamine than in phosphatidylinositol or phosphatidylserine.

Arbitrarily primed PCR (AP-PCR) is a unique method to identify the cancer cell specific losses and gains of chromosomal regions by targeting specific genes or chromosomal segments. In the present study, introducing the AP-PCR technique with a single primer, we have ascertained the gains and losses of DNA fingerprints in 15 MALT lymphoma samples. Out of 15 prominent DNA fingerprints, the signal intensity of two fingerprints, labeled bands G and I, were significantly lower in 40 and 50% of tumors as compared to adjacent normal DNA fingerprints, respectively. Similarly, gains of signal intensity of DNA fingerprints (bands A and C) were detected in 13% of tumor samples studied. Variations in signal intensities were also found in other bands within a few samples. Although, the functional importance of these bands is unknown, this study indicates that the AP-PCR generated under or over amplified DNA fingerprints may participate during the progression of MALT lymphoma in human stomach. Moreover, these studies also suggest that the AP-PCR technique, with different primers, can be utilized for the determination of new chromosomal segments in MALT lymphoma samples that can be used for the identification of these diseases.

Dengue shock syndrome (DSS) is a potentially lethal complication of dengue virus infection associated with hypotension and leakage of plasma water into the extravascular space. To determine whether the underlying pathophysiology of DSS is distinct from that in milder forms of the disease, we assessed microvascular permeability, by use of strain gauge plethysmography, in Vietnamese children with DSS (n=19), or dengue hemorrhagic fever (DHF) without shock (n=16), and in healthy control children (n=15). At admission and after fluid resuscitation, the mean coefficient of microvascular permeability (K(f)) for the patients with dengue was approximately 50% higher than that for the control patients (P=.02). There was no significant difference in K(f) between the 2 groups of patients with dengue; this suggests the same underlying pathophysiology. We hypothesize that in patients with DSS, the fluctuations in K(f) are larger than those in patients with DHF, which leads to short-lived peaks of markedly increased microvascular permeability and consequent hemodynamic shock.

The possibility that serum ferritin is a secreted protein and an acute phase reactant regulated by inflammatory hormones and iron was examined in a hepatic cell line that secretes plasma proteins. Differentiated rat hepatoma cells released albumin and ferritin into the medium, as determined by rocket immunoelectrophoresis and isolation of ferritin by standard procedures plus immunoaffinity chromatography, following labeling with radioactive amino acid. Administration of interleukin-1-beta (IL-1) or tumor necrosis factor-alpha (TNF) doubled the amounts of ferritin released into the medium over 24 and 48 hours. Together, the cytokines had more than an additive effect. Albumin secretion was diminished by IL-1, but not TNF. Iron, administered as an iron dextran complex or as a 1:1 chelate with nitrilotriacetate (Fe-NTA), also enhanced ferritin release, but had no effect on albumin. Intracellular ferritin concentrations did not change significantly with cytokine treatment, but increased in response to iron. With or without treatments, release of ferritin and albumin from cells into the medium was inhibited by brefeldin A, an inhibitor of Golgi function. The effect of each of the cytokines and of iron on ferritin and albumin was also blocked by dichlorofuranosylbenzimidazole (DRB), an inhibitor of transcription. The stimulatory effect of Fe-NTA on ferritin secretion was diminished by TNF, and this was partially counteracted by IL-1, indicating additional regulatory complexity. These results show for the first time that hepatic cells secrete ferritin, that this ferritin secretion is regulated by iron and inflammatory cytokines, and that the mechanisms of regulation differ from those for intracellular ferritin. The results would explain why serum ferritin increases in inflammation or when iron flux is enhanced.