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31.

Background

Hemifacial atrophy (Parry-Romberg syndrome) is a relatively rare disease. The etiology of the disease is not clear. Some authors postulate its relation with limited scleroderma linearis. Linear scleroderma "en coup de sabre" is characterized by clinical presence of most commonly one-sided linear syndrome. In a number of patients, neurological affection is the medium of the disease. The treatment of both scleroderma varieties is similar to the treatment of limited systemic sclerosis.

Case presentation

We present two cases of a disease: a case of a 49-year-old woman with a typical image of hemifacial atrophy, without any changes of the nervous system and a case of a 33-year-old patient with an "en coup de sabre" scleroderma and with CNS tumor.

Conclusion

We described typical cases of a rare diseases, hemifacial atrophy and "en coup de sabre" scleroderma. In the patient diagnosed with Parry-Romberg syndrome, with Borrelia burgdoferi infection and with minor neurological symptoms, despite a four-year case history, there was a lack of proper diagnosis and treatment. In the second patient only skin changes without any neurological symptoms could be observed and only a precise neurological diagnosis revealed the presence of CNS tumor.  相似文献   
32.
Disrupted circadian rhythms are associated with obesity and metabolic alterations, but little is known about the participation of peripheral circadian clock machinery in these processes. The aim of the present study was to analyze RNA expression of clock genes in subcutaneous (SAT) and visceral (VAT) adipose tissues of male and female subjects in AM (morning) and PM (afternoon) periods, and its interactions with body mass index (BMI). Ninety-one subjects (41 ± 11 yrs of age) presenting a wide range of BMI (21.4 to 48.6 kg/m(2)) were included. SAT and VAT biopsies were obtained from patients undergoing abdominal surgeries. Clock genes expressions were evaluated by qRT-PCR. The only clock gene that showed higher expression (p 相似文献   
33.
Somatic embryogenesis induction and somatic embryo development of the solanaceous tamarillo tree were previously established and successfully used for plant regeneration from different explants and varieties. Somatic embryogenesis was induced in Murashige and Skoog medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) or picloram and high sucrose concentrations (0.25 M). The embryogenic tissues were transferred to an auxin-free medium, with reduced sucrose levels, to permit embryo development and conversion into plantlets. This two-step protocol is often impaired by an ineffective transition from the proembryogenic masses to embryo development. In this work, attempts to optimize the somatic embryogenesis system of tamarillo by improving the quality of somatic embryo and embryo conversion were carried out. The results showed that the presence of a high number of abnormal somatic embryos did not significantly inhibit plant conversion, hence indicating that shoot apical meristem development was not affected in abnormal somatic embryos. It was also shown that the manipulation of sucrose concentration in the development medium (0.11 M) and dark conditions before conversion increased the number of morphologically normal somatic embryos. The comparison between mature cotyledonary zygotic and somatic embryos showed an inefficient accumulation of storage compounds, mainly lipids, in somatic embryos. These reduced levels of lipid storage could be responsible for the abnormal patterns of embryo development found in tamarillo somatic embryos.  相似文献   
34.
Brazilian cherry (Eugenia uniflora L.) occurs in the Brazilian Atlantic Coastal Tropical Forest from the north‐eastern state of Ceara, to the southernmost state of Rio Grande do Sul. E. uniflora plays an important role in the maintenance of ‘Restinga’ ecosystems, at the interface between forest and strand vegetation. Here, we characterize the genetic diversity, its allocation within and between populations and the possible components of nuclear and cytoplasmic gene flow that determine the spatial distribution of the genetic variability. Five E. uniflora populations encompassing distinct biogeographical components were sampled: populations at extremes of latitudinal distribution, at an oceanic island and close to the major urban centre of Rio de Janeiro. AFLP markers showed that genetic variance among studied populations was moderate (Fst = 0.211) with 78.9% of variability residing within populations. The estimated seed and pollen components of gene flow among populations were approximately equal, with a ratio between 1.003 and 0.713 in function of the cpDNA marker used. The five populations present a considerable genetic structure, as assigned by both nuclear and chloroplastic DNA markers. Our data suggest the existence of different glacial refugia and a limited pollen and seed gene flow, mainly between the southern and the other regions enclosed in the Atlantic rain forest. Therefore, any strategy of conservation and management has to assure the preservation of several populations along the Atlantic coast, to maintain the majority of the intra specific level of diversity.  相似文献   
35.
36.
The South American continent is composed of several biogeographical regions harbouring the highest biodiversity on the globe, encompassing five of the world's biodiversity ‘hot spots’. Nonetheless, the patterns and processes responsible for shaping its astonishing species diversity are largely unknown. Here, we present a review of current South American phylogeographical knowledge based on published articles on this topic. An appraisal of the literature reveals emerging phylogeographical patterns in the biota of South America. The striking phylogeographical divergence observed among organism lineages in South American studies is suggestive of high levels of undocumented species diversity. The interplay between Pleistocene climatic oscillations and Pliocene/Miocene orogenic events has contributed to shaping the current diversity and distribution of modern lineages in both the tropical and temperate regions of South America. Although older divergence times were observed for a range of species, most herpetofauna underwent an intraspecific lineage split much earlier than other organisms. The geographical ranges of species associated with forest habitats were reduced mainly during glacial cycles, whereas species associated with open vegetation domains have shown variable responses to climatic oscillations. The results suggest a highly complex mosaic of phylogeographical patterns in South America. We suggest future research directions to promote a better understanding of the origin and maintenance of the South American biota.  相似文献   
37.
IntroductionPure Neural Leprosy (PNL) is a rare clinical form of leprosy in which patients do not present with the classical skin lesions but have a high burden of the disability associated with the disease. Clinical characteristics and follow up of patients in PNL are still poorly described in the literature.ObjectiveThis paper aims to describe the clinical, electrophysiological and histopathological characteristics of PNL patients, as well as their evolution after multidrug therapy (MDT).MethodsFifty-two PNL patients were selected. Clinical, nerve conduction studies (NCS), histopathological and anti-PGL-1serology were evaluated. Patients were also assessed monthly during the MDT. At the end of the MDT, all of the patients had a new neurological examination and 44 were submitted to another NCS.ResultsParesthesia was the complaint most frequently reported by patients, and in the neurological examination the most common pattern observed was impairment in sensory and motor examination and a mononeuropathy multiplex. Painful nerve enlargement, a classical symptom of leprosy neuropathy, was observed in a minority of patients and in the motor NCS axonal injuries, alone or in combination with demyelinating features, were the most commonly observed. 88% of the patients did not present any leprosy reaction during MDT. There was no statistically significant difference between the neurological examinations, nor the NCS pattern, performed before and after the MDT.DiscussionThe classical hallmarks of leprosy neuropathy are not always present in PNL making the diagnosis even more challenging. Nerve biopsy is an important tool for PNL diagnosis as it may guide therapeutic decisions. This paper highlights unique characteristics of PNL in the spectrum of leprosy in an attempt to facilitate the diagnosis and management of these patients.  相似文献   
38.
The Bacillus subtilis endospore coat protein CotA shows laccase activity. By using comparative modeling techniques, we were able to derive a model for CotA based on the known x-ray structures of zucchini ascorbate oxidase and Cuprinus cereneus laccase. This model of CotA contains all the structural features of a laccase, including the reactive surface-exposed copper center (T1) and two buried copper centers (T2 and T3). Single amino acid substitutions in the CotA T1 copper center (H497A, or M502L) did not prevent assembly of the mutant proteins into the coat and did not alter the pattern of extractable coat polypeptides. However, in contrast to a wild type strain, both mutants produced unpigmented colonies and spores unable to oxidize syringaldazine (SGZ) and 2'2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The CotA protein was purified to homogeneity from an overproducing Escherichia coli strain. The purified CotA shows an absorbance and a EPR spectra typical of blue multicopper oxidases. Optimal enzymatic activity was found at < or =pH 3.0 and at pH 7.0 for ABTS or SGZ oxidation, respectively. The apparent K(m) values for ABTS and SGZ at 37 degrees C were of 106 +/- 11 and 26 +/- 2 microm, respectively, with corresponding k(cat) values of 16.8 +/- 0.8 and 3.7 +/- 0.1 s(-1). Maximal enzyme activity was observed at 75 degrees C with ABTS as substrate. Remarkably, the coat-associated or the purified enzyme showed a half-life of inactivation at 80 degrees C of about 4 and 2 h, respectively, indicating that CotA is intrinsically highly thermostable.  相似文献   
39.
The fumarate reductases from S. frigidimarina NCIMB400 and S. oneidensis MR-1 are soluble and monomeric enzymes located in the periplasm of these bacteria. These proteins display two redox active domains, one containing four c-type hemes and another containing FAD at the catalytic site. This arrangement of single-electron redox co-factors leading to multiple-electron active sites is widespread in respiratory enzymes. To investigate the properties that allow a chain of single-electron co-factors to sustain the activity of a multi-electron catalytic site, redox titrations followed by NMR and visible spectroscopies were applied to determine the microscopic thermodynamic parameters of the hemes. The results show that the redox behaviour of these fumarate reductases is similar and dominated by a strong interaction between hemes II and III. This interaction facilitates a sequential transfer of two electrons from the heme domain to FAD via heme IV.  相似文献   
40.
Prolonged depolarization induces a slow inactivation process in some K+ channels. We have studied ionic and gating currents during long depolarizations in the mutant Shaker H4-Δ(6–46) K+ channel and in the nonconducting mutant (Shaker H4-Δ(6–46)-W434F). These channels lack the amino terminus that confers the fast (N-type) inactivation (Hoshi, T., W.N. Zagotta, and R.W. Aldrich. 1991. Neuron. 7:547–556). Channels were expressed in oocytes and currents were measured with the cut-open-oocyte and patch-clamp techniques. In both clones, the curves describing the voltage dependence of the charge movement were shifted toward more negative potentials when the holding potential was maintained at depolarized potentials. The evidences that this new voltage dependence of the charge movement in the depolarized condition is associated with the process of slow inactivation are the following: (a) the installation of both the slow inactivation of the ionic current and the inactivation of the charge in response to a sustained 1-min depolarization to 0 mV followed the same time course; and (b) the recovery from inactivation of both ionic and gating currents (induced by repolarizations to −90 mV after a 1-min inactivating pulse at 0 mV) also followed a similar time course. Although prolonged depolarizations induce inactivation of the majority of the channels, a small fraction remains non–slow inactivated. The voltage dependence of this fraction of channels remained unaltered, suggesting that their activation pathway was unmodified by prolonged depolarization. The data could be fitted to a sequential model for Shaker K+ channels (Bezanilla, F., E. Perozo, and E. Stefani. 1994. Biophys. J. 66:1011–1021), with the addition of a series of parallel nonconducting (inactivated) states that become populated during prolonged depolarization. The data suggest that prolonged depolarization modifies the conformation of the voltage sensor and that this change can be associated with the process of slow inactivation.  相似文献   
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