bluuebunny/crossref_metadata_2025 huggingface dataset:
Insights on the mechanisms of Ca2+ regulation of connexin26 hemichannels revealed by human pathogenic mutations (D50N/Y)
Authors: Lopez William , Gonzalez Jorge , Liu Yu , Harris Andrew L. , Contreras Jorge E.
Published: June 2013

Because of the large size and modest selectivity of the connexin hemichannel aqueous pore, hemichannel opening must be highly regulated to maintain cell viability. At normal resting potentials, this regulation is achieved predominantly by the physiological extracellular Ca2+ concentration, which drastically reduces hemichannel activity. Here, we characterize the Ca2+ regulation of channels formed by wild-type human connexin26 (hCx26) and its human mutations, D50N/Y, that cause aberrant hemichannel opening and result in deafness and skin disorders. We found that in hCx26 wild-type channels, deactivation kinetics are accelerated as a function of Ca2+ concentration, indicating that Ca2+ facilitates transition to, and stabilizes, the closed state of the hemichannels. The D50N/Y mutant hemichannels show lower apparent affinities for Ca2+-induced closing than wild-type channels and have more rapid deactivation kinetics, which are Ca2+ insensitive. These results suggest that D50 plays a role in (a) stabilizing the open state in the absence of Ca2+, and (b) facilitating closing and stabilization of the closed state in the presence of Ca2+. To explore the role of a negatively charged residue at position 50 in regulation by Ca2+, this position was substituted with a cysteine residue, which was then modified with a negatively charged methanethiosulfonate reagent, sodium (2-sulfanoethyl) methanethiosulfonate (MTSES)−. D50C mutant hemichannels display properties similar to those of D50N/Y mutants. Recovery of the negative charge with chemical modification by MTSES− restores the wild-type Ca2+ regulation of the channels. These results confirm the essential role of a negative charge at position 50 for Ca2+ regulation. Additionally, charge-swapping mutagenesis studies suggest involvement of a salt bridge interaction between D50 and K61 in the adjacent connexin subunit in stabilizing the open state in low extracellular Ca2+. Mutant cycle analysis supports a Ca2+-sensitive interaction between these two residues in the open state of the channel. We propose that disruption of this interaction by extracellular Ca2+ destabilizes the open state and facilitates hemichannel closing. Our data provide a mechanistic understanding of how mutations at position 50 that cause human diseases are linked to dysfunction of hemichannel gating by external Ca2+.
The mechanoelectrical response of the cytoplasmic membrane of Vibrio cholerae
Authors: Rowe Ian , Elahi Merina , Huq Anwar , Sukharev Sergei
Published: June 2013

Persistence of Vibrio cholerae in waters of fluctuating salinity relies on the capacity of this facultative enteric pathogen to adapt to varying osmotic conditions. In an event of osmotic downshift, osmolytes accumulated inside the bacterium can be quickly released through tension-activated channels. With the newly established procedure of giant spheroplast preparation from V. cholerae, we performed the first patch-clamp characterization of its cytoplasmic membrane and compared tension-activated currents with those in Esherichia coli. Saturating pressure ramps revealed two waves of activation belonging to the ∼1-nS mechanosensitive channel of small conductance (MscS)-like channels and ∼3-nS mechanosensitive channel of large conductance (MscL)-like channels, with a pressure midpoint ratio p0.5MscS/p0.5MscL of 0.48. We found that MscL-like channels in V. cholerae present at a density three times higher than in E. coli, and yet, these vibrios were less tolerant to large osmotic downshocks. The Vibrio MscS-like channels exhibit characteristic inward rectification and subconductive states at depolarizing voltages; they also adapt and inactivate at subsaturating tensions and recover within 2 s upon tension release, just like E. coli MscS. Trehalose, a compatible internal osmolyte accumulated under hypertonic conditions, significantly shifts activation curves of both MscL- and MscS-like channels toward higher tensions, yet does not freely partition into the channel pore. Direct electrophysiology of V. cholerae offers new avenues for the in situ analysis of membrane components critical for osmotic survival and electrogenic transport in this pathogen.
Impact of increasing deployment of artificial floating objects on the spatial distribution of social fish species
Authors: Sempo Grégory , Dagorn Laurent , Robert Marianne , Deneubourg Jean‐Louis
Published: June 2013

Approximately 300 pelagic fish species naturally aggregate around floating objects (FOBs) at the surface of the oceans. Currently, more than 50% of the world catch of tropical tuna comes from the industrial tuna fisheries around driftingFOBs. Greater understanding of the complex decision‐making processes leading to this aggregation pattern and the impact of the massive release of artificialFOBs by fishermen on the spatial distribution and management of tuna is needed.

We analyse how the interplay between social (relationships between individuals) and non‐social (responses to the environment) behaviours may affect the spatial distribution of a population in a multi‐FOBenvironment. Taking the example of tropical tunas associating withFOBs and using differential equations and stochastic simulations, we examine how, when increasing the number ofFOBs, fish aggregation dynamics and the distribution of the population among patches are affected by the population size, level of sociality and the natural retentive and/or attractive forces ofFOBs on individual tuna.

Our model predicts that, depending on the species' level of sociality, fish will be scattered amongFOBs or aggregated around a singleFOBbased on the number ofFOBs deployed in a homogeneous oceanic region.

For social species, we demonstrated that the total fish catch is reduced with increasingFOBs number. Indeed, for each size of population, there are a number ofFOBs minimizing the total population of fish associated withFOBs and another number ofFOBs maximizing the total population of associated fish.

Synthesis and applications. In terms of fisheries management, the total catch volume is directly linked to the total number of floating objects (FOBs) for non‐social species, and any limit on the number of sets would then result in a limit on the total catch. For social species (e.g. tuna), however, increasing the number ofFOBs does not necessarily lead to an increase in the total catch, which is a non‐intuitive result. Indeed, our model shows that, for specific values of the parameters, deploying a greater number ofFOBs in the water (all other parameters being constant) does not necessarily help fishermen to catch more tuna, but does increase the level of fishing effort and bycatch.
Protocols for dry DNA storage and shipment at room temperature
Authors: Ivanova Natalia V. , Kuzmina Masha L.
Published: June 2013

The globalization of DNA barcoding will require core analytical facilities to develop cost‐effective, efficient protocols for the shipment and archival storage of DNA extracts and PCR products. We evaluated three dry‐state DNA stabilization systems: commercial Biomatrica® DNAstable® plates, home‐made trehalose and polyvinyl alcohol (PVA) plates on 96‐well panels of insect DNA stored at 56 °C and at room temperature. Controls included unprotected samples that were stored dry at room temperature and at 56 °C, and diluted samples held at 4 °C and at −20 °C. PCR and selective sequencing were performed over a 4‐year interval to test the condition of DNA extracts. Biomatrica® provided better protection of DNA at 56 °C and at room temperature than trehalose and PVA, especially for diluted samples. PVA was the second best protectant after Biomatrica® at room temperature, whereas trehalose was the second best protectant at 56 °C. In spite of lower PCR success, the DNA stored at −20 °C yielded longer sequence reads and stronger signal, indicating that temperature is a crucial factor for DNA quality which has to be considered especially for long‐term storage. Although it is premature to advocate a transition to DNA storage at room temperature, dry storage provides an additional layer of security for frozen samples, protecting them from degradation in the event of freezer failure. All three forms of DNA preservation enable shipment of dry DNA and PCR products between barcoding facilities.
Antioxidant profile in patients with complex regional pain syndrome type I
Authors: Baykal Tuba , Seferoglu Buminhan , Karsan Orhan , Kiziltunc Ahmet , Senel Kazim
Published: June 2013

Objective

Complex regional pain syndrome (CRPS) type I is one of the most important problems with regard to physical medicine and rehabilitation. CRPS may cause not only higher therapeutic costs but also greater work time loss. The mechanism and pathogenesis of CRPS still remains unknown. Some findings indicating oxidative stress have been reported. This study was carried out to determine the role of oxidative stress in patients with CRPS.

Materials and methods

Twenty patients (13 women and seven men) with CRPS and 20 age‐ and sex‐matched healthy controls were enrolled in this study. Complex regional pain syndrome was diagnosed according to the modified International Association for the Study of Pain (IASP) criteria. We evaluated demographic, clinical and laboratory characteristics of the patients. Antioxidant enzymatic activities consisting of serum superoxide dismutase (SOD), glutathion peroxidase (GPX) and glutathione S‐transferase (GST) activities were measured using appropriate methods and compared with healthy controls.

Results

The mean age of the patients was 39.5 years and the mean duration of symptoms was 5.5 months. Complex regional pain syndrome devoleped after a traumatic event in 90% of patients. In 10% of patients there were no traumatic events. SOD, GPX and GST levels were significantly higher in patients with CRPS than healthy controls (P = 0.012, P = 0.036 and P = 0.016, respectively).

Conclusion

Our findings suggest a possible role of oxidative stress in the pathogenesis of CRPS.
Seed addition via epizoochorous dispersal in restoration: an experimental approach mimicking the colonization of bare soil patches
Authors: Freund Linda , Eichberg Carsten , Retta Iris , Schwabe Angelika
Published: June 2013

Questions

Does epizoochorous dispersal via sheep lead to the establishment of populations of sandy grassland species on newly created, managed restoration sites on sandy bare soil? Do epizoochorously‐induced spatial patterns persist during vegetation development? Does sandy grassland develop, which is rich in epizoochorously‐dispersed target species?

Location

Upper Rhine Valley, Germany.

Methods

A 6‐yr experiment on epizoochorous dispersal by sheep was conducted on three newly created deep sand deposition sites mimicking restoration areas with reduced nutrient availability. Establishment success and persistence of ten epizoochorously‐dispersed species were assessed and spatial patterns were analysed using SADIE (Spatial Analysis by Distance Indices). Vegetation development of the experimental areas was related to a nearby nature reserve (relevés, target species ratios). In addition, seed rain and early‐successional soil seed bank were sampled.

Results

All but one species dispersed by sheep became established and persisted during the 6‐yr study. After establishment, most perennials did not change or increased in abundance over time, whereas annuals showed various population dynamics. Spatial patterns were aggregated for most study species. Similarity of spatial patterns between consecutive years varied by species, site and year, and was stronger in perennial than in annual species. Patterns of seed dispersal and establishment were positively associated with each other (a subset of three species was tested). Within 6 yrs, the proportion, but not the cover, of target species in the experimental areas reached a level similar to that of a nearby nature reserve; however, many species characteristic of the nature reserve were absent. The species compositions of both seed bank and seed rain were dominated by non‐target species.

Conclusions

Sheep flocks may assist in colonization of grassland species on newly created bare soil areas via epizoochory. The incorporation of livestock into restoration projects might facilitate the regeneration and preservation of threatened plant populations. Livestock might be most successful in promoting biodiversity if they are moved from communities with target species to restoration areas.
Effect of Rosiglitazone on Liver Structure and Function in Genetically Diabetic Akita Mice
Authors: Hemmeryckx Bianca , Gaekens Marijke , Gallacher David J. , Lu Hua Rong , Lijnen Henri Roger
Published: June 2013

Genetically diabetic Akita mice, kept on a high‐fat and high‐cholesterol diet, and treated with the peroxisome proliferator‐activated receptor‐γ agonist rosiglitazone (10 mg/kg per day during 4 months), displayed rosiglitazone‐induced side effects, similar to those observed in patients, including weight and fat gain and early signs of hypertrophic cardiomyopathy. As several cases of hepatotoxicity were reported in patients receiving rosiglitazone treatment, this study evaluated whether rosiglitazone also induced hepatotoxicity in these diabetic animals. Liver structure and function was analysed in wild‐type and rosiglitazone‐treated and untreated Akita mice, kept for 4 months on the high‐fat and high‐cholesterol diet. Decreased circulating levels of the liver enzymes aspartate and alanine aminotransferase and increased levels of alkaline phosphatases were observed upon rosiglitazone treatment, whereas liver weight was markedly increased. Rosiglitazone administration was associated with liver steatosis, as demonstrated by triglyceride accumulation. However, gene expression of steatosis markers in liver tissue was not markedly affected by rosiglitazone treatment, while expression of fatty acid transport protein was reduced by rosiglitazone treatment, suggesting an impairment of the fatty acid β‐oxidation pathway. mRNA expression of pro‐ and anti‐oxidant enzymes and liver 3‐nitrotyrosine content was not affected. Furthermore, gene and protein expression of macrophage markers and of cell adhesion molecules did not indicate progression to steatohepatitis, whereas an unaltered collagen deposition did not suggest steatofibrosis. In conclusion, rosiglitazone treatment of diabetic Akita mice induced liver steatosis without, however, progression to more advanced stages of liver disease.
The Rise of Social Assistance in Brazil
Authors: Barrientos Armando
Published: June 2013

The rise of social assistance in Brazil has been remarkable. The 1988 Constitution signalled a renewed ‘social contract’ leading to citizenship‐based social assistance providing guaranteed income to older and disabled people in poverty. Municipal activism in the 1990s extended the provision of direct transfers to all households in poverty through Bolsa Escola and other programmes later consolidated into Bolsa Família. This article studies the origins and evolution of social assistance institutions in Brazil, paying due attention to the role of ideas and politics.
The evolving course of HNF4A hyperinsulinaemic hypoglycaemia—a case series
Authors: McGlacken‐Byrne S. M. , Hawkes C. P. , Flanagan S. E. , Ellard S. , McDonnell C. M. , Murphy N. P.
Published: June 2013

Background

Hepatocyte nuclear factor 4 alpha (HNF4A) gene mutations have a well‐recognized role in maturity‐onset diabetes of the young and have recently been described in congenital hyperinsulinism. A biphasic phenotype has been postulated, with macrosomia and congenital hyperinsulinism in infancy, and diabetes in young adulthood. In this case series, we report three children with HNF4A mutations (two de novo) and diazoxide‐responsive congenital hyperinsulinism, highlighting the potential for ongoing diazoxide requirement and the importance of screening for these mutations even in the absence of family history.

Case reports

All patients presented with macrosomia (mean birthweight 4.26 kg) and hyperinsulinaemic hypoglycaemia soon after birth (median age 1 day). All three (age range 7 months to 11 years 10 months) remain on diazoxide therapy, with dose requirements increasing in one patient. There was no prior family history of diabetes, neonatal hypoglycaemia or macrosomia. Parents were screened for HNF4A mutations post‐diagnosis and one father was subsequently found to have maturity‐onset diabetes of the young.

Conclusions

This case series follows the evolving course of three patients with confirmed HNF4A‐mediated congenital hyperinsulinism, highlighting (1) the variable natural history of these mutations, (2) the potential for prolonged diazoxide requirement, even into adolescence, and (3) the need for screening, regardless of family history.
Risk of pneumonia and pneumococcal disease in people hospitalized with diabetes mellitus: English record‐linkage studies
Authors: Seminog O. O. , Goldacre M. J.
Published: June 2013

Background

The risk of invasive pneumococcal disease is higher in people with diabetes mellitus than those without. People with diabetes should be considered for routine pneumococcal immunization. This policy has been in place in England for more than a decade. We aimed to estimate, at the population level, the current scale of excess risk of pneumococcal disease in patients with diabetes, and whether the risks have decreased in recent years with the introduction of a pneumococcal vaccine.

Methods

We used two data sets of linked hospital admission and death records—the Oxford Record Linkage Study (1963–1998) and all‐England linked hospital episode statistics (1999–2011). As a measure of relative risk, we calculated the rate ratio of pneumococcal disease in cohorts of people hospitalized with diabetes compared with cohorts without a record of diabetes.

Results

The risk of pneumococcal disease in patients hospitalized with diabetes mellitus has declined a little, but it is still high. The all‐ages rate ratio in England declined from 1.92 (95% CI 1.89–1.94) in 1999–2002 to 1.68 (95% CI 1.65–1.71) in 2007–2011. In people aged under 60 years, rate ratios were higher and their decline was more substantial: rate ratios declined from 3.37 (95% CI 3.28–3.46) in 1999–2002 to 2.33 (95% CI 2.21–2.45) in 2007–2011.

Conclusions

Patients admitted to hospital with diabetes mellitus remain at increased risk of pneumococcal infection despite a national immunization policy. Possible explanations for the elevated risk include low vaccine uptake or low effectiveness of available vaccine. Clinicians should be aware of the risk of pneumococcal infection in people with diabetes.
Hepcidin levels in diabetes mellitus and polycystic ovary syndrome
Authors: Sam A. H. , Busbridge M. , Amin A. , Webber L. , White D. , Franks S. , Martin N. M. , Sleeth M. , Ismail N. A. , Daud N. Mat , Papamargaritis D. , Le Roux C. W. , Chapman R. S. , Frost G. , Bloom S. R. , Murphy K. G.
Published: June 2013

Aim

Increased body iron is associated with insulin resistance. Hepcidin is the key hormone that negatively regulates iron homeostasis. We hypothesized that individuals with insulin resistance have inadequate hepcidin levels for their iron load.

Methods

Serum concentrations of the active form of hepcidin (hepcidin‐25) and hepcidin:ferritin ratio were evaluated in participants with Type 2 diabetes (n = 33, control subjects matched for age, gender and BMI, n = 33) and participants with polycystic ovary syndrome (n = 27, control subjects matched for age and BMI, n = 16). To investigate whether any changes observed were associated with insulin resistance rather than insulin deficiency or hyperglycaemia per se, the same measurements were made in participants with Type 1 diabetes (n = 28, control subjects matched for age, gender and BMI, n = 30). Finally, the relationship between homeostasis model assessment of insulin resistance and serum hepcidin:ferritin ratio was explored in overweight or obese participants without diabetes (n = 16).

Results

Participants with Type 2 diabetes had significantly lower hepcidin and hepcidin:ferritin ratio than control subjects (P < 0.05 and P < 0.01, respectively). Participants with polycystic ovary syndrome had a significantly lower hepcidin:ferritin ratio than control subjects (P < 0.05). There was no significant difference in hepcidin or hepcidin:ferritin ratio between participants with Type 1 diabetes and control subjects (P = 0.88 and P = 0.94). Serum hepcidin:ferritin ratio inversely correlated with homeostasis model assessment of insulin resistance (r = –0.59, P < 0.05).

Conclusion

Insulin resistance, but not insulin deficiency or hyperglycaemia per se, is associated with inadequate hepcidin levels. Reduced hepcidin concentrations may cause increased body iron stores in insulin‐resistant states.
Waist circumference is genetically correlated with incident Type 2 diabetes in Mexican‐American families
Authors: Mamtani M. , Kulkarni H. , Dyer T. D. , Almasy L. , Mahaney M. C. , Duggirala R. , Comuzzie A. G. , Blangero J. , Curran J. E.
Published: June 2013

Aims

We aimed to determine the genetic and environmental correlation between various anthropometric indexes and incident Type 2 diabetes with a focus on waist circumference.

Methods

We used the data on extended Mexican‐American families (808 subjects, 7617.92 person‐years follow‐up) from the San Antonio Family Heart Study and estimated the genetic and environmental correlations of 16 anthropometric indexes with the genetic liability of incident Type 2 diabetes. We performed bivariate trait analyses using the solar software package.

Results

All 16 anthropometric indexes were significantly heritable (range of heritabilities 0.24–0.99). Thirteen indexes were found to have significant environmental correlation with the liability of incident Type 2 diabetes. In contrast, only anthropometric indexes consisting of waist circumference (waist circumference, waist–hip ratio and waist–height ratio) were significantly genetically correlated (genetic correlation coefficients: 0.45, 0.55 and 0.44, respectively) with the liability of incident Type 2 diabetes. We did not observe such a correlation for BMI.

Conclusions

Waist circumference as a predictor of future Type 2 diabetes is supported by the finding that they share common genetic influences.
Effect of grazing intensity on the interaction between Shijimiaeoides divinus asonis (Matsumura, 1929) and its attendant ants
Authors: Murata Kouhei , Matsuura Asana
Published: June 2013

This study was carried out in the natural herbaceous grassland of Mt. Aso, which had been almost completely grazed, and which is subjected to routine grassland burning every spring (February or March) to conserve Shijimiaeoides divinus asonis (Matsumura, 1929). We clarify that ants protect the larvae of this butterfly and evaluate the effects of grazing intensity on the attendant ant population. The results obtained are summarized as follows: (i) Five species of attendant ant were identified, with the dominant species being Formica japonica (Motschulsky, 1866) and Camponotus japonicus (Mayr, 1866). (ii) The number of attendant ants decreased at night time; however, only one or two ants attended the larva until the following morning. (iii) Ten species of insect excluding ants and three species of spiders that approached the larva were recorded on the larval host‐plant. Formica japonica and C. japonicus fought off most newcomers of other insects including the natural enemies of these butterfly larvae. (iv) The number of ants in this butterfly habitat under regular grazing intensity was significantly higher than during low grazing intensity and non‐grazing periods. (v) A positive correlation was found between the number of attendant ants and the number of butterfly larvae on the host‐plant. We concluded that the interaction between this butterfly and attendant ants is one of facultative mutualism because the attendant ants protect the butterfly larva. Therefore, the numbers of this butterfly species may decrease if the number of attendant ants decreases due to the cessation of pasturage.
Consequences of proline‐to‐alanine substitutions for the stability and refolding of onconase
Authors: Hacke Mandy , Gruber Tobias , Schulenburg Cindy , Balbach Jochen , Arnold Ulrich
Published: June 2013

Peptidyl‐prolyl isomerization reactions can make for rate‐limiting steps in protein folding due to their high activation energy. Onconase, an unusually stable ribonuclease A homologue from the Northern leopard frog, contains fourtransproline residues in its native state. During the refolding from its guanidine hydrochloride unfolded state, which includes the formation of a folding intermediate, the slowest of the three phases has earlier been attributed to acis‐to‐transpeptidyl‐prolyl isomerization reaction. We thus substituted all four proline residues individually by alanine and investigated the effect of the amino acid substitutions on the folding and stability of the onconase variants. All onconase variants proved to adopt a tertiary structure comparable with that of the wild‐type protein. Although the slow phase was not eliminated for any of the variants, the P43A substitution resulted in an increase in the rate constant of the fast folding phase, i.e. a faster formation of the folding intermediate. This variant also exhibits a significant increase in thermodynamic stability. As residue 43 belongs to those residues that are protected from hydrogen exchange with the solvent in the folding intermediate, the increase in the rate constant and stability of the P43A variant emphasizes the importance of the intermediate for the folding of onconase.

Enzymes

Onconase (EC 3.1.27.5)
Morphology of biogenic iron oxides records microbial physiology and environmental conditions: toward interpreting iron microfossils
Authors: Krepski S. T. , Emerson D. , Hredzak‐Showalter P. L. , Luther G. W. , Chan C. S.
Published: June 2013

Despite the abundance of Fe and its significance in Earth history, there are no established robust biosignatures for Fe(II)‐oxidizing micro‐organisms. This limits our ability to piece together the history of Fe biogeochemical cycling and, in particular, to determine whether Fe(II)‐oxidizers played a role in depositing ancient iron formations. A promising candidate for Fe(II)‐oxidizer biosignatures is the distinctive morphology and texture of extracellular Fe(III)‐oxyhydroxide stalks produced by mat‐forming microaerophilic Fe(II)‐oxidizing micro‐organisms. To establish the stalk morphology as a biosignature, morphologic parameters must be quantified and linked to the microaerophilic Fe(II)‐oxidizing metabolism and environmental conditions. Toward this end, we studied an extant model organism, the marine stalk‐forming Fe(II)‐oxidizing bacterium, Mariprofundus ferrooxydans PV‐1. We grew cultures in flat glass microslide chambers, with FeS substrate, creating opposing oxygen/Fe(II) concentration gradients. We used solid‐state voltammetric microelectrodes to measure chemical gradients in situ while using light microscopy to image microbial growth, motility, and mineral formation. In low‐oxygen (2.7–28 μm) zones of redox gradients, the bacteria converge into a narrow (100 μm–1 mm) growth band. As cells oxidize Fe(II), they deposit Fe(III)‐oxyhydroxide stalks in this band; the stalks orient directionally, elongating toward higher oxygen concentrations. M. ferrooxydans stalks display a narrow range of widths and uniquely biogenic branching patterns, which result from cell division. Together with filament composition, these features (width, branching, and directional orientation) form a physical record unique to microaerophilic Fe(II)‐oxidizer physiology; therefore, stalk morphology is a biosignature, as well as an indicator of local oxygen concentration at the time of formation. Observations of filamentous Fe(III)‐oxyhydroxide microfossils from a ~170 Ma marine Fe‐Si hydrothermal deposit show that these morphological characteristics can be preserved in the microfossil record. This study demonstrates the potential of morphological biosignatures to reveal microbiology and environmental chemistry associated with geologic iron formation depositional processes.
Identification of KIT activating mutations in paediatric solitary mastocytoma
Authors: Ma Deqin , Stence Aaron A , Bossler Aaron B , Hackman Jason R , Bellizzi Andrew M
Published: June 2013

Aims

Mastocytosis is an abnormal mast cell proliferation involving one or more organs, in particular the skin and bone marrow. In children, disease is usually limited to the skin, with three distinct clinical presentations: urticaria pigmentosa, diffuse cutaneous mastocytosis and solitary mastocytoma. Although the KIT D816V mutation is typically found in adult‐onset mastocytosis, it is less commonly seen in childhood‐onset mastocytosis, and the frequency of KIT mutations in paediatric solitary mastocytoma is poorly documented.

Methods and results

In this study we analysed KIT exons 8, 9, 11, 13 and 17 in nine cases of paediatric solitary mastocytoma using a laboratory‐developed Sanger sequencing assay. A KIT mutation was identified in six cases (67%), including three with the D816V mutation typical of adult‐onset disease, and another three with an internal tandem duplication (p.A502_Y503dup) in exon 9, previously described in gastrointestinal stromal tumour.

Conclusions

Paediatric solitary mastocytoma is frequently associated with KIT activating mutations, in keeping with a clonal process. KIT mutational status appears insufficient to explain the divergent biology of childhood and adult‐onset disease.
The effect of medicated, sugar‐free chewing gum on plaque and clinical parameters of gingival inflammation: a systematic review
Authors: Keukenmeester RS , Slot DE , Putt MS , Van der Weijden GA
Published: June 2013

Objective

This study aimed to systematically review the present literature to establish the clinical effect of medicated, sugar‐free chewing gum on plaque indices and parameters of gingival inflammation.

Materials and methods

MEDLINE–PubMed, Cochrane CENTRAL and EMBASE databases were searched up to April 2012 to identify appropriate studies. Included studies used an intervention of medicated, sugar‐free chewing gum containing antimicrobial agents or herbal extracts compared with a control gum. Plaque and gingivitis scores were selected as outcome variables.

Results

Independent screening of 594 unique titles and abstracts identified 10 non‐brushing and four brushing studies that met the eligibility criteria. Means and standard deviations were extracted. A sufficient number of studies evaluated chlorhexidine gum to perform a meta‐analysis. Although this review provides evidence for the comparative effectiveness of chewing gums containing various ingredients, the results must be weighed carefully against the methods that were used to assess their outcomes.

Conclusion

Most of the chewing gums with antimicrobial agents or herbal extracts were shown to have a positive effect with respect to plaque and gingivitis scores. The most compelling evidence was provided for chewing gum containing chlorhexidine. Meta‐analysis and individual results indicate a beneficial effect of chlorhexidine on plaque inhibition. However, GRADE evidence profile shows that the recommendation to use CHX‐gum to reduce plaque scores in the absence of brushing is considered to be ‘weak’. Other ingredients with positive outcomes on plaque scores are eucalyptus, acacia, funoran, Pycnogenol and mastic. Limited data with respect to gingivitis scores were available, and the following agents showed a positive effect: magnolia, eucalyptus and CHX.
Joint optimization of pricing and planning decisions in divergent supply chain
Authors: Guajardo Mario , Kylinger Martin , Rönnqvist Mikael
Published: June 2013

In divergent supply chains, such as in the oil industry, processing raw materials results in an outflow of multiple products. Final products are stored at international depots, from where they are ready to be shipped to the markets. Even if one company controls the entire chain, when production and sales organizations are decoupled, a relevant problem is to determine the internal prices of products at depots for achieving coordination. We propose an optimization model involving pricing and production decisions, and several constraints commonly used in divergent chains. In our approach, the producer incorporates the sellers’ behavior by expressing demand as a function of the internal price. As a result, our model serves as a coordination mechanism in trying to get an overall coordinated integrated solution in a decoupled reality. Numerical examples in single and multiple periods problems show the advantages of our approach over cost‐based methods.
A heuristic and an exact method for the gate matrix connection cost minimization problem
Authors: De Giovanni L. , Massi G. , Pezzella F. , Pfetsch M.E. , Rinaldi G. , Ventura P.
Published: June 2013

In many applications, a sequencing of patterns (electronic circuit nodes, cutting patterns, product orders, etc.) has to be found in order to optimize some given objective function, giving rise to the so‐called open stack problems. We focus on a problem related to the optimization of gate matrix layouts: electronic circuits are obtained by connecting gates and one seeks a gate layout permutation that minimizes connection costs under restrictions on the circuit area. In the literature, the connection costs and circuit area are also known as time of open stacks and maximum number of open stacks, respectively. We propose a genetic algorithm providing heuristic solutions and a branch‐and‐cut algorithm based on a new linear integer programming formulation that represents, to the best of our knowledge, the first exact method proposed in the literature. The algorithms have been tested on real instances and on data sets from the literature. The computational results give evidence that the proposed methods provide solutions that improve the ones found by the approaches presented in the literature.
Key to the eggs of the equid stomach bot flies Gasterophilus Leach 1817 (Diptera: Gasterophilidae) utilizing scanning electron microscopy
Authors: COGLEY THOMAS P.
Published: June 2013

Abstract. A key to the eggs of the equid stomach bot flies is presented. Scanning electron photomicrographs of eggs are used to illustrate differences among the eight Gasterophilus species. The eggs include those of G.haemorrhoidalis (Linnaeus, 1758), G.inermis (Brauer, 1858), G.intestinalis (De Geer, 1776), G.meridionalis (Piller and Evans, 1926), G.nasalis (Linnaeus, 1758), G.nigricornis (Loew, 1863), G.pecorum (Fabricius, 1794), and G.ternicinctus Gedoelst, 1912. The eggs of G.meridionalis and G.ternicinctus are shown for the first time. Egg profile is the same for a particular species and is used as a key character for egg identification. Colour of eggs is used in some couplets but only as a supplemental character. Absence or presence of striae on the eggs is used as a primary contrasting character to separate G.pecorum from the other seven species. Shape of the striae varies on eggs of the same species, even those dissected from the same specimen, and is therefore deemed an unreliable taxonomic character for further separation of the Gasterophilus species. Eggs of the same species taken from specimens throughout the world appear the same in profile. Two sets of eggs require close inspection for adequate identification: G.inermis and G.nigricornis separated primarily by the shape of the microphylar region; and G.intestinalis and G.ternicinctus separated by the shape of the egg ventrum. All other eggs have very unique and distinctive profiles. Only G.pecorum was found to possess the Type‐II egg attachment organ (AO) used for adherence of the egg to plants or flat surfaces. The eggs of the remaining seven species possess a Type‐I AO used to attach the eggs to hair shafts. The type of AO and the degree that the Type‐I AO is extended posteriorly were used as key characters in the first and second couplet respectively.
Morphometric discrimination among females of sibling species of Aconophorini (Homoptera: Membracidae)
Authors: DIETRICH CHRISTOPHER H. , EMIGH TED H. , DEITZ LEWIS L.
Published: June 2013

Abstract.Keys to species of auchenorrhynchous Homoptera are often based on male features, leaving no means for identifying females other than association with males. As a possible solution to this problem, we examined the use of linear discriminant functions derived from morphometric data (ten linear measurements among homologous body landmarks) for distinguishing females in two groups of sibling species in the Neotropical treehopper tribe Aconophorini (Membracidae: Membracinae): (1)Calloconophora caliginosa(Walker) andC.pinguis(Fowler); and (2)Guayaquila minuta(Fowler),G.venezuelensisDietrich, and Central and South American populations ofG.pallescens(Stål). Samples of female specimens identified by association with males were used to derive the discriminant functions. Performance of these discriminant functions as evaluated by jackknifing the data was as follows: 98.11% of the specimens in the first group correctly identified using a combination of three measurements, and 94.94% of the specimens in the second group correctly identified using a combination of ten measurements.
Pameridea (Hemiptera: Miridae): Predaceous bugs specific to the highly viscid plant genus Roridula
Authors: DOLLING W. R. , PALMER J. M.
Published: June 2013

Abstract. The South African genus Pameridea and its two species are redescribed. The tribe Pamerideini, founded for this genus only, is removed from synonymy with Mirini (subfamily Mirinae) and transferred to Dicyphini (subfamily Bryocorinae), falling as a synonym of the subtribe Dicyphina. The bugs live only on intensely viscid small shrubs of the genus Roridula. This plant genus is the only member of its family but the bug genus is closely related to two widespread tropical dicyphine genera.
Fatal Cutaneous Squamous Cell Carcinoma in a Forty‐Three‐Year‐Old Male
Authors: MOHLE JANET , NICKOLOFF B. J.
Published: June 2013

Abstract
A 43‐year‐old patient with a history of squamous cell carcinoma (SCC) of the lip, multiple actinic keratoses, and multiple sequential SCC on sun‐exposed areas of his skin developed a subcutaneous nodule of SCC in an area where a cutaneous SCC had been excised 1 year previously. At the time of the subcutaneous nodule there was no evidence of metastases; 5 months later he had metastatic bone disease as well as apparent metastases to myocardium, pericardium, and pleura. The patient is notable for the young age at primary diagnosis of SCC, the fulminant lethal course of a tumor which is generally considered curable, and a family history to which SCC occurred over three generations.
Surgical Treatment for Aggressive Giant Keratoacanthoma of the Face
Authors: PAGANI WILLY A. , LORENZI GIUSEPPE , LORUSSO DIEGO
Published: June 2013

Abstract
A case of aggressive giant keratoacanthoma on the right temple region is described. Histopathologic examination was not definitive for keratoacanthoma, so that clinical considerations were helpful for diagnosis. The neoplasm was treated successfully with surgical excision and immediate repair with skin graft, in spite of one narrow peripheral area of residual disease on the wound surface after resection.
Merkel Cell Carcinoma: A Challenge
Authors: STAWOWY LALA M. , KRULL EDWARD A. , MAEDA KOICH
Published: June 2013

Abstract. A 70‐year‐old man presented with an enlarging, recurrent tumor of the left buttock which, on initial biopsies, was interpreted as a histiocytic malignant lymphoma. Further biopsies showed numerous monomorphic, hyperchromatic, noncohesive cells, arranged in compact sheets, throughout the dermis, the fat, and the underlying muscle. Neuron specific enolase stain for neuroendocrine granules was positive. Electron microscopy showed cytoplasmic perinuclear microfilaments and round membrane‐bound dense core granules. The histologic, enzymatic, and ultrastructural findings confirmed the diagnosis of Merkel cell carcinoma. Early diagnosis and treatment are imperative for a favorable outcome.
Psoriasis: Disease of Epidermis or Dermis?
Authors: FORTIER LAWRENCE J. , MIKHAIL GEORGE R.
Published: June 2013

Abstract. Psoriasis is considered a disease of the epidermis. Two lesions of basal cell carcinoma in patches of psoriasis were excised by Mohs microscopically controlled surgery. As healing occurred by second intention, reepithelization of the surface must have taken place from the surface epidermis of the surrounding psoriatic skin. The scarred areas remained free of psoriasis for many years. This emphasizes the role of a dermal factor in the development of psoriasis.
Spontaneous Regression of Metastatic Malignant Melanoma
Authors: MIKHAIL GEORGE R. , GORSULOWSKY DAVID C.
Published: June 2013

Abstract. Spontaneous regression of metastatic malignant melanoma is rare. A case is presented here. The primary lesion, a lentigo maligna melanoma of the face, recurred after excision and metastasized to the parotid and upper cervical lymph nodes, and to the lungs. The patient declined further therapy. There was no clinical or radiologic evidence of metastasis 1 year later.
Residents' Corner: Subungual Mucinous Pseudocyst
Authors: WESTROM DALE R. , FINDLAY ROBERT F.
Published: June 2013

Abstract. A rare presentation of an entirely subungual mucinous pseudocyst is described.
The Forehead V‐to‐T Plasty (Dieffenbach's Winged V‐Plasty)
Authors: FIELD LAWRENCE M.
Published: June 2013

Abstract. The principles of the V‐to‐T plasty (Dieffenbach's winged V‐plasty) are adaptable to many regions of the forehead. This paper demonstrates the use of the V‐to‐T plasty to reconstruct an extensive area of the lower central forehead and glabella following excision for basal cell carcinomatosis. Dual hemi‐forehead advancement‐rotation flaps were used in a single‐stage reconstruction. The same technique adapts to other forehead and facial areas as well.
The Significance of Transepithelial Elimination in Dermatologic Surgery
Authors: GOETTE DETLEF K.
Published: June 2013

Abstract. Transepithelial elimination (TE) was found to be an important physiologic mechanism of ridding the skin of foreign material introduced during cutaneous surgery, as evidenced in the histologic examination of re‐excision specimens. Thus, TE of suture material, Monsel's granulomas, and starch granules are pictorially documented in several brief case reports.
Residents' Corner: Cryosurgery of Clear Cell Acanthoma
Authors: FERNANDEZ‐OBREGON ADOLFO C.
Published: June 2013

Abstract. A case is presented of an epidermal tumor occurring in an 84‐year‐old male which had been treated for many years as a chronic dermatitis. Following histologic confirmation of clear cell acanthoma, cryosurgery was attempted, resulting in a complete resolution of the tumor with no recurrence at 6 months.
Tumor Stage Mycosis Fungoides in a Patient Treated with Long‐Term Corticosteroids for Asthma and Atopic‐Like Dermatitis
Authors: ABEL E.A. , NICKOLOFF B.J. , SHELBY D.M. , WATSON W. , WOOD G.S.
Published: June 2013

Abstract. An association between atopy and the Sezary syndrome has been recognized in some patients. Our case represents an association between adult‐onset asthma and atopic‐like dermatitis, markedly elevated IgE levels, and the development of tumor stage mycosis fungoides (MF) in a patient receiving long‐term corticosteroid therapy. The chronic eczematous dermatitis may have represented evolving MF in which the specific diagnosis was delayed by treatment with topical and systemic corticosteroids until advanced tumor stage disease. This case, in conjunction with prior reports, suggests that an atopic diathesis can be associated with both leukemic and nonleukemic forms of cutaneous T‐cell lymphoma.
Identification of Basal Cell Carcinomas by means of Monoclonal Antibodies C50 and C241
Authors: NILSSON L. Å. , GISSLÉN HÅKAN , LINDHOLM A. , LINDHOLM L. , MOBACKEN H.
Published: June 2013

Abstract. The monoclonal antibodies C50 and C241 with specificities for the carcinoma‐associated carbohydrate structures sialylated Lea and sialosyllactotetraose, respectively, were used in the indirect immunofluorescent test for demonstration of malignant cells in patients with basal cell carcinoma (BCC). Among a total of 36 patients with BCC, 33 were positive with the MAb C50, and 30 with the MAb C241. All of five patients with premaiig‐nant conditions were positive with both antibodies, whereas none of 31 control individuals (biopsies from normal skin or from patients with non‐malignant conditions) showed a positive reaction. It is suggested that the technique described may provide a convenient tool for evaluation of samples obtained by microscopically controlled surgery of BCC as well as being an adjunct to conventional light microscopy in pathologic‐anatomic diagnosis of potentially malignant disease of the skin.
Conventional Grafting Combined with Minigrafting: A New Approach
Authors: BRANDY DOMINIC A.
Published: June 2013

Abstract. Using a combination of 4.0‐mm conventional Orentreich punch grafts and minigrafts, the author describes a methodology to achieve a very uniform, untufted look which is usually the end result of conventional grafting alone. Advantages and disadvantages are detailed.
Syringoid Eccrine Carcinoma
Authors: WEBER PAUL J. , GRETZULA JOSEPH C. , GARLAND LARRY D. , HEVIA OSCAR , MENN HENRY
Published: June 2013

Abstract. Syringoid eccrine carcimonas (SECs) are rare adnexal neoplasms that may display aggressive local recurrence and occasional metastases. This report describes three cases of SEC treated by Mohs micrographic surgery.
Techniques for Split‐Thickness Skin Grafting
Authors: SKOUGE JOHN W.
Published: June 2013

Abstract This article discusses split‐thickness skin grafting techniques with emphasis on the use of various electric dermatomes. Indications for grafting, donor and recipient site considerations, as well as complications will be discussed.
Surgical Treatment of Livedo Vasculitis
Authors: TEMAN J. , INGBER A. , ROTHEM A. , BEN‐BASSAT M.
Published: June 2013

Abstract Surgical treatment for livedo vasculitis as a primary approach is not mentioned in the literature. A young female patient suffering from livedo vaculitis (atrophie blanche) was admitted with huge ulcerations and pre‐ulcerative, infarcted skin areas of both feet and ankles. The lesions were promptly excised and skin grafted with excellent results. The course of treatment, including several surgical procedures, is described.
Immunogenicity of Injectable Collagen Implants
Authors: SELLEM PHILIPPE H. , CARANZAN FRANCOIS R. , BENE MARIE C. , FAURE GILBERT C.
Published: June 2013

The presence of antibodies to bovine and human collagens used in injectable collagen implants (ICI) was investigated in 103 normal sera. Significant levels of spontaneous nonprecipitin antibodies were observed, suggesting that immunization to ICI compounds may preexist even in the absence of connective tissue disease.
Free Laminar Thin Band Graft— A Surgical Therapeutic Variant in the Treatment of Leg Ulcers
Authors: VILALTA ANTONIO , MOLGÓ MONTSERRAT , MARTÍ ROSA M. , MASCARÓ JOSÉ M.
Published: June 2013

Abstract. For the past 2 years, we have been using a surgical technique for the treatment of leg ulcers caused by chronic venous insufficiency. This consists of a type of graft biologically and technically intermediate between Reverdin and Thiersh's types. We have named it the “free laminar thin band graft.” In contrast to the Thiersh graft, this simple surgical technique requires little equipment, and it can be done quickly and easily as an office procedure, with little risk to the patient. In addition, it is a low cost procedure. In our experience with this technique, healing time is shorter and lesions recur later than with the Reverdin graft. The authors describe the surgical method and report a clinical case.