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1.
Prog Rehabil Med ; 7: 20220040, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991772

RESUMEN

Background: Exercise therapy for patients with pediatric nephrotic syndrome is necessary to improve physical function to maintain the patient's activities of daily life and school life while managing the risk of relapse; however, few studies have examined exercise therapy in the acute phase of the syndrome. This case study aimed to evaluate the efficacy and safety of exercise therapy in a patient with acute pediatric nephrotic syndrome being treated with steroids. Case: The patient was a 10-year-old boy diagnosed with primary nephrotic syndrome. Prednisolone (50 mg) was started on the 3rd day of hospitalization. Exercise therapy (moderate-intensity, 40 min, five times a week) was started on the 15th day. The urine protein/creatinine ratio from the 15th day (at the start of rehabilitation) to discharge decreased from 1.1  to 0.4, with no recurrence of nephrotic syndrome. At the initial, middle, and final evaluations, respectively, the grip strength was 10.1, 8.9, and 8.3 kg; the knee extension strength was 0.38, 0.46, and 0.45 kgf/kg; the sit-up test results were 18, 18, and 15 times; the side-step test results were 34, 36, and 31 times; the sit-and-reach test results were 22.9, 24.5, and 23.8 cm; and the 6-min walk test results were 420, 490, and 520 m. Leg muscle strength and exercise tolerance improved, but upper limb strength, trunk muscle strength, and agility decreased. Discussion: Moderate-intensity exercises may be effective and safe for pediatric patients with nephrotic syndrome in the acute phase. Exercise therapy may be beneficial to improve physical function and prevent decline during hospitalization in pediatric nephrotic syndrome patients.

2.
Rev Sci Instrum ; 88(1): 013706, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28147653

RESUMEN

We have developed a passive long-wavelength infrared (LWIR) scattering-type scanning near-field optical microscope (s-SNOM) installed in a helium-free mechanically cooled cryostat, which facilitates cooling of an LWIR detector and optical elements to 4.5 K. To reduce mechanical vibration propagation from a compressor unit, we have introduced a metal bellows damper and a helium gas damper. These dampers ensure the performance of the s-SNOM to be free from mechanical vibration. Furthermore, we have introduced a solid immersion lens to improve the confocal microscope performance. To demonstrate the passive s-SNOM capability, we measured thermally excited surface evanescent waves on Au/SiO2 gratings. A near-field signal-to-noise ratio is 4.5 times the improvement with an acquisition time of 1 s/pixel. These improvements have made the passive s-SNOM a more convenient and higher-performance experimental tool with a higher signal-to-noise ratio for a shorter acquisition time of 0.1 s.

3.
Pediatr Int ; 59(1): 48-52, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27507671

RESUMEN

BACKGROUND: While the association between scoliosis and cardiac and respiratory function impairments has been well characterized in clinical practice and research, the potential effect of scoliosis on urinary tract structure and renal function has received little attention. Therefore, the purpose of this study was to evaluate the preoperative clinical characteristics of urinary tract structure and renal function in pediatric patients with idiopathic scoliosis, using a combination of blood tests, urinalysis, and imaging. METHODS: Preoperative measures of urinary tract structure and renal function were obtained for 16 patients, 13-17 years old, scheduled for corrective surgery for idiopathic scoliosis. Preoperative assessment included blood test and urinalysis, combined with structural imaging on ultrasound (US), magnetic resonance imaging (MRI), magnetic resonance urography (MRU), and radioisotope tracing (RI), using technetium-99 m mercaptoacetyltriglycine (99m Tc-MAG3). Differences in blood and urine tests between patients with and without urinary tract obstruction (UTO) were evaluated for significance using Mann-Whitney U test. RESULTS: For all 16 patients, blood tests and MRU were within normal limits. Dilatation of the renal pelvis was identified on US in eight patients (50.0%). UTO was identified on RI in six patients (37.5%). UTO was associated with elevated ß2-microglobulin concentration. Urinary ß2-microglobulin concentration >0.7 µg/mg Cr differentiated patients with UTO from those without UTO, with a sensitivity of 100% and specificity of 70%. CONCLUSIONS: ß2-Microglobulin concentration may be a useful marker to screen for asymptomatic UTO in patients with idiopathic scoliosis.


Asunto(s)
Escoliosis/complicaciones , Obstrucción Ureteral/etiología , Sistema Urinario/patología , Adolescente , Biomarcadores/orina , Niño , Femenino , Humanos , Pruebas de Función Renal , Imagen por Resonancia Magnética , Masculino , Periodo Preoperatorio , Estudios Prospectivos , Escoliosis/cirugía , Tecnecio Tc 99m Mertiatida/administración & dosificación , Obstrucción Ureteral/diagnóstico por imagen , Obstrucción Ureteral/cirugía , Obstrucción Ureteral/orina , Urografía , Microglobulina beta-2/orina
4.
Nihon Koshu Eisei Zasshi ; 61(8): 371-84, 2014.
Artículo en Japonés | MEDLINE | ID: mdl-25297976

RESUMEN

OBJECTIVES: In the present study, we aimed to clarify the specific effects of age, period, and cohort on trends in obesity rate and energy intake ratio from fat in Japanese adults using a Bayesian age-period-cohort (APC) analysis and to evaluate the relationship between changes in obesity rate and energy intake ratio from fat. METHODS: We obtained data regarding obesity rate and calorie intake of fat, animal fat, carbohydrate, protein, animal protein, and total energy intake of Japanese adults from the National Nutrition Survey. The data were tabulated for five 10-year age groups (from 20-29 years to 60-69 years) and 17 annual demographic profiles (from 1995 to 2011), with regard to the energy intake ratio. These standard cohort tables were analyzed using a Bayesian APC model. RESULTS: With regard to obesity rate, the effect of age was the greatest and increased rapidly in the age group of 30-39 years for both genders. Moreover, the period effect consistently increased in men, but had very little variation in women. The cohort effect indicated a reverse of the decreasing trend in the cohorts born after 1962-1971 in men and indicated a reverse of the increasing trend in the cohorts born after 1965-1974 in women. With regard to the energy intake ratio from fat, the trends for the three effects differed from those for obesity rate for both genders. The age effect generally decreased with increasing age. Furthermore, for both genders, the period effect gradually decreased after 1998 and markedly decreased in 2001, remained constant or slightly increased until 2008, and increased thereafter. However, the cohort effect was the greatest among the three, and although a decreasing trend was observed in the cohorts born after 1976-1985 in women, the energy intake from fat increased in the younger cohorts in both genders. The overall effect on energy intake ratio from animal fat had a slope similar to that of the energy intake ratio from fat. CONCLUSION: Each effect affected obesity and energy intake ratio from fat in a different manner, suggesting that factors other than energy intake ratio from fat, such as energy expenditure, contributed to the changes in obesity rate. However, obesity risk markedly increased in the age group of 30-39 years, and younger generations had a higher energy intake ratio from fat. These results suggest that dietary guidelines, particularly the optimal intake of animal products, is needed for younger generations to prevent the development of obesity in adulthood.


Asunto(s)
Ingestión de Energía , Grasas/administración & dosificación , Obesidad/epidemiología , Adulto , Distribución por Edad , Anciano , Carbohidratos/administración & dosificación , Efecto de Cohortes , Encuestas sobre Dietas/tendencias , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Caracteres Sexuales , Factores de Tiempo , Adulto Joven
5.
Pediatr Int ; 51(5): 617-20, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19438829

RESUMEN

BACKGROUND: Measles infection can be fatal in pediatric patients with chronic renal failure or in patients who have undergone renal transplantation, both of whom are in the immunosuppressed state. The efficacy of single, live measles vaccination in preventing infection was examined. METHODS: Of 156 children with renal failure who underwent renal transplantation, the changes in antibody titer were investigated before and after renal transplantation in 125 children whose measles antibody titer could be examined, together with disease and vaccination histories. Live measles vaccine was administered to 42 children with negative antibody titer. The antibody seroconversion rate was then investigated in these children, along with rate of antibody maintenance and degree of antibody titer elevation. RESULTS: Seroconversion rate was 97.6%. Antibody titers measured on HI and EIA were 72 +/- 118 fold (HI) and 36.9 +/- 31.3 (EIA), respectively. The geometric mean of the increase in antibody titer 6 months after vaccination was 15. No side-effects of vaccination were observed in any of the children. CONCLUSIONS: Live measles vaccination of children with chronic renal failure is effective and safe, because the seroconversion rate, rate of antibody titer maintenance and degree of antibody titer elevation in children with chronic renal failure were all equivalent to those of healthy children.


Asunto(s)
Anticuerpos Antivirales/sangre , Fallo Renal Crónico/inmunología , Vacuna Antisarampión/inmunología , Virus del Sarampión/inmunología , Sarampión/inmunología , Sarampión/prevención & control , Niño , Femenino , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/cirugía , Trasplante de Riñón , Masculino , Sarampión/sangre , Vacuna Antisarampión/sangre , Vacunación
6.
Biosci Biotechnol Biochem ; 72(8): 2236-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18685190

RESUMEN

Trp-P-2(3-amino-1-methyl-5H-pyrido [4,3-b] indole) ingestion for 42 d by C3H/HeJJcl mice caused elevation of serum alanine transaminase (ALT) activity and several signs of liver injury. These alterations were not observed in mice fed the diet supplemented with 10% miso. This suggests a preventive effect of miso as to Trp-P-2 induced liver injury.


Asunto(s)
Carbolinas/toxicidad , Hepatopatías/prevención & control , Hígado/lesiones , Alimentos de Soja , Animales , Peso Corporal/efectos de los fármacos , Masculino , Ratones , Tamaño de los Órganos/efectos de los fármacos
7.
Biochim Biophys Acta ; 1782(2): 109-17, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18187051

RESUMEN

We partially characterized the transferrin-independent iron uptake (Tf-IU) of neuronal and glial cells in the previous report. In the present study, we further examined a mechanism of which glial cells protect neuronal cells against iron stress using neuron-microglia (N-MG) and neuron-astrocyte (N-AS) co-cultures. When each solely purified cell was treated with iron citrate, cell death occurred in N and MG. However, AS proliferated under the same condition. Both N-MG and N-AS co-cultures were effective in resistance to excessive iron. The total and specific Tf-IU activities of N-MG co-cultures similar to those of N did not increase in a density-dependent manner. Contrarily, the total activity of AS was extremely high and the specific activity was extremely low as a result of proliferation. Regarding of effect of co-cultures on H(2)O(2)-induced cell death, N-MG co-cultures were less effective, but N-AS co-cultures were more effective in protecting N from the oxidative stress. These results suggest that N-MG co-cultures suppress the Tf-IU and N-AS co-cultures stimulate AS proliferation to protect neuronal cells. Brain cells from aceruloplasminemia with mutations in the ceruloplasmin gene take up iron by Tf-IU. Therefore, the different mechanisms of neuronal cell protection by MG and AS may explain the pathophysiological observations in the brains of patient with aceruloplasminemia.


Asunto(s)
Astrocitos/fisiología , Ceruloplasmina/deficiencia , Microglía/fisiología , Degeneración Nerviosa/prevención & control , Enfermedades Neurodegenerativas/etiología , Neuronas/fisiología , Estrés Oxidativo/fisiología , Animales , Animales Recién Nacidos , Muerte Celular , Células Cultivadas , Ceruloplasmina/genética , Técnicas de Cocultivo , Citoprotección/fisiología , Embrión de Mamíferos , Hierro/efectos adversos , Hierro/metabolismo , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/patología , Neuronas/metabolismo , Neuronas/patología , Ratas
8.
Carcinogenesis ; 26(10): 1821-8, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15917305

RESUMEN

3-Nitrobenzanthrone (3-NBA) has been isolated from diesel exhaust and airborne particles and identified as a potent direct-acting mutagen in vitro and genotoxic agent in vivo. In order to evaluate the in vivo toxicity and carcinogenicity of 3-NBA in a situation corresponding to inhalation, a combined short-term and lifetime study with intratracheal (i.t.) instillation in female F344 rats was performed. DNA adduct formation, as a marker for the primary effect and analyzed by 32P-HPLC after single instillation, showed a few major DNA adducts and a rapid increase with a peak after 2 days, followed by a decline. No DNA adducts above the background level were observed after 16 days. The highest DNA adduct formation was observed in lung [approximately 250 DNA adducts/10(8) normal nucleotides (NN)] closely followed by kidney (approximately 200 DNA adducts/10(8) NN), whereas liver contained only 12% (approximately 30 DNA adducts/10(8) NN) of the levels of DNA adducts found in lung. In the tumor study, squamous cell carcinomas were found after 7-9 months in the high-dose group (total dose of 2.5 mg 3-NBA) and after 10-12 months in the low-dose group (total dose of 1.5 mg 3-NBA). The fraction of squamous cell carcinoma out of the total amount of tumors observed at the end of experiment at 18 months, corresponded to 3/16 and 11/16 in the low- and high-dose group, respectively. A single case of adenocarcinoma was also observed in each group. In the control group, no tumors were observed during the entire study of 18 months. In addition, a few cases of squamous metaplasia were also observed in the lung in both dose groups but not in the controls. In conclusion, 3-NBA forms DNA adducts in the lung immediately after i.t. administration but almost all DNA adducts were eliminated after 16 days. Tumor formation in two dose groups was observed in a dose-dependent manner with squamous cell carcinomas as the predominant tumor type at high exposure.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Benzo(a)Antracenos/toxicidad , Aductos de ADN/efectos de los fármacos , Contaminantes Atmosféricos/farmacocinética , Animales , Benzo(a)Antracenos/farmacocinética , Aductos de ADN/aislamiento & purificación , Femenino , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Pulmón/efectos de los fármacos , Ratas , Ratas Endogámicas F344
9.
Pediatr Nephrol ; 17(11): 950-3, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12432440

RESUMEN

We evaluated the prevalence of white coat (WC) effect in pediatric age patients and that of white coat hypertension (WCH) in hypertensive pediatric patients. Two hundred and six patients (136 normotensive and 70 hypertensive patients, 107 boys and 99 girls, aged 6-25 years, mean 13.4, SD 4.7) were studied. Hypertension was diagnosed when systolic and/or diastolic blood pressure (BP) measurements with auscultatory technique were >or= the 95th percentile for sex and age. WC effect was defined as office BP minus daytime mean ambulatory BP (ABP). WCH was diagnosed in the hypertensive patients when daytime ABP values were < the 95th percentile for sex and height of reference values. There was a positive correlation between office BP and WC effect ( P<0.05). A WC effect of >or= 10 mmHg was observed more frequently in hypertensive patients (50%) than in normotensive patients (25%). Among 70 hypertensive patients, 33 (47%) had WCH. There was no significant difference in the prevalence of WCH in relation to age, gender, or the presence or absence of causes of hypertension. In conclusion, WC effect is frequently seen in pediatric patients, and is more common in subjects with higher office BP.


Asunto(s)
Hipertensión/diagnóstico , Hipertensión/psicología , Adolescente , Adulto , Factores de Edad , Monitoreo Ambulatorio de la Presión Arterial , Niño , Femenino , Humanos , Hipertensión/epidemiología , Masculino , Valores de Referencia , Factores Sexuales
10.
Br J Haematol ; 118(2): 638-45, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12139759

RESUMEN

Taxol is an effective anti-tumour drug against a variety of tumour cells. Taxol directly induces apoptosis in addition to a G2/M cell cycle arrest. However, it remains poorly understood how Taxol induces apoptosis in tumour cells. Taxol induces the secretion of inflammatory cytokines in murine macrophages in a toll-like receptor-4 (TLR-4)-dependent manner in addition to its anti-tumour effects, but the effect of Taxol on human macrophages is controversial. In this study, we demonstrated that low doses (less than 1000 nmol/l) of Taxol induced the expression of tumour necrosis factor (TNF)-alpha in human myelomonocytic cells and that the induction of TNF-alpha mRNA was inhibited by dominant-negative myeloid differentiation protein (dnMyD88). Furthermore, we demonstrated that the same doses of Taxol induced apoptosis of the same myelomonocytic cells and that the Taxol-induced apoptosis was also inhibited by dnMyD88. In accordance with the previous reports, Taxol induced the expression of TNF-alpha and apoptosis in a TLR4-independent manner. These results suggest that TNF-alpha expression and apoptosis, both induced by Taxol in human myelomonocytic cells, share the signal transduction molecule MyD88.


Asunto(s)
Antígenos de Diferenciación/metabolismo , Antineoplásicos Fitogénicos/farmacología , Células de la Médula Ósea/citología , Monocitos/citología , Paclitaxel/farmacología , Receptores Inmunológicos/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Apoptosis/efectos de los fármacos , Comunicación Celular , Granuloma/metabolismo , Granuloma/patología , Humanos , Factor 88 de Diferenciación Mieloide , ARN Mensajero/metabolismo , Transducción de Señal , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Células Tumorales Cultivadas
11.
Yakugaku Zasshi ; 122(2): 157-62, 2002 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-11857956

RESUMEN

In an attempt to achieve chronopharmacotherapy for asthma, press-coated tablets (250 mg), which contained aminophylline in the core tablet in the form of low-substituted hydroxypropylcellulose (L-HPC) and coated with crystalline cellulose (PH-102) and polyethylene glycol (PEG) at various molecular weights and mixing ratios in the amounts of PH-102 and PEG as the outer shell (press-coating material), were prepared (chronopharmaceutics). Their applicability as timed-release (delayed-release) tablets with a lag time of disintegration and a subsequent rapid drug release phase was investigated. Various types of press-coated tablets were prepared using a tableting machine, and their aminophylline dissolution profiles were evaluated by the JP paddle method. Tablets with the timed-release characteristics could be prepared, and the lag time of disintegration was prolonged as the molecular weight and the amount of PEG, for example PEG 500,000, in the outer shell were increased. The lag time of disintegration could be controlled by the above-mentioned method, however, the pH of the medium had no effect on disintegration of the tablet and dissolution behavior of theophylline. The press-coated tablet (core tablet:aminophylline 50 mg, L-HPC and PEG 6000; outer shell:PH-102:PEG = 8:2 200 mg) with the timed-release characteristics was administered orally to rabbits for an in vivo test. Theophylline was first detected in plasma more than 2 h after administration; thus, this tablet showed a timed-release characteristics in the gastrointestinal tract. The time (tmax) required to reach the maximum plasma theophylline concentration (Cmax) observed after administration of the press-coated tablet was significantly (p < 0.05) delayed compared with that observed after administration of aminophylline solution in the control experiment. However, there was no difference in Cmax and area under the plasma theophylline concentration-time curve (AUC0-->24) between the press-coated tablet and aminophylline solution. These results suggest that the press-coated aminophylline tablet (with the timed-release characteristic) offers a promising forms of theophylline chronotherapy for asthma.


Asunto(s)
Aminofilina , Celulosa , Polietilenglicoles , Aminofilina/farmacocinética , Animales , Asma/tratamiento farmacológico , Cronoterapia , Preparaciones de Acción Retardada , Concentración de Iones de Hidrógeno , Conejos , Solubilidad , Comprimidos Recubiertos
12.
Biochem Biophys Res Commun ; 290(1): 213-8, 2002 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-11779155

RESUMEN

Iron regulatory protein-1 (IRP-1) is known as a cytosolic aconitase and a central regulator of iron (Fe) homeostasis. IRP-1 regulates the expression of Fe metabolism-related proteins by interacting with the Fe-responsive element (IRE) in the untranslated regions of mRNAs of these proteins. However, it is less known whether IRP-1 modulates various non-Fe metals. In the present study, we showed that treatment of homogenously purified IRP-1 with non-Fe metals decreased the affinity to IRE in RNA band shift assays and increased aconitase activity. Non-Fe metals also inhibited (55)Fe incorporation into the fourth labile position of the Fe-S cluster of IRP-1. In PLC hepatoma cells, metal loading inactivated binding activity and activated enzyme activity. It also suppressed transferrin receptor mRNA expression in the cells. These results suggest that various non-Fe metals modulate IRP-1 by conversion of the 3Fe-4S apo-form to a [1 non-Fe metal + 3Fe]-4Fe holo-form.


Asunto(s)
Proteínas Hierro-Azufre/metabolismo , Hierro/metabolismo , Metales/farmacología , Proteínas de Unión al ARN/metabolismo , Aconitato Hidratasa/metabolismo , Animales , Unión Competitiva , Northern Blotting , Cadmio/farmacología , Carcinoma Hepatocelular/metabolismo , Bovinos , Quelantes/farmacología , Cobre/farmacología , Relación Dosis-Respuesta a Droga , Ácido Edético/farmacología , Humanos , Proteína 1 Reguladora de Hierro , Proteínas Reguladoras del Hierro , Cinética , Hígado/metabolismo , Manganeso/farmacología , Mercurio/farmacología , Níquel/farmacología , Unión Proteica , ARN Mensajero/metabolismo , Receptores de Transferrina/metabolismo , Células Tumorales Cultivadas
13.
J Nanosci Nanotechnol ; 2(3-4): 321-3, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12908258

RESUMEN

Fine-pitched microgratings are encoded on fused silica surfaces by a two-beam laser interference technique employing UV femtosecond pulses from the third harmonics of a Ti:sapphire laser. A pump and prove method utilizing a laser-induced optical Kerr effect or transient optical absorption change has been developed to achieve the time coincidence of the two pulses. Use of the UV pulses makes it possible to narrow the grating pitches to an opening as small as 290 nm, and the groove width of the gratings is of nanoscale size. The present technique provides a novel opportunity for the fabrication of periodic nanoscale structures in various materials.


Asunto(s)
Calor , Interferometría/métodos , Rayos Láser , Nanotecnología/métodos , Dióxido de Silicio/efectos de la radiación , Interferometría/instrumentación , Nanotecnología/instrumentación , Dióxido de Silicio/química , Propiedades de Superficie , Rayos Ultravioleta
14.
Dev Growth Differ ; 34(4): 427-435, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37281818

RESUMEN

Although the spindle body of the grasshopper neuroblasts at the early mitotic stages does not have any mechanical linkage to the surrounding cell cortex, a spindle axis is inevitably oriented in parallel with the original division axis. The present study analyzes how the definite orientation of spindle axis along the cap cell (CC)-ganglion cell (GC) axis of the neuroblast is maintained during these stages by use of the microdissection technique and electron microscopy. After removing a microneedle from the cell, metaphase spindles approximately 90°. rotated were able to return autonomously to the original axis. After the middle anaphase, however, the rotated spindle could not return at all. The electron microscopic observations revealed a characteristic behavior of an electron dense layer (EDL) in the CC-side cortex during neuroblast mitosis. The EDL first appeared at very late prophase and became most conspicuous at metaphase. It became discontinuous by the beginning of middle anaphase and then completely disappeared at middle anaphase. So long as an EDL existed in the CC-side polar cortex, 90° rotated spindle bodies were able to return autonomously to the original axis. After the disappearance of the EDL, the autonomous return of the rotated spindle no longer occurred. From these circumstantial evidence, it is conceivable that the orientation of the spindle body along the CC-GC axis is maintained by the interaction between the EDL and the spindle pole.

15.
Dev Growth Differ ; 28(6): 603-609, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37281061

RESUMEN

The grasshopper neuroblast divides unequally to produce two types of cells: a large daughter neuroblast that contains a doughnut-shaped nucleus and repeats unequal division with definite polarity, and a small daughter ganglion cell that has a spherical nucleus with low mitotic activity. Binucleate neuroblasts were induced by preventing cytokinesis in the course of microdissection experiments, and subsequent divisions were traced to analyze the factors that determine the polarity of unequal division. In binucleate neuroblasts, both daughter chromosome groups developed into neuroblast-type nuclei. Mitosis of the two nuclei proceeded synchronously. Although the axes of the two mitotic apparatuses formed at late prophase were random in direction, they became parallel with the original division axis at metaphase. The two mitotic apparatuses shifted simultaneously toward the ganglion cell side during anaphase, just as in normal neuroblasts, and the binucleate cell divided unequally. These findings showed that the poearity of unequal division is strictly maintained in grasshpper neuroblasts, even when they contain two nuclei.

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