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1.
Hum Mol Genet ; 32(9): 1524-1538, 2023 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-36611008

RESUMEN

Drosophila is an excellent model organism for studying human neurodegenerative diseases (NDs). However, there is still almost no experimental system that could directly observe the degeneration of neurons and automatically quantify axonal degeneration. In this study, we created MeDUsA (a 'method for the quantification of degeneration using fly axons'), a standalone executable computer program based on Python that combines a pre-trained deep-learning masking tool with an axon terminal counting tool. This software automatically quantifies the number of retinal R7 axons in Drosophila from a confocal z-stack image series. Using this software, we were able to directly demonstrate that axons were degenerated by the representative causative genes of NDs for the first time in Drosophila. The fly retinal axon is an excellent experimental system that is capable of mimicking the pathology of axonal degeneration in human NDs. MeDUsA rapidly and accurately quantifies axons in Drosophila photoreceptor neurons. It enables large-scale research into axonal degeneration, including screening to identify genes or drugs that mediate axonal toxicity caused by ND proteins and diagnose the pathological significance of novel variants of human genes in axons.


Asunto(s)
Proteínas de Drosophila , Enfermedades Neurodegenerativas , Animales , Humanos , Drosophila/genética , Drosophila/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Axones/metabolismo , Neuronas/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo
2.
J Biol Chem ; 299(10): 105168, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37595869

RESUMEN

Alternative splicing in the 3'UTR of mammalian genes plays a crucial role in diverse biological processes, including cell differentiation and development. SAM68 is a key splicing regulator that controls the diversity of 3'UTR isoforms through alternative last exon (ALE) selection. However, the tissue/cell type-specific mechanisms underlying the splicing control at the 3' end and its functional significance remain unclear. Here, we show that SAM68 regulates ALE splicing in a dose-dependent manner and the neuronal splicing is differentially regulated depending on the characteristics of the target transcript. Specifically, we found that SAM68 regulates interleukin-1 receptor-associated protein splicing through the interaction with U1 small nuclear ribonucleoprotein. In contrast, the ALE splicing of protocadherin-15 (Pcdh15), a gene implicated in several neuropsychiatric disorders, is independent of U1 small nuclear ribonucleoprotein but modulated by the calcium/calmodulin-dependent protein kinase signaling pathway. We found that the aberrant ALE selection of Pcdh15 led to a conversion from a membrane-bound to a soluble isoform and consequently disrupted its localization into excitatory and inhibitory synapses. Notably, the neuronal expression of the soluble form of PCDH15 preferentially affected the number of inhibitory synapses. Moreover, the soluble form of PCDH15 interacted physically with α-neurexins and further disrupted neuroligin-2-induced inhibitory synapses in artificial synapse formation assays. Our findings provide novel insights into the role of neuron-specific alternative 3'UTR isoform selections in synapse development.

3.
Dev Growth Differ ; 66(3): 205-218, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38403285

RESUMEN

Vision is formed by the transmission of light stimuli to the brain through axons extending from photoreceptor cells. Damage to these axons leads to loss of vision. Despite research on neural circuit regeneration through transplantation, achieving precise axon projection remains challenging. To achieve optic nerve regeneration by transplantation, we employed the Drosophila visual system. We previously established a transplantation method for Drosophila utilizing photoreceptor precursor cells extracted from the eye disc. However, little axonal elongation of transplanted cells into the brain, the lamina, was observed. We verified axonal elongation to the lamina by modifying the selection process for transplanted cells. Moreover, we focused on N-cadherin (Ncad), a cell adhesion factor, and Twinstar (Tsr), which has been shown to promote actin reorganization and induce axon elongation in damaged nerves. Overexpression of Ncad and tsr promoted axon elongation to the lamina, along with presynaptic structure formation in the elongating axons. Furthermore, overexpression of Neurexin-1 (Nrx-1), encoding a protein identified as a synaptic organizer, was found to not only promote presynapse formation but also enhance axon elongation. By introducing Ncad, tsr, and Nrx-1, we not only successfully achieved axonal projection of transplanted cells to the brain beyond the retina, but also confirmed the projection of transplanted cells into a deeper ganglion, the medulla. The present study offers valuable insights to realize regeneration through transplantation in a more complex nervous system.


Asunto(s)
Actinas , Adhesión Celular , Drosophila , Células Fotorreceptoras , Animales , Actinas/metabolismo , Axones/metabolismo , Drosophila/genética , Drosophila/metabolismo , Células Fotorreceptoras/metabolismo , Sinapsis/metabolismo
4.
Chirality ; 36(1): e23625, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37880144

RESUMEN

In the study of phthalocyanine complexes using magnetic circular dichroism (MCD) spectroscopy, the electronic structure of excited states is generally discussed based on the rigid-shift approximation, in which the band profiles for left-handed circularly polarized (lcp) and right-handed circularly polarized (rcp) light are assumed to be the same. This assumption may not necessarily be valid for cases where there are multiple initial states having different geometries. Magnetic circularly polarized luminescence (MCPL) from phthalocyanine complexes can be regarded as an example of such cases, since the two degenerate emission states are split in a magnetic field and can undergo a structural deformation. Here, we investigated an alternative approach, where the lcp and rcp components are independently determined. This method, which we refer to as the direct-separation approach, allows direct determination of the distribution of the two emission states as well as the orbital angular momentum L z $$ \left|{L}_z\right| $$ . Using this approach, L z $$ \left|{L}_z\right| $$ and the distribution were determined from MCD and MCPL spectra of a series of phthalocyanine complexes. Comparison of the two methods shows that the rigid-shift and the direct-separation approaches give practically equivalent results for the systems under study, but the latter is advantageous for systems where the former is not applicable.

5.
Chirality ; 36(2): e23648, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38384149

RESUMEN

Magnetic circular dichroism (MCD) spectroscopy is a powerful method for evaluating the electronic structure and magnetic and optical properties of molecules. In particular, MCD measurements have been performed on phthalocyanines and porphyrins with various central metal ions, axial ligands, and substituents to elucidate their properties. It is essential to develop a robust high-throughput technique to perform these measurements comprehensively and efficiently. However, MCD spectroscopy requires very high optical quality for each component of the instrument, and even slight cell distortions can impair the baseline flatness. Consequently, when versatility and data quality are important, an optical system designed for a microplate reader is not suitable for the MCD spectrometer. Therefore, in this study, we develop a new magnetic flow-through cell and combine it with an existing CD spectrometer and autosampler to construct a high-throughput system. The effectiveness and performance of this new system are then evaluated. In addition, based on the MCD and absorption spectra of various phthalocyanine complexes, the effects of substituents and solvents on their magnetic and optical properties and the causes of these effects are discussed. The results demonstrate that this system is effective for the evaluation of the physicochemical properties of various phthalocyanine complexes.

6.
Nurs Health Sci ; 26(2): e13135, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38866383

RESUMEN

Pregnant women experience medical and psychological difficulties in their daily lives during disasters. Since the care provided to them in disaster situations is unclear, it is necessary to better understand their experiences. This study aims to identify the maternal experiences of pregnant women during natural disasters. This research employed a modified grounded theory approach. Twenty-three pregnant women, living in disaster-affected areas, were interviewed. The research methods were utilized and interpretive analysis was conducted, resulting in a diagram and storyline to describe the process. The characteristics of the maternal experiences fluctuated between "being unable to face pregnancy because of the disaster response" and "facing the fact of being pregnant." To maintain a fluctuation between their affected life and their pregnant life, it was necessary to control the weighting between "securing a safe and secure place," "encountering support based on pregnancy," and "signs from the fetus." Clarifying the maternal experiences of pregnant women living in disaster areas revealed a multilayered structure of categories and relationships. This study suggests that understanding the structure of fluctuations and control is critical for the nursing practice.


Asunto(s)
Teoría Fundamentada , Desastres Naturales , Mujeres Embarazadas , Investigación Cualitativa , Humanos , Femenino , Embarazo , Adulto , Mujeres Embarazadas/psicología
7.
Nihon Koshu Eisei Zasshi ; 71(4): 231-239, 2024 Apr 25.
Artículo en Japonés | MEDLINE | ID: mdl-38123332

RESUMEN

Objectives Interviewing people about their health behaviour in specific health checkups (SHCs) is thought to promote awareness of and help improve such behaviour. The standard questionnaire (SQ) for SHCs consists of 22 items presented in the guidelines of the Ministry of Health, Labour, and Welfare. However, using items other than those necessary for stratification for specific health guidance (SHG) is optional. We believe that clarifying the actual utilization of SQ items could contribute to improving the procedure used for the fourth SHCs and SHG, which will be initiated in 2024. This study seeks to clarify the actual utilization of the SQ for (1) conducting SHCs, (2) planning, implementing, and evaluating SHG and health programs aimed at preventing lifestyle-related diseases, and (3) planning, implementing, and evaluating the data health plan.Methods We enrolled 3,179 people from 1,741 departments in charge of national health insurance, 47 Japan Health Insurance Association branches, and 1,391 health insurance societies across all municipalities in Japan. One participant among the study participants was the main person in charge of SHCs and SHG at each facility. We conducted a self-reported survey on the implementation of SHCs and SHG in February 2022. This study was approved by the ethics review board of the institution to which the first author belongs.Results A total of 1,221 (38.4%) were received. The proportions of valid responses from national health insurance departments, Japan Health Insurance Association branches, and health insurance societies were 816 (46.9%), 47 (100%), and 358 (25.7%), respectively. Over 96% of responders used the group SHCs method, and over 93% of those adopting the individual SHCs method used each of the 22 SQ items. However, 187 (18.2%) responders found it difficult to use the item "If you had the opportunity to receive health guidance for lifestyle improvement, would you take it?" The reason was that the on-request SHG system was misunderstood. Additionally, only approximately 50% of respondents used the SQ to develop, implement, and evaluate their health program.Conclusion We believe there will be no problem in implementing the SQ even if using all its component items is required. However, the aforementioned item needs to be revised. Methods to encourage health insurers and their supporters to use the SQ for health-related data collection and health program planning should be devised.


Asunto(s)
Examen Físico , Humanos , Encuestas y Cuestionarios , Japón , Femenino , Masculino , Examen Físico/métodos , Persona de Mediana Edad , Conductas Relacionadas con la Salud , Adulto , Anciano
8.
J Infect Chemother ; 29(11): 1054-1060, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37507087

RESUMEN

We previously reported the finding of symptom relief in a randomized controlled trial with the combined use of kakkonto and shosaikotokakikyosekko added to conventional treatment in patients with coronavirus disease 2019 (COVID-19). For further evaluation, we performed post hoc analysis focused on symptom disappearance without recurrence, to determine a clearer effect of Kampo medicine. Patients with mild and moderate COVID-19 were randomly allocated to a control group receiving symptomatic therapy or a Kampo group receiving kakkonto (2.5 g) with shosaikotokakikyosekko (2.5 g) three times daily in addition to symptomatic therapy. The data of 161 patients (Kampo group, n = 81; control group, n = 80) were analyzed post hoc for the time to symptom disappearance. Kaplan-Meier and Cox proportional hazard estimates of disappearance of symptoms showed that all and each symptom targeted in this study disappeared faster in the Kampo group than in the control group, although not statistically significant (all symptomatic cases; hazard ratio [HR] 3.73, 95% confidence interval [CI] 0.46-29.98, log-rank p = 0.1763). In a supplemental assessment using covariate adjustment and competing risk analysis, fever disappeared faster in the Kampo group than in the control group (all symptomatic cases, HR 1.62, 95% CI 0.99-2.64, p = 0.0557; unvaccinated cases, HR 1.68, 95% CI 1.00-2.83, p = 0.0498) and shortness of breath disappeared significantly faster in Kampo group than in control group (all symptomatic cases, HR 1.92, 95% CI 1.07-3.42, p = 0.0278; unvaccinated cases, HR 2.15, 95% CI 1.17-3.96, p = 0.0141). These results demonstrate the advantages of Kampo treatment for acute COVID-19.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19 , Medicamentos Herbarios Chinos , Medicina Kampo , Humanos , COVID-19/terapia , Pueblos del Este de Asia , Medicina Kampo/métodos , Medicamentos Herbarios Chinos/uso terapéutico , Tratamiento Farmacológico de COVID-19/métodos , Japón
9.
Tohoku J Exp Med ; 260(3): 231-244, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37164697

RESUMEN

The coronavirus disease 2019 (COVID-19) pandemic remains a global public health concern. The clinical course and risk of developing severe illness among patients with COVID-19 who are at low-risk of severe COVID-19 remain uncertain. This retrospective cohort study from an isolation facility for low-risk COVID-19 patients in Japan evaluated the potential risks for severe disease with hypoxia (SpO2 ≤ 93%) or experiencing prolonged isolation period longer than 14 days with persistent acute symptoms. The study was performed before the spread of the alpha variant in the country and before the start of a nationwide mass vaccination campaign against COVID-19. Among the 929 participants with reliable outcome data regarding the development of hypoxia, 63 (6.8%) developed severe disease with hypoxia during their stays at the facility. Higher age [adjusted odds ratio (aOR), 1.08; 95% confidence interval (CI), 1.06-1.10] and male sex (aOR, 4.70; 95% CI, 2.39-9.22) were associated with this outcome. As for the experience of prolonged isolation period, higher age (aOR, 1.02; 95% CI, 1.01-1.04), atopic diseases (aOR, 1.69, 95% CI, 1.09-2.64), presence of cough at onset (aOR, 1.64; 95% CI, 1.09-2.48), and prescription of oral antibiotics before positive test results for COVID-19 (aOR, 2.37; 95% CI, 1.33-4.22) were associated with this outcome. In summary, 5-10% of low-risk COVID-19 patients later develop hypoxia. Older age and male sex were associated with both the development of hypoxia and prolonged acute symptoms. The unnecessary prescription of antibiotics before COVID-19 diagnosis may prolong COVID-19 symptoms.


Asunto(s)
COVID-19 , Humanos , Masculino , COVID-19/epidemiología , SARS-CoV-2 , Estudios Retrospectivos , Prueba de COVID-19 , Hipoxia
10.
Cancer Sci ; 113(5): 1779-1788, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35253340

RESUMEN

Intraperitoneal administration of anticancer nanoparticles is a rational strategy for preventing peritoneal dissemination of colon cancer due to the prolonged retention of nanoparticles in the abdominal cavity. However, instability of nanoparticles in body fluids causes inefficient retention, reducing its anticancer effects. We have previously developed anticancer nanoparticles containing tocopheryl succinate, which showed high in vivo stability and multifunctional anticancer effects. In the present study, we have demonstrated that peritoneal dissemination derived from colon cancer was prevented by intraperitoneal administration of tocopheryl succinate nanoparticles. The biodistribution of tocopheryl succinate nanoparticles was evaluated using inductively coupled plasma mass spectroscopy and imaging analysis in mice administered quantum dot encapsulated tocopheryl succinate nanoparticles. Intraperitoneal administration of tocopheryl succinate nanoparticles showed longer retention in the abdominal cavity than by its intravenous (i.v.) administration. Moreover, due to effective biodistribution, tumor growth was prevented by intraperitoneal administration of tocopheryl succinate nanoparticles. Furthermore, the anticancer effect was attributed to the inhibition of cancer cell proliferation and improvement of the intraperitoneal microenvironment, such as decrease in the levels of vascular endothelial growth factor A, interleukin 10, and M2-like phenotype of tumor-associated macrophages. Collectively, intraperitoneal administration of tocopheryl succinate nanoparticles is expected to have multifaceted antitumor effects against colon cancer with peritoneal dissemination.


Asunto(s)
Neoplasias del Colon , Nanopartículas , Animales , Neoplasias del Colon/tratamiento farmacológico , Humanos , Ratones , Nanopartículas/química , Succinatos/farmacología , Distribución Tisular , Microambiente Tumoral , Factor A de Crecimiento Endotelial Vascular , alfa-Tocoferol/química , alfa-Tocoferol/farmacología
11.
Epilepsia ; 63(7): 1704-1713, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35485955

RESUMEN

OBJECTIVE: This study was undertaken to evaluate the efficacy, safety, and economic impact of diazepam suppositories with as-needed acetaminophen in comparison with as-needed acetaminophen alone for prevention of seizure recurrence during the same fever episode in suspected pediatric simple febrile seizures (SFS). METHODS: This single-center, prospective, observational study was conducted from July 29, 2019 to February 15, 2021 at a children's hospital. Children aged 6 months to 60 months presenting to the emergency department with suspected SFS were included. Participants receiving both diazepam suppositories and as-needed acetaminophen were compared with those receiving as-needed acetaminophen alone. The primary outcome was seizure recurrence during the same fever episode. The secondary outcomes included the incidence of central nervous system (CNS) pathologies, adverse events, and medical costs. RESULTS: Of the 316 participants, 228 (72.2%) had their first febrile seizure. Diazepam (.3-.5 mg/kg for up to two doses) was administered to 88 of 316 patients (27.8%). The outcomes were available for 306 patients. The recurrence rate was 3.5% (3/85) in the patients receiving diazepam with as-needed acetaminophen and 12.2% (27/221) in the patients receiving as-needed acetaminophen alone (relative risk = .29, 95% confidence interval [CI] = .09-.93, p = .03). The adjusted odds ratio of diazepam administration against recurrence was .23 (95% CI = .07-.78, p = .02). None of the patients had a CNS pathology. No severe adverse events occurred, although mild ataxia was observed significantly more often in the patients receiving diazepam and as-needed acetaminophen (29.4% vs. 18.7%, p = .04). The median medical cost was US $199 (interquartile range [IQR] = 86-244) for the group receiving both medications and US $202 (IQR = 114-242) for the group receiving as-needed acetaminophen alone. SIGNIFICANCE: Compared with as-needed acetaminophen alone, diazepam with as-needed acetaminophen may reduce seizure recurrence more during the same fever episode without severe adverse events or additional costs in children with suspected SFS.


Asunto(s)
Convulsiones Febriles , Acetaminofén/efectos adversos , Niño , Diazepam/efectos adversos , Fiebre/inducido químicamente , Fiebre/prevención & control , Humanos , Lactante , Estudios Prospectivos , Recurrencia , Convulsiones Febriles/inducido químicamente , Convulsiones Febriles/prevención & control , Supositorios
12.
Tohoku J Exp Med ; 257(3): 241-249, 2022 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-35598972

RESUMEN

Coronavirus disease 2019 (COVID-19) causes a variety of pain symptoms in the acute phase. Severe chest pain suddenly occurs even without abnormalities on examination and is sometimes refractory to analgesics. Such pain is a clinical concern in care facilities with limited resources, and this is the first report on the use of saikanto for its treatment. In Miyagi Prefecture, Japan, COVID-19 patients with mild symptoms were admitted to a hotel that operated as an isolation facility, and their symptoms were observed. In this article, we report four cases in which chest pain comorbid with mild to moderate COVID-19 was successfully treated with saikanto, a traditional Japanese (Kampo) medicine. The patients presented with chest pain and underwent medical examination at the facility. Two patients had severe chest pain refractory to acetaminophen. Critical cardiopulmonary diseases were ruled out in all the patients, and three patients had features of pneumonia on chest radiograph. Medications, including saikanto, were administered to the patients. The patients' chest pain and other symptoms improved 1-4 days after the administration of saikanto, and they left the care facility without hospitalization. The cause of the chest pain experienced by these patients is unclear, but we speculate that it could be minimal pleural inflammation or neuropathy. Previous pharmacological studies have suggested anti-inflammatory and analgesic properties of the crude drugs that constitute saikanto. This case report suggests that saikanto could be a treatment option for chest pain refractory to analgesics in patients with mild to moderate COVID-19.


Asunto(s)
COVID-19 , COVID-19/complicaciones , Dolor en el Pecho/complicaciones , Humanos , Japón , Medicina Kampo
13.
Phys Chem Chem Phys ; 23(9): 5074-5078, 2021 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-33616128

RESUMEN

Optically inactive, paramagnetic Ir(iii)(ppy)3 and Ir(iii)(ppy)2(acac) (ppy: 2-phenylpyridinate and acac: acetylacetonate) showed nearly mirror-symmetric magnetic circularly polarised luminescence (MCPL) spectra in dilute dichloromethane and dimethyl sulfoxide under N-up and S-up geometries in a 1.6-T magnetic field. However, the MCPL signs of Ir(iii)(ppy)3 and Ir(iii)(ppy)2(acac) under the same N-up (or S-up) Faraday geometry were opposite to each other when one ppy was replaced with an acac. This ligand exchange approach provides facile control of the MCPL sign, irrespective of the Faraday geometry.

14.
Tohoku J Exp Med ; 254(2): 71-80, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34108344

RESUMEN

Olfactory disorders are one of the characteristic symptoms of the coronavirus disease of 2019 (COVID-19), which causes infection and inflammation of the upper and lower respiratory tract. To our knowledge, there are no treatments for COVID-19-related olfactory disorder. Here, we report five olfactory disorder cases in COVID-19, treated using the Japanese traditional (Kampo) medicine, kakkontokasenkyushin'i. We treated five patients with mild COVID-19 at an isolation facility using Kampo medicine, depending on their symptoms. Patients with the olfactory disorder presented with a blocked nose, nasal discharge or taste impairment. Physical examination using Kampo medicine showed similar findings, such as a red tongue with red spots and sublingual vein congestion, which presented as blood stasis and inflammation; thus, we prescribed the Kampo medicine, kakkontokasenkyushin'i. After administration, the numeric rating scale scores of the smell impairment improved within 3 days from 9 to 3 in case 1, from 10 to 0 in case 2, from 9 to 0 in case 3, from 5 to 0 in case 4, and from 9 to 0 within 5 days in case 5. Following the treatment, other common cold symptoms were also alleviated. Kakkontokasenkyushin'i can be used for treating nasal congestion, rhinitis, and inflammation in the nasal mucosa. The olfactory disorder in COVID-19 has been reportedly associated with inflammation and congestion, especially in the olfactory bulb and olfactory cleft. Kakkontokasenkyushin'i may be one of the treatment alternatives for the olfactory disorder with rhinitis in patients with COVID-19.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Medicina Kampo/métodos , Trastornos del Olfato/tratamiento farmacológico , Preparaciones de Plantas/uso terapéutico , Adolescente , Adulto , COVID-19/complicaciones , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/farmacología , Femenino , Humanos , Japón , Masculino , Trastornos del Olfato/complicaciones , Trastornos del Olfato/virología , Preparaciones de Plantas/química , Preparaciones de Plantas/farmacología , Rinitis/complicaciones , Rinitis/tratamiento farmacológico , Rinitis/virología , SARS-CoV-2/fisiología , Olfato/efectos de los fármacos , Resultado del Tratamiento , Adulto Joven
15.
J Neurosci ; 39(30): 5861-5880, 2019 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-31175213

RESUMEN

Columnar structure is a basic unit of the brain, but the mechanism underlying its development remains largely unknown. The medulla, the largest ganglion of the Drosophila melanogaster visual center, provides a unique opportunity to reveal the mechanisms of 3D organization of the columns. In this study, using N-cadherin (Ncad) as a marker, we reveal the donut-like columnar structures along the 2D layer in the larval medulla that evolves to form three distinct layers in pupal development. Column formation is initiated by three core neurons, R8, R7, and Mi1, which establish distinct concentric domains within a column. We demonstrate that Ncad-dependent relative adhesiveness of the core columnar neurons regulates their relative location within a column along a 2D layer in the larval medulla according to the differential adhesion hypothesis. We also propose the presence of mutual interactions among the three layers during formation of the 3D structures of the medulla columns.SIGNIFICANCE STATEMENT The columnar structure is a basic unit of the brain, but its developmental mechanism remains unknown. The medulla, the largest ganglion of the fly visual center, provides a unique opportunity to reveal the mechanisms of 3D organization of the columns. We reveal that column formation is initiated by three core neurons that establish distinct concentric domains within a column. We demonstrate the in vivo evidence of N-cadherin-dependent differential adhesion among the core columnar neurons within a column along a 2D layer in the larval medulla. The 2D larval columns evolve to form three distinct layers in the pupal medulla. We propose the presence of mutual interactions among the three layers during formation of the 3D structures of the medulla columns.


Asunto(s)
Cadherinas/análisis , Proteínas de Drosophila/análisis , Bulbo Raquídeo/química , Bulbo Raquídeo/citología , Neuronas/química , Animales , Animales Modificados Genéticamente , Cadherinas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Femenino , Masculino , Bulbo Raquídeo/metabolismo , Neuronas/metabolismo
16.
Genes Cells ; 24(7): 496-510, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31124270

RESUMEN

In the Drosophila brain, neurons form genetically specified synaptic connections with defined neuronal targets. It is proposed that each central nervous system neuron expresses specific cell surface proteins, which act as identification tags. Through an RNAi screen of cell surface molecules in the Drosophila visual system, we found that the cell adhesion molecule Klingon (Klg) plays an important role in repressing the ectopic formation of extended axons, preventing the formation of excessive synapses. Cell-specific manipulation of klg showed that Klg is required in both photoreceptors and the glia, suggesting that the balanced homophilic interaction between photoreceptor axons and the glia is required for normal synapse formation. Previous studies suggested that Klg binds to cDIP and our genetic analyses indicate that cDIP is required in glia for ectopic synaptic repression. These data suggest that Klg play a critical role together with cDIP in refining synaptic specificity and preventing unnecessary connections in the brain.


Asunto(s)
Moléculas de Adhesión Celular/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiología , Proteínas del Ojo/metabolismo , Neuroglía/fisiología , Células Fotorreceptoras de Invertebrados/fisiología , Sinapsis/fisiología , Vías Visuales , Animales , Animales Modificados Genéticamente/genética , Animales Modificados Genéticamente/fisiología , Axones/fisiología , Moléculas de Adhesión Celular/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas del Ojo/genética , Femenino
17.
Dev Growth Differ ; 60(7): 442-453, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29989152

RESUMEN

Blindness caused by the disconnection between photoreceptor cells and the brain can be cured by restoring this connection through the transplantation of retinal precursor neurons. However, even after transplanting these cells, it is still unclear how to guide the axons over the long distance from the retina to the brain. To establish a method of guiding the axons of transplanted neurons, we used the Drosophila visual system. By testing different conditions, including the dissociation and preincubation length, we have successfully established a method to transplant photoreceptor precursor cells isolated from the developing eye discs of third-instar larvae into the adult retina. Moreover, we overexpressed N-cadherin (CadN) in the transplant, since it is known to be broadly expressed in the optic lobe well after developmental stages, continuing through adult stages. We found that promoting the cell adhesive properties using CadN enhances the axonal length of the grafted photoreceptor neurons and therefore is useful for future transplantation. We tested the overexpression of a CadN::Frazzled chimeric receptor and found that there was no difference in axonal length from our wild-type transplants, suggesting that the intracellular domain of CadN is necessary for axonal elongation. Altogether, using the Drosophila visual system, we have established an excellent platform for exploring the molecules required for proper axon extension of transplanted neuronal cells. Future studies building from this platform will be useful for regenerative therapy of the human nervous system based on transplantation.


Asunto(s)
Drosophila , Células Fotorreceptoras/citología , Células Fotorreceptoras/trasplante , Retina/citología , Animales
18.
Int Arch Allergy Immunol ; 177(3): 259-268, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30134240

RESUMEN

BACKGROUND: Partially hydrolyzed cow's milk protein-based formula (pHF) possesses low allergenicity. Here, we investigate the safety and efficacy of oral immunotherapy using pHF for children with cow's milk protein allergy (CMPA). OBJECTIVES: A randomized, double-blind, controlled single-center trial was conducted to evaluate the efficacy and safety of pHF oral immunotherapy in children with CMPA. METHODS: Participants were randomized into double-blind pHF-pHF and extensively hydrolyzed cow's milk protein-based formula (eHF)-pHF groups. During this phase, the pHF-pHF group received pHF and the eHF-pHF group received eHF. During the open phase, all participants received pHF. The primary end point was a change in thresholds between baseline and the end of the first phase. Secondary end points were changes in thresholds between baseline and the end of the second phase, and casein-specific immunoglobulin (Ig)E, IgG4, and basophil activation. RESULTS: Twenty-five children, aged 1-9 years, were randomized into pHF-pHF and eHF-pHF groups. The threshold between baseline and the end of the first phase was significantly elevated in the pHF-pHF group (p = 0.048), but not in the eHF-pHF group. The threshold between other phases did not change significantly in either group. There were significant decreases in casein-specific IgE antibody levels between baseline and the second phase in the eHF-pHF group (p = 0.014). No participants suffered systemic allergic reactions requiring adrenaline or systemic corticosteroids after receiving the formulas. CONCLUSIONS: The results of this trial suggest that, in children with CMPA, tolerance to cow's milk might be safely enhanced by intake of pHF, relative to that of eHF.


Asunto(s)
Alérgenos/administración & dosificación , Inmunoterapia/métodos , Hipersensibilidad a la Leche/terapia , Proteínas de la Leche/administración & dosificación , Administración Oral , Alérgenos/química , Alérgenos/inmunología , Animales , Caseínas/inmunología , Niño , Preescolar , Femenino , Humanos , Inmunoglobulina E/sangre , Lactante , Masculino , Hipersensibilidad a la Leche/inmunología , Proteínas de la Leche/química , Proteínas de la Leche/inmunología
19.
Biochem Biophys Res Commun ; 493(2): 1030-1036, 2017 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-28939043

RESUMEN

Neurexins (NRXs) and neuroligins (NLs) play important roles in synapse specification. The alternatively spliced segment 4 (AS4) of NRX genes (Nrxn) is a critical element in selective trans-synaptic interactions. However, the role of splicing of NRXs and NLs in synapse specification is not fully understood. To investigate the exact role of splice-dependent NRX-NL interaction in the specification of glutamatergic and gamma-aminobutyric acid (GABA)-ergic synapses in the cerebellum, we evaluated the synaptogenic receptor activity of NL1/2/3 isoforms in a neuron-fibroblast co-culture system, in which the Nrxn AS4 segments are manipulated using SLM2, a selective and dominant regulator of AS4 splicing. We show that ectopic SLM2 expression (SLM2 E/E) causes marked skipping of exon 20 of AS4 in cerebellar neuron culture. Whereas NLs can induce VAMP2+ presynaptic contacts from mainly glutamatergic neurons in both uninfected (control) and SLM2 E/E co-cultures, they induce VGAT+ GABAergic contacts in the control culture, but not properly in the SLM2 E/E culture. Furthermore, Nrxn3 is responsible for the NL-induced assembly of GABAergic synapses in co-culture. Importantly, lentivirus-based expression of Nrxn3 containing exon 20 restores the reduced NL-induced GABAergic contacts in the SLM2 E/E co-culture. Therefore, our findings may provide further insights into NRX-NL mediated synapse specification.


Asunto(s)
Empalme Alternativo , Moléculas de Adhesión Celular Neuronal/metabolismo , Cerebelo/citología , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas de Unión al ARN/metabolismo , Animales , Proteínas de Unión al Calcio , Moléculas de Adhesión Celular Neuronal/genética , Células Cultivadas , Cerebelo/metabolismo , Técnicas de Cocultivo , Células HEK293 , Humanos , Ratones Endogámicos ICR , Moléculas de Adhesión de Célula Nerviosa/genética , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Neuronas/citología , Neuronas/metabolismo , Proteínas de Unión al ARN/genética , Sinapsis/metabolismo , Ácido gamma-Aminobutírico/metabolismo
20.
Biomacromolecules ; 18(2): 535-543, 2017 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-28055201

RESUMEN

Delivery of anticancer drugs into tumor cores comprised of malignant cancer cells can result in potent therapeutic effects. However, conventional nanoparticle-based drug delivery systems used for cancer therapy often exhibit inefficient tumor-penetrating properties, thus, suggesting the need to improve the functional design of such systems. Herein, we focus on the interactions between cancer cells and the extracellular matrix (ECM) and demonstrate that liposomes modified with slightly acidic pH-sensitive peptide (SAPSp-lipo) can penetrate in vivo tumor tissue and in vitro spheroids comprised of cancer cells and ECM. We previously reported SAPSp-lipo, tumor microenvironment-sensitive liposomes, are effectively delivered to tumor tissue (Hama et al. J Control Release 2015, 206, 67-74). Compared with conventional liposomes, SAPSp-lipo could be delivered to deeper regions within both spheroids and tumor tissues. Furthermore, tumor penetration was found to be promoted at regions where actin depolymerization was induced by SAPSp-lipo and inhibited by the polymerization of actin. In addition, SAPSp-lipo attenuated the interaction between cancer cells and ECM, contributing to the penetration of SAPSp-lipo. These results suggest that SAPSp-lipo penetrates tumors via the interspace route and is accompanied by actin depolymerization. Taken together, SAPSp-lipo demonstrates potential as a novel tumor-penetrable drug carrier for induction of therapeutic effects against malignant cells that comprise tumor cores.


Asunto(s)
Actinas/metabolismo , Sistemas de Liberación de Medicamentos , Matriz Extracelular/metabolismo , Liposomas/administración & dosificación , Melanoma Experimental/tratamiento farmacológico , Nanopartículas/administración & dosificación , Fragmentos de Péptidos/farmacología , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Matriz Extracelular/efectos de los fármacos , Liposomas/química , Masculino , Melanoma Experimental/metabolismo , Ratones , Ratones Pelados , Nanopartículas/química , Fragmentos de Péptidos/administración & dosificación , Polimerizacion , Células Tumorales Cultivadas , Microambiente Tumoral
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