Alterations in dihydropyridine receptors in dystrophin-deficient cardiac muscle

The deficiency of dystrophin, a critical membrane stabilizing protein, in the mdx mouse causes an elevation in intracellular calcium in myocytes. One mechanism that could elicit increases in intracellular calcium is enhanced influx via the L-type calcium channels. This study investigated the effects of the dihydropyridines BAY K 8644 and nifedipine and alterations in dihydropyridine receptors in dystrophin-deficient mdx hearts. A lower force of contraction and a reduced potency of extracellular calcium (P < 0.05) were evident in mdx left atria. The dihydropyridine agonist BAY K 8644 and antagonist nifedipine had 2.7- and 1.9-fold lower potencies in contracting left atria (P < 0.05). This corresponded with a 2.0-fold reduction in dihydropyridine receptor affinity evident from radioligand binding studies of mdx ventricular homogenates (P < 0.05). Increased ventricular dihydropyridine receptor protein was evident from both radioligand binding studies and Western blot analysis and was accompanied by increased mRNA levels (P < 0.05). Patch-clamp studies in isolated ventricular myocytes showed no change in L-type calcium current density but revealed delayed channel inactivation (P < 0.05). This study indicates that a deficiency of dystrophin leads to changes in dihydropyridine receptors and L-type calcium channel properties that may contribute to enhanced calcium influx. Increased influx is a potential mechanism for the calcium overload observed in dystrophin-deficient cardiac muscle.

Biogenesis of caveolae: a structural model for caveolin-induced domain formation

Caveolae are striking morphological features of the plasma membrane of mammalian cells. Caveolins, the major proteins of caveolae, play a crucial role in the formation of these invaginations of the plasma membrane; however, the precise mechanisms involved are only just starting to be unravelled. Recent studies suggest that caveolae are stable structures first generated in the Golgi complex. Their formation and exit from the Golgi complex is associated with caveolin oligomerisation, acquisition of detergent insolubility, and association with cholesterol. Modelling of caveolin-membrane interactions together with in vitro studies of caveolin peptides are providing new insights into how caveolin-lipid interactions could generate the unique architecture of the caveolar domain.

Non-coding RNAs in the nervous system

Increasing evidence suggests that the development and function of the nervous system is heavily dependent on RNA editing and the intricate spatiotemporal expression of a wide repertoire of non-coding RNAs, including micro RNAs, small nucleolar RNAs and longer non-coding RNAs. Non-coding RNAs may provide the key to understanding the multi-tiered links between neural development, nervous system function, and neurological diseases.

Urine D-arabinitol/L-arabinitol ratio in diagnosing Candida infection in patients with haematological malignancy

Adult patients with hematologic malignancies along with HIV infected patients were prospectively studied to determine the performance of urine D-arabinitol/L-arabinitol (DA/LA) ratio in diagnosing invasive candidiasis. Ten evaluable febrile neutropenic patients had proven invasive candidiasis and elevated DA/LA ratios were found in 5. Invasive candidiasis with normal DA/LA ratios was most frequently due to Candida krusei infection. This Candida species is a non-producer of arabinitol. Only 4 of 81 febrile neutropenic patients given either antifungal prophylaxis or empiric antifungal treatment had elevated DA/LA ratios. Only 1 of 15 HIV positive patients with either oropharyngeal or esophageal candidiasis had elevated DA/LA ratios. Widespread use of fluconazole prophylaxis in bone marrow transplantation patients at the study hospital has led to an increased prevalence of C. krusei infection. This is the likely reason for the low sensitivity of the test in proven and suspected invasive Candida infections reported here. (C) 2002 Elsevier Science Inc. All rights reserved.

An overview of eye-related photophobias

This chapter provides an overview of the various eye-related causes of photophobia and the likely mechanisms responsible. Photophobia is the experience of discomfort affecting the eyes as a result of exposure to light. It has a variety of causes, including the result of eye or brain disease, or it can be a side effect of various drugs or laser surgery. Photophobia can also be a symptom of a more serious disorder such as meningitis and therefore, requires appropriate investigation, diagnosis, and treatment. Trauma or disease affecting several structures of the eye are a common cause of photophobia and can be associated with: (1) the ocular adnexia, such as blepharitis and blepharospasm, (2) the cornea, including abrasion, ulcerative keratitis, and corneal dystrophy, (3) problems in eye development, such as aniridia, buphthalmos, coloboma, and aphakia, (4) various eye inflammations, including uveitis, and (5) retinal disorders, such as achromatopsia, retinal detachment, and retinal dystrophy. There may be two main explanations for photophobia associated with these conditions: (1) direct stimulation of the trigeminal nerve due to damage, disease, or excessive light entering the eye and (2) overstimulation of the retina including a specific population of light-sensitive ganglion cells.

Eye-related photophobia

This article provides an overview of the various eye-related causes of photophobia and the likely mechanisms responsible. Photophobia is an experience of discomfort affecting the eyes due to exposure to light. It has a variety of causes including the result of eye or brain disease, or it can be a side effect of various drugs or laser surgery. Photophobia can also be a symptom of a more serious disorder such as meningitis and therefore, requires appropriate investigation, diagnosis, and treatment. Trauma or disease affecting several structures of the eye are a common cause of photophobia and can be associated with: (1) the ocular adnexia, such as blepharitis and blepharospasm, (2) the cornea, including abrasion, ulcerative keratitis, and corneal dystrophy, (3) problems in eye development, such as aniridia, buphthalmos, coloboma, and aphakia, (4) various eye inflammations, including uveitis, and (5) retinal disorders, such as achromatopsia, retinal detachment, and retinal dystrophy. There may be two main explanations for eye-related photophobia: (1) direct stimulation of the trigeminal nerve due to damage, disease, or excessive light entering the eye and (2) overstimulation of the retina including a specific population of light-sensitive ganglion cells.

Avaliação comparativa da eficácia dos meios de diagnóstico das vulvovaginites: implantação de tecnologia no ensino prático da ginecologia

Inaccurate diagnosis of vulvovaginitis generates inadequate treatments that cause damages women's health. Objective: evaluate the effectiveness of methods when diagnosing vulvovaginitis. Method: a cross-sectional study was performed with 200 women who complained about vaginal discharge. Vaginal smear was collected for microbiological tests, considering the gram stain method as gold standard. The efficacy of the available methods for diagnosis of vaginal discharge was assessed (sensitivity, specificity, positive predictive value and negative predictive value). Data were inserted to Graphpad Prism 6, for statistical analysis. Results: the following results were obtained: wet mount for vaginal candidiasis: sensitivity = 31%; specificity = 97%; positive predictive value (PPV) = 54%; negative predictive value (NPV) =93%; accuracy = 91%. Wet mount for bacterial vaginosis: sensitivity = 80%; specificity =95%; positive predictive value (PPV) = 80%; negative predictive value (NPV) = 95%; accuracy = 92%. Syndromic approach for bacterial vaginosis: sensitivity = 95%; specificity=43%; positive predictive value (PPV) =30%; negative predictive value (NPV) = 97%; accuracy = 54%. Syndromic approach for vaginal candidiasis: sensitivity = 75%; specificity =91%; positive predictive value (PPV) = 26%; negative predictive value (NPV) = 98%; accuracy = 90%. Pap smear for vaginal candidiasis: sensitivity = 68%, specificity = 98%; positive predictive value (PPV) = 86%; negative predictive value (NPV) =96%; accuracy = 96%. Pap smear for bacterial vaginosis: sensitivity = 75%; specificity = 100%; positive predictive value (PPV) = 100%; negative predictive value (NPV) =94%; accuracy = 95%. There was only one case of vaginal trichomoniasis reported – diagnosed by oncological cytology and wet mount – confirmed by Gram. The syndromic approach diagnosed it as bacterial vaginosis. From the data generated and with support on world literature, the Maternidade Escola Januário Cicco’s vulvovaginitis protocol was constructed. Conclusion: Pap smear and wet mount showed respectively low and very low sensitivity for vaginal candidiasis. Syndromic approach presented very low specificity and accuracy for bacterial vaginosis, which implies a large number of patients who are diagnosed or treated incorrectly.

Efeito do ácido ascórbico sobre a espermatogênese de camundongos com distrofia muscular de Duchenne

The objective was to evaluate spermatogenesis alterations caused by DMD and the effect of the treatment using ascorbic acid in preventing those injuries. Twenty four mice were used, 12 from the C57BL/10 lineage (non-dystrophic) and 12 from the C57BL/10Mdx (dystrophic). The sample was divided in six groups containing 4 animals each, as: C30 = 30 days control; D30 = Dystrophic with 30 days; C60 = 60 days control; D60 = Distrophic with 60 days; CS60 = 60 days control supplemented with ascorbic acid and DS60 = Dystrophic with 60 days supplemented with ascorbic acid. The ascorbic acid supplementation was given in the water, 0,005 mg/day. After euthanasia, the testicles (right and left) were collected, weighted and cross sectioned. The material was fixed in the Karnovsky solution for 24 hours, included in resin for histological studies (morphological and morphometric analyzes) submitted to ultrastructural analysis and immunohistochemistry for caspase-3. There was a significant increase in the tunica propria percentage in D30 compared to C30 and D60. The ultrastructural analysis showed mitochondrial apoptosis evidence of Sertoli cells that can reduce sperm efficiency in CS60 and DS60. A higher volume density of apoptotic cells postivas to Caspase-3 in C30 and D30 versus DS60 compared to CS60. There was severe hypertrophy of the Leydig cells between D30 and D60. However, with supplementation was observed reversal of this change in DS60. The ultrastructure of Leydig cells to early presence of lipid vesicles was observed in the group pre-pubertal dystrophic (D30). Thus, the DMD affect the organization of the seminiferous tubules and intertubule, however, the ascorbic acid supplementation used for the treatment of DMD has been just enough to reduce the hypertrophy of the Leydig cells.

Capacidade de adesão e formação de biofilme de Candida ssp. isoladas da cavidade oral de pacientes transplantados renais na presença do extrato de Eugenia uniflora

Candidiasis is a major oral manifestation in kidney transplant patients. Candida spp. possess essential virulence factors which contribute for the infectious process, including the ability to adhere to epithelial cells and biofilm formation. The extract obtained from the leaves of Eugenia uniflora [acetone: water (7:3, v/v)] has demonstrated antifungal activity against Candida spp. This study evaluated the influence of the extract of E. uniflora in adhesion to human buccal epithelial cells (HBEC) and biofilm formation of 42 strains of Candida spp. isolated from the oral cavity of kidney transplant patients. Candida spp. strains belonging to a culture collection were reactivated and phenotypically re-identified by classical and molecular methods (genotyping ABC and RAPD), when necessary, to complete the identification to the species level. For the virulence tests evaluated in vitro, yeasts were grown in the presence and absence of 1000 g/mL of the extract. A ratio of 10: 1 (Candida spp. cells x HBECs) was incubated for 1 hour at 37 ° C, 200 rpm, fixed with 10% formalin and the number of Candida cells adhered to 150 HBEC determined by optical microscope. Biofilms were formed on polystyrene microplates in the presence or absence of the extract. The quantification was performed with crystal violet staining at 570 nm. All isolates were viable and exhibited phenotypic characteristics suggestive of each species identified. Two strains presumptively identified as Candida dubliniensis belonged to this species as determined with genotyping ABC, while strains identified as belonging to the Candida parapsilosis species complex were differentiated by RAPD genotyping. Candida albicans was found to be the most adherent species to the buccal epithelia, while C. tropicalis showed remarkable biofilm formation.We could detect that the extract of E. uniflora was able to reduce adhesion to HBEC for both Candida albicans and non-Candida albicans Candida species. On the other hand, only 16 Candida spp. strains (36 %) showed reduced biofilm formation. However, two highly biofilm producer strains of C. tropicalis had an expressive reduction in biofilm formation. This study reinforces the idea that besides growth inhibition, E. uniflora may interfere with the expression of some virulence factors of Candida spp., and may be possibly applied in the future as a novel antifungal agent.

Desarrollo de nuevas formulaciones tópicas de anfotericina B para el tratamiento de micosis

Las infecciones por hongos se han convertido en un tema de gran preocupación en todo el mundo, se estima que más de 40 millones de personas sufren infecciones por hongos, tanto en países desarrollados como en países en vías de desarrollo (Güngör, et al., 2013). Las micosis superficiales se encuentran entre las formas más frecuentes de infecciones en los humanos. Se estima que afectan un 20-25 % de la población mundial y su incidencia está constantemente en aumento (Vena, et al., 2012) (Havlickova, et al., 2008) (Das, et al., 2007). Actualmente, este tipo de infecciones son un frecuente motivo de consulta para el médico de familia (Hernández, et al., 2014) y el dermatólogo. Lo cual nos obliga a permanecer constantemente actualizados La candidiasis es la micosis emergente con mayor efecto en el ser humano debido a su frecuencia y a la gravedad de sus complicaciones (López-Martínez, R., 2010). La candidiasis superficial es una de las formas clínicas más comunes. Es característicamente crónica y recurrente, y, a veces, indica el comienzo de las formas graves de esta micosis (Pappas, et al., 2009). Las levaduras del género Candida son microorganismos pertenecientes a la microbiota normal de individuos sanos, principalmente en la mucosa oral, el tracto gastrointestinal y el tracto genitourinario femenino (Shao, et al., 2007). Sin embargo, estos hongos son responsables de diferentes manifestaciones clínicas, especialmente en pacientes inmunocomprometidos, que van desde infecciones de la piel y mucosas a infecciones sistémicas (Sardi, et al., 2013). Su importancia viene de la alta frecuencia con que colonizan e infectan el huésped humano (De Bernardis, et al., 2004), siendo el cuarto patógeno más común asociado con los casos de infección nosocomial (Wisplinghoff, et al., 2004)...

Systemic restoration of UBA1 ameliorates disease in spinal muscular atrophy

Blood biochemistry analysis and serum analysis were performed by the Easter Bush Pathology Department, University of Edinburgh. Animal husbandry was performed by Centre for Integrative Physiology bio-research restructure technical staff, University of Edinburgh. Assistance with intravenous injections was provided by Ian Coldicott (University of Sheffield) and Hannah Shorrock (University of Edinburgh). Human blood cDNA was a gift to GH from Kathy Evans, University of Edinburgh. Imaging was performed at the IMPACT imaging facility, University of Edinburgh, with technical assistance from Anisha Kubasik-Thayil. The authors would also like to thank Lyndsay Murray for technical discussions relating to qRT-PCR analysis. This work was supported by funding from the SMA Trust and the Anatomical Society (via grants to THG); the Euan MacDonald Centre for Motor Neurone Disease Research (via grants to THG and SHP); the Wellcome Trust (via grants to EJNG and THG); Muscular Dystrophy UK (via grants to THG and CGB); a Elphinstone Scholarship from the University of Aberdeen (to SHP); and The French Muscular Dystrophy Association (via grants to CM and JC).

Vascular defects and spinal cord hypoxia in spinal muscular atrophy

© 2015 American Neurological Association. Funded by The Euan MacDonald Center for Motor Neurone Disease Research The SMA Trust Muscular Dystrophy UK The SMA Trust The SMA Trust Motor Neurone Disease Association National Institute for Health Research Great Ormond Street Hospital Biomedical Research Center Medical Research Council Great Ormond Street Hospital Charity

Type 1 ryanodine receptor interactions

Excitation-contraction coupling is an essential part of skeletal muscle contraction. It encompasses the sensing of depolarisation of the plasma membrane coupled with the release of Ca2+ from intracellular stores. The channel responsible for this release is called the Ryanodine receptor (RyR), and forms a hub of interacting proteins which work in concert to regulate the release of Ca2+ through this channel. The aim of this work was to characterise possible novel interactions with a proline-rich region of the RyR1, to characterise a monoclonal antibody (mAb VF1c) raised against a junctional sarcoplasmic reticulum protein postulated to interact with RyR1, and to characterise the protein recognised by this antibody in models of skeletal muscle disease such as Duchenne Muscular dystrophy (DMD) and sarcopenia. These experiments were performed using cell culture, protein purification via immunoprecipitation, affinity purification, low pressure chromatography and western blotting techniques. It was found that the RyR1 complex isolated from rat skeletal muscle co-purifies with the Growth factor receptor bound protein 2 (GRB2), very possibly via an interaction between the proline rich region of RyR1 and one of the SH3 domains located on the GRB2 protein. It was also found that Pleiotrophin and Phospholipase Cγ1, suggested interactors of the proline rich region of RyR1, did not co-purify with the RyR1 complex. Characterisation of mAb VF1c determined that this monoclonal antibody interacts with junctophilin 1, and binds to this protein between the region of 369-460, as determined by western blotting of JPH1 fragments expressed in yeast. It was also found that JPH1 and JPH2 are differentially regulated in different muscles of rabbit, where the highest amount of both proteins was found in the extensor digitorum longus (EDL) muscle. JPH1 and 2 levels were also examined in three rodent models of disease: the mdx mouse (a model of DMD), chronic intermittent hypoxia (CIH)-treated rat, and aged and adult mice, a model of sarcopenia. In the EDL and soleus muscle of CIH treated rats, no difference in either JPH1 or JPH2 abundance was detected in either muscle. An examination of JPH1 and 2 expression in mdx and wild type controls diaphragm, vastus lateralis, soleus and gastrocnemius muscle found no major differences in JPH1 abundance, while JPH2 was decreased in mdx gastrocnemius compared to wild type. In a mouse model of sarcopenia, JPH1 abundance was found to be increased in aged soleus but not in aged quadriceps, while in exercised quadriceps, JPH2 abundance was decreased compared to unexercised controls. Taken together, these results have implications for the regulation of RyR1 and JPH1 and 2 in skeletal muscle in both physiological and pathological states, and provide a newly characterised antibody to expand the field of JPH1 research.

Habitudes alimentaires et apports nutritionnels chez les personnes présentant une dystrophie myotonique de type 1

L’objectif de cette étude était de décrire les habitudes alimentaires et les apports nutritionnels des patients atteints de dystrophie myotonique de type 1 (DM1). Au total, 32 femmes et 20 hommes souffrant de DM1 et suivis à la Clinique des maladies neuromusculaires de Jonquière, ont complété un journal alimentaire de 3 jours non consécutifs (2 jours de semaine et 1 jour de fin de semaine). Parmi ces patients, 13,5 % étaient en sous-poids alors que 51,9 % présentaient de l’embonpoint ou de l’obésité. Les apports moyens en lipides et en glucides ne respectaient pas l’étendue des valeurs acceptables pour ces macronutriments. Les apports moyens étaient également insuffisants pour la majorité des micronutriments. Finalement, la consommation d’aliments des quatre groupes du Guide alimentaire canadien était inférieure aux recommandations. Les résultats démontrent qu’une proportion importante des patients avec DM1 présente une alimentation inadéquate.