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1.
Prenat Diagn ; 43(3): 304-313, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36797813

RESUMEN

OBJECTIVE: Xq chromosome duplication with complex rearrangements is generally acknowledged to be associated with neurodevelopmental disorders, such as Pelizaeus-Merzbacher disease (PMD) and MECP2 duplication syndrome. For couples who required a PGT-M (pre-implantation genetic testing for monogenic disease) for these disorders, junction-specific PCR is useful to directly detect pathogenic variants. Therefore, pre-clinical workup for PGT-M requires the identification of the junction of duplicated segments in PMD and MECP2 duplication syndrome, which is generally difficult. METHODS: In this report, we used nanopore long-read sequencing targeting the X chromosome using an adaptive sampling method to identify breakpoint junctions in disease-causing triplications. RESULTS: By long-read sequencing, we successfully identified breakpoint junctions in one PMD case with PLP1 triplication and in another MECP2 triplication case in a single sequencing run. Surprisingly, the duplicated region involving MECP2 was inserted 45 Mb proximal to the original position. This inserted region was confirmed by FISH analysis. With the help of precise mapping of the pathogenic variant, we successfully re-established STR haplotyping for PGT-M and avoided any potential misinterpretation of the pathogenic allele due to recombination. CONCLUSION: Long-read sequencing with adaptive sampling in a PGT-M pre-clinical workup is a beneficial method for identifying junctions of chromosomal complex structural rearrangements.


Asunto(s)
Secuenciación de Nanoporos , Enfermedad de Pelizaeus-Merzbacher , Diagnóstico Preimplantación , Femenino , Embarazo , Humanos , Proteína Proteolipídica de la Mielina/genética , Duplicación de Gen , Pruebas Genéticas/métodos , Enfermedad de Pelizaeus-Merzbacher/genética , Cromosomas , Diagnóstico Preimplantación/métodos
2.
Adv Exp Med Biol ; 1293: 449-458, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33398832

RESUMEN

Using an optogenetic approach, we analyzed a local neuron network of the respiratory center in the medulla of a brainstem-spinal cord preparation isolated from neonatal rat. We developed a transgenic (Tg) rat line in which Phox2b-positive cells expressed archaerhodopsin-3 (Arch) or one of the step-function channelrhodopsin variants (ChRFR) under the control of Phox2b promoter-enhancer regions. Then, in en bloc preparations from 0- to 2-day-old Tg neonatal rats, we analyzed membrane potential changes of medullary respiratory-related neurons in response to photostimulation of the rostral ventral medulla. The photostimulation-induced inhibition or facilitation of the respiratory rhythm in Arch-expressing or ChRFR-expressing Tg rat preparations, respectively. Selective photoactivation of Phox2b-positive neurons expressing ChRFR in the rostral ventrolateral medulla of a neonatal rat en bloc preparation induced membrane potential changes of respiratory-related neurons that were dependent on heterogeneous properties of synaptic connections in the respiratory center. We concluded that the optogenetic approach is a powerful method of verifying a hypothetical model of local networks among respiratory-related neurons in the rostral ventrolateral medulla of neonatal rat.


Asunto(s)
Optogenética , Centro Respiratorio , Animales , Animales Recién Nacidos , Channelrhodopsins , Bulbo Raquídeo , Neuronas , Ratas , Respiración
3.
Dev Dyn ; 249(9): 1098-1116, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32243674

RESUMEN

BACKGROUND: The structure of the mouse incisor is characterized by its asymmetric accumulation of enamel matrix proteins on the labial side. The asymmetric structure originates from the patterning of the epithelial incisor placode through the interaction with dental mesenchymal cells. However, the molecular basis for the asymmetric patterning of the incisor germ is largely unknown. RESULTS: A homeobox transcription factor SIX1 was shown to be produced in the mandibular mesenchyme, and its localization patterns changed dynamically during lower incisor development. Six1-/- mice exhibited smaller lower incisor primordia than wild-type mice. Furthermore, Six1-/- mice showed enamel matrix production on both the lingual and labial sides and disturbed odontoblast maturation. In the earlier stages of development, the formation of signaling centers, the initiation knot and the enamel knot, which are essential for the morphogenesis of tooth germs, were impaired in Six1-/- embryos. Notably, Wnt signaling activity, which shows an anterior-posterior gradient, and the expression patterns of genes involved in incisor formation were altered in the mesenchyme in Six1-/- embryos. CONCLUSION: Our results indicate that Six1 is required for signaling center formation in lower incisor germs and the labial-lingual asymmetry of the lower incisors by regulating the anterior-posterior patterning of the mandibular mesenchyme.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/metabolismo , Incisivo/embriología , Odontoblastos/metabolismo , Odontogénesis , Transducción de Señal , Animales , Proteínas de Homeodominio/genética , Incisivo/citología , Ratones , Ratones Noqueados , Odontoblastos/citología , Germen Dentario/embriología
4.
Cephalalgia ; 40(11): 1177-1190, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32484063

RESUMEN

BACKGROUND: Cortical spreading depression is thought to be the underlying mechanism of migraine aura. In 2006, three relatives having the point mutation E700K in ATP1A2 exon 15 were diagnosed with familial hemiplegic migraine 2 characterized by complicated forms of aura. Here, we generated a transgenic mouse model having the human E700K mutation in the Atp1a2 orthologous gene. OBJECTIVE: To investigate the characteristics of cortical spreading depression in a mouse model with E700K mutation in the Atp1a2. METHODS: Cortical spreading depression was induced by applying stepwise increases of KCl concentration or electrical stimulation intensity to C57BL/6J-Tg(Atp1a2*E700K)9151Kwk mice (Tg, both sexes) and corresponding wild-type animals. Under urethane anesthesia, the responsiveness and threshold to cortical spreading depression were examined and the distribution of c-Fos expression, a neuronal activity marker, was immunohistochemically determined. RESULTS: Overall, Tg mice showed significantly faster propagation velocity (p < 0.01) and longer full-width-at-half-maximum (p < 0.01) than wild-type animals, representing a slower recovery from direct current potential deflection. The cortical spreading depression threshold tended to be lower in Tg, especially in females. c-Fos-positive cells were significantly enhanced in the ipsilateral somatosensory cortex, piriform cortex, amygdala and striatum (each p < 0.05 vs. contralateral side). Numbers of c-Fos positive cells were significantly higher in the ipsilateral amygdala of Tg, as compared with wild-type animals (p < 0.01). CONCLUSION: The effect of cortical spreading depression may be greater in E700K transgenic mice than that in wild-type animals, while the threshold for cortical spreading depression shows little change. Higher c-Fos expression in the amygdala may indicate alterations of the limbic system in Tg, suggesting an enhanced linkage between cortical spreading depression and amygdala connectivity in familial hemiplegic migraine 2 patients.


Asunto(s)
Depresión de Propagación Cortical/fisiología , Migraña con Aura/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Migraña con Aura/metabolismo , Migraña con Aura/fisiopatología , Mutación Puntual
5.
Pflugers Arch ; 471(11-12): 1419-1439, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31631251

RESUMEN

Paired-like homeobox gene Phox2b is predominantly expressed in pre-inspiratory neurons in the parafacial respiratory group (pFRG) in newborn rat rostral ventrolateral medulla. To analyse detailed local networks of the respiratory centre using optogenetics, the effects of selective activation of Phox2b-positive neurons in the ventral medulla on respiratory rhythm generation were examined in brainstem-spinal cord preparations isolated from transgenic newborn rats with Phox2b-positive cells expressing channelrhodopsin variant ChRFR(C167A). Photostimulation up to 43 s increased the respiratory rate > 200% of control, whereas short photostimulation (1.5 s) of the rostral pFRG reset the respiratory rhythm. At the cellular level, photostimulation depolarised Phox2b-positive pre-inspiratory, inspiratory and respiratory-modulated tonic neurons and Phox2b-negative pre-inspiratory neurons. In contrast, changes in membrane potential of Phox2b-negative inspiratory and expiratory neurons varied depending on characteristics of ongoing synaptic connections in local respiratory networks in the rostral medulla. In the presence of tetrodotoxin, photostimulation depolarised Phox2b-positive cells, but caused no significant changes in membrane potential of Phox2b-negative cells. We concluded that depolarisation of Phox2b-positive neurons was due to cell-autonomous photo-activation and summation of excitatory postsynaptic potentials, whereas membrane potential changes of Phox2b-negative neurons depended on the network configuration. Our findings shed further light on local networks among respiratory-related neurons in the rostral ventrolateral medulla and emphasise the important role of pre-inspiratory neurons in respiratory rhythm generation in the neonatal rat en bloc preparation.


Asunto(s)
Channelrhodopsins/metabolismo , Proteínas de Homeodominio/metabolismo , Bulbo Raquídeo/metabolismo , Neuronas/metabolismo , Centro Respiratorio/metabolismo , Factores de Transcripción/metabolismo , Animales , Animales Recién Nacidos , Tronco Encefálico/metabolismo , Femenino , Masculino , Potenciales de la Membrana/fisiología , Optogenética/métodos , Ratas , Respiración , Tetrodotoxina/metabolismo
6.
Microbiol Immunol ; 63(9): 359-366, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31301156

RESUMEN

Umesu phenolics were obtained from the salt extracts of Japanese apricot (Nanko-mume cultivar of Prunus mume Sieb. et Zucc.) as purified phenolics. The antiviral activities of umesu phenolics obtained were then examined against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), enveloped DNA viruses. The phenolics inhibited the multiplication of these viruses when added to the culture media of the infected cells. This inhibition occurred at phenolic concentrations at which they showed no severe cytotoxicity. One-step growth experiments showed that the eclipse period in the HSV-1 multiplication process was extended in the presence of umesu phenolics and that the addition of phenolics after the completion of viral DNA replication did not affect their multiplication. More drastic effects were observed on virucidal activities against HSV-1 and HSV-2; the infectivity decreased to 0.0001 when infected cells were incubated with 3 mg/ml phenolics at 30°C for 5 min. These results demonstrate the antiviral and virucidal activities of umesu phenolics and suggest a potential pharmacological use for these phenolics as a sanitizing or preventive medicine against superficial HSV infections.


Asunto(s)
Herpes Simple/tratamiento farmacológico , Extractos Vegetales/farmacología , Prunus armeniaca/química , Simplexvirus/efectos de los fármacos , Animales , Antivirales/farmacología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Chlorocebus aethiops , Replicación del ADN/efectos de los fármacos , Virus ADN/efectos de los fármacos , Herpesvirus Humano 1/efectos de los fármacos , Herpesvirus Humano 1/crecimiento & desarrollo , Herpesvirus Humano 2/efectos de los fármacos , Herpesvirus Humano 2/crecimiento & desarrollo , Humanos , Japón , Simplexvirus/crecimiento & desarrollo , Células Vero , Acoplamiento Viral/efectos de los fármacos , Replicación Viral/efectos de los fármacos
7.
Cephalalgia ; 38(9): 1515-1524, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29041816

RESUMEN

Background Patients with familial hemiplegic migraine type 2 (FHM2) have a mutated ATP1A2 gene (encoding Na+,K+-ATPase α2 subunit) and show prolonged migraine aura. Cortical spreading depression (CSD), which involves mass depolarization of neurons and astrocytes that propagates slowly through the gray matter, is profoundly related to aura. Methods In two types of Atp1a2-defective heterozygous mice, Atp1a2tm1Kwk (C-KO) and Atp1a2tm2Kwk (N-KO), the sensitivity and responsiveness to CSD were examined under urethane anesthesia. Results In both cases, heterozygotes exhibited a low threshold for induction of CSD, faster propagation rate, slower recovery from DC deflection, and profound suppression of the electroencephalogram, compared to wild-type mice. A high dose of KCl elicited repeated CSDs for a longer period, with a tendency for a greater frequency of CSD occurrence in heterozygotes. The difference of every endpoint was slightly greater in N-KO than C-KO. Change of regional cerebral blood flow in response to CSD showed no significant difference. Conclusion Heterozygotes of Atp1a2-defective mice simulating FHM2 demonstrated high susceptibility to CSD rather than cortical vasoreactivity, and these effects may differ depending upon the knockout strategy for the gene disruption. These results suggest that patients with FHM2 may exhibit high susceptibility to CSD, resulting in migraine.


Asunto(s)
Depresión de Propagación Cortical/fisiología , Migraña con Aura/genética , Migraña con Aura/fisiopatología , ATPasa Intercambiadora de Sodio-Potasio/genética , Animales , Modelos Animales de Enfermedad , Ratones , Ratones Noqueados
8.
Pflugers Arch ; 469(2): 327-338, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27900462

RESUMEN

The heat-sensitive transient receptor potential vanilloid 1 (TRPV1) channels are expressed in the peripheral and central nervous systems. However, there is no report on how the activation of TRPV1 causes the modulation of neuronal activity in the medullary respiratory center. We examined effects of capsaicin, a specific agonist of TRPV1 channels, on respiratory rhythm generation in brainstem-spinal cord preparation from newborn rats. Capsaicin induced a biphasic response in the respiratory rhythm (a transient decrease followed by an increase in the C4 rate). The second-phase excitatory effect (but not the initial inhibitory effect) in the biphasic response was partly blocked by capsazepine or AMG9810 (TRPV1 antagonists). Capsaicin caused strong desensitization. After its washout, the strength of C4 burst inspiratory activity was augmented once per four to five respiratory cycles. The preinspiratory and inspiratory neurons showed tonic firings due to membrane depolarization during the initial inhibitory phase. In the presence of TTX, capsaicin increased the fluctuation of the membrane potential of the CO2-sensitive preinspiratory neurons in the parafacial respiratory group (pFRG), accompanied by slight depolarization. The C4 inspiratory activity did not stop, even 60-90 min after the application of 50/100 µM capsaicin. Voltage-sensitive dye imaging demonstrated that the spatiotemporal pattern of the respiratory rhythm generating networks after application of capsaicin (50 µM, 70-90 min) was highly similar to the control. A histochemical analysis using TRPV1 channel protein antibodies and mRNA demonstrated that the TRPV1 channel-positive cells were widely distributed in the reticular formation of the medulla, including the pFRG. Our results showed that the application of capsaicin in the medulla has various influences on the respiratory center: transient inhibitory and subsequent excitatory effects on the respiratory rhythm and periodical augmentation of the inspiratory burst pattern. The effects of capsaicin were partially blocked by TRPV1 antagonists but could be also induced at least partially via the non-specific action. Our results also suggested a minor contribution of the TRPV1 channels to central chemoreception.


Asunto(s)
Tronco Encefálico/efectos de los fármacos , Capsaicina/farmacología , Respiración/efectos de los fármacos , Médula Espinal/efectos de los fármacos , Canales Catiónicos TRPV/agonistas , Acrilamidas/farmacología , Animales , Animales Recién Nacidos , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Capsaicina/análogos & derivados , Bulbo Raquídeo/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Neuronas/efectos de los fármacos , Ratas , Ratas Wistar , Canales Catiónicos TRPV/antagonistas & inhibidores , Imagen de Colorante Sensible al Voltaje/métodos
9.
J Phys Ther Sci ; 29(2): 212-215, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28265141

RESUMEN

[Purpose] This study investigated the short-term effects of a combination therapy consisting of repetitive facilitative exercises and orthotic treatment. [Subjects and Methods] The subjects were chronic post-stroke patients (n=27; 24 males and 3 females; 59.3 ± 12.4 years old; duration after onset: 35.7 ± 28.9 months) with limited mobility and motor function. Each subject received combination therapy consisting of repetitive facilitative exercises for the hemiplegic lower limb and gait training with an ankle-foot orthosis for 4 weeks. The Fugl-Meyer assessment of the lower extremity, the Stroke Impairment Assessment Set as a measure of motor performance, the Timed Up & Go test, and the 10-m walk test as a measure of functional ambulation were evaluated before and after the combination therapy intervention. [Results] The findings of the Fugl-Meyer assessment, Stroke Impairment Assessment Set, Timed Up & Go test, and 10-m walk test significantly improved after the intervention. Moreover, the results of the 10-m walk test at a fast speed reached the minimal detectible change threshold (0.13 m/s). [Conclusion] Short-term physiotherapy combining repetitive facilitative exercises and orthotic treatment may be more effective than the conventional neurofacilitation therapy, to improve the lower-limb motor performance and functional ambulation of chronic post-stroke patients.

10.
Biochim Biophys Acta ; 1841(4): 475-83, 2014 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-24370445

RESUMEN

We characterized certain physiological functions of cyanobacterial monoglucosyldiacylglycerol using a Synechocystis sp. PCC 6803 mutant in which the gene for monoglucosyldiacylglycerol synthase had been disrupted and its function complemented by inclusion of an Arabidopsis monogalactosyldiacylglycerol synthase gene. By using this method, we prepared the first viable monoglucosyldiacylglycerol-deficient mutant of cyanobacterium and found that monoglucosyldiacylglycerol is not essential for its growth and photosynthesis under a set of "normal growth conditions" when monogalactosyldiacylglycerol is adequately supplied by the Arabidopsis monogalactosyldiacylglycerol synthase. The mutant had healthy thylakoid membranes and normal pigment content. The membrane lipid composition of the mutant was similar with that of WT except lack of monoglucosyldiacylglycerol and a slight increase in the level of phosphatidylglycerol at both normal and low temperatures. However, the ratio of unsaturated fatty acids in monogalactosyldiacylglycerol and digalactosyldiacylglycerol was reduced in the mutant compared with WT. Although the growth of the mutant was indistinguishable with that of WT at normal growth temperature, it was markedly retarded at low temperature compared with that of WT. Our data indicated the possibility that cyanobacterial monogalactosyldiacylglycerol-synthesis pathway might be required for the adequate unsaturation level of fatty acids in galactolipids and affect the low-temperature sensitivity.


Asunto(s)
Galactolípidos/metabolismo , Galactosiltransferasas/genética , Synechocystis/genética , Adaptación Fisiológica/genética , Galactolípidos/biosíntesis , Galactosiltransferasas/metabolismo , Redes y Vías Metabólicas/genética , Mutación , Fotosíntesis , Synechocystis/metabolismo , Synechocystis/fisiología , Temperatura
11.
J Neurophysiol ; 114(2): 989-98, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26108952

RESUMEN

The transient receptor potential (TRP) channels are widely distributed in the central nervous system (CNS) and peripheral nervous system. We examined the effects of TRP ankyrin 1 (TRPA1) agonists (cinnamaldehyde and allyl isothiocyanate) on respiratory rhythm generation in brainstem-spinal cord preparations from newborn rats [postnatal days 0-3 (P0-P3)] and in in situ-perfused preparations from juvenile rats (P11-P13). Preparations were superfused with modified Krebs solution at 25-26°C, and activity of inspiratory C4 ventral root (or phrenic nerve) was monitored. In the newborn rat, an in vitro preparation of cinnamaldehyde (0.5 mM) induced typically biphasic responses in C4 rate: an initial short increase and subsequent decrease, then a gradual recovery of rhythm during 15 min of bath application. After washout, the respiratory rhythm rate further increased, remaining 200% of control for >120 min, indicating long-lasting facilitation. Allyl isothiocyanate induced effects similar to those of cinnamaldehyde. The long-lasting facilitation of respiratory rhythm was partially antagonized by the TRPA1 antagonist HC-030031 (10 µM). We obtained similar long-lasting facilitation in an in situ-perfused reparation from P11-P13 rats. On the basis of results from transection experiments of the rostral medulla and whole-cell recordings from preinspiratory neurons in the parafacial respiratory group (pFRG), we suggest that the rostral medulla, including the pFRG, is important to the induction of long-lasting facilitation. A histochemical analysis demonstrated a wide distribution of TRPA1 channel-positive cells in the reticular formation of the medulla, including the pFRG. Our findings suggest that TRPA1 channel activation could induce long-lasting facilitation of respiratory rhythm and provide grounds for future study on the roles of TRPA1 channels in the CNS.


Asunto(s)
Acroleína/análogos & derivados , Tronco Encefálico/efectos de los fármacos , Respiración/efectos de los fármacos , Fármacos del Sistema Respiratorio/farmacología , Médula Espinal/efectos de los fármacos , Canales Catiónicos TRPC/agonistas , Acetanilidas/farmacología , Acroleína/farmacología , Animales , Animales Recién Nacidos , Tronco Encefálico/fisiología , Estado de Descerebración , Inmunohistoquímica , Hibridación in Situ , Isotiocianatos/farmacología , Neuronas/efectos de los fármacos , Neuronas/fisiología , Periodicidad , Purinas/farmacología , Ratas Wistar , Médula Espinal/fisiología , Raíces Nerviosas Espinales/efectos de los fármacos , Raíces Nerviosas Espinales/fisiología , Canal Catiónico TRPA1 , Canales Catiónicos TRPC/antagonistas & inhibidores , Canales Catiónicos TRPC/metabolismo , Técnicas de Cultivo de Tejidos
12.
BMC Biol ; 12: 40, 2014 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-24885223

RESUMEN

BACKGROUND: Various senses and sensory nerve architectures of animals have evolved during adaptation to exploit diverse environments. In craniates, the trunk sensory system has evolved from simple mechanosensory neurons inside the spinal cord (intramedullary), called Rohon-Beard (RB) cells, to multimodal sensory neurons of dorsal root ganglia (DRG) outside the spinal cord (extramedullary). The fish and amphibian trunk sensory systems switch from RB cells to DRG during development, while amniotes rely exclusively on the DRG system. The mechanisms underlying the ontogenic switching and its link to phylogenetic transition remain unknown. RESULTS: In Xenopus, Six1 overexpression promoted precocious apoptosis of RB cells and emergence of extramedullary sensory neurons, whereas Six1 knockdown delayed the reduction in RB cell number. Genetic ablation of Six1 and Six4 in mice led to the appearance of intramedullary sensory neuron-like cells as a result of medial migration of neural crest cells into the spinal cord and production of immature DRG neurons and fused DRG. Restoration of SIX1 expression in the neural crest-linage partially rescued the phenotype, indicating the cell autonomous requirements of SIX1 for normal extramedullary sensory neurogenesis. Mouse Six1 enhancer that mediates the expression in DRG neurons activated transcription in Xenopus RB cells earlier than endogenous six1 expression, suggesting earlier onset of mouse SIX1 expression than Xenopus during sensory development. CONCLUSIONS: The results indicated the critical role of Six1 in transition of RB cells to DRG neurons during Xenopus development and establishment of exclusive DRG system of mice. The study provided evidence that early appearance of SIX1 expression, which correlated with mouse Six1 enhancer, is essential for the formation of DRG-dominant system in mice, suggesting that heterochronic changes in Six1 enhancer sequence play an important role in alteration of trunk sensory architecture and contribute to the evolution of the trunk sensory system.


Asunto(s)
Evolución Biológica , Proteínas de Homeodominio/metabolismo , Células Receptoras Sensoriales/metabolismo , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriología , Xenopus laevis/genética , Animales , Apoptosis/genética , Movimiento Celular , Elementos de Facilitación Genéticos/genética , Ganglios Espinales/citología , Ganglios Espinales/embriología , Ganglios Espinales/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas Fluorescentes Verdes/metabolismo , Proteínas de Homeodominio/genética , Ratones , Ratones Endogámicos C57BL , Cresta Neural/citología , Neuronas/citología , Neuronas/metabolismo , Células Receptoras Sensoriales/citología , Transactivadores/metabolismo , Proteínas de Xenopus/genética
13.
Plant Biotechnol J ; 12(6): 808-19, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24909748

RESUMEN

When cultivated under stress conditions, many plants and algae accumulate oil. The unicellular green microalga Chlamydomonas reinhardtii accumulates neutral lipids (triacylglycerols; TAGs) during nutrient stress conditions. Temporal changes in TAG levels in nitrogen (N)- and phosphorus (P)-starved cells were examined to compare the effects of nutrient depletion on TAG accumulation in C. reinhardtii. TAG accumulation and fatty acid composition were substantially changed depending on the cultivation stage before nutrient starvation. Profiles of TAG accumulation also differed between N and P starvation. Logarithmic-growth-phase cells diluted into fresh medium showed substantial TAG accumulation with both N and P deprivation. N deprivation induced formation of oil droplets concomitant with the breakdown of thylakoid membranes. In contrast, P deprivation substantially induced accumulation of oil droplets in the cytosol and maintaining thylakoid membranes. As a consequence, P limitation accumulated more TAG both per cell and per culture medium under these conditions. To enhance oil accumulation under P deprivation, we constructed a P deprivation-dependent overexpressor of a Chlamydomonas type-2 diacylglycerol acyl-CoA acyltransferase (DGTT4) using a sulphoquinovosyldiacylglycerol 2 (SQD2) promoter, which was up-regulated during P starvation. The transformant strongly enhanced TAG accumulation with a slight increase in 18 : 1 content, which is a preferred substrate of DGTT4. These results demonstrated enhanced TAG accumulation using a P starvation-inducible promoter.


Asunto(s)
Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/metabolismo , Diacilglicerol O-Acetiltransferasa/metabolismo , Fósforo/deficiencia , Aceites de Plantas/metabolismo , Plastidios/metabolismo , Regiones Promotoras Genéticas/genética , Chlamydomonas reinhardtii/crecimiento & desarrollo , Chlamydomonas reinhardtii/ultraestructura , Ácidos Grasos/metabolismo , Gotas Lipídicas , Nitrógeno/deficiencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Triglicéridos/metabolismo , Regulación hacia Arriba/genética
14.
Dev Biol ; 368(1): 95-108, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22659139

RESUMEN

The Six1 homeobox gene plays critical roles in vertebrate organogenesis. Mice deficient for Six1 show severe defects in organs such as skeletal muscle, kidney, thymus, sensory organs and ganglia derived from cranial placodes, and mutations in human SIX1 cause branchio-oto-renal syndrome, an autosomal dominant developmental disorder characterized by hearing loss and branchial defects. The present study was designed to identify enhancers responsible for the dynamic expression pattern of Six1 during mouse embryogenesis. The results showed distinct enhancer activities of seven conserved non-coding sequences (CNSs) retained in tetrapod Six1 loci. The activities were detected in all cranial placodes (excluding the lens placode), dorsal root ganglia, somites, nephrogenic cord, notochord and cranial mesoderm. The major Six1-expression domains during development were covered by the sum of activities of these enhancers, together with the previously identified enhancer for the pre-placodal region and foregut endoderm. Thus, the eight CNSs identified in a series of our study represent major evolutionarily conserved enhancers responsible for the expression of Six1 in tetrapods. The results also confirmed that chick electroporation is a robust means to decipher regulatory information stored in vertebrate genomes. Mutational analysis of the most conserved placode-specific enhancer, Six1-21, indicated that the enhancer integrates a variety of inputs from Sox, Pax, Fox, Six, Wnt/Lef1 and basic helix-loop-helix proteins. Positive autoregulation of Six1 is achieved through the regulation of Six protein-binding sites. The identified Six1 enhancers provide valuable tools to understand the mechanism of Six1 regulation and to manipulate gene expression in the developing embryo, particularly in the sensory organs.


Asunto(s)
Embrión de Mamíferos/metabolismo , Elementos de Facilitación Genéticos/genética , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Animales , Secuencia de Bases , Síndrome Branquio Oto Renal/genética , Embrión de Pollo , Secuencia Conservada/genética , Embrión de Mamíferos/citología , Embrión de Mamíferos/embriología , Evolución Molecular , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Proteínas de Homeodominio/metabolismo , Humanos , Hibridación in Situ , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microscopía Fluorescente , Datos de Secuencia Molecular , Órganos de los Sentidos/embriología , Órganos de los Sentidos/metabolismo , Homología de Secuencia de Ácido Nucleico , Vertebrados/embriología , Vertebrados/genética , Vertebrados/metabolismo
15.
J Physiol ; 591(13): 3433-49, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23652595

RESUMEN

Dystonia is characterized by excessive involuntary and prolonged simultaneous contractions of both agonist and antagonist muscles. Although the basal ganglia have long been proposed as the primary region, recent studies indicated that the cerebellum also plays a key role in the expression of dystonia. One hereditary form of dystonia, rapid-onset dystonia with parkinsonism (RDP), is caused by loss of function mutations of the gene for the Na pump α3 subunit (ATP1A3). Little information is available on the affected brain regions and mechanism for dystonia by the mutations in RDP. The Na pump is composed of α and ß subunits and maintains ionic gradients of Na(+) and K(+) across the cell membrane. The gradients are utilized for neurotransmitter reuptake and their alteration modulates neural excitability. To provide insight into the molecular aetiology of RDP, we generated and analysed knockout heterozygous mice (Atp1a3(+/-)). Atp1a3(+/-) showed increased symptoms of dystonia that is induced by kainate injection into the cerebellar vermis. Atp1a3 mRNA was highly expressed in Purkinje cells and molecular-layer interneurons, and its product was concentrated at Purkinje cell soma, the site of abundant vesicular γ-aminobutyric acid transporter (VGAT) signal, suggesting the presynaptic localization of the α3 subunit in the inhibitory synapse. Electrophysiological studies showed that the inhibitory neurotransmission at molecular-layer interneuron-Purkinje cell synapses was enhanced in Atp1a3(+/-) cerebellar cortex, and that the enhancement originated via a presynaptic mechanism. Our results shed light on the role of Atp1a3 in the inhibitory synapse, and potential involvement of inhibitory synaptic dysfunction for the pathophysiology of dystonia.


Asunto(s)
Corteza Cerebelosa/fisiología , Distonía/fisiopatología , ATPasa Intercambiadora de Sodio-Potasio/fisiología , Animales , Técnicas In Vitro , Interneuronas/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Actividad Motora , Neuronas/fisiología , Subunidades de Proteína/fisiología , Desempeño Psicomotor , Transmisión Sináptica
16.
Hum Reprod ; 28(2): 453-61, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23188113

RESUMEN

STUDY QUESTION: Does administration of androgen to female-to-male transsexual persons (FTMs) of reproductive age induce polycystic ovary (PCO) morphology? SUMMARY ANSWER: Administration of high-dose androgen to women causes pathognomonic changes to the ovarian cortex and stroma that resemble Stein-Leventhal syndrome but it does not induce PCO morphology. WHAT IS KNOWN ALREADY: Androgen is thought to play a key role in follicular development and to be involved in the pathophysiology of polycystic ovary syndrome (PCOS). In several experimental models, animals given high-dose androgen show ovarian changes similar to those in women with PCOS. In previous human studies, the ovaries of FTMs who received androgen for long periods also exhibited PCO morphology. STUDY DESIGN, SIZE, DURATION: We conducted a retrospective case-control study of women, all without PCOS, undergoing salpingo-oophorectomy. The case group consisted of 11 FTMs taking testosterone (duration range: 17 months to 14 years), while the control group consisted of 10 patients with gynaecologic malignancies who did not receive testosterone. PARTICIPANTS/MATERIALS, SETTING, METHODS: Resected ovaries from both groups were compared histologically with respect to changes in the cortex and stroma, and the number of follicles at each maturation stage. MAIN RESULTS AND THE ROLE OF CHANCE: Compared with controls, the FTM group had a thicker ovarian cortex (P = 0.0001), and more hyperplastic collagen (P = 0.001), ovarian stromal hyperplasia (P = 0.003) and stromal luteinization, i.e. luteinized stromal cells with a small dark central nucleus surrounded by clear cytoplasm (P = 0.004). Isolated clusters of such stromal luteinized cells were found only in the testosterone-treated ovaries of FTMs. The number of primordial follicles was similar in the two groups (P = 0.22). The numbers of early stage (primary, pre-antral and early antral) follicles, which are dependent on androgen, were also similar (P = 0.81), as were the numbers of antral follicles (P = 0.97). In contrast, significantly greater numbers of atretic follicles were seen in the FTM than that in the control group (P = 0.01). LIMITATIONS, REASON FOR CAUTION: In addition to the low numbers in the study groups, the histological changes in FTMs were investigated after testosterone administration, therefore it is possible that some of the observed changes were already present, before androgen administration. WIDER IMPLICATION OF THE FINDINGS: Our results are at variance with those of earlier studies and suggest that excessive androgen exposure in women of reproductive age may not be a factor in the pathogenesis of PCOS.


Asunto(s)
Ovario/efectos de los fármacos , Síndrome del Ovario Poliquístico/patología , Procedimientos de Reasignación de Sexo/efectos adversos , Testosterona/efectos adversos , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Ovario/patología , Estudios Retrospectivos , Testosterona/administración & dosificación , Testosterona/uso terapéutico
17.
Nature ; 446(7131): 97-101, 2007 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-17330045

RESUMEN

Cypoviruses and baculoviruses are notoriously difficult to eradicate because the virus particles are embedded in micrometre-sized protein crystals called polyhedra. The remarkable stability of polyhedra means that, like bacterial spores, these insect viruses remain infectious for years in soil. The environmental persistence of polyhedra is the cause of significant losses in silkworm cocoon harvests but has also been exploited against pests in biological alternatives to chemical insecticides. Although polyhedra have been extensively characterized since the early 1900s, their atomic organization remains elusive. Here we describe the 2 A crystal structure of both recombinant and infectious silkworm cypovirus polyhedra determined using crystals 5-12 micrometres in diameter purified from insect cells. These are the smallest crystals yet used for de novo X-ray protein structure determination. We found that polyhedra are made of trimers of the viral polyhedrin protein and contain nucleotides. Although the shape of these building blocks is reminiscent of some capsid trimers, polyhedrin has a new fold and has evolved to assemble in vivo into three-dimensional cubic crystals rather than icosahedral shells. The polyhedrin trimers are extensively cross-linked in polyhedra by non-covalent interactions and pack with an exquisite molecular complementarity similar to that of antigen-antibody complexes. The resulting ultrastable and sealed crystals shield the virus particles from environmental damage. The structure suggests that polyhedra can serve as the basis for the development of robust and versatile nanoparticles for biotechnological applications such as microarrays and biopesticides.


Asunto(s)
Cuerpos de Inclusión Viral/química , Reoviridae/química , Proteínas Virales/química , Animales , Bombyx/virología , Cristalización , Cristalografía por Rayos X , Cuerpos de Inclusión Viral/ultraestructura , Modelos Moleculares , Estructura Cuaternaria de Proteína , Reoviridae/genética , Reoviridae/fisiología , Reoviridae/ultraestructura , Proteínas Virales/metabolismo , Esparcimiento de Virus/fisiología
18.
Gynecol Endocrinol ; 29(6): 611-4, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23656393

RESUMEN

The purpose of this study was to clarify the risk factors and outcomes of placental polyp. This retrospective study was conducted on 1645 patients delivered or aborted in Sapporo Medical University from 2007 through 2011. Transvaginal color Doppler ultrasonography, hysteroscopy, contrast-enhanced MRI or 3D-CT angiography were performed. There were 1532 deliveries and 113 abortions. Seventy-one (4.3%) were ART-conceived and the remaining 1574 (95.7%) were non-ART pregnancies. Fifteen (0.91%) cases were confirmed as having placental polyp. Nine cases of placental polyp were identified among the 1574 (0.57%) as non-ART-related pregnancies, and 6 were identified among the 71 (8.5%) as ART-related pregnancies. Thus, pregnancies achieved through ART showed 20x greater incidence of complicating placental polyp than pregnancies achieved through without ART (p = 9.02 × 10(-6); odds ratio, 19.59; 95% confidence interval, 5.27-72.84, logistic regression analysis). Evaluation of blood flow within the polyp showed that in five of seven patients with low blood flow, the polyps spontaneously dropped off 79-115 days postpartum. Thus, ART-related pregnancies may be a risk factor of placental polyp, and spontaneous drop-off of the polyp is often observed in cases with low blood flow within the mass.


Asunto(s)
Enfermedades Placentarias/epidemiología , Pólipos/epidemiología , Técnicas Reproductivas Asistidas/efectos adversos , Aborto Inducido/efectos adversos , Aborto Inducido/estadística & datos numéricos , Aborto Espontáneo/epidemiología , Adulto , Femenino , Humanos , Placenta Accreta/epidemiología , Enfermedades Placentarias/diagnóstico por imagen , Pólipos/diagnóstico por imagen , Embarazo , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/etiología , Resultado del Embarazo/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Ultrasonografía
19.
Proc Natl Acad Sci U S A ; 107(51): 22084-9, 2010 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-21135214

RESUMEN

Opn5 (neuropsin) belongs to an independent group separated from the other six groups in the phylogenetic tree of opsins, for which little information of absorption characteristics and molecular properties of the members is available. Here we show that the chicken Opn5 (cOpn5m) is a UV-sensitive bistable pigment that couples with Gi subtype of G protein. The recombinant expression of cOpn5m in HEK 293s cells followed by the addition of 11-cis- and all-trans-retinal produced UV light-absorbing and visible light-absorbing forms, respectively. These forms were interconvertible by UV and visible light irradiations, respectively, indicating that cOpn5m is a bistable pigment. The absorption maxima of these forms were estimated to be 360 and 474 nm, respectively. The GTPγS binding assay clearly showed that the visible light-absorbing form having all-trans-retinal activates Gi type of G protein, whereas no Gt or Gq activation ability was observed. Immunohistochemical studies using an antibody against cOpn5m clearly showed that this pigment is localized within some types of amacrine cells and some cells in the ganglion cell layer of the retinas, the vast majority of cells in the pineal gland and serotonin-positive cells in the paraventricular organ. Because cOpn5m is the only UV-sensitive opsin among the opsins found so far in chicken, this study provides the molecular basis for UV reception in chicken.


Asunto(s)
Células Amacrinas/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Retinaldehído/metabolismo , Opsinas de Bastones/metabolismo , Rayos Ultravioleta , Animales , Pollos , Activación Enzimática/efectos de los fármacos , Activación Enzimática/efectos de la radiación , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/genética , Guanosina 5'-O-(3-Tiotrifosfato)/farmacología , Células HEK293 , Humanos , Retinaldehído/genética , Opsinas de Bastones/genética
20.
Rinsho Byori ; 61(10): 955-60, 2013 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-24372001

RESUMEN

A large number of clinical laboratory technologists are qualified as diabetes educators; however, few of them actually participate in teaching patients. This is partially because it is difficult to balance their routine laboratory tasks and the work of a diabetes educator. We have introduced ultrasonic examinations of the ophthalmic artery, inspection of the R-R interval and current perceptual-threshold inspection for the early diagnosis of diabetic complications, and we have been contributing to the good medical care for diabetes. Furthermore, to care for diabetic foot lesions, clinical laboratory technologists have participated in checking diabetic patients' feet since 2007. In concrete terms, we examine the feet of diabetic patients, take digital pictures of the feet, and write a report, while preparing for thermographic examination of the patient. At the same time, we give simple guidance about foot care. Technologists cannot perform medical treatment; however, this has been accepted by medical staff because we only check foot lesions. We make use of existing medical imaging and reporting systems in the physiological laboratory, so doctors and nurses on the diabetic care team can always obtain information about the patients. Such actions have a good reputation not only among medical staff but also among diabetic patients.


Asunto(s)
Diabetes Mellitus/diagnóstico , Grupo de Atención al Paciente , Diabetes Mellitus/terapia , Diagnóstico Precoz , Humanos , Laboratorios de Hospital , Personal de Laboratorio Clínico , Factores de Riesgo
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