Nigricans

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Nigricans

  • acanthosis nigrican
  • rhizopus nigrican


  • Selected Abstracts


    Insulin resistance Type A and short 5th metacarpals

    DIABETIC MEDICINE, Issue 6 2003
    Vinod K. Patel
    Abstract Background/aims Insulin resistance is associated with a number genetic syndromes and a variety of defects of insulin action. Methods We describe three members of an extended family spanning two generations with insulin resistance Type A and short 5th metacarpals. The proband had secondary amenorrhoea, male pattern hair distribution, acne, hirsutism, deep voice, acanthosis nigricans, polycystic ovaries, diabetes, features of acromegaly, raised creatine kinase and triglyceride levels and short 5th metacarpals. Her growth hormone, adrenal steroid and testosterone levels were normal. The proband's daughter had severe acne, hirsutism, acanthosis nigricans, polycystic ovaries, raised triglyceride, glucose and testosterone level short metacarpals and normal insulin receptor gene. The proband's son had a muscular build, raised creatine kinase, hypertriglyceridaemia and short 5th metacarpals. His fasting insulin levels were normal but pro-insulin was raised. Result/conclusion There are many familial and genetic syndromes associated with insulin resistance. This family was diagnosed as having insulin resistance Type A. This family does not conform entirely to any of the previously described syndromes and a number of family members have the phenotype of short 5th metacarpals, which appears to be associated with the features of insulin resistance Type A. Diabet. Med. 20, 500,504 (2003) [source]


    Type 2 diabetes mellitus in UK children , an emerging problem

    DIABETIC MEDICINE, Issue 12 2000
    S. Ehtisham
    SUMMARY Aims Type 2 diabetes mellitus has never previously been described in UK children, although an increasing incidence in childhood is recognized in international studies. The prevalence of obesity in UK children is increasing and is a recognized risk factor for the development of diabetes. The aim of this study was to identify and characterize children with Type 2 diabetes in the West Midlands and Leicester. Methods Children were identified by contacting paediatricians responsible for diabetes in five hospitals. Details were collected on demographics, mode of presentation, investigations and treatment on a standard proforma. Results Eight girls were identified with Type 2 diabetes, aged 9,16 years and who were of Pakistani, Indian or Arabic origin. They were all overweight (percentage weight for height 141,209%) and had a family history of diabetes in at least two generations. They presented insidiously with hyperglycaemia and glycosuria without ketosis and five were asymptomatic. Islet cell antibodies measured in seven patients were negative. Four had acanthosis nigricans which is a cutaneous marker of insulin resistance and the other four had high plasma levels of insulin and/or C peptide. These patients are distinct from those with maturity-onset diabetes of the young (MODY). All were initially managed with dietary measures, seven have been treated with oral anti-diabetic agents of whom two have subsequently required insulin. Conclusions These are the first UK case reports of Type 2 diabetes in children. Paediatricians need to be aware of the risk of Type 2 diabetes developing in childhood in high-risk ethnic groups, particularly in association with obesity and a positive family history. [source]


    Demographics of the spawning aggregations of four catostomid species in the Savannah River, South Carolina and Georgia, USA

    ECOLOGY OF FRESHWATER FISH, Issue 2 2008
    T. B. Grabowski
    Abstract,,, Differences in the life history strategies employed by otherwise ecologically similar species of a fish assemblage may be an important factor in the coexistence of these species and is an essential consideration in the conservation and management of these assemblages. We collected scales to determine age and growth of four species of the catostomid assemblage (northern hogsucker Hypentelium nigricans, spotted sucker Minytrema melanops, notchlip redhorse Moxostoma collapsum and robust redhorse Moxostoma robustum) of the Savannah River, Georgia,South Carolina in spring 2004 and 2005. Robust redhorse was the largest species; reaching sexual maturity at an older age and growing faster as a juvenile than the other species. Spotted sucker did not achieve the same size as robust redhorse, but reached sexual maturity at younger ages. Notchlip redhorse was intermediate between the abovementioned two species in age at maturity and size. Northern hogsucker was the smallest species of the assemblage and reached the sexual maturity at the age of three. Both robust redhorse and spotted sucker were sexually dimorphic in size-at-age. The range of life history strategies employed by Savannah River catostomids encompasses the range of life history strategies exhibited within the family as a whole. [source]


    NtKTI1, a Kunitz trypsin inhibitor with antifungal activity from Nicotiana tabacum, plays an important role in tobacco's defense response

    FEBS JOURNAL, Issue 19 2010
    Hao Huang
    A cDNA library from tobacco inoculated with Rhizoctonia solani was constructed, and several cDNA fragments were identified by differential hybridization screening. One cDNA clone that was dramatically repressed, NtKTI1, was confirmed as a member of the Kunitz plant proteinase inhibitor family. RT-PCR analysis revealed that NtKTI1 was constitutively expressed throughout the whole plant and preferentially expressed in the roots and stems. Furthermore, RT-PCR analysis showed that NtKTI1 expression was repressed after R. solani inoculation, mechanical wounding and salicylic acid treatment, but was unaffected by methyl jasmonate, abscisic acid and NaCl treatment. In vitro assays showed that NtKTI1 exerted prominent antifungal activity towards R. solani and moderate antifungal activity against Rhizopus nigricans and Phytophthora parasitica var. nicotianae. Bioassays of transgenic tobacco demonstrated that overexpression of NtKTI1 enhanced significantly the resistance of tobacco against R. solani, and the antisense lines exhibited higher susceptibility than control lines towards the phytopathogen. Taken together, these studies suggest that NtKTI1 may be a functional Kunitz trypsin inhibitor with antifungal activity against several important phytopathogens in the tobacco defense response. [source]


    Abundance, diversity, and activity of microbial assemblages associated with coral reef fish guts and feces

    FEMS MICROBIOLOGY ECOLOGY, Issue 1 2010
    Steven Smriga
    Abstract Feces and distal gut contents were collected from three coral reef fish species. Bacteria cell abundances, as determined via epifluorescence microscopy, ranged two orders of magnitude among the fishes. Mass-specific and apparent cell-specific hydrolytic enzyme activities in feces from Chlorurus sordidus were very high, suggesting that endogenous fish enzymes were egested into feces. Denaturing gradient gel electrophoresis profiles of 16S rRNA genes were more similar among multiple individuals of the surgeonfish Acanthurus nigricans than among individuals of the parrotfish C. sordidus or the snapper Lutjanus bohar. Analyses of feces-derived 16S rRNA gene clones revealed that at least five bacterial phyla were present in A. nigricans and that Vibrionaceae comprised 10% of the clones. Meanwhile, C. sordidus contained at least five phyla and L. bohar three, but Vibrionaceae comprised 71% and 76% of the clones, respectively. Many sequences clustered phylogenetically to cultured Vibrio spp. and Photobacterium spp. including Vibrio ponticus and Photobacterium damselae. Other Vibrionaceae -like sequences comprised a distinct phylogenetic group that may represent the presence of ,feces-specific' bacteria. The observed differences among fishes may reflect native gut microbiota and/or bacterial assemblages associated with ingested prey. [source]


    Carbon sources of Amazonian fisheries

    FISHERIES MANAGEMENT & ECOLOGY, Issue 4 2000
    E. Benedito-Cecilio
    Variation in the seasonal and spatial isotopic composition of plant C4 (aquatic macrophytes) and C3 (forest, C3 aquatic macrophytes and algae), and that of fish [Prochilodus nigricans Agassiz, Mylossoma duriventre (Cuvier), Colossoma macropomum (Cuvier), Semaprochilodus insignis (Schomburgk) and S. taeniurus Steindachner in the Amazon floodplain were analysed to test whether the fisheries deliver plant carbon to the population of Manaus in the same proportion as it is available in the floodplain. The contribution of C4 plants was significantly lower in 13C during the season of high water levels and increased toward the west of the basin. Mylossoma duriventre and C. macropomum changed ,13C levels, while the ,13C of P. nigricans and C. macropomum shifted spatially. The contribution of C4 to the fisheries yield was small. C3 plants (excluding phytoplankton) also contributed less than expected. This was explained by the importance of detritivores to the yield of the fisheries and the dependence of these species on algal carbon. [source]


    Importance of the Straits of Florida spawning ground to Atlantic sailfish (Istiophorus platypterus) and blue marlin (Makaira nigricans)

    FISHERIES OCEANOGRAPHY, Issue 6 2009
    DAVID E. RICHARDSON
    Abstract Much of the uncertainty in managing highly migratory pelagic species results from the scarcity of fisheries-independent data relevant to determining long-term trends in abundance, migratory movements, and the relative importance of different spawning grounds. To address these issues, we used an ichthyoplankton-based method to quantify the overall level of spawning of sailfish (Istiophorus platypterus) and blue marlin (Makaira nigricans) in the Straits of Florida (SF). We estimated that during the 2 years (2003,2004) of the study, 4.60 × 1011 sailfish eggs and 4.49 × 1011 blue marlin eggs were produced on an annual basis in this region. These egg production values, when combined with estimates of annual fecundity for each species and the most recent stock assessment estimate of total biomass, indicate that about 2.1% of Western Atlantic sailfish spawning and 1.6% of Atlantic-wide blue marlin spawning occurs in the SF. Additionally, pop-up satellite tags deployed on sailfish at the start of the spawning season revealed their short residency times in the SF, suggesting that a large (,13%) transient portion of the sailfish population is responsible for the SF egg production. Overall, this study provides a critically needed fisheries-independent method of quantifying spatial and temporal trends in the abundance of highly migratory species. The application of this methodology in the SF indicated that above-average levels of sailfish and blue marlin spawning occur in this area and, possibly more importantly, that the SF is a migratory bottleneck for these species. [source]


    Environmental and spatial effects on the distribution of blue marlin (Makaira nigricans) as inferred from data for longline fisheries in the Pacific Ocean

    FISHERIES OCEANOGRAPHY, Issue 6 2008
    NAN-JAY SU
    Abstract Blue marlin is distributed throughout tropical and temperate waters in the Pacific Ocean. However, the preference of this species for particular habitats may impact its vulnerability to being caught. The relationship between spatio-temporal patterns of blue marlin abundance and environmental factors is examined using generalized additive models fitted to catch and effort data from longline fisheries. The presence of blue marlin, and the catch rate given presence, are modeled separately. Latitude, longitude, and sea-surface temperature explain the greatest proportion of the deviance. Spatial distributions of relative density of blue marlin, based on combining the probability of presence and relative density given presence, indicate that there is seasonal variation in the distribution of blue marlin, and that the highest densities occur in the tropics. Seasonal patterns in the relative density of blue marlin appear to be related to shifts in SST. The distribution and relative abundance of blue marlin are sufficiently heterogeneous in space and time that the results of analyses of catch and effort data to identify ,hotspots' could be used as the basis for time-area management to reduce the amount of blue marlin bycaught in longline fisheries. [source]


    Vertical habitat utilization by large pelagic animals: a quantitative framework and numerical method for use with pop-up satellite tag data

    FISHERIES OCEANOGRAPHY, Issue 3 2006
    JIANGANG LUO
    Abstract A quantitative framework and numerical methodology were developed to characterize vertical habitat utilization by large pelagic animals and to estimate the probability of their capture by certain types of fishing gear. Described are the steps involved to build ,vertical habitat envelopes' from data recovered from an electronically tagged blue marlin (Makaira nigricans) as well as from a longline fishing gear experiment employing temperature,depth recording devices. The resulting vertical habitat envelopes, which integrate depth and temperature preferences of tagged fish, are conducive for comparative studies of animal behavior and for calculation (and visualization) of degrees of overlap , be it among individuals, species or fishing gear. Results of a computer simulation evaluation indicated our numerical procedure to be reliable for estimating vertical habitat use from data summaries. The approach appears to have utility for examining pelagic longline fishing impacts on both target and non-target species and could point to ways of reducing bycatch via modification of fishing strategy or gear configuration. [source]


    Utilization of essential oil as natural antifungal against nail-infective fungi

    FLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2002
    Mamta Patra
    Abstract During antifungal screening of some essential oils, Foeniculum vulgare exhibited the strongest activity, completely inhibiting the mycelial growth of the nail-infective fungi, Trichophyton rubrum, T. mentagrophytes and Scytalidium dimidiatum. The essential oil was found to be fungicidal at 0.2, 0.4 and 0.5 µl/ml concentrations. The oil was efficiently active against heavy doses of inoculum at minimum fungicidal concentrations. The fungicidal activity of the oil was found to be thermostable up to 80 °C, with no descramble decrease in activity after 48 months of storage. The oil also showed a broad fungitoxic spectrum, inhibiting the mycelial growth of other nail-infective fungi, viz. Aspergillus flavus, A. fumigatus, A. niger,A. ustus, Candida albicans, Epidermophyton floccosum, Microporum audouinii, M. canis, M. gypseum, M. nanum, Rhizopus nigricans, Trichophyton tonsurans and T. violaceum. Moreover, it did not exhibit any adverse effects on mammalian skin and nails up to 5% concentration. As such, the oil has a potential use as an effective herbal chemotherapeutic after undergoing successful clinical trials. Copyright © 2002 John Wiley & Sons, Ltd. [source]


    Oral acanthosis nigricans, tripe palms and sign of leser-trélat in a patient with gastric adenocarcinoma

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 7 2004
    M. Pentenero DDS
    Acanthosis nigricans (AN), tripe palms (TP) and the sign of Leser-Trélat (LT) may be seen with the presence of malignancy. Acanthosis nigricans may have a mucocutaneous localization involving the oral mucosa with papillomatous and verrucous lesions usually on the lips and buccal mucosa. These paraneoplastic dermatoses are generally linked with intra-abdominal malignancy, most often gastric adenocarcinoma. Improvement of the associated dermatoses after the treatment of the malignancy has been frequently observed. We report the case of a 53-year-old man suffering from advanced gastric adenocarcinoma, in which metastases seemed to sustain all three paraneoplastic dermatoses. To the best of our knowledge this is the first case of a patient showing manifestations of all three paraneoplastic dermatoses. Patients presenting with this set of dermatoses should be suspected to harbor an occult malignancy, or have persistence of a known malignancy. [source]


    Original article: Antifungal activities of cinnamon oil against Rhizopus nigricans, Aspergillus flavus and Penicillium expansum in vitro and in vivo fruit test

    INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2010
    Yage Xing
    Summary The postharvest pathogens such as R. nigricans, A. flavas and P. expansum are the causal agents of jujube or orange fruit, therefore, in vitro and in vivo antifungal activities of cinnamon oil to inactivate these fungi were investigated. Cinnamaldehyde is the main constituent of cinnamon oil. The minimum inhibitory concentrations of cinnamon oil against Rhizopus nigricans, Aspergillus flavus and Penicillium expansum were 0.64% (v/v), 0.16% (v/v) and 0.16% (v/v), respectively. The antifungal activity of cinnamon oil against A. flavus and P. expansum was stronger than that against R. nigricans and the activity was improved with increasing its concentration. In an in vivo study, cinnamon oil with concentrations of 2.0% (v/v) and 3.0% (v/v) showed complete control the growth of fungi in wound-inoculated Lingwu Long Jujube and Sand Sugar Orange fruits. These results revealed that cinnamon oil has a good potential to be as a natural antifungal agent for fruit applications. [source]


    Screening of glucose/insulin metabolic alterations in men with multiple skin tags on the neck

    JOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 10 2008
    Emilio Sudy
    Summary Multiple skin tags appear associated with abnormalities in glucose/insulin metabolism. Clinical and metabolic glucose/insulin characteristics of men with multiple (8 or more) skin tags on the neck were compared with a control group with few or none. Both groups were divided in two subgroups according to normal or abnormal laboratory findings. In the study subgroup with normal laboratory findings the number of skin tags varied from 8,33, whereas in those with abnormal laboratory findings the range was 9,65. Eight or more skin tags were related with statistically significant laboratory glucose/insulin abnormalities: basal hyperinsulinemia (p<0.002), postprandial hyperinsulinemia (p<0.003), and postprandial hyperglycemia (p<0.01). In the multiple skin tag group 77 % had diverse laboratory abnormalities, including insulin resistance, basal hyperinsulinemia, postprandial hyperinsulinemia, glucose intolerance or type 2 diabetes, in contrast with the control group, where only 33 % showed laboratory abnormalities. One-third of the study group had acanthosis nigricans. Only 15 % of patients with metabolic abnormalities did not show any cutaneous expression of glucose/insulin alterations (9 or more skin tags on the neck, acanthosis nigricans, or waist circumference greater than 95 cm). Multiple skin tags were more sensitive than acanthosis nigricans in identifying those with alterations in the glucose/insulin metabolism (77 vs. 32 % respectively), although less specific (68 vs.100%). Multiple skin tags should raise suspicion of insulin resistance or hyperinsulinemia. [source]


    Phylogeography of the northern hogsucker, Hypentelium nigricans (Teleostei: Cypriniformes): genetic evidence for the existence of the ancient Teays River

    JOURNAL OF BIOGEOGRAPHY, Issue 8 2003
    Peter B. Berendzen
    Abstract Aim, To assess the roles of dispersal and vicariance in shaping the present distribution and diversity within Hypentelium nigricans, the northern hogsucker (Teleostei: Cypriniformes). Location, Eastern United States. Methods, Parsimony analyses, Bayesian analyses, pairwise genetic divergence and mismatch plots are used to examine patterns of genetic variation across H. nigricans. Results, Species relationships within the genus Hypentelium were consistent with previous hypotheses. However, relationships between haplotypes within H. nigricans revealed two deeply divergent groups, a clade containing haplotypes from the New and Roanoke rivers (Atlantic Slope) plus Interior Highlands and upper Mississippi River and a clade containing haplotypes from the Eastern Highlands, previously glaciated regions of the Ohio and Wabash rivers, and the Amite and Homochitto rivers of south-western Mississippi. Main conclusions, The phylogenetic history of Hypentelium was shaped by old vicariant events associated with erosion of the Blue Ridge and separation of the Mobile and Mississippi river basins. Within H. nigricans two clades existed prior to the Pleistocene; a widespread clade in the pre-glacial Teays-Mississippi River system and a clade in Cumberland and Tennessee rivers. Pleistocene events fragmented the Teays-Mississippi fauna. Following the retreat of the glaciers H. nigricans dispersed northward into previously glaciated regions. These patterns are replicated in other clades of fishes and are consistent with some of the predictions of Mayden's (Systematic Zoology, 37, 329, 1988) pre-Pleistocene vicariance hypothesis. [source]


    Impacts of increased nitrogen supply on Norwegian lichen-rich alpine communities: a 10-year experiment

    JOURNAL OF ECOLOGY, Issue 3 2005
    ELI FREMSTAD
    Summary 1Species cover was tested during a 10-year fertilization experiment in the low-alpine Cetrarietum nivalis community and the middle-alpine Phyllodoco-Juncetum trifidi community in the Dovre mountains of south-central Norway. Nitrogen was added at 7, 35 and 70 kg N ha,1 year,1, with the highest dose corresponding to approximately 3.5 times the annual deposition in south-west Norway. 2Both communities are dominated by lichens (Cladonia spp. and Cetraria spp., respectively), have a patchy structure and are ,conservative' as regards species content. 3Lichens, which showed a decrease in cover and size, and after some years developed discoloured thalli, are the best organisms for monitoring changes in alpine vegetation that is exposed to increased nitrogen deposition. The most sensitive species in Cetrarietum nivalis appeared to be Alectoria nigricans and Cetraria ericetorum, but more abundant species (Cladonia mitis, C. stellaris and Cetraria nivalis) are likely to be more reliable indicators. Cetraria delisei seems to be a reliable indicator species for monitoring in Phyllodoco-Juncetum trifidi. 4Fertilization had no significant effect on the vascular plants (dwarf shrubs and a few graminoids) in either community, except for Festuca ovina, the cover of which increased slightly. 5Nitrogen pollution may affect oligotrophic, alpine communities differently, depending on their species composition and horizontal structure (patchiness). 6It is suggested that other factors, such as climate, soil properties and community structure, may be more important than long-range nitrogen pollution for determining species composition and species cover in many of the oligotrophic, alpine communities in southern Norway. However, in lichen-rich communities, critical loads have already been exceeded in the most polluted areas of south-west Norway. [source]


    Modified method for external attachment of transmitters to birds using two subcutaneous anchors

    JOURNAL OF FIELD ORNITHOLOGY, Issue 3 2008
    Tyler L. Lewis
    ABSTRACT Of the transmitter attachment techniques for birds, the subcutaneous anchor provides a secure attachment that yields relatively few secondary effects. However, the use of subcutaneous anchors has been limited by transmitter size and retention time. Using a modified method of attachment that utilized two subcutaneous anchors, we deployed 69 GPS transmitters, plus 13 VHF transmitters that were similar in size and weight to GPS models, on Pacific Black Brant (Branta bernicla nigricans). Prior to our study, only harnesses were used for attaching GPS transmitters on birds, mainly because GPS transmitters are too large for other external attachment techniques and implantation in the body cavity attenuates the GPS signal. Thus, to increase the size capacity of anchor attachment and to avoid the well-documented negative effects of harnesses on behavior and survival, we added a second anchor at the transmitter's posterior end. The double-anchor attachment technique was quickly and easily accomplished in the field, requiring bird handling times of <10 min. Incidental recoveries of tagged Brant indicate a high degree of transmitter retention. Five recaptured birds (4,6 weeks after deployment) and eight killed by hunters (3,6 mo after deployment) retained their GPS transmitters. For studies involving the use of relatively large transmitters, the double-anchor method appears to provide a viable alternative for external attachment. SINOPSIS Entre las técnicas para montar radiotransmisores a aves, el anclaje subcutáneo provee una forma segura de montaje que presenta muy pocos efectos secundarios. Sin embargo, la utilidad del anclaje subcutáneo ha sido limitada por el tamaño del transmisor y el tiempo de retención en el ave. Utilizando un método modificado que utiliza dos puntos subcutáneos de anclaje, desarrollamos 69 transmisores GPS y 13 transmisores VHF que replicaban el tamaño y peso de modelos GPS, y que fueron montados en individuos del ganso, Branta bernicla nigricans. Previo a este estudio, solo se habían utilizado arneses para colocar radiotransmisores en los gansos. Esto fue así porque los tipo GPS son demasiado grandes para ser colocados de otra manera y cuando se implantan en la cavidad celómica, queda atenuada la señal del transmisor. Por tal razon, y para incrementar la capacidad de anclaje del transmisor y evitar el impacto negativo documentado en los arneses (en conducta y sobrevivencia), añadimos un segundo punto de anclaje en la parte posterior del transmisor. La técnica desarrollada fue fácil de aplicar en el campo y se hizo de forma rápida (<10 minutos). Recobros incidentales de gansos (4 recapturas, 4,6 semanas después) y ocho individuos cazados (3,6 meses después) indicaron un 100% de retención de los transmisores. Para estudios que conlleven transmisores de gran tamaño, el método de doble anclaje parece proveer una alternativa adecuada. [source]


    Types of the Italian freshwater goby Padogobius nigricans (Canestrini, 1867)

    JOURNAL OF FISH BIOLOGY, Issue 6 2001
    A. Nocita
    The location of type material of the Italian freshwater goby Gobius fluviatilis var. nigricans Canestrini, 1867 was previously unknown. However, syntypes of this taxon have been identified now in the Museo Universitario di Storia Naturale e della Strumentazione Scientifica, Modena, Italy. Also this material is the type series of Gobius avernensis, described by Canestrini in 1868. Vestigial predorsal squamation in Padogobius nigricans is noted. [source]


    Rapid PCR-RFLP Method for the Identification of 5 Billfish Species

    JOURNAL OF FOOD SCIENCE, Issue 4 2005
    Hung-Sheng Hsieh
    ABSTRACT: A rapid and reliable polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was developed to identify billfish species Xiphias gladius (swordfish), Makaira nigricans (blue marlin), Makaira indica (black marlin), Istiophorus platypterus (sailfish), and Tetrapturus audax (striped marlin). After DNA extraction and amplifying, the 348-bp PCR products from gene encoding of cytochrome b were subjected to restriction enzyme analysis. No single enzyme tested was able to distinguish the 5 species at the same time, but the combination of results obtained from the digests of Bsa JI and Cac 81 could be used to differentiate the 5 billfish species. This sensitive, rapid, and valid method can be used to detect fraudulent substitutes. [source]


    Morphological characterization of the testicular cells and seminiferous epithelium cycle in six species of Neotropical bats

    JOURNAL OF MORPHOLOGY, Issue 8 2009
    Mateus R. Beguelini
    Abstract We know little about the process of spermatogenesis in bats, a great and diverse clade of mammals that presents different reproductive strategies. In the present study, spermatogenesis in six species of Neotropical bats was investigated by light microscopy. On the basis of chromatin condensation, nuclear morphology, relative position to the basal membrane and formation of the flagellum, three types of spermatogonia were recognized: dark type A (Ad), pale type A (Ap), and type B; the development of spermatids was divided into seven steps. With the exception of Myotis nigricans, the seminiferous epithelium cycle of the other five species studied was similar to those of other mammals, showing gradual stages by the tubular morphology method. Asynchrony was observed in the seminiferous epithelium cycle of M. nigricans, shown by overlapping stages and undefined cycles. The frequencies found in the three phases of the cycle were variable with the greatest frequency occurring in the postmeiotic phase (>50%) and the least in the meiotic phase (<10%). The similarities observed in the five species of Phyllostomidae appeared to be related to their phylogenetic relationship and shorter divergence times, whereas the differences in M. nigricans appeared to be related to its greater phylogenetic distance because the Vespertilionidae family diverged earlier. J. Morphol., 2009. © 2009 Wiley-Liss, Inc. [source]


    Confluent and reticulated papillomatosis and acanthosis nigricans in an obese girl: two distinct pathologies with a common pathogenetic pathway or a unique entity dependent on insulin resistance?

    JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 4 2006
    SP Cannavò
    [source]


    Acanthosis nigricans: A new cutaneous sign in severe atopic dermatitis and Down syndrome

    JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 4 2001
    MA Muñoz-Pérez
    Abstract Acanthosis nigricans (AN) occurs associated with many different systemic diseases, such as endocrine disorders and internal malignant neoplasms. To our knowledge, the association of AN with severe atopic dermatitis (AD) or Down syndrome has not been described before. This 82-month retrospective study included 1038 patients: AN was present in 4.9% of atopic patients and 50.9% of subjects with Down syndrome. AN was more frequent in patients with severe AD and in 100% of cases of hand dermatitis and juvenile plantar dermatosis, located on the interphalangeal and metacarpophalangeal joints, whereas in Down syndrome other flexures were also affected. The pathogenesis of AN in AD is unknown, but in Down syndrome it seems to be related to obesity. Possible insulin resistance underlyng the pathogenesis of AN in these patients is still unknown. [source]


    Florid cutaneous and mucosal papillomatosis with acanthosis nigricans revealing a primary lung cancer

    JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2000
    Ugo Bottoni
    Abstract This is the report of an 80-year-old patient with diffuse brownish hyperpigmentation and velvety thickening of the skin with onset 1 year before. Warty lesions on his limbs were present as well as papillomatous and verrucous lesions on his lips, mouth and eyelid conjunctivae with hyperkeratosis of the nipples. Biopsies, performed at different sites, showed histological pictures consistent with a diagnosis of acanthosis nigricans (AN) with florid cutaneous and mucosal papillomatosis. This type of AN is frequently associated with internal malignancy. In our patient serum levels of tissue polypeptide antigen, carcinoembryonic antigen, cytokeratin fragment and squamous cell carcinoma antigen were high and chest computed tomography scan indicated a large tumour infiltrating the right lung and extending to the mediastinum. Cytological examination of bronchial drainage revealed the presence of neoplastic cells, non-small cell type carcinoma. The most frequent cancer associated with malignant AN is gastric adenocarcinoma. Lung tumour has rarely been reported with AN. Malignant AN is sometimes associated with other cutaneous and mucosal warty lesions, as in our patient. These various skin and mucosal lesions are the expression of a systemic epithelial disorder and may help clinicians to suspect a malignant form of AN. [source]


    Distribution of the genus Hypoplectrus (Teleostei: Serranidae) in the Greater Caribbean Region: support for a color-based speciation

    MARINE ECOLOGY, Issue 2 2010
    Alfonso Aguilar-Perera
    Abstract The reef-associated fish genus Hypoplectrus (Serranidae), endemic to the western Atlantic Ocean, represents an ideal model to study speciation within a potentially highly dispersive (marine) ecosystem, because it consists of a complex of at least 10 morphs differentiated primarily by coloration. Although several recent studies on genetics, diet, and fertilization reveal little to no difference between the Hypoplectrus color morphs, there is still not a full understanding of what keeps these morphs distinct or drives their variation. Ecological information is needed alongside the genetic information to better understand this variation. Based on presence/absence records from scientific literature and direct observations in coral reefs, this work examined the distribution of the genus Hypoplectrus in the Greater Caribbean region. Some color morphs occurred simultaneously at given locations, but others showed geographic restrictions. Using cluster and nMDS analyses, we found three major groupings according to distribution: (i) widespread (Hypoplectrus puella, Hypoplectrus unicolor, and Hypoplectrus nigricans), (ii) less widespread (Hypoplectrus indigo, Hypoplectrus gummigutta, Hypoplectrus chlorurus, Hypoplectrus aberrans, and Hypoplectrus guttavarius), and (iii) geographically confined or segregated (Hypoplectrus gemma, Hypoplectrus providencianus). Geographic sections selected for the Greater Caribbean (eastern, western and northern) were dominated by at least three widely distributed Hypoplectrus morphs. New geographic records of some color morphs were documented and compared to previous established distribution ranges in the Greater Caribbean. [source]


    Rare case of Alstrom syndrome without obesity and with short stature, diagnosed in adulthood (Case Report)

    NEPHROLOGY, Issue 2 2006
    EYUP KOÇ
    SUMMARY: Alstrom syndrome is a rare autosomal recessive disorder characterized by retinal degeneration, sensorineural hearing loss, obesity, type 2 diabetes mellitus and chronic nephropathy. It may be associated with acanthosis nigricans, hypergonadotropic hypogonadism, hepatic dysfunction, hepatic steatosis, hyperlipidaemia, dilated cardiomyopathy and short stature. We report a patient with Alstrom syndrome who had hypergonadotropic hypogonadism, hepatic dysfunction, hepatic steatosis and short stature with normal body weight, all of which are seen infrequently with this syndrome. [source]


    Perioperative care of a patient with Beare,Stevenson syndrome

    PEDIATRIC ANESTHESIA, Issue 12 2005
    SARA UPMEYER DO
    Summary Beare,Stevenson syndrome is a craniofacial syndrome consisting of a specific pattern of craniosynostosis resulting in a cloverleaf skull deformity and hydrocephalus, down-slanting palpebral fissures, proptosis, hypertelorism, strabismus, dysmorphic ears, choanal atresia, cleft palate, cutis gyratum, acanthosis nigricans, and abnormal genitalia. Its primary cause has been identified as a single amino acid substitution in fibroblast growth factor receptor 2. Of primary importance to the anesthesiologist are issues related to airway management resulting from midface hypoplasia, choanal atresia, and airway abnormalities (tracheal stenosis). Additional issues affecting airway management include associated cervical spine and foramen magnum abnormalities. The authors present their experience caring for a patient with Beare,Stevenson syndrome and discuss the anesthesia care of these patients. [source]


    Acanthosis Nigricans: A Common Finding in Overweight Youth

    PEDIATRIC DERMATOLOGY, Issue 6 2007
    Wendy J. Brickman M.D.
    Youth (7,17 years) at nine pediatric practices completed surveys on demographics and family history of diabetes and had weight and height measured. Acanthosis nigricans was scored and digital photography of the neck performed. A total of 618 youth were included in the analysis: mean age 11.5 years; 51% female; 61% African American, 27% Hispanic, 12% Caucasian, and 32% with body mass index ,95th percentile. Acanthosis was found in 19%, 23%, and 4% of the African American, Hispanic, and Caucasian youth, respectively, and in 62% of youth with a body mass index ,98th percentile. Using multiple logistic regression, we found increasing body mass index z -score, presence of maternal gestational diabetes, female gender, and not being Caucasian each were independently associated with acanthosis nigricans. Acanthosis was common among overweight youth and was associated with risk factors for glucose homeostasis abnormalities. Acanthosis nigricans can be a trigger to counsel families on its causes and consequences; and thus motivate them to make healthy lifestyle changes that can decrease the risk of developing cardiovascular disease or diabetes. [source]


    Thyroid autoimmunity in children with features of both type 1 and type 2 diabetes

    PEDIATRIC DIABETES, Issue 4pt1 2008
    Ingrid M Libman
    Aim/hypothesis:, To assess the prevalence of autoimmune thyroid disease (ATD) in insulin-treated youth with clinical features of type 2 diabetes mellitus (T2DM). Methods:, We evaluated prevalence of thyroid peroxidase (TPO) and thyroglobulin (TGA) antibodies at onset of insulin-treated diabetes and follow-up in 183 White and Black children. Of these, 136 had a body mass index (BMI) <85th percentile with 122 (89%) positive for ,-cell autoimmunity [type 1 diabetes mellitus (T1DM)/group I], 25 were overweight (BMI ,85thpercentile) with or without acanthosis nigricans with ,-cell autoimmunity [,double' diabetes (DD)/group II], and 22 were overweight with no conventional ,-cell autoantibodies (group III). Results:, The prevalence of TPO and/or TGA was 39 and 29% (p = 0.19) in White and Black children and 39, 32, and 0% (p = 0.007) in groups I, II, and III, respectively. After a median follow-up of 60 months, 3.7, 4.3, and 0% developed hypothyroidism (increased thyroid-stimulating hormone with or without decreased free T4) in groups I, II, and III, respectively (p = 0.6). In subjects with TPO and/or TGA, hypothyroidism developed in 10 and 14% of groups I and II, respectively (p = 0.7). No child without thyroid antibodies developed hypothyroidism. Conclusions:, In patients with clinical features of T2DM who have evidence of ,-cell autoimmunity (DD), the frequency of thyroid antibodies and ATD is similar to that in classical T1DM. This suggests that TIDM comorbidities may be common in clinical T2DM patients who have ,-cell autoimmunity. Despite their obesity, youth with insulin-requiring diabetes should be screened for thyroid and possibly other T1DM-associated autoimmune diseases. [source]


    Acanthosis nigricans is a reliable cutaneous marker of insulin resistance in obese Japanese children

    PEDIATRICS INTERNATIONAL, Issue 6 2003
    Hajime Yamazaki
    AbstractBackground:,Acanthosis nigricans (AN) is a skin condition characterized by darkening and thickening of skin with formation of irregular folds, usually limited to a few specific areas of the body. Recently, AN has been reported to be linked to hyperinsulinemia and obesity. The aim of the present study was to determine whether or not the presence of AN in obese Japanese children is a reliable cutaneous marker. Methods:,The authors analyzed the clinical characteristics of 439 obese Japanese children (260 boys, 179 girls; mean age 10.1 years; mean percentage overweight 51.9%), who had visited Tsuruoka City Shonai Hospital in 1990,2000. Eighty-two of the 439 children were examined using an oral glucose tolerance test (OGTT). Of these children, the authors retrospectively studied 16 subjects: eight with AN and eight without AN (age range: 10.8,13.9 years; percentage overweight range: 54.3,97.0%). They were age and percentage obesity-matched males with normal glucose tolerance during OGTT. Females with normal glucose tolerance during OGTT were excluded from the 16 subjects because the number was too small and children with impaired glucose tolerance or type 2 diabetes during OGTT were also excluded because of glucose toxicity. Eighty-two children including the 16 subjects were analyzed at their first visit for the presence or absence of AN on the posterior of the neck, and for characteristics including age, birthweight, body height, bodyweight, percentage overweight, blood pressure, liver function markers serum lipid concentrations, fasting plasma glucose concentrations and insulin concentrations shown by the results of OGTT. Results:,(1) Children with AN showed significantly more glucose intolerance including impaired glucose tolerance and type 2 diabetes compared with those children without AN, and fasting plasma insulin concentrations were most significantly correlated with the presence of AN. (2) Insulin resistance based on fasting plasma insulin concentrations was seen in significantly more children with AN than in children without AN, even in age and percentage obesity-matched subjects with normal glucose tolerance during OGTT. Conclusions:, Acanthosis nigricans could be a reliable cutaneous marker of insulin resistance in obese Japanese children. [source]


    Type 2 diabetes in adolescence , unearthed at the time of registration with the general practitioner (GP)

    PRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 8 2000
    GYT Ng
    Abstract Type 2 diabetes, or non-insulin-dependent diabetes mellitus (NIDDM), is often considered to be a diagnosis of adulthood. We present a 13 year old boy who was noted to have glycosuria on routine general practitioner (GP) urine testing. Clinical examination upon referral showed massive obesity, hypertension and prominent acanthosis nigricans, and investigations confirmed hyperinsulinaemia and hyperglycaemia. Metformin and a programme of weight reduction comprise the management of this young adolescent with type 2 diabetes. Such early diagnosis should permit the institution of appropriate management to avoid the early emergence of the complications of type 2 diabetes. Copyright © 2000 John Wiley & Sons, Ltd. [source]


    Nevoid acanthosis nigricans localized to the umbilicus

    THE JOURNAL OF DERMATOLOGY, Issue 6 2006
    Sung Kwon KIM
    No abstract is available for this article. [source]