Caelius Aurelianus‘ textbook on medicine of the fifth century: rhythm in asthma,pain, and drug effects

Caelius Aurelianus was a Greek-Roman physician in the fifth century. He translated the work of Soranus from Ephesus into Latin and extended the medical knowledge of his time in several textbooks. His book “De Morbis acutis et chronicis” was reprinted many times up to the 19th century and served as the handbook for physicians. Aurelianus aready described in detail the rhythmic pattern – daily and seasonally – of asthma. Tooth pain was also first described by Caelius Aurelianus to peak at night and that drugs were not able to fully suppress the pain, a first indication of chronopharmacology.     

Wear Behavior of Plasma Oxidized CoCrMo Alloy under Dry and Simulated Body Fluid Conditions

In this study, CoCrMo alloy was oxidized in plasma environment at the temperatures of 600 ℃ to 800 ℃ for 1 h to 5 h with 100% 02 gas and its tribological behavior was investigated. After the plasma oxidizing process, the compound and diffusion layers were formed on the surface. XRD results show that Cr203, a-Co and ε-Co phases diffracted from the modified layers after plasma oxidizing. The untreated and treated CoCrMo samples were subjected to wear tests both in dry and simulated body fluid conditions, and normal loads of 2 N and 10 N were used. For the sliding wear test, alumina balls were used as counter materials. It was observed that the wear resistance of CoCrMo alloy was increased after the plasma oxidizing process. The lowest wear rate was obtained from the samples that were oxidized at 800 ℃ for 5 h. It was detected that both wear environment and load have significant effects on the wear behavior of this alloy, and the wear resistance of oxidized CoCrMo alloy is higher when oxide-based counterface is used. The wear rates of both untreated and plasma oxidized samples increase under high loads.     

Feather‐degrading bacteria,uropygial gland size and feather quality in House Sparrows Passer domesticus

Feathers are dead integumentary structures that are prone to damage and thus show gradual degradation over the course of a year. This loss of quality might have negative fitness consequences. Feather‐degrading bacteria are some of the most prevalent feather‐degrading organisms, yet the relationship between feather‐degrading bacteria load and flight feather quality has rarely been assessed. We studied this relationship in free‐living House Sparrows during breeding and non‐breeding annual lifecycle stages. We also considered the size of the uropygial gland, given the antimicrobial function of its secretions, and the effect of body condition. The number of feather holes was positively associated with feather‐degrading bacteria load and was negatively related to uropygial gland size and body condition during the breeding season in both sexes. In the non‐breeding season we found the same relationships, but only in females. The degree of feather wear was unrelated to any of the variables measured during the breeding season, whereas it was negatively associated with uropygial gland size and positively with feather‐degrading bacteria load in the non‐breeding season, but only in females. Our results suggest that feather‐degrading bacteria may induce the formation of feather holes, but play only a minor role in the abrasion of flight feathers.     

原花青素对磷酸三钙磨损颗粒所致小鼠颅骨溶解的干预作用及其机制

目的:研究原花青素对磷酸三钙(TCP)磨损颗粒诱导小鼠颅骨溶解的保护作用,并探讨其机制。方法:48只雄性ICR小鼠,随机分为假手术(Sham)组、TCP磨损颗粒(TCP)组、原花青素(0.2mg/kg,1mg/kg,5mg/kg)组,每组12只。将TCP磨损颗粒30mg包埋于小鼠颅骨顶部构建假体周围模型,于术后第2日颅顶局部注射原花青素,隔日1次。2周后处死小鼠采血、取颅骨。抗酒石酸酸性磷酸酶(TRAP)染色和HE染色观察假体周围骨溶解和破骨细胞生成情况;实时荧光定量PCR检测假体周围骨组织中破骨细胞调控基因TRAP、capthesinK、c-Fos和NFATc1的mRNA水平;化学比色法检测血清中丙二醛(MDA)和总抗氧化能力(T-AOC)含量及超氧化物歧化酶(SOD)活性;Westernblot法检测小鼠假体周围骨组织中自噬标志蛋白Beclin-1和微管相关蛋白1轻链3(LC-3)表达变化。结果:与Sham组比较,TCP组假体周围骨溶解面积、破骨细胞生成及其调控基因mRNA水平显著增加(P<0.05),血清MDA含量均明显升高、T-AOC水平和SOD活性明显降低(P<0.05),假体周围骨组织中Beclin-1和LC-3均表达显著上调、LC-3I向LC-3II转换明显增加(P<0.05)。与TCP组比较,原花青素组假体周围骨溶解面积、破骨细胞生成及其上述调控基因、血清MDA含量明显减少(P<0.05),血清T-AOC含量和SOD活性显著增加(P<0.05)且Beclin-1和LC-3等蛋白表达及LC-3I向LC-3II转换也明显下调。结论:原花青素对TCP磨损颗粒所致的假体周围骨溶解具有明显保护作用,其机制可能与减轻氧化应激反应和自噬的活化密切相关。     

Induction of human keratinocytes into enamel-secreting ameloblasts

Mammalian tooth development relies heavily on the reciprocal and sequential interactions between cranial neural crest-derived mesenchymal cells and stomadial epithelium. During mouse tooth development, odontogenic potential, that is, the capability to direct an adjacent tissue to form a tooth, resides in dental epithelium initially, and shifts subsequently to dental mesenchyme. Recent studies have shown that mouse embryonic dental epithelium possessing odontogenic potential is able to induce the formation of a bioengineered tooth crown when confronted with postnatal mesenchymal stem cells of various sources. Despite many attempts, however, postnatal stem cells have not been used successfully as the epithelial component in the generation of a bioengineered tooth. We show here that epithelial sheets of cultured human keratinocytes, when recombined with mouse embryonic dental mesenchyme, are able to support tooth formation. Most significantly, human keratinocytes, recombined with mouse embryonic dental mesenchyme in the presence of exogenous FGF8, are induced to express the dental epithelial marker PITX2 and differentiate into enamel-secreting ameloblasts that develop a human-mouse chimeric whole tooth crown. We conclude that in the presence of appropriate odontogenic signals, human keratinocytes can be induced to become odontogenic competent; and that these are capable of participating in tooth crown morphogenesis and differentiating into ameloblasts. Our studies identify human keratinocytes as a potential cell source for in vitro generation of bioengineered teeth that may be used in replacement therapy.     

Regional impacts of global climate change: a local humid phase in central Iberia in a late Miocene drying world

The end of the Miocene was an eventful period of changes in climate and geography, and a restructuring of terrestrial plant and mammals. The tendency towards global aridification has attracted much recent interest, making the late Miocene a striking case‐study for testing current and near‐future scenarios involving global warming. Little is known about the consequences of global changes in temperature and precipitation at regional or local scales. Given its geographical position and extraordinary fossil record, the Iberian Peninsula offers many insights into short‐ and long‐term shifts in climate, and the local response. Here, we explore the diet and ecology of large‐mammals through tooth‐wear patterns, and examine changes in local climate and habitat conditions in central Spain in a period (9.1–6.3 Ma) for which there exists a dearth of palaeoenvironmental information. Relatively dry climates and open‐woodland landscapes evolved locally during the late Vallesian and early Turolian (9.0–7.7 Ma). Unexpectedly, we detect a period of high precipitation and a peak of humidity at the end of the Turolian (7.0 Ma) that prompted the development of wetter, more forested habitats, suggesting that the traditional view of the late Miocene as a steppe landscape is a misconception. We also find a period of relatively drier and warmer conditions from the early Ventian onwards. Overall, our finding that a local episode of increased humidity in central Spain was synchronous with a global warming trend in Europe provides evidence that the greatest climatic changes may have an opposite impact at regional and local scales.     

Criteria for assessing maturity of skulls in the common dolphin,Delphinus sp., from New Zealand waters

Knowledge about the maturity status of specimens included in evolutionary, taxonomic or life history investigations is fundamentally important. This study investigated the use of the degree of cranial suture fusion, the developmental status of cranial bones, and the degree of tooth wear as indicators for cranial maturity status in Delphinus sp. from New Zealand waters. In total, 15 sutures, one joint and three nonmetric characters were assessed on 66 skulls obtained from stranded and bycaught individuals sampled between 1932 and 2011. A suture index (SI) was computed based on 10 sutures, in which degree of fusion was correlated with age and the three misclassification indices (MI), calculated for a given suture, were <50%. In addition to these, five premaxilla‐maxilla fusion and seven tooth wear categories were assessed. Results suggest that New Zealand Delphinus sp. skulls should be regarded as cranially mature if at least two of the following criteria are met: (1) individuals assessed as sexually mature, (2) aged ≥ 11 yr, (3) SI ≥ 8, and (4) premaxilla‐maxilla fusion ≥ 75% of the length of the dorsal side of the rostrum. Presence of any number of rostral teeth worn to the gum line provided further evidence for cranial maturity.