Effects of ovarian source, patient age, and menstrual cycle phase on in vitro maturation of immature human oocytes

OBJECTIVE: To determine the efficiency of in vitro maturation, expressed by nuclear maturation, of oocytes aspirated during gynecologic surgeries or collected from excised ovaries. To assess the effect of patient age and cycle phase at collection on the oocyte's ability to mature in vitro. To examine the time course of oocyte maturation in vitro. DESIGN: Nuclear maturation based on patient criteria compared. SETTING: University-based IVF program and research center. PATIENT(S): Consented patients undergoing gynecologic surgeries or patients undergoing oophorectomy. INTERVENTION(S): Oocytes were maintained in culture for 48 hours and evaluated for maturation. MAIN OUTCOME MEASURE(S): Nuclear maturation evaluated as germinal vesicle breakdown (GVBD) or progression to the metaphase II (MII) stage. RESULT(S): A significantly higher percentage of oocytes collected during the follicular phase of the menstrual cycle underwent GVBD than did oocytes collected during the luteal phase (60% versus 48%, respectively). The percentage of oocytes reaching the MII stage, from these two groups, was not different. No statistically significant differences in maturation were observed in oocytes from different ovarian sources or from patients >40 or <40 years of age. CONCLUSION(S): These data suggest that oocytes collected during the follicular phase are more likely to undergo GVBD than oocytes collected during the luteal phase. In this study, ovarian source, age, or cycle phase did not influence the final meiotic maturation of oocytes to metaphase II.     

The risk of subsequent primary carcinoma of the pancreas in patients with cutaneous malignant melanoma

BACKGROUND: Carcinoma of the pancreas is the fifth leading cancer in the U.S. and has the poorest survival rate of the major malignancies. Recent studies have reported an increased risk of carcinoma of the pancreas in malignant melanoma-prone kindreds and have suggested a link between malignant melanoma and pancreas carcinoma and mutations in the p16INK4 gene. This study evaluates the risk of carcinoma of the pancreas in a population-based cohort of patients with malignant melanoma. METHODS: The malignant melanoma patients were identified from the Surveillance, Epidemiology, and End Results (SEER) program of the National Cancer Institute. The cohort was followed within the SEER system to ascertain the occurrence of subsequent microscopically confirmed primary carcinoma of the pancreas from January 1973 through December 1993. The time of follow-up was expressed as person-years of observation. Standardized incidence ratios (SIR) and 95% confidence intervals (95% CI) were calculated. RESULTS: There were 43,781 malignant melanoma patients providing 263,528 person-years of follow-up. A nearly 2-fold increased risk of subsequent carcinoma of the pancreas in patients diagnosed with malignant melanoma before age 50 years was observed (SIR = 1.76; 95% CI = 0.80-3.34) and the greatest estimated risk occurred in young white females (SIR = 2.27; 95% CI = 0.73-5.30). CONCLUSIONS: These results provide some evidence in support of observations in recent studies that not only a family history of malignant melanoma but also malignant melanoma diagnosed at an early age may be associated with the subsequent development of carcinoma of the pancreas. Further research with larger numbers of melanoma patients is necessary to explore these potential associations.     

Antioxidant effect of two flavonoids from the bark of Ficus bengalensis Linn in hyperlipidemic rats

Two flavonoid compounds, viz. 5,7-dimethyl ether of leucopelargonidin 3-0-alpha-L rhamnoside and 5,3'-dimethyl ether of leucocyanidin 3-0-alpha-D galactosyl cellobioside obtained from the bark of F. bengalensis were evaluated for their antioxidant action in hyperlipidemic rats. The results were compared with the activity of a structurally similar flavonoid, quercetin, a known antioxidant. The Ficus compounds showed significant antioxidant effects which may be attributed to their polyphenolic nature. The methylation of two hydrozyl groups in the Ficus flavonoids might have slowed down their antioxidant action as compared to quercetin.     

CD4+ T lymphocytes migrating in three-dimensional collagen lattices lack focal adhesions and utilize beta1 integrin-independent strategies for polarization, interaction with collagen fibers and locomotion

Cell migration may depend on integrin-mediated adhesion to and deadhesion from extracellular matrix ligands. This concept, however, has not yet been confirmed for T lymphocytes migrating in three-dimensional extracellular matrices. We investigated receptor involvement in T cell migration combining a three-dimensional collagen matrix model with time-lapse videomicroscopy, computer-assisted cell tracking and confocal microscopy. In collagen lattices, the migration of CD4+ T cells (1) involved interactions with collagen fibers at the leading edge and uropod likewise, (2) occurred independently of the co-clustering of beta1, beta2, or beta3 integrins with F-actin, focal adhesion kinase, and phosphotyrosine at interactions with collagen fibers, (3) was counteracted by high-affinity beta1 integrin binding induced by antibody TS2/16; however, (4) the migration could not be blocked by a combination of adhesion-perturbing anti-beta1, -beta2, -beta3, and alpha v integrin antibodies. Integrin blocking neither affected cell polarization, interaction with fibers, beta1 integrin distribution, migration velocity, path structure, nor the number of locomoting cells in spontaneously migrating or concanavalin A-activated cells. Hence, T lymphocytes migrating in three-dimensional collagen matrices may utilize highly transient interactions with collagen fibers of low adhesivity, thereby differing from focal adhesion-dependent migration strategies employed by other cells.     

Cytomegalovirus iritis

We describe a case of focal cytomegalovirus iritis in a patient with acquired immunodeficiency syndrome (AIDS) who had CMV retinitis. The autopsy showed histologic evidence of focal iritis in the left eye. This iritis was characterized by infiltration of acute inflammatory cells mixed with cytomegalic cells, which was confirmed by CMV-specific immunohistochemical staining. The case suggested that cytomegalovirus could be a direct causative agent of infectious iritis in AIDS patients.     

Short interpregnancy intervals and the risk of adverse birth outcomes among five racial/ethnic groups in the United States

Unilateral microinjections of acetylcholine into the rat solitary tract nucleus evoked inhibitory effects in electrical activity of symmetrical portions of the diaphragm and external intercostal muscles. Administration of propranolol exerted excitatory respiratory responses. The findings suggest participation of cholin- and noradrenergic systems in inhibitory mechanisms of respiratory control. Different roles of the right and left solitary tract nuclei in their involvement in formation of efferent impulses to bilateral inspiratory muscles, are discussed.     

Cloning, expression and characterization of a gene which encodes a topoisomerase I with positive supercoiling activity in pea

We have isolated and sequenced the full length cDNA for topoisomerase I. Using degenerate primers, based on the conserved amino acid sequences of five eukaryotic topoisomerase I, a 386 bp fragment was PCR amplified using pea cDNA as template. This fragment was used as a probe to screen a pea cDNA library. Two partial cDNA clones were isolated which were truncated at the 5' end. RACE-PCR was employed to isolate the remaining portion of the gene. The total size of the gene was 3055 bp with an open reading frame of 2676 bp. The deduced structure of pea topoisomerase I contain 892 amino acids with a calculated molecular weight of 100 kDa and an estimated pI of 9.3. A comparison of the deduced amino acid sequences of the pea topo I with the other eukaryotic topoisomerases clearly suggested that they are all related. Pea topoisomerase I has been overexpressed in E. coli system and the recombinant topoisomerase purified to homogeneity. The purified protein relaxes both positive and negative supercoiled DNA in the absence of divalent cation Mg2+. In the presence of Mg2+ ions the purified enzyme introduces positive supercoils a unique property not reported in any other organism except in archaebacterial topoisomerase I. Polyclonal antibodies were raised against recombinant topoisomerase I and western blotting with sub-cellular fractions indicated the localization of this topoisomerase in pea nuclei.