Assessing Human Genome-wide Variation in the Massim Region of Papua New Guinea and Implications for the Kula Trading Tradition

The Massim, a cultural region that includes the southeastern tip of mainland Papua New Guinea (PNG) and nearby PNG offshore islands, is renowned for a trading network called Kula, in which different valuable items circulate in different directions among some of the islands. Although the Massim has been a focus of anthropological investigation since the pioneering work of Malinowski in 1922, the genetic background of its inhabitants remains relatively unexplored. To characterize the Massim genomically, we generated genome-wide SNP data from 192 individuals from 15 groups spanning the entire region. Analyzing these together with comparative data, we found that all Massim individuals have variable Papuan-related (indigenous) and Austronesian-related (arriving ∼3,000 years ago) ancestries. Individuals from Rossel Island in southern Massim, speaking an isolate Papuan language, have the highest amount of a distinct Papuan ancestry. We also investigated the recent contact via sharing of identical by descent (IBD) genomic segments and found that Austronesian-related IBD tracts are widely distributed geographically, but Papuan-related tracts are shared exclusively between the PNG mainland and Massim, and between the Bismarck and Solomon Archipelagoes. Moreover, the Kula-practicing groups of the Massim show higher IBD sharing among themselves than do groups that do not participate in Kula. This higher sharing predates the formation of Kula, suggesting that extensive contact between these groups since the Austronesian settlement may have facilitated the formation of Kula. Our study provides the first comprehensive genome-wide assessment of Massim inhabitants and new insights into the fascinating Kula system.     

Untersuchungen über Keimzellenbildung und Befruchtung bei Bythinia tentaculata

Ohne Zusammenfassung     

A novel LC‐MS/MS method to quantify eumelanin and pheomelanin and their relation to UVR sensitivity – A study on human skin biopsies

Melanin in the skin can be divided into eumelanin and pheomelanin subtypes. Simultaneous quantification of these subtypes could clarify their relation to skin type and skin cancer development. We describe a novel, sensitive liquid chromatography–tandem mass spectrometry method to quantify two eumelanin markers, pyrrole‐2,3,5‐tricarboxylic acid (PTCA) and pyrrole‐2,3‐dicarboxylic acid (PDCA), and two pheomelanin markers, thiazole‐4,5‐dicarboxylic acid (TDCA) and thiazole‐2,4,5 tricarboxylic acid (TTCA), performed in a single run using the same biopsy. Volunteers with either Fitzpatrick skin type (FST) I/II or III/IV (n = 30) each provided a 4‐mm punch biopsy from the buttock. Upon analysis, the FST I + II group had significantly less of all four melanin biomarkers (PTCA, 0.75 ng/mm²; PDCA, 0.08 ng/mm²; TTCA, 0.24 ng/mm²; and TDCA, 0.10 ng/mm²) versus the FST III + IV group (PTCA, 4.89 ng/mm²; PDCA, 0.22 ng/mm²; TTCA, 2.61 ng/mm²; and TDCA, 0.72 ng/mm²), p ≤ 0.003. We find that this new LC‐MS/MS method is sensitive enough to quantify eumelanin and pheomelanin markers even in the lightest skin types.     

Development of multiple strain competitive index assays for <Emphasis Type="Italic">Listeria monocytogenes</Emphasis> using pIMC; a new site-specific integrative vector

Background  

The foodborne, gram-positive pathogen, Listeria monocytogenes, is capable of causing lethal infections in compromised individuals. In the post genomic era of L. monocytogenes research, techniques are required to identify and validate genes involved in the pathogenicity and environmental biology of the organism. The aim here was to develop a widely applicable method to tag L. monocytogenes strains, with a particular emphasis on the development of multiple strain competitive index assays.     

Patterns on the Face: The Eyebrow Flash in Crosscultural Comparison

255 instances of “brow raise” filmed in three cultures in unstaged social interactions were analyzed on different levels using the “Facial Action Coding System” (FACS, Ekman & Friesen 1978). Contraction and slackening of the M. frontalis, pars medialis et lateralis are involved, and show temporal constancy in all three cultures, creating a pattern with a typical movement configuration. This configuration is discussed as a universal prerequisite for stimulus generation perception. The total time of contraction varies with contextual features, and brow raise in openings is longer than during interactions. An analysis of co-occurrence of other facial movements showed universal patterns occurring in all three cultures. Brow raise is most often accompanied by a smile. The antithesis of this “eyebrow flash”, both in neuromuscular and semantic aspect, is brought about by the action of the M. corrugator supercilii, lowering the brows and pulling them together. In addition, a set of functional patterns could be identified in all three cultures, ranging from a factual “yes” to a “yes to social contact”. Thus, the eyebrow flash can be interpreted as a “social marking-tool” which emphasizes the meaning of other facial cues, head movements and even verbal statements.     

SCE in lymphocytes of patients treated with single, large doses of diazepam

When using the SCE test for evaluation of exposure in vivo to potential mutagens/carcinogens, it is necessary to consider possible confounding factors. In studies of possible mutagenic effects of pharmacological treatment the effect of concomitant administration of other agents such as sedatives may have to be considered. In order to assess whether diazepam per se influences SCE we have examined SCE in peripheral lymphocytes in 34 persons before and after oral administration of a single large dose of diazepam. 18 men and 16 women undergoing minor surgery of the hand received diazepam 0.2 mg kg-1 body weight orally on the day of operation, and venous blood samples were drawn on the day before the operation and again 2-5 h after the administration of diazepam. Both within cigarette smokers and non-smokers there was no statistically significant change of SCE following diazepam. It was concluded that there was no indication, from the SCE test, of an immediate mutagenic effect of a single large dose of diazepam and that such medication is not a confounding factor in studies by the SCE test.     

Molecular characterization of a new badnavirus associated with streak symptoms on enset (Ensete ventricosum,Musaceae)

Electron microscopy of leaf samples displaying streak symptoms from enset (Ensete ventricosum), a banana‐like plant widely cultivated in Ethiopia, showed the presence of bacilliform shaped virions as known for badnaviruses. DNA extracts subjected to rolling circle amplification (RCA), polymerase chain reaction (PCR) and cloning and sequence analysis revealed that the virus has a circular double‐stranded DNA genome of 7,163 nucleotides encoding predicted proteins of 21.5 kDa, 14.5 kDa and 202.5 kDa, a genome organization known for badnaviruses. The virus is phylogenetically most closely related to Sugarcane bacilliform Guadeloupe D virus with a nucleotide sequence identity of 77.2% at the conserved RT/RNase‐H region and 73.6% for the whole genome. Following the current species demarcation criteria, the virus should be considered as an isolate of a new species in the genus Badnavirus for which the name Enset leaf streak virus (ELSV) is suggested. Leaf samples from enset and banana were screened using virus‐specific primers, and ELSV was detected in six of 40 enset but not found in any of 61 banana samples. On the other hand, Banana streak OL virus (BSOLV) was detected from the majority (60%) of symptomatic banana samples but not from enset samples. This paper reports the first full‐genome sequence of a putative new badnavirus species infecting plants in the genus Ensete. In addition, this is the first report of the occurrence of BSOLV in Ethiopia.     

Evaluating potential of green alga <Emphasis Type="Italic">Chlorella vulgaris</Emphasis> to accumulate phosphorus and to fertilize nutrient-poor soil substrates for crop plants

Algae are capable of accumulating nutrients from aqueous waste, which makes them a potential fertilizer. The ability of the fast growing Chlorella vulgaris strain IPPAS C1 to accumulate phosphorus (P) was probed in V-shaped plastic foil photobioreactors. The P uptake was 0.13–0.53 g(P)·m^?2·day^?1 when the algal culture densities were kept between 0.1 and 1.0 g(DW)·L^?1 in a typical summer irradiance of Central Europe. The algal biomass can be effectively utilized for soil fertilization only if the algal cells release nutrients into the soil in a form that would be available to roots and at a rate sufficient to support plant growth. To examine this, we compared the growth of wheat, Triticum aestivum L., in two nutrient-deficient substrates: “Null Erde” and sand, with and without fertilization by wet and spray-dried algae. Plants grown in the two nutrient-deficient substrates supplemented by mineral fertilizer served as a control representing optimal nutrient supply. Plants grown in a high-nutrient substrate (SoMi 513) were used as an additional reference representing the maximum growth potential of wheat. Wheat growth was monitored for 8 weeks and measured, including the increase of the leaf area as well as shoot and root dry weight in 10 randomized replicates for each substrate and fertilization variant. After harvest, the biomass and N, P, and C contents of the plant shoots and roots were recorded. Algae fertilization of “Null Erde” led to wheat growth, including root hair production, which was similar to mineral-fertilized “Null Erde” and only slightly less vigorous than in the nutrient-rich SoMi 513 substrate. The plants grown in sand were smaller than the plants in “Null Erde” but fertilization by algae nevertheless led to growth that was comparable to mineral fertilizer. These results unambiguously demonstrate that algal biomass is a viable option for delivering nutrients to support agriculture on marginal soils.     

High-Sensitivity Fluorometry to Resolve Ion Channel Conformational Dynamics

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