Proliferating Cell Nuclear Antigen (PCNA) Regulates Primordial Follicle Assembly by Promoting Apoptosis of Oocytes in Fetal and Neonatal Mouse Ovaries

Primordial follicles, providing all the oocytes available to a female throughout her reproductive life, assemble in perinatal ovaries with individual oocytes surrounded by granulosa cells. In mammals including the mouse, most oocytes die by apoptosis during primordial follicle assembly, but factors that regulate oocyte death remain largely unknown. Proliferating cell nuclear antigen (PCNA), a key regulator in many essential cellular processes, was shown to be differentially expressed during these processes in mouse ovaries using 2D-PAGE and MALDI-TOF/TOF methodology. A V-shaped expression pattern of PCNA in both oocytes and somatic cells was observed during the development of fetal and neonatal mouse ovaries, decreasing from 13.5 to 18.5 dpc and increasing from 18.5 dpc to 5 dpp. This was closely correlated with the meiotic prophase I progression from pre-leptotene to pachytene and from pachytene to diplotene when primordial follicles started to assemble. Inhibition of the increase of PCNA expression by RNA interference in cultured 18.5 dpc mouse ovaries strikingly reduced the apoptosis of oocytes, accompanied by down-regulation of known pro-apoptotic genes, e.g. Bax, caspase-3, and TNFα and TNFR2, and up-regulation of Bcl-2, a known anti-apoptotic gene. Moreover, reduced expression of PCNA was observed to significantly increase primordial follicle assembly, but these primordial follicles contained fewer guanulosa cells. Similar results were obtained after down-regulation by RNA interference of Ing1b, a PCNA-binding protein in the UV-induced apoptosis regulation. Thus, our results demonstrate that PCNA regulates primordial follicle assembly by promoting apoptosis of oocytes in fetal and neonatal mouse ovaries

Spectral analysis of noise in the neonatal intensive care unit

Objective To perform spectral analysis of noise generated by equipments and activities in a level III neonatal intensive care unit (NICU) and measure the real time sequential hourly noise levels over a 15 day period. Methods Noise generated in the NICU by individual equipments and activities were recorded with a digital spectral sound analyzer to perform spectral analysis over 0.5–8 KHz. Sequential hourly noise level measurements in all the rooms of the NICU were done for 15 days using a digital sound pressure level meter. Independent sample t test and one way ANOVA were used to examine the statistical significance of the results. The study has a 90% power to detect at least 4 dB differences from the recommended maximum of 50 dB with 95 % confidence. Results The mean noise levels in the ventilator room and stable room were 19.99 dB (A) sound pressure level (SPL) and 11.81 dB (A) SPL higher than the maximum recommended of 50 dB (A) respectively (p < 0.001). The equipments generated 19.11 dB SPL higher than the recommended norms in 1–8 KHz spectrum. The activities generated 21.49 dB SPL higher than the recommended norms in 1–8 KHz spectrum (p< 0.001). The ventilator and nebulisers produced excess noise of 8.5 dB SPL at the 0.5 KHz spectrum.Conclusion Noise level in the NICU is unacceptably high. Spectral analysis of equipment and activity noise have shown noise predominantly in the 1–8 KHz spectrum. These levels warrant immediate implementation of noise reduction protocols as a standard of care in the NICU

An approach to the cell-level diagnosis of malfunctioning events in PV panels from aerial thermal maps

This chapter presents an innovative approach to the cell-level diagnosis of malfunctioning events in photovoltaic (PV) panels from the processing of temperature maps taken from low-flying drones. The application of a detailed power balance equation allows deriving the electrical power generated or dissipated by each cell with a reasonable degree of accuracy. The method is tested by emulating the experimental temperature maps through accurate 3-D thermal simulations of the panel for some cases of interest

An approach to the cell-level diagnosis of malfunctioning events in PV panels from aerial thermal maps

This chapter presents an innovative approach to the cell-level diagnosis of malfunctioning events in photovoltaic (PV) panels from the processing of temperature maps taken from low-flying drones. The application of a detailed power balance equation allows deriving the electrical power generated or dissipated by each cell with a reasonable degree of accuracy. The method is tested by emulating the experimental temperature maps through accurate 3-D thermal simulations of the panel for some cases of interest

Impact of a participatory program to reduce noise in a Neonatal Unit Impacto de un programa participativo de reducción de ruido en una unidad neonatal Impacto de um programa participativo de redução do ruído em unidade neonatal

This study evaluated the impact of a participatory program to reduce noise in a neonatal intermediate care unit of a university hospital. A time-series quasi-experimental design was used, in which sound pressure levels were measured before and after the intervention was implemented using the Quest-400 dosimeter. Non-parametric statistical tests were used to compare noise with the level of significance fixed at 5%. Results showed significant reduction of sound pressure levels in the neonatal unit after the intervention program was implemented (p<0.0001). The average Leq before the intervention was 62.5dBA and was reduced to 58.8dBA after the intervention. A reduction of 7.1dBA in the average Lmax(from 104.8 to 87.7dBA) and of 30.6dBA in the average Lpeak(from 138.1 to 107.5dBA) was observed. The program was proven to be effective in significantly reducing noise levels in the neonatal unit, although levels were still more intense than recommended.<br>El objetivo fue evaluar el impacto de un programa participativo en la reducción del ruido ambiente en una unidad neonatal de un hospital universitario. Se utilizó delineamiento casi-experimental del tipo tiempo-serie, en el cual los niveles de presión sonora fueron mensurados antes y después de la implantación del programa de intervención, utilizando el dosímetro Quest-400. Para el análisis comparativo del ruido, se utilizaron las pruebas estadísticas no paramétricas (&#945;=0,05). Se constató reducción significativa de los niveles de presión sonora de la unidad neonatal después de la implantación del programa de intervención (p<0,0001). El Leq medio fue de 62,5dBA antes de la intervención y se redujo para 58,8dBA después de la intervención. Hubo reducción de 7,1dBA en el Lmax medio (de 104,8 para 87,7dBA) y de 30,6dBA en el Lpeak medio (de 138,1 para 107,5dBA). Se concluye que el programa fue efectivo en la reducción del nivel sonoro de la unidad neonatal, a pesar de que todavía se mantiene más intenso que lo recomendable.<br>O objetivo deste estudo foi avaliar o impacto de um programa participativo na redução do ruído ambiente em uma unidade neonatal, de um hospital universitário. Utilizou-se delineamento quase-experimental do tipo tempo-série, no qual os níveis de pressão sonora foram dimensionados antes e após a implantação do programa de intervenção, utilizando o dosímetro Quest-400. Para a análise comparativa do ruído, utilizaram-se os testes estatísticos não-paramétricos (&#945;=0,05). Constatou-se redução significativa dos níveis de pressão sonora da unidade neonatal, após a implantação do programa de intervenção (p<0,0001). O Leq médio foi de 62,5dBA antes da intervenção e reduziu para 58,8dBA após a intervenção. Houve redução de 7,1dBA no Lmax médio (de 104,8 para 87,7dBA) e de 30,6dBA no Lpeak médio (de 138,1 para 107,5dBA). Concluiu-se que o programa foi efetivo na redução do nível sonoro da unidade neonatal, embora ainda se mantenha mais intenso que o recomendável

Rescue of platinum-damaged oocytes from programmed cell death through inactivation of the p53 family signaling network

Non-proliferating oocytes within avascular regions of the ovary are exquisitely susceptible to chemotherapy. Early menopause and sterility are unintended consequences of chemotherapy, and efforts to understand the oocyte apoptotic pathway may provide new targets for mitigating this outcome. Recently, the c-Abl kinase inhibitor imatinib mesylate (imatinib) has become the focus of research as a fertoprotective drug against cisplatin. However, the mechanism by which imatinib protects oocytes is not fully understood, and reports of the drug's efficacy have been contradictory. Using in vitro culture and subrenal grafting of mouse ovaries, we demonstrated that imatinib inhibits the cisplatin-induced apoptosis of oocytes within primordial follicles. We found that, before apoptosis, cisplatin induces c-Abl and TAp73 expression in the oocyte. Oocytes undergoing apoptosis showed downregulation of TAp63 and upregulation of Bax. While imatinib was unable to block cisplatin-induced DNA damage and damage response, such as the upregulation of p53, imatinib inhibited the cisplatin-induced nuclear accumulation of c-Abl/TAp73 and the subsequent downregulation of TAp63 and upregulation of Bax, thereby abrogating oocyte cell death. Surprisingly, the conditional deletion of Trp63, but not ΔNp63, in oocytes inhibited apoptosis, as well as the accumulation of c-Abl and TAp73 caused by cisplatin. These data suggest that TAp63 is the master regulator of cisplatin-induced oocyte death. The expression kinetics of TAp63, c-Abl and TAp73 suggest that cisplatin activates TAp63-dependent expression of c-Abl and TAp73 and, in turn, the activation of TAp73 by c-Abl-induced BAX expression. Our findings indicate that imatinib protects oocytes from cisplatin-induced cell death by inhibiting c-Abl kinase, which would otherwise activate TAp73-BAX-mediated apoptosis. Thus, imatinib and other c-Abl kinase inhibitors provide an intriguing new way to halt cisplatin-induced oocyte death in early follicles and perhaps conserve the endocrine function of the ovary against chemotherapy.Cell Death and Differentiation advance online publication, 19 April 2013; doi:10.1038/cdd.2013.31

Oocyte DNA damage quality control requires consecutive interplay of CHK2 and CK1 to activate p63

The survival rate of cancer patients is steadily increasing, owing to more efficient therapies. Understanding the molecular mechanisms of chemotherapy-induced premature ovarian insufficiency (POI) could identify targets for prevention of POI. Loss of the primordial follicle reserve is the most important cause of POI, with the p53 family member p63 being responsible for DNA-damage-induced apoptosis of resting oocytes. Here, we provide the first detailed mechanistic insight into the activation of p63, a process that requires phosphorylation by both the priming kinase CHK2 and the executioner kinase CK1 in mouse primordial follicles. We further describe the structural changes induced by phosphorylation that enable p63 to adopt its active tetrameric conformation and demonstrate that previously discussed phosphorylation by c-Abl is not involved in this process. Inhibition of CK1 rescues primary oocytes from doxorubicin and cisplatin-induced apoptosis, thus uncovering a new target for the development of fertoprotective therapies