Rare Trait Research Articles

Papillon-Lefevre Syndrome-A Report of Two Cases

Papillon-Lefevre syndrome is a rare autosomal recessive trait characterised by palmoplantar hyperkeratosis and precocious loss of both deciduous and permanent teeth. The aetiology is multifactorial with genetic, immunological, microbiological factors being considered a main etiopathogenic factors. We present here two cases of two siblings affected with Papillon-Lefevre syndrome.

Glucose Metabolism via the Entner-Doudoroff Pathway in Campylobacter: A Rare Trait that Enhances Survival and Promotes Biofilm Formation in Some Isolates.

Isolates of the zoonotic pathogen Campylobacter are generally considered to be unable to metabolize glucose due to lack of key glycolytic enzymes. However, the Entner-Doudoroff (ED) pathway has been identified in Campylobacter jejuni subsp. doylei and a few C. coli isolates. A systematic search for ED pathway genes in a wide range of Campylobacter isolates and in the C. jejuni/coli PubMLST database revealed that 1.7% of >6,000 genomes encoded a complete ED pathway, including both C. jejuni and C. coli from diverse clinical, environmental and animal sources. In rich media, glucose significantly enhanced stationary phase survival of a set of ED-positive C. coli isolates. Unexpectedly, glucose massively promoted floating biofilm formation in some of these ED-positive isolates. Metabolic profiling by gas chromatography–mass spectrometry revealed distinct responses to glucose in a low biofilm strain (CV1257) compared to a high biofilm strain (B13117), consistent with preferential diversion of hexose-6-phosphate to polysaccharide in B13117. We conclude that while the ED pathway is rare amongst Campylobacter isolates causing human disease (the majority of which would be of agricultural origin), some glucose-utilizing isolates exhibit specific fitness advantages, including stationary-phase survival and biofilm production, highlighting key physiological benefits of this pathway in addition to energy conservation.

Os parietale partitum: Exploring the prevalence of this trait in four contemporary populations

Os parietale partitum is a variable segmentation of the parietal bone. This manifests as a parietal division in the anteroposterior or superoinferior planes that is separated by an unusual suture and can be complete or incomplete. The existence of parietal divisions was observed and documented more than 260 years ago. The main objectives of this paper are to record the incidence of this rare trait in four modern populations with no previous records of it and provide a review of the literature. Four contemporary skeletal collections from Crete (Greece), Limassol (Cyprus), Coimbra (Portugal) and Salvador (Brazil) were assessed by the authors of this paper for non-metric cranial traits. Out of 711 skulls, only three cases of parietal division were found and all three originated from the Cypriot collection. These three cases were anatomically analyzed, showing that all three cases were adult females and showed unilateral expression of the trait. Two skulls showed superoinferior division, and the third case showed anteroposterior division. Numerous other cranial non-metric traits were found in these three skulls. Based on the cemetery archives, there seems to be no genetic link between the individuals bearing this trait. Further genetic analysis is suggested in order to verify this conclusion.

Considering the Influence of Nonadaptive Evolution on Primate Color Vision.

Color vision in primates is variable across species, and it represents a rare trait in which the genetic mechanisms underlying phenotypic variation are fairly well-understood. Research on primate color vision has largely focused on adaptive explanations for observed variation, but it remains unclear why some species have trichromatic or polymorphic color vision while others are red-green color blind. Lemurs, in particular, are highly variable. While some species are polymorphic, many closely-related species are strictly dichromatic. We provide the first characterization of color vision in a wild population of red-bellied lemurs (Eulemur rubriventer, Ranomafana National Park, Madagascar) with a sample size (87 individuals; NX chromosomes = 134) large enough to detect even rare variants (0.95 probability of detection at ≥ 3% frequency). By sequencing exon 5 of the X-linked opsin gene we identified opsin spectral sensitivity based on known diagnostic sites and found this population to be dichromatic and monomorphic for a long wavelength allele. Apparent fixation of this long allele is in contrast to previously published accounts of Eulemur species, which exhibit either polymorphic color vision or only the medium wavelength opsin. This unexpected result may represent loss of color vision variation, which could occur through selective processes and/or genetic drift (e.g., genetic bottleneck). To indirectly assess the latter scenario, we genotyped 55 adult red-bellied lemurs at seven variable microsatellite loci and used heterozygosity excess and M-ratio tests to assess if this population may have experienced a recent genetic bottleneck. Results of heterozygosity excess but not M-ratio tests suggest a bottleneck might have occurred in this red-bellied lemur population. Therefore, while selection may also play a role, the unique color vision observed in this population might have been influenced by a recent genetic bottleneck. These results emphasize the need to consider adaptive and nonadaptive mechanisms of color vision evolution in primates.

유교유산을 활용한 관광문화복지 구현에 대한 연구 - 유교건물을 중심으로 -

본 연구는 유교유산을 활용한 관광문화복지 구현에 대한 연구를 하고자 한다. 연구대상은 2014년 6월13일부터 11월7일까지 영월군의 향교, 서원, 누정을 대상으로 실태 및 면접조사를 실시하였다. 자료분석은 척도문항을 중심으로 현장조사, 건물소유자와 관리자의 심층면접을 실시하였으며, 과학적 탐구과정을 거쳐서 판단하고 분석하였다. 분석결과는 첫째, 역사적 배경은 문화재적 가치로 매우 귀중한 지역의 관광 및 문화복지 자산인 것으로 파악되었다. 둘째, 향교와 서원은 전통유교문화형식을 보이고 있으나, 누정건축에서는 보기 드문 특색을 나타내고 있어 특화된 사회적 관광자원화가 요구된다. 셋째, 유교유산에 대한 관광문화복지 자원화가 아직은 미흡한 실정으로 파악 되므로 이에 대한 마케팅강화와 프로그램의 개발과 운용이 절실하다. 본 연구의 시사점은 유교문화의 계승과 현대적 재해석이 필요하며, 이를 토대로 유교문화와 현대문화를 아우르는 디지털관광으로의 발상전환 그리고 지역과 상생하는 관광문화복지 정책의 연구가 이루어져야 할 것으로 사료된다. The present study investigates the realization of tourism culture welfare by using Confucian heritage. From June 13 to November 7, 2014, site surveys and interviews were conducted for hyanggo (hyanggo: Confucian temple and school to teach students in Joseon Dynasty period), seowon (seowon: a memorial hall for Confucianist services to honor distinguished scholars and statesmen) and nujung (nujung: outdoor pavilion or gazebo) located in Youngwol -gun. Questionnaire pertaining to site survey and in-depth interviews for the building owners and managers was used to collect necessary data and scientific investigation was performed for analysis. As a result, the historical background was found to be culturally valuable asset for both region's tourism and culture welfare. Secondly, hyanggyo and seowon were found to exhibit traditional Confucius cultural form, while nujung exhibited a rare architectural trait. Hence it seems necessary to develop a different social tourism resource specialized for nujung. Thirdly, the rendering of Confucius heritages to tourism culture welfare resources thus far seems to be insufficient; hence, development and operation of marketing programs will be necessary. The implications of the present study require succession and modern reinterpretation of Confucian heritages for further development into digital tourism that will encompass Confucian culture and today's culture. Furthermore, studies of the tourism culture welfare policies that will promote the co-existence with the region will be needed.

Frequencies of Rare Incisor Variations Reflect Factors Influencing Precontact Population Relationships in Mexico and the American Southwest

AbstractMexican prehistory is characterized by migration and population isolation in its earliest phase, followed by later inter‐population cultural interactions, such as politics and trade. While shared, common morphological variants are often informative about recent population events, rare trait variants have not been widely investigated to see whether they might be informative about earlier events. Here, we consider populations that show several rare variants at frequencies high enough to warrant such an investigation. Examining past population structure can help us understand population interactions across different periods of time, levels of migration, and population isolation/drift. Multiple‐origin populations may have more variation, including more and higher rates of rare traits. We examined maxillary lateral incisors in 1117 dentitions from 76 samples of Preclassic/Classic and Postclassic pre‐European contact Mexico and the American Southwest for the prevalence of rare lateral incisor variants. Variants observed included barrel, congenital absence, interruption groove, mesial marginal bending, peg, reduced, supernumerary, and talon teeth. The most common variant overall is interruption groove. Central Mexico, Huasteca, and the Lowland Yucatan region samples present the highest overall number of incisor variants. Higher frequencies of single unusual traits are commonly found in samples from smaller populations, while samples from larger population centres show a greater range of these rare variants. We investigated to see whether the pattern of rare incisor variant frequencies reflected early or later population history by comparing similarity/distance matrices and factor model matrices using Mantel tests and Generalized Procrustes analysis. Results show a weak relationship with the Postclassic period and shared migration/language and trade interaction models. We suggest that later cultural interactions have acted to mask earlier population history. Research on serial founder effects should be approached multiregionally and across time, to avoid missing inter‐region biological relationships. Copyright © 2015 John Wiley & Sons, Ltd.

Isolation of oxalotrophic bacteria associated with Varroa destructor mites.

Bacteria associated with varroa mites were cultivated and genotyped by 16S RNA. Under our experimental conditions, the cultivable bacteria were few in number, and most of them proved to be fastidious to grow. Cultivation with seven different media under O2 /CO2 conditions and selection for colony morphology yielded a panel of species belonging to 13 different genera grouped in two different phyla, proteobacteria and actinobacteria. This study identified one species of actinobacteria that is a known commensal of the honey bee. Some isolates are oxalotrophic, a finding that may carry ramifications into the use of oxalic acid to control the number of phoretic mites in the managed colonies of honey bees. Oxalic acid, legally or brevi manu, is widely used to control phoretic Varroa destructor mites, a major drive of current honey bees' colony losses. Unsubstantiated by sanctioned research are rumours that in certain instances oxalic acid is losing efficacy, forcing beekeepers to increase the frequency of treatments. This investigation fathoms the hypothesis that V. destructor associates with bacteria capable of degrading oxalic acid. The data show that indeed oxalotrophy, a rare trait among bacteria, is common in bacteria that we isolated from V. destructor mites. This finding may have ramifications in the use of oxalic acid as a control agent.

Metal hyperaccumulation in Brassicaceae mediates defense against herbivores in the field and improves growth

AbstractSeveral Brassicaceae species are able to hyperaccumulate extraordinarily high levels of heavy metals in their aboveground tissues. This rare and complex trait named metal hyperaccumulation may offer effective protection against antagonists. Several laboratory studies provide evidence that metal hyperaccumulation acts as an elemental defense. Here, we investigated whether this elemental defense can be confirmed in the field and whether plant growth is affected when plants can hyperaccumulate metals from the soil. Plants of Arabidopsis halleri (L.) O'Kane & Al‐Shehbaz, which can hyperaccumulate cadmium (Cd) and zinc (Zn), were cultivated in pots in unamended (control) or metal‐amended soil (test) for 2 months. The pots containing the plants were then transferred to a common garden. Leaf‐damaging insect visitors were monitored over a period of 3 months. Plant size and shoot mass were measured directly before and at the end of the field exposure. Furthermore, before and at the end of the field exposure we determined leaf concentrations of Cd and Zn, as well as glucosinolates, which are characteristic secondary metabolites of the Brassicaceae that are known to act potentially as organic defense compounds. Growth of the test plants on metal‐amended soil led to a significant increase in leaf Cd and Zn concentrations when compared to control plants on unamended soil. After two initial months of growth under standardized greenhouse conditions, plants grown on different soils did not differ in size or biomass. In contrast, by the end of the 3‐month field exposure, test plants were larger than control plants. During field exposure, control plants were visited by more herbivores, suggesting that plants growing on metal‐amended soil were well defended against herbivores. Total glucosinolate concentrations were significantly higher in test compared to control plants only after the initial growth period under standardized conditions, but not by the end of the field exposure, pointing to joint effects of defenses particularly in young plants. Our results demonstrate that metal hyperaccumulation affords an effective elemental defense and enables increased growth under field conditions.

Identification of genes essential for pellicle formation in Acinetobacter baumannii.

BackgroundAcinetobacter baumannii is an opportunistic pathogen, which has the ability to persist in the clinical environment, causing acute and chronic infections. A possible mechanism contributing to survival of A. baumannii is its ability to form a biofilm-like structure at the air/liquid interface, known as a pellicle. This study aimed to identify and characterise the molecular mechanisms required for pellicle formation in A. baumannii and to assess a broad range of clinical A. baumannii strains for their ability to form these multicellular structures.ResultsRandom transposon mutagenesis was undertaken on a previously identified hyper-motile variant of A. baumannii ATCC 17978 designated 17978hm. In total three genes critical for pellicle formation were identified; cpdA, a phosphodiesterase required for degradation of cyclic adenosine monophosphate (cAMP), and A1S_0112 and A1S_0115 which are involved in the production of a secondary metabolite. While motility of the A1S_0112::Tn and A1S_0115::Tn mutant strains was abolished, the cpdA::Tn mutant strain displayed a minor alteration in its motility pattern. Determination of cAMP levels in the cpdA::Tn strain revealed a ~24-fold increase in cellular cAMP, confirming the role CpdA plays in catabolising this secondary messenger molecule. Interestingly, transcriptional analysis of the cpdA::Tn strain showed significant down-regulation of the operon harboring the A1S_0112 and A1S_0115 genes, revealing a link between these three genes and pellicle formation. Examination of our collection of 54 clinical A. baumannii strains revealed that eight formed a measurable pellicle; all of these strains were motile.ConclusionsThis study shows that pellicle formation is a rare trait in A. baumannii and that a limited number of genes are essential for the expression of this phenotype. Additionally, an association between pellicle formation and motility was identified. The level of the signalling molecule cAMP was found to be controlled, in part, by the cpdA gene product, in addition to playing a critical role in pellicle formation, cellular hydrophobicity and motility. Furthermore, cAMP was identified as a novel regulator of the operon A1S_0112-0118.Electronic supplementary materialThe online version of this article (doi:10.1186/s12866-015-0440-6) contains supplementary material, which is available to authorized users.

Ecological, evolutionary and social constraints on reproductive effort: are hoary marmots really biennial breeders?

Biennial breeding is a rare life-history trait observed in animal species living in harsh, unproductive environments. This reproductive pattern is thought to occur in 10 of 14 species in the genus Marmota, making marmots useful model organisms for studying its ecological and evolutionary implications. Biennial breeding in marmots has been described as an obligate pattern which evolved as a mechanism to mitigate the energetic costs of reproduction (Evolved Constraint hypothesis). However, recent anecdotal evidence suggests that it is a facultative pattern controlled by annual variation in climate and food availability (Environmental Constraint hypothesis). Finally, in social animals like marmots, biennial breeding could result from reproductive competition between females within social groups (Social Constraint hypothesis). We evaluated these three hypotheses using mark-recapture data from an 8-year study of hoary marmot (Marmota caligata) population dynamics in the Yukon. Annual variation in breeding probability was modeled using multi-state mark-recapture models, while other reproductive life-history traits were modeled with generalized linear mixed models. Hoary marmots were neither obligate nor facultative biennial breeders, and breeding probability was insensitive to evolved, environmental, or social factors. However, newly mature females were significantly less likely to breed than older individuals. Annual breeding did not result in increased mortality. Female survival and, to a lesser extent, average fecundity were correlated with winter climate, as indexed by the Pacific Decadal Oscillation. Hoary marmots are less conservative breeders than previously believed, and the evidence for biennial breeding throughout Marmota, and in other arctic/alpine/antarctic animals, should be re-examined. Prediction of future population dynamics requires an accurate understanding of life history strategies, and of how life history traits allow animals to cope with changes in weather and other demographic influences.

A sphere-forming scarab beetle (Ceratocanthinae: Hybosoridae) in Dominican amber

The ability of beetles to form defensive spheres is a rare trait and confined to representatives in the families Clambidae, Leiodidae and Hybosoridae. However, the most compact spheres are formed by members of the Neotropical genus Ceratocanthus (Ceratocanthinae: Hybosoridae). A representative in Dominican amber described as Ceratocanthus emarginatus sp.n. differs from all known members of the genus by its unique notched clypeus. Additional specimens of at least two other species suggest that these sphere-forming beetles were fairly diverse in the Dominican amber forest.http://www.zoobank.org/urn:lsid:zoobank.org:pub:4329D0DA-57BD-4CEA-9464-ABD5D1577FC9

Differential FoxP2 and FoxP1 expression in a vocal learning nucleus of the developing budgerigar.

The forkhead domain FOXP2 and FOXP1 transcription factors are implicated in several cognitive disorders with language deficits, notably autism, and thus play a central role in learned vocal motor behavior in humans. Although a similar role for FoxP2 and FoxP1 is proposed for other vertebrate species, including songbirds, the neurodevelopmental expression of these genes are unknown in a species with lifelong vocal learning abilities. Like humans, budgerigars (Melopsittacus undulatus) learn new vocalizations throughout their entire lifetime. Like songbirds, budgerigars have distinct brain nuclei for vocal learning, which include the magnocellular nucleus of the medial striatum (MMSt), a basal ganglia region that is considered developmentally and functionally analogous to Area X in songbirds. Here, we used in situ hybridization and immunohistochemistry to investigate FoxP2 and FoxP1 expression in the MMSt of juvenile and adult budgerigars. We found FoxP2 mRNA and protein expression levels in the MMSt that were lower than the surrounding striatum throughout development and adulthood. In contrast, FoxP1 mRNA and protein had an elevated MMSt/striatum expression ratio as birds matured, regardless of their sex. These results show that life-long vocal plasticity in budgerigars is associated with persistent low-level FoxP2 expression in the budgerigar MMSt, and suggests the possibility that FoxP1 plays an organizational role in the neurodevelopment of vocal motor circuitry. Thus, developmental regulation of the FoxP2 and FoxP1 genes in the basal ganglia appears essential for vocal mimicry in a range of species that possess this relatively rare trait.

Trehalose Is a Versatile and Long-Lived Chaperone for Desiccation Tolerance

Diverse organisms across taxa are desiccation tolerant, capable of surviving extreme water loss. Remarkably, desiccation tolerant organisms can survive years without water. However, the molecular mechanisms underlying this rare trait are poorly understood. Here, using Saccharomyces cerevisiae, we show that intracellular trehalose is essential for survival to long-term desiccation. The time frame for maintaining long-term desiccation tolerance consists of a balance of trehalose stockpiled prior to desiccation and trehalose degradation by trehalases in desiccated cells. The activity of trehalases in desiccated cell reveals the stunning ability of cells to retain enzymatic activity while desiccated. Interestingly, the protein chaperone Hsp104 compensates for loss of trehalose during short-term, but not long-term, desiccation. We show that desiccation induces protein misfolding/aggregation of cytoplasmic and membrane proteins using luciferase and prion reporters. We demonstrate that trehalose, but not Hsp104, mitigates the aggregation of both cytoplasmic and membrane prions. We propose that desiccated cells initially accumulate both protein and chemical chaperones, like Hsp104 and trehalose, respectively. As desiccation extends, the activities of the protein chaperones are lost because of their complexity and requirement for energy, leaving trehalose as the major protector against the aggregation of cytoplasmic and membrane proteins. Our results suggest that trehalose is both a more stable and more versatile protectant than protein chaperones, explaining its important role in desiccation tolerance and emphasizing the translational potential of small chemical chaperones as stress effectors.

Catridecacog: a breakthrough in the treatment of congenital factor XIII A-subunit deficiency?

Circulating factor XIII (FXIII) consists of two active (A) and two carrier (B) subunits in tetrameric form. Congenital FXIII deficiency is a rare autosomal-recessive trait that mostly results from an FXIII A-subunit deficiency. Classic coagulation assays, such as prothrombin time or activated partial thromboplastin time, are not sensitive to FXIII; therefore, specific FXIII assays are necessary to detect the deficiency. The clinical picture of congenital FXIII deficiency comprises abortions, umbilical cord bleeding, increased surgical bleeding, intracerebral hemorrhage (which can, unfortunately, be the very first sign of severe FXIII deficiency), menorrhagia, and wound-healing disorders. Given the risk of intracranial hemorrhage, continued prophylaxis is to be recommended in severe deficiency, even in the actual absence of bleeding symptoms. Functional FXIII half-life decreases in consumptive processes (eg, surgery), explaining why increased dosing is needed in such situations. A recombinant FXIII (rFXIII) subunit-A molecule, which is expressed in Saccharomyces cerevisiae, has been evaluated for replacement therapy in congenital FXIII deficiency. The bleeding frequency under continued rFXIII prophylaxis during a year-long treatment period was significantly lower compared to on-demand treatment. Importantly, no severe spontaneous bleedings occurred, and bleeding requiring additional intervention only occurred after relevant trauma. Treatment with rFXIII proved to be safe: antibodies against rFXIII detected in four patients were not considered clinically relevant. No allergic reactions were observed. These data show that rFXIII can be used safely and effectively for continued prophylaxis in congenital FXIII deficiency; it is conceivable that this also holds true for treatment of acute bleeding, but clinical proof of this is pending.

Further evidence for phenotypic signatures of hybridization in descendant baboon populations

Hybridization may have played a substantial role in shaping the diversity of our evolving lineage. Although recent genomic evidence has shown that hybridization occurred between anatomically modern humans (AMHS) and Neanderthals, it remains difficult to pin down precisely where and when this gene flow took place. Investigations of the hybrid phenotype in primates and other mammals are providing models for identifying signatures of hybridization in the fossil record. However, our understanding of intra- and inter-taxon variation in hybrids is still limited. Moreover, there is little evidence from these studies that is pertinent to the question of how long hybrid skeletal traits persist in descendants, and therefore it is not clear whether observed hybrid phenotypes are evidence of recent (e.g., F1) or much earlier hybridization events. Here, we present an analysis updating a previous study of cranial variation in pedigreed olive and yellow baboons and their hybrids. Results suggest that traits previously associated with hybrids in baboons and other mammalian species are also present in this expanded data set; many of these traits are highly heritable, confirming a genetic basis for their variation in this mixed population. While F1 animals – and especially F1 males – still have the highest number of dental anomalies, these and other atypical traits persist into later hybrid generations (such as F2 and B1). Moreover, non-F1 recombinants also show extremely rare trait variations, including reduced canines and rotated teeth. However, these results must be considered in light of the possibility that some founding individuals may have themselves been unrecognized hybrids. Despite this, the data are compelling, and indicate once again that further controlled research remains to be done on primates and other mammals in order to better understand variation in the hybrid phenotype.

Cisplatin-Based Chemotherapy and the Risk of Solid Tumors in Patients With Testicular Nonseminoma: Still a Matter of Debate

TO THE EDITOR: Fung et al compared the risks of secondary malignancies among patients treated with chemotherapy or surgery alone for testicular nonseminoma. Utilizing the population-based SEER cohort, Fung et al found that chemotherapy-treated men had a 40% increased risk of developing secondary malignancies after initial diagnosis. Although the study is without doubt an important assessment given the rising incidence of testicular cancer in the last decades, several limitations should be raised, which may weaken the clinical applicability of their findings in the contemporary era. First, since the study span covered diagnoses from 1980 to 2008, Fung et al could not account for the variable chemotherapy regimens that were introduced over time. Patients diagnosed and treated in more recent years with newer and less toxic chemotherapy regimens might be at considerably lower risk of secondary malignancies compared to historical chemotherapy regimens used 30 years ago. Second, the lack of consideration for disease stage in the calculation of standardized incidence ratios for secondary malignancies further augments the heterogeneity of the studied population. Of note, 34% of patients treated with chemotherapy harbored metastatic disease versus 1.7% in the surgery group. Given the prevalence of metastatic patients in the chemotherapy group, Fung et al are unable to rule out the confounding effect of biologic mechanisms. Specifically, inheritance of both rare genetic variants and polygenic trait predisposing to the development of advanced disease, may ultimately increase the risks of a new onset of secondary malignancies. Third, the number of cycles and dosage received is equally unknown. For example, metastatic patients are likely to be exposed to significantly higher cumulative doses of chemotherapeutic agents compared to individuals with stage I testicular nonseminoma. Thus, the current study is not able to provide insight into the dose-response relationship between chemotherapy and the subsequent risk of solid malignancies. In conclusion, the evaluation of the potential role of chemotherapy on the development of secondary malignancies relative to surgery in patients with testicular nonseminoma is highly relevant. However several other important aspects—improvements in chemotherapy regimens used in contemporary years, a better defined population according to disease stage, better knowledge of dosage and cycles used—need to be factored in the assessment of this association to avoid over-attributing the long-term adverse effects of chemotherapy.

Muscle Disease

On the basis of strong research evidence, Duchenne muscular dystrophy (DMD), the most common severe childhood form of muscular dystrophy, is an X-linked recessive disorder caused by out-of-frame mutations of the dystrophin gene. Thus, it is classified asa dystrophinopathy. The disease onset is before age 5 years. Patients with DMD present with progressive symmetrical limb-girdle muscle weakness and become wheelchair dependent after age 12 years. (2)(3). On the basis of some research evidence,cardiomyopathy and congestive heart failure are usually seen in the late teens in patients with DMD. Progressive scoliosis and respiratory in sufficiency often develop once wheelchair dependency occurs. Respiratory failure and cardiomyopathy are common causes of death, and few survive beyond the third decade of life. (2)(3)(4)(5)(6)(7). On the basis of some research evidence, prednisone at 0.75 mg/kg daily (maximum dose, 40 mg/d) or deflazacort at 0.9 mg/kg daily (maximum dose, 39 mg/d), a derivative of prednisolone (not available in the United States), as a single morning dose is recommended for DMD patients older than 5 years, which may prolong independent walking from a few months to 2 years. (2)(3)(16)(17). Based on some research evidence, treatment with angiotensin-converting enzyme inhibitors, b-blockers, and diuretics has been reported to be beneficial in DMD patients with cardiac abnormalities. (2)(3)(5)(18). Based on expert opinion, children with muscle weakness and increased serum creatine kinase levels may be associated with either genetic or acquired muscle disorders (Tables 1 and 3). (14)(15)

Refining rare weed trait syndromes along arable intensification gradients.

QuestionHow does the conservation (rarity) value of arable weed communities differ along intensification gradients? Which functional traits best distinguish the weed communities of more and less extensively managed fields? Can the same traits predict the rarity of individual weed species?LocationHungary.MethodsUsing relevé data from 60 cereal and 70 stubble fields, together with weed trait data, we characterized community responses to arable intensification using functional trait analyses based on trait‐convergence and trait‐divergence assembly patterns. We also examined how well the broad‐scale rarity status of species predicts their occurrence along intensification gradients, and how it maps onto our functional classifications describing intensification responses.ResultsThe response of weeds to intensification in cereal fields was best described by a functional classification based on species' flowering duration, maximum height and seed weight: weeds of extensively managed fields have short flowering seasons (2–5 mo) and particularly large or small seeds. The highest proportions of rare species also happen to be found in these groups. The rarest weeds among these species tend to be late‐winter and early‐summer annuals, while the rare species of stubble fields tend to be broad‐leaved with low nitrogen requirements, small seeds and short height. Stubble fields showed a decline in weed cover with increasing application of fertilizer and distance from the field edge, but we could detect no strong associations of management factors with trait composition, perhaps because the intensification gradient across these fields was shorter.ConclusionsMany rare Hungarian weeds are associated with traditional extensive farming practices. They are particularly characterized by short, midsummer flowering periods and by preference for low nitrogen levels, but a range of trait syndromes must be considered to understand their ecology and conservation. Analyses based on trait‐divergence patterns, rather than trait‐convergence patterns, provide better insights into the functional composition of weed communities, emphasizing the importance of disruptive filters in weed community assembly and the need for improved methods to detect such effects.

Paramolar tubercle (Parastyle) in primary molars of Davangere (India) children: A retrospective study

Aim: To estimate the prevalence of paramolar tubercle (extra cusp) in primary molars of Indian children. Materials and Methods: A survey was conducted in children aged 2-8 years reporting during the period from 2006 to 2008. For recording paramolar tubercle, the definition given by Scott and Turner was employed. Subjects found with paramolar structure were further subjected to radiographic examination and impressions were made for further analysis of the paramolar tubercle. Results: Paramolar tubercle was noticed in eight patients (five boys and three girls). Among the eight patients, one patient had bilateral presence of paramolar tubercle. In seven patients, it was found on the right side and in two patients, it was found on the left side. We found type I in one case, type II in one case, type III in four cases, type IV in two cases and type V in one patient. Based on the different morphological patterns of paramolar tubercle observed during this study, we propose a new diagnostic classification system for better grading and understanding this rare dental trait, particularly for primary molars. Conclusion: As the frequency of paramolar tubercle is very rare, more studies involving different races have to be performed, rather involving individual cases, to show its unilateral/bilateral presence, sexual predominance and also to analyze the size and pattern of the paramolar tubercle.

Food rewards modulate the activity of song neurons in Bengalese finches

Vocal learning, a critical component of speech acquisition, is a rare trait in animals. Songbirds are a well-established animal model in vocal learning research; male birds acquire novel vocal patterns and have a well-developed 'song system' in the brain. Although this system is unique to songbirds, anatomical and physiological studies have reported similarities between the song system and the thalamo-cortico-basal ganglia circuit that is conserved among reptiles, birds, and mammals. Here, we focused on the similarity of the neural response between these two systems while animals were engaging in operant tasks. Neurons in the basal ganglia of vertebrates are activated in response to food rewards and reward predictions in behavioral tasks. A striatal nucleus in the avian song system, Area X, is necessary for vocal learning and is considered specialized for singing. We found that the spiking activity of singing-related Area X neurons was modulated by food rewards and reward signals in an operant task. As previous studies showed that Area X is not critical for general cognitive tasks, the role of Area X in general learning might be limited and vestigial. However, our results provide a new viewpoint to investigate the independence of the vocal learning system from neural systems involved in other cognitive tasks.