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Brain midline delineates the boundary between the two cerebral hemispheres of the human brain, which plays a significant role in guiding intracranial hemorrhage surgery. Large midline shift caused by hematomas remains an inherent challenge for delineation. However, most previous methods only handle normal brains and delineate the brain midline on 2D CT images. In this study, we propose a novel hemisphere-segmented framework (HSF) for generating smooth 3D brain midline especially when large hematoma shifts the midline. Our work has four highlights. First, we propose to formulate the brain midline delineation as a 3D hemisphere segmentation task, which recognizes the midline location via enriched anatomical features. Second, we employ a distance-weighted map for midline aware loss. Third, we introduce rectificative learning for the model to handle various head poses. Finally, considering the complexity of hematomas distribution in human brain, we build a classification model to automatically identify the situation when hematoma breaks into brain ventricles and formulate a midline correction strategy to locally adjust the midline according to the location and boundary of hematomas. To our best knowledge, it is the first study focusing on delineating the brain midline on 3D CT images of hematoma patients and handling the situation of ventricle break-in. Through extensive validations on a large in-house dataset, our method outperforms state-of-the-art methods in various evaluation metrics.

Mastitis, an infection caused by Gram-positive bacteria, produces udder inflammation and oxidative injury in milk-producing mammals. Toll-like receptor 2 (TLR2) is important for host recognition of invading Gram-positive microbes. Over-expression ofWe over-expressedCompared with wild-type controls, measurements of various oxidative stress-related molecules showed thatThe results indicate that the oxidative injury in goats over-expressing

This minireview summarized our recent studies on the role of plasminogen activator (PA) and inhibitor type-1 (PAI-1) in luteolysis. We have demonstrated that (1) both tissue type and urokinase type plasminogen activators (tPA and uPA) and a plasminogen activator inhibitor type-1 (PAI-1) were present in the corpus luteum of rat and rhesus monkey; (2) decrease in progesterone production in corpus luteum was well correlated with a sharp increase in tPA (but not uPA) and PAI-1 secretion; (3) exogenous tPA decreased luteal progesterone synthesis while monoclonal antibodies increased progesterone production; (4) interferony inhibited luteal progesterone synthesis and stimulated tPA production while LH plus prolactin increased progesterone production and decreased tPA (hut not uPA) activity in cultured luteal cells; (5) increase in proteolysis in the corpus luteum was also correlated with decrease in progesterone production in mouse. These data suggest that local degradation of extracellular matrix controlled by plasminogen activator and inhibitor is involved in the processes of luteolysis.

Sertoli cells play a central role in the control and maintenance of spermatogenesis. Isolated Sertoli cells of mouse and rat testes have been shown to secrete plasminogen activator (PA) and a plasminogen activator inhibitor type-1 (PAI-1) in culture. In this study, we have investigated the hormonal regulation of PA and PAI-1 activities in cultured monkey Sertoli cells. Sertoli cells (5 x 10(5) cells/well) isolated from infant rhesus monkey testes were preincubated at 35 degrees C for 16 h in 24-well plates precoated with poly(D-lysine) (5 micrograms/cm2) in 0.5 ml McCoy's 5a medium containing 5% of fetal calf serum and further incubated for 48 h in 0.5 ml serum-free medium with or without various hormones or other compounds. PA as well as PAI-1 activities in the conditioned media were assayed by fibrin overlay and reverse fibrin autography techniques respectively. The Sertoli cells in vitro secreted only tissue-type PA (tPA), no detectable amount of urokinase-type PA (uPA) could be observed. Monkey Sertoli cells were also capable of secreting PAI-1. Immunocytochemical studies indicated that both tPA and PAI-1 positive staining localized in the Sertoli cells, spermatids and residual bodies of the seminiferous epithelium; Northern blot analysis further confirmed the presence of both tPA and PAI-1 mRNA in monkey Sertoli cells. Addition of follicle-stimulating hormone (FSH) or cyclic adenosine monophosphate (cAMP) derivatives or cAMP-generating agents and gonadotrophin-releasing hormone (GnRH) agonist or phorbol ester (PMA) to the cell culture significantly increased tPA activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac CT is emerging as a preferable modality to detect myocardial stress/rest perfusion; however the insufficient contrast of myocardium on CT image makes its segmentation difficult. In this paper, we present a point-guided modeling and deformable model-based segmentation method. This method first builds a triangular surface model of myocardium through Bézier contour fitting based on a few points selected by clinicians. Then, a deformable model-based segmentation method is developed to refine the segmentation result. The experiments on 8 cases show the accuracy of the segmentation in terms of true positive volume fraction, false positive volume fractions, and average surface distance can reach 91.0%, 0.3%, and 0.6mm, respectively. The comparison between the proposed method and a graph cut-based method is performed. The results demonstrate that this method is effective in improving the accuracy further.

Changes of plasminogen activators (PA) during different stages of development of the corpus luteum, and their possible physiological role in luteolysis were studied in rhesus monkeys. It was demonstrated for the first time that monkey corpus luteal cells not only produce PA, but that the function of the corpus luteum is also closely related to the activity of this enzyme system. Generally, the life span for a corpus luteum in monkey is approximately 14-16 days, its demise beginning thereafter. In the present study, we found that urokinase in the corpus luteum is higher on day 5 and day 10 after human chorionic gonadotrophin injection, while the tissue type (t) PA is mainly produced on day 13 when luteolysis may take place. Progesterone production remained high on day 5 and day 10 and decreased dramatically from day 13, indicating the important role of tPA but not urokinase (u) PA in suppressing luteal function. When purified tPA (but not uPA) monoclonal antibody was added to luteal cell culture to neutralize endogenously produced tPA activity, progesterone production in the cells was increased significantly. Interestingly, prolactin alone was capable of increasing PA production by luteal cells; prolactin together with luteinizing hormone, however, had a synergistic luteotrophic effect.

IPO underpricing is common and there are lots of evidence and theory for that. In this article, we compare the underpricing of the venture backed and non-venture backed IPOs in China. We discover that the venture backed IPOs in China tend to underprice more than non-venture backed their counterparts; however, the T test is insignificant which is inconsistent with Lee and Wahal's discovery in US. We are also explore the reason behind

The article is using the statistic data through regression to explain the non-stopping price increase of real estate in China. According to our research, the large increase of real estate is mostly due to the price increase of land and the over supply of money.

Granulosa cells (GCs) are the most important cells in the ovary that undergo serious changes morphologically and physiologically during the processes of follicular proliferation, differentiation, ovulation, lutenization and atresia. Oocyte (OC) directs GC proliferation and differentiation, while GCs influence OC maturation. Many ovarian factors are involved in the regulation of these processes via different molecular mechanisms and signal pathways. P38 MAPK can selectively regulate steroidogenesis in GCs controlled by FSH; Transcript factors LRH-1 and DAX-1 play an important role in this process; FSH induces GC proliferation and differentiation by stimulating PCNA and StAR expression and steroidogenesis. Activated ERK1/2 signal pathway may be involved in the FSH-regulated GC proliferation and differentiation. Therefore, GC is an ideal model for studying cell proliferation, differentiation and interaction, as well as signal transduction. This review briefly summarizes the latest data in the literature, including the results achieved in our laboratory.

Previous studies on azoospermia or oligozoospermia induced by heat stress or high doses of testosterone mainly focused on germ cell apoptosis; no data regarding their possible effect on spermatogonia mitosis are available. We have established unilateral cryptorchid and testosterone undecanoate (TU)-treated monkey models and examined expression of P16INK4a in the testis to look at its possible role in azoospermia or oligozoospermia induced by the heat stress or the TU treatment. The results showed that both heat stress and TU were capable of inducing expression of P16INK4a mainly in spermatogonia and other types of germ cells as well as Sertoli cells at the later stage of germ cell apoptosis, namely on Day 10 after operation or on Day 60 after TU injection. It is, therefore, suggested for the first time that P16INK4a protein may inhibit the spermatogonia mitosis in the testis at the later stage of the germ cell apoptosis, resulting in arrest of spermatogenesis.

The exact role of apoptosis that occurs in human placenta during the early stage of pregnancy remains unknown because of the difficulty in obtaining the intact implantation site. In this study, we used rhesus monkey as an animal model to examine apoptosis occurring in the implantation site at various stages of early pregnancy. It was shown that Fas and FasL mRNA and protein were localized in both the chorionic villi and glandular epithelium from day 15 to day 30 of pregnancy. Fas and FasL protein were also expressed in the epithelial plaque on day 15 of pregnancy. In situ 3'-end-labeling results showed that glandular epithelial cells underwent extensive apoptosis with obvious morphological degradation during the early stage of pregnancy. It was found that the cells that were 3'-end-labeled in the chorionic villi and anchoring villi were mainly localized in cytotrophoblast and cytotrophoblast column. It is therefore suggested that in primates apoptosis, which may be involved in the regulation of proliferation of trophoblast villi and degradation of epithelial plaque, as well as remodeling of the glands in the maternal decidua, may play an important role during the early stage of implantation and placentation.

Spermatogenesis needs the relatively cool environment of the scrotum in most mammals, it would be arrested when the testis was exposed to abdominal temperature. In this study, we have used a differential display PCR technique (DD-PCR) to screen temperature-related ESTs during spermatogenesis (TRS) in scrotal testes through a unilateral cryptorchid rat model after in situ analysis of testis cell DNA fragmentation. We reported here the cloning and sequencing of three such ESTs: TRS1, TRS3, and TRS4. Northern blot analysis confirmed that they were expressed specifically in scrotal testes. In situ hybridization showed that TRS1 was mainly expressed in the spermatocytes and the round spermatids in scrotal testis. Homology searches revealed that TRS1 and TRS3 were unknown cDNA sequences, and TRS4 was identical to a known EST whose function had not been reported. TRS1, TRS2, and TRS3 were first found to be temperature-related during spermatogenesis.