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The planktonic rotifer Brachionus calyciflorus was reported to have a behavioral response to the predatory rotifer Asplanchna , where individuals move up to a surface-film refuge. Here, I re-examine this response and also test the hypothesis that Asplanchna affects the propensity of B. calyciflorus to attach to glass surfaces. In eight experiments where B. calyciflorus was exposed to a strong Asplanchna stimulus for periods varying from 3 to 65 h, adults and juveniles showed no increase in propensity to settle at the surface film or to attach to glass surfaces. In treatments with and without Asplanchna , percentages of Brachionus free-swimming, attached to glass or settled at the surface film were 81–100%, 0–18% and 0–3%, respectively. Three types of defensive responses in planktonic rotifers are reviewed: (1) transgenerational, spine-development responses to the Asplanchna kairomone in many brachionids; (2) slow-onset (4–48 h) increases in attachment propensity due to Asplanchna , or just its kairomone, in the facultatively epizoic Brachionus rubens and Brachionus variabilis and in an attachment-prone clone of Brachionus dorcas (B. calyciflorus species complex) and (3) brief escape movements caused by disturbance immediately after contact or near-contact with various predators (Asplanchna , Daphnia , copepods) in Filinia , Keratella , Hexarthra and Polyarthra. [ABSTRACT FROM AUTHOR]

The prevalence of new psychoactive substances (NPS) on the illicit drug market continues to grow, with new analogs being routinely synthesized. Routes of administration for these compounds are also diversifying, and recent research has shown an increase in the incorporation of NPS into vaping liquids. Among the most commonly encountered NPS are the cathinone and fentanyl analogs. Fentanyl analogs in particular have been implicated in a significant number of deaths, usually in combination with other prescription and illicit drugs. We report the case of a 44-year-old male with a history of polysubstance abuse found deceased at his home address. Items located within the vicinity of the deceased were found to contain furanylfentanyl and 2-methyl-4'-(methylthio)-2-morpholinopropiophenone (MMMP also known as MTMP, MMTMP, Irgacure 907 and Caccure 907). Both of these compounds were detected in the post-mortem peripheral blood of the deceased: furanylfentanyl at 1.6 ng/mL and MMMP at 6.7 ng/mL. MMMP is an unrestricted, commercially available photo-initiator used in the printing and polymer industry, which structurally can be classed as a highly modified cathinone. Although MMMP has been found previously in drug seizures, this is the first fatality in which MMMP has been detected. A number of other prescription and illicit drugs were also detected in the blood. MMMP was not detected in the post-mortem urine; however three metabolites, beta-hydroxy-MMMP, beta-hydroxy-MMMP-sulfoxide and beta-hydroxy-MMMP-sulfone, were presumptively identified. The significance of MMMP to the cause of death is uncertain as its pharmacological and toxicological profile is unclear. [ABSTRACT FROM AUTHOR]

Twenty-six phase III studies on Alzheimer's disease are ongoing or have been completed in 2018. Most of these studies are targeting amyloid-beta, its production, polymerization, and/or multiple interactions. None of the amyloid-beta studies seem to affect positively the clinical outcome of patients with Alzheimer's disease thus far, no matter the advancement of disease. It is time to consider other hypotheses for the pathogenesis of Alzheimer's disease, including the potential role of human herpes viruses (HHV), and especially HHV1 (herpes simplex virus type 1), HHV3 (varicella zoster virus), HHV6A, and HHV7. With this perspective, we review the scientific evidence and make the case for appropriately powered, prospective, randomized, and controlled studies using an anti-HHV drug, to establish a causal role for HHV in Alzheimer's disease. [ABSTRACT FROM AUTHOR]

The planktonic rotifer, Brachionus calyciflorus, displays extensive variation in the length of its anterior and posterior spines. Notably, posterolateral spines may be absent or near body length. Studies of laboratory and natural populations have identified the different factors controlling this variation and have investigated the trade-offs associated with increased spine development. Low temperature and low food availability can induce modest spine elongation that may reduce sinking rate. A kairomone released by the carnivorous rotifer Asplanchna induces pronounced spine elongation, without detectable reproductive cost, that can provide an effective defense against this predator. Endogenous mechanisms also operate: Spine development is inhibited in females hatched from fertilized resting eggs and can be promoted by increasing maternal age. Genetic variation for the length of spines in both noninduced (default) and induced phenotypes occurs among and within populations. Asplanchna in natural communities likely leads to seasonal selection for genotypes that can develop increasingly long spines. [ABSTRACT FROM AUTHOR]

Two morphologically distinct Brachionus calyciflorus hatched from Lake Littra sediment: a typical B. calyciflorus Pallas and B. (calyciflorus) "Darling", a reproductively isolated, globular taxon without posteromedian spines. The Darling taxon is well defended against Asplanchna by its large size (adult lorica length ≥ 310 μm) and short (~50 μm) Asplanchna-induced posterior spines that protect small, vulnerable neonates. The typical B. calyciflorus is smaller (adult lorica length 169-195 μm) and is a mixture of interbreeding clones with or without constitutive posterolateral spines. In one of the former clones, adult posterolateral spine length increased significantly with maternal age, from ~62 to 78 μm. Asplanchna induced increased lorica length and pronounced spine development in all clones and its effect on females with constitutive posterolateral spines was additive. With Asplanchna, posterolateral spine length was 159 μm for a clone without constitutive posterolateral spines and 207 μm in a clone with 74μm-long constitutive posterolateral spines. Coexistence of clones with and without constitutive posterolateral spines suggests a trade-off between the benefit of long defensive spines and some cost to spine development. It likely is maintained by fluctuating directional selection in response to changing Asplanchna abundance and by a sediment bank of diapausing eggs produced by sexual reproduction. [ABSTRACT FROM AUTHOR]

Brachionus variabilis, a facultative epibiont on cladocerans, has a pronounced morphological response to Asplanchna. Adult amictic females of the Asplanchna-induced morph, compared with those of the basic or non-induced morph, had a 13% larger lorica, 150% longer posterior spines and 30–40% longer anterior spines. Similar responses occur in many other brachionid rotifers as an effective defense against Asplanchna predation, but the response of B. variabilis is surprising. The large size and epizoic habit of B. variabilis should provide good protection against this predator. Also, a smaller epizoic congener (Brachionus rubens) readily ingested by Asplanchna has no morphological response to it. Brachionus variabilis also has a pronounced behavioral response to Asplanchna. Without Asplanchna, most individuals are actively swimming, with only a small proportion of them attached to surfaces. With Asplanchna, the proportion of attached individuals is much higher. Significant attachment responses in both young and adult individuals occurred shortly (∼5 h) after exposure to live Asplanchna (three experiments) or to its kairomone (five experiments), but not to a Daphnia kairomone. The Asplanchna-enhanced propensity for attachment to surfaces, possibly including cladoceran hosts, may be an additional defense against this predator. This is the first report of a predator kairomone inducing a behavioral shift in a rotifer. [ABSTRACT FROM PUBLISHER]

In many small planktonic rotifers, predator kairomones induce the development of longer spines, which can provide effective post-contact defense against the predators. This review briefly discusses potential trade-offs associated with pronounced spine development, focuses on an evaluation and synthesis of experimental work comparing the reproductive potential of basic (non-induced) and Asplanchna-induced morphs and suggests areas for future research. To date, the only convincing evidence for an association between induced spine development and reduced reproduction is for Keratella testudo. This rotifer has a dense lorica (skeleton), so that elongated spines increase its sinking rate and thus presumably an offsetting swimming effort. In contrast, several studies with Brachionus calyciflorus and Keratella tropica, which have a thin lorica, showed that morphs with pronounced spine development reproduced at the same rate as basic morphs. In other studies with several different species, and also with B. calyciflorus, the presence of Asplanchna did inhibit reproduction. However, this inhibition generally was not clearly related to Asplanchna density or the degree of spine development, and could not be attributed to a defense cost. While predator-induced morphs of some species do not have a reduced reproductive potential in the laboratory, they may be at a disadvantage in certain interactions or conditions occurring in more complex, natural ecosystems. Such environmental costs, or plasticity costs resulting from the evolution of mechanisms for detecting and responding to predators, may explain why long spines in some rotifers are an inducible rather than a constitutive defense. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study that compares the liquid chromatography-tandem mass spectrometry (LC/MS/MS) method and a method using acetonitrile extraction and subsequent immunoaffinity column (IAC) cleanup. The study shows poor performance of the method without cleanup than the method with IAC cleanup in terms of identification based on ion ratios. Also, repeatability was poor with no cleanup.

Evaluates the effectiveness of an immunoaffinity column cleanup liquid chromatography method for determination of aflatoxin Bi and total aflatoxins in hazelnut paste at European regulatory limits. Removal of aflatoxins from the immunoaffinity column with methanol; Quantification by reversed-phase LC with post-column derivatization involving bromination; Relative standard deviation for repeatability for aflatoxin.

Indirect evidence from observations in the field suggested that a common and often abundant cyclopoid copepod, Tropocyclops extensus, despite its small size (0.5 mm) and largely algal diet, is an important predator of the rotifer Polyarthra remata. Laboratory experiments showed that copepodids and adults, but not nauplii, markedly suppressed the population growth of this rotifer. The suppression could be attributed entirely to predation, rather than to exploitative competition for shared food resources or to interference. Mortality rates predicted from a separate feeding-rate experiment weresufficient to account for the decline in population size observed in the Tropocyclops treatment of culture experiments. Also, monitoring the availability of cryptomonad food in treatments with and without Tropocyclops throughout these experiments showed that cryptomonad densities always remained high and were just as high or significantly higher in the copepod treatments. Furthermore, direct videographic observations of P. remata from cultures with and without Tropocyclops demonstrated no significant differences in swimming velocity, tendency to deviate from a straight-line path, or frequency and length of spontaneous escape responses. Per capita ingestion rates of T. extensus on P. remata varied from 2 to 8 day−1, were significantly higher for adult females than adult males or copepodids V, and increased significantly with rotifer density. A tendency of copepods to have higher ingestion rates on young than adult rotifers was not significant. Copepods cultured since birth with cryptomonads and P. remata ate significantly fewer rotifers than those cultured only with cryptomonads; this may be explained by a more sated condition of the former and provided no evidence for the idea that previous experience with this rotifer might increase predation efficiency. The results show that T. extensus in natural communities has the potential to deplete natural populations of susceptible rotifer prey. Accordingly, it may shift the species structure of rotifer assemblages in favour of resistant species, and provide selection pressure for avoidance responses. [ABSTRACT FROM PUBLISHER]

Examines the contribution of the germline variants of the APC genes to patients with colorectal tumors. Proportion of multiple adenoma patients with disease resulting from germline APC variants; Association of E1317Q APC variant with multiple colorectal adenomas; Role of germline APC variants in truncating mutations 5 to exon 5, in exon 9 and 3 to codon 1580.

SYNOPSIS. The class Rotifera includes species which reproduce solely by apomictic female parthenogenesis and species which alternate this “asexual” reproduction with ordinary sexual reproduction. The transition between asexual and sexual reproduction is controlled by the environment. Laboratory studies with the genus Asplanchna have shown that it is possible to identify specific molecules as inducers, which act on embryos in utero to modify their development and determine whether they will mature as sexually or asexually reproducing females. Moreover, an evolutionary rationale can be provided for the response to these particular environmental controlling agents, which are such that sexual reproduction will occur only when it will result in successful fertilization. Rotifers are opportunistic or colonising organisms, which implies selection for rapid reproduction. We suggest that this may account, at least in part, for the origin of both apomicitc parthenogenesis and certain features of the pattern of macromolecular syntheses during development. To account for the success of those rotifers which have lost sexual reproduction entirely, we note that accumulation of mutations during periods of exponential apomictic parthenogenetic reproduction, together with “mitotic” crossing-over, could theoretically produce sufficient genotypic diversity to provide evolutionary flexibility. This would eliminate a major advantage of sexual reproduction. [ABSTRACT FROM PUBLISHER]

A letter to the editor is presented in response to the article "Are Spirituality and Religiosity Resources for Patients with Chronic Pain Conditions?," by A. Büssing, A. Michalsen, H-J Balzat, R. A. Grünther, T. Ostermann, E. A. M. Neugebauer, and P. F. Mathiessen in the October 2009 issue is presented.

A letter to the editor is presented in response to the article "God Image and Happiness in Chronic Pain Patients: The Mediating Role of Disease Interpretation," by Dezutter and colleagues in the 2010 issue.