Combination of super chilling and high carbon dioxide concentration techniques most effectively to preserve freshness of shell eggs during long-term storage.

This study was made to examine the combined effects of stored temperature and carbon dioxide atmosphere on shell egg quality. The shell eggs were packed into polyethylene terephthalate/polyethylene (PET/PE) pouches and stored at 0 degrees C (super chilling), 10 degrees C, and 20 degrees C, respectively for 90 d. The atmospheric carbon dioxide concentration was controlled to obtain the 3 concentration levels of high (about 2.0%), medium (about 0.5%), and low (below 0.01%). Changes in Haugh unit (HU) values, weakening of vitelline membranes, and generation of volatiles were analyzed to evaluate the freshness of shell eggs. Results showed that, compared with the other combinations, the technique of super chilling and high carbon dioxide concentration enabled shell eggs to be most effectively stored for 90 d, based on estimations of the statistical significances of differences in HU values, and on maintaining the initial HU values during storage. In addition, the storage of shell eggs using this combination technique was found to significantly prevent the weakening of the vitelline membrane based on the estimations of numbers of eggs without vitelline membrane breakage when eggs broke, and significantly lowered the incidence of hexanal in the yolk from exposure to the gas chromatographic-mass spectrometric analyses of volatiles. Thus, these results confirmed that the combination of super chilling and high carbon dioxide concentration was the most effective technique for preserving shell eggs during a long term of 90 d compared with other combination techniques.

Significance of metaphase II human oocyte morphology on ICSI outcome.

OBJECTIVE: To evaluate the influence of specific oocyte morphologic features (morphotypes) on intracytoplasmic sperm injection (ICSI) outcome. The identification of oocyte quality markers is particularly important when a low number of oocytes can be used for IVF. DESIGN: Retrospective analysis. SETTING: Medical center. PATIENT(S): Five hundred sixteen consecutive ICSI cycles. Only couples affected by severe male factor infertility were excluded. INTERVENTION(S): A total of 1,191 metaphase II (MII) oocytes (1-3 per patient) were randomly selected from the cohort of oocytes obtained from each patient and evaluated for morphologic appearance. MAIN OUTCOME MEASURE(S): Fertilization, pronuclear morphology, embryo quality, pregnancy rate. RESULT(S): There was a presence of vacuoles, abnormal I polar body, and large perivitelline space related to a lower fertilization rate. Pronuclear morphology was effected by the presence of a large perivitelline space, diffused cytoplasmic granularity, and/or centrally located granular area. The latter characteristic also negatively related to day 2 embryo quality. According to the odds ratios obtained for each oocyte morphotype to reach at least one outcome, an MII oocyte morphologic score (MOMS) was calculated. A significant relationship was found between MOMS and female age, female basal FSH, and clinical outcome. CONCLUSION(S): Morphologic evaluation before ICSI helps to identify MII oocytes with higher developmental potential.

Vascular abnormalities and elevated blood pressure in mice lacking adrenomedullin gene.

BACKGROUND: Adrenomedullin (AM) is a vasodilating peptide involved in the regulation of circulatory homeostasis and in the pathophysiology of certain cardiovascular diseases. Levels of AM are markedly increased in the fetoplacental circulation during pregnancy, although its function there remains unknown. To clarify the physiological functions of AM, we chose a gene-targeting strategy in mice. METHODS AND RESULTS: Targeted null mutation of the AM gene is lethal in utero: the mortality rate among AM(-/-) embryos was >80% at E13.5. The most apparent abnormality in surviving AM(-/-) embryos at E13.5 to E14.0 was severe hemorrhage, readily observable under the skin and in visceral organs. Hemorrhage was not detectable at E12.5 to E13.0, although the yolk sac lacked well-developed vessels. Electron microscopic examination showed endothelial cells to be partially detached from the basement structure at E12.5 in vitelline vessels and hepatic capillaries, which allowed efflux of protoerythrocytes through the disrupted barrier. The basement membrane was not clearly recognizable in the aorta and cervical artery, and the endothelial cells stood out from the wall of the lumen, only partially adhering to the basement structure. AM(+/-) mice survived to adulthood but exhibited elevated blood pressures with diminished nitric oxide production. CONCLUSIONS: AM is indispensable for the vascular morphogenesis during embryonic development and for postnatal regulation of blood pressure by stimulating nitric oxide production.

Tumor do saco vitelino testicular: estudo microcópico de 15 casos / Testicular yolk sac tumor: microscopic study of 15 cases

Os tumores de células germinativas såo as neoplasias mais comuns do testículo, correspondendo a mais de 95 por cento das neoplasias desse órgäo, sendo o tumor de saco vitelino o mais recentemente reconhecido. Em crinças, o tumor do saco vitelino é encontrado na forma pura e, em adultos, está quase que invariavelmente associado a outros tipos de tumores de células germinativas. É uma neoplasia com diversos aspectos microscópicos distintos e ainda pouco reconhecidos. Os autores revisaram 15 casos de tumores de testículo com componente de tumor de saco vitelino e observaram a distribuiçåo por várias faixas etárias, a presença de outros tipos histológicos de tumores de células germinativas associados e analisaram seus vários aspectos microscópicos. Concluem que a presença do aspecto microscópio peculiar de seio endodérmico näo é imprescindível para o diagnóstico de tumor do saco vitelino, porque está presente em menos de 3/4 dos casos (73,3 por cento). O aspecto que mais auxilia no diagnóstico desse tumor é o reticular (ou microcístico), o qual é o mais freqüentemente observado (93,3 por cento)

[A colonic structure in the placenta: a simple teratoma coaetans or ectopic differentiation?]. / Une structure colique à localisation placentaire: teratome coaetans simplifié ou différenciation ectopique?

A cylindrical structure which was closed on either side and covered by the amnion was found in a placenta. Histological examination showed well differentiated wall of large intestine with sympathetic plexus. Several hypothesis are discussed: teratoma, fetus acardiacus amorphus, anomalous differentiation of the yolk sac.

Histologic analyses of experimental tumors from mouse blastocyst-derived cell lines.

Previous work has shown that established cell lines can be derived from cultured mouse blastocysts. Although these cell lines differed from one another morphologically, immunologically, and biochemically, it has not been easy to determine what embryonic cell type (if any) each cell line represents. We showed in this report that these blastocyst-derived lines could produce tumors in syngeneic mice at low yields and presented the results of histologic analyses of the tumors which we carried out to learn more about the kinds of cells present in each of the lines. Tumors derived from cell line MB2 contained two kinds of cells. Most of the cells were similar to those found in so-called "parietal yolk sac carcinomas," secreted Reichert's membrane-like material, and could be found in subsequent transplant generations. The other cell type resembled trophoblast giant cells morphologically and did not survive transplantation. These results showed that MB2 contained cells which were either parietal endoderm cells or a closely related precursor. The tumor derived from MB4 consisted of small, closely packed cells intermixed with larger cells with foamy cytoplasm and occasional giant cells. Cells in subsequent passages of the tumor were often organized into acinar clusters. Biochemical evidence has suggested that MB4 cells resembled one or both components of visceral yolk sac. Visceral yolk sac sarcomas have not previously been reported; the MB4-derived tumor may prove to be the first. Tumors derived from line MB31 contained both fibroblastic and epithelioid cell types which could not be more definitively identified. Cultures derived from each kind of tumor in each case contained cells morphologically characteristic of those in the originally inoculated population. Our results showed that tumors produced from blastocyst-derived cell lines did not resemble the teratocarcinomas which formed when blastocysts were implanted into an ectopic site in vivo: They did not contain a wide variety of cell types, nor did they possess pluripotent embryonal carcinoma "stem" cells characteristic of the teratocarcinoma. That each blastocyst-derived line gave rise to a different kind of tumor suggested that each line may have been made up of cells "trapped" at some stage characteristic of the development of a particular embryonic or extraembryonic tissue. However, each tumor did contain at least two distinct cell types; this suggested that cells in the blastocyst-derived lines, though restricted to their developmental potential, may not yet have been completely determined.

[Vitelline components in teratomas and serum alpha-1 fetoprotein]. / Composante vitelline des tératomes et alpha1-foetoprotéine sérique

Serum alpha1-fetoprotein (AFP) had been determined in 31 patient with (mostly malignant) teratomas before or immediately after operation, and later in the evolution of 3 other cases with clinical evidence of recurrence or metastases. Without knowledge of these serum AFP levels, histological slides of the same 34 teratomas were reexamined, especially for the presence of yolk sac components. Two pure yolk sac tumors and 6 teratomas containing yolk sac structures were associated with serum AFP levels above 500 ng/ml. Teratomas without yolk sac structures were associated with normal serum AFP levels (i.e. 10-500 ng/ml) in 14 cases, and high serum levels (i.e. above 500 ng/ml) in one case. Histologic analysis of the 14 cases with slightly elevated AFP levels did not reveal tissue possibly responsible for the low but nevertheless abnormal AFP synthesis. High AFP levels, which are easily detectable by counter-current immunoelectrophoresis, are, however, highly specific for the yolk sac tumor or the yolk sac component of teratomas, and hence suggest that this extra-embryonic structure should be distinguished from other teratoma components.