Ultrastructure of enamel and dentine in extant dolphins (Cetacea: Delphinoidea and Inioidea)

Longitudinal and cross sections of teeth from 17 species of the Recent dolphins (Delphinoidea and Inioidea) were examined under scanning electron microscope to study the arrangement and ultrastructure of dental tissues with reference to phylogenetic and functional constraints. For most species, enamel had a simple bi-layered structure of radial enamel and an outer layer of prismless enamel. The outer prismless layer varied from 5 to 30 % of enamel thickness. The enamel of Burmeister’s porpoise (Phocoena spinipinnis) was entirely prismless. The prisms had an open sheath; tubules and tuft-like structures were common at the enamel-dentine junction. Cetacean dentine was characterized by irregularly distributed dentinal tubules in a relatively homogenous dentinal matrix. Radial enamel was observed in all Delphinoidea and in the franciscana (Pontoporia blainvillei), whereas the Amazon river dolphin (Inia geoffrensis) had prisms organized in Hunter–Schreger bands. HSB in enamel are regarded as a device for resisting propagation of cracks. These may occur due to increased functional demands, possibly related to the hardness of the species diet. Simplification in tooth shape and reduced biomechanical demands plausibly explain the primitive radial organization among delphinoids and Pontoporia. The HSB structure in the Amazon river dolphin, similar to those of extinct archaeocetes, seems to have secondary functional implications. However, the distribution of HSB in more-basal odontocetes is too poorly known to judge whether the HSB of Inia are a retained plesiomorphic feature or convergence.     

Growth characteristics of Protoheliolites norvegicus (Tabulata; Upper Ordovician; Estonia)

Protoheliolites is an early heliolitine coral characterized by closely spaced corallites separated in places by sparse coenenchyme. Growth characteristics in the type species, P. norvegicus, are revealed by detailed analysis based on serial peels and thin sections of coralla from the uppermost Katian of north‐western Estonia. Colonies of this species had a strong ability to recover from damage and partial mortality, resulting in various forms of rejuvenation, regeneration, fusion and reorganization of corallites; in some cases, this involved relatively large areas of undifferentiated soft parts. The shells of commensal cornulitids became enclosed in host coralla during colony growth. Coralla of P. norvegicus exhibit distinctive growth cycles due to responses to seasonal changes. The production of new corallites by coenenchymal increase usually occurred in low‐density bands, in which corallites generally display round to subrounded transverse outlines. In high‐density bands, the corallites became crenulated, their wall thickness increased, septal development was more pronounced, and the amount of coenenchyme increased. In addition to these cyclomorphic changes, there were significant astogenetic changes during growth. Compared with the early stage of colony development, distinctive characteristics in the late astogenetic stage include a decrease in the growth rate of the colony, better coordination among corallites, maximum development of corallite crenulations and septa in high‐density bands, more numerous coenenchymal tubules and a greater proportion of corallum area occupied by coenenchyme. In general, the role of polyps in determining morphological characteristics of individual corallites, such as tabularium area, corallite crenulations and wall thickness, was subordinate to the astogeny of the colony. Growth characteristics including colony‐wide coordination of polyp behaviour and subjugation of individuals to restore the colony following damage suggest a strong astogenetic control and high level of colony integration. Protoheliolites probably arose from a heliolitine genus rather than from a nonheliolitine group as some authors have proposed.     

Cryptosporidium hominis Infection Diagnosed by Real-Time PCR-RFLP

There are approximately 20 known species of the genus Cryptosporidium, and among these, 8 infect immunocompetent or immunocompromised humans. C. hominis and C. parvum most commonly infect humans. Differentiating between them is important for evaluating potential sources of infection. We report here the development of a simple and accurate real-time PCR-based restriction fragment length polymorphism (RFLP) method to distinguish between C. parvum and C. hominis. Using the CP2 gene as the target, we found that both Cryptosporidium species yielded 224 bp products. In the subsequent RFLP method using TaqI, 2 bands (99 and 125 bp) specific to C. hominis were detected. Using this method, we detected C. hominis infection in 1 of 21 patients with diarrhea, suggesting that this method could facilitate the detection of C. hominis infections.     

Wild plants eaten in childhood: a retrospective of Estonia in the 1970s–1990s

In this ethnobotanical study, the authors provide the first quantitative analysis of the use of wild edible plants in Estonia, describing the domains and assessing the food importance of different species. The information was collected using free‐listing written questionnaires and concerned plants used by the respondents in their childhood. As part of a major study, this article covers the responses of professionals with some botanical education at vocational or university level, to ensure the greatest possible reliability without using voucher specimens. Fifty‐eight respondents provided information on the use of 137 plant taxa, corresponding to approximately 6% of the native and naturalized vascular plants of Estonia. According to use frequency, the most typical wild food plant of Estonia is a fruit, eaten raw as a snack. The results clearly signal that the majority of famine and food shortage plants had already been forgotten by the end of the 20^th century, but new plants have been introduced as green vegetables for making salads. Despite changes in the nomenclature of the plants, the use of wild food plants in Estonia was still thriving at the turn of the 20^th century, covering many domains already forgotten in urbanized modern Europe. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 239–253.     

Historical trends in the epidemiology of candidaemia: analysis of an 11-year period in a tertiary care hospital in Brazil

Candida species are an important cause of bloodstream infections (BSI). To evaluate the epidemiological, clinical and microbiological aspects of two cohorts {1994-1999 [period 1 (P1) ]; 2000-2004 [period 2 (P2) ]} of candidaemic patients, we performed a retrospective analysis from a laboratory-based survey. A total of 388 candidaemias were identified, with an incidence of 0.20/1,000 patient-days and a significant increase in P2 vs. P1 (0.25 vs. 0.15, p = 0.04). Cancer and prior antibiotic use were frequent and Candida albicans was the most prevalent species found (42.4%). Resistance to fluconazole was found in 2.47% of the strains. No differences were observed in the species distribution of Candida during the study periods. In the P2 cohort, there were higher prevalence of elderly individuals, cardiac, pulmonary and liver diseases, renal failure, central venous catheters and antibiotic therapy. In P1, there were higher prevalence of neurological diseases and chemotherapy. The crude mortality was 55.4%. In conclusion, our incidence rates remained high. Furthermore, the distribution pattern of Candida species and the fluconazole resistance profile remained unchanged. Moreover, we found a clear trend of higher prevalence of candidaemia among the elderly and among patients with comorbidities. Finally, it is necessary to discuss strategies for the prevention and control of Candida BSI in Brazil.     

Validation of a specific prolylcarboxypeptidase activity assay and its suitability for plasma and serum measurements

Prolylcarboxypeptidase (PRCP, EC 3.4.16.2), a lysosomal carboxypeptidase, was discovered 45 years ago. However, research has been hampered by a lack of well-validated assays that are needed to measure low activities in biological samples. Two reversed-phase high-performance liquid chromatography (RP-HPLC) methods for quantifying PRCP activity in crude homogenates and plasma samples were optimized and validated. PRCP activity was determined by measuring the hydrolysis of N-benzyloxycarbonyl-l-proline (Z-Pro)-Phe. The enzymatically formed Z-Pro and Phe were measured independently under different HPLC conditions. The in-house methods showed good precision, linearity, accuracy, and specificity. Based on Michaelis–Menten constants, Z-Pro-Phe was chosen over Z-Pro-Ala as the substrate of preference. Cross-reactivity studies with dipeptidyl peptidases (DPPs) 2, 4, and 9 and prolyl oligopeptidase (PREP) confirmed the specificity of the PRCP activity assay. The average PRCP activity in plasma and serum of 32 healthy individuals was found to be 0.65 ± 0.02 and 0.72 ± 0.03 U/L, respectively. Both methods can be used to measure PRCP activity specifically in different biological samples and are well suited to evaluate PRCP inhibitors. These well-validated methods are valuable tools for studying PRCP’s role in cardiovascular diseases, stroke, inflammation, and metabolic syndrome.     

Deep Whole-Genome Sequencing of 100 Southeast Asian Malays

Whole-genome sequencing across multiple samples in a population provides an unprecedented opportunity for comprehensively characterizing the polymorphic variants in the population. Although the 1000 Genomes Project (1KGP) has offered brief insights into the value of population-level sequencing, the low coverage has compromised the ability to confidently detect rare and low-frequency variants. In addition, the composition of populations in the 1KGP is not complete, despite the fact that the study design has been extended to more than 2,500 samples from more than 20 population groups. The Malays are one of the Austronesian groups predominantly present in Southeast Asia and Oceania, and the Singapore Sequencing Malay Project (SSMP) aims to perform deep whole-genome sequencing of 100 healthy Malays. By sequencing at a minimum of 30× coverage, we have illustrated the higher sensitivity at detecting low-frequency and rare variants and the ability to investigate the presence of hotspots of functional mutations. Compared to the low-pass sequencing in the 1KGP, the deeper coverage allows more functional variants to be identified for each person. A comparison of the fidelity of genotype imputation of Malays indicated that a population-specific reference panel, such as the SSMP, outperforms a cosmopolitan panel with larger number of individuals for common SNPs. For lower-frequency (<5%) markers, a larger number of individuals might have to be whole-genome sequenced so that the accuracy currently afforded by the 1KGP can be achieved. The SSMP data are expected to be the benchmark for evaluating the value of deep population-level sequencing versus low-pass sequencing, especially in populations that are poorly represented in population-genetics studies.