592 research outputs found

    Trophoblast 'pseudo-tumorigenesis': Significance and contributory factors

    Get PDF
    Trophoblast cells of the human placenta proliferate, migrate, and invade the pregnant uterus and its vasculature in order to nourish the developing fetus, in a way that is imitated by malignant tumors. Many similarities exist between embryo implantation and the growth of cancer cells. We begin this article by reviewing decades of studies that have helped unearth the mechanisms that contribute to the tumor-like phenotype of human trophoblast cells. Interestingly, these attributes are only transient in nature, with stringent spatial and temporal confines. The importance of intrinsic molecular controls that effectively circumscribe the extent and duration of trophoblast incursion, becomes increasingly evident in abnormal pregnancies that are characterized by aberrant trophoblast proliferation/invasion. We summarize and discuss the significance of abnormalities in these regulatory mechanisms, and finally, speculate about the use of human trophoblastic cells as model systems for the study of a variety of cellular processes. While on one hand, human placental cells are bestowed with a capacity to proliferate indefinitely and invade extensively, on the other, these cells are also replete with mechanisms to regulate these tumor-like attributes and eventually progress to a senescent apoptotic state. This is therefore, a 'well-behaved' tumor. The comparison in the present review is between the invasive cytotrophoblastic cell type and the tumor cell type

    Mean values of multiplicative functions over function fields

    Get PDF
    We discuss the mean values of multiplicative functions over function fields. In particular, we adapt the authors’ new proof of Halász’s theorem on mean values to this simpler setting. Several of the technical difficulties that arise over the integers disappear in the function field setting, which helps bring out more clearly the main ideas of the proofs over number fields. We also obtain Lipschitz estimates showing the slow variation of mean values of multiplicative functions over function fields, which display some features that are not present in the integer situation

    Investigation on physical and mechanical behaviour of A356 - x wt. % SiC/Gr hybrid composites

    Get PDF
    The experiments were planned to fabricate an A356 as a matrix material with 3, 6, 9, 12 wt. % of SiC and 3 wt. % of Gr as reinforcements to cast the hybrid composites at optimal process variable conditions using squeeze casting technique. Further T6 heat treated casted samples are prepared for testing as per standard procedure to record the responses like density, porosity, hardness, ultimate tensile strength, and percentage elongation respectively. There is a gradual increment in density because of adding an optimal level of up to 9 wt. % of SiC and 3 wt. % of Gr strengthening particles available in the A356 matrix and the porosity present in the sample diminishes, which in turn increases the hardness

    The third moment of quadratic Dirichlet L-functions

    Full text link
    We study the third moment of quadratic Dirichlet L-functions, obtaining an error term of size O(X3/4+ε)O(X^{3/4 + \varepsilon}).Comment: 27 pages. v2: modified a remark on p.

    Assessment of the functional outcome of multiple discs prolapses treated with discectomy and surgical stabilization in tertiary care hospital in Salem district

    Get PDF
    Background:  Low back pain affect up to 80% of people in the modern world at some point in their lives, creating high rates of activity limitation, work absence, impaired quality of life, and the need for medical care. To assess the functional outcome of patients with multiple discs prolapses treated with discectomy and surgical stabilization.Methods: A longitudinal study was conducted in the orthopedics department of Vinayaka missions Kirupananda Variyar medical college, Salem for two years between August 2019 and July 2020. A total of 30 patients presenting with lumbar disc herniation with radiculopathy and neurological deficits were included in the study. The diagnosis was confirmed by doing an X-ray and MRI of the lumbosacral spine. Patients were followed up for 6 months and the nature of the pain was assessed post-operatively using the Japanese orthopedic association system scoring for low back pain. It ranges from 0-15. Score 0 is the worst pain and 15 is normal.Results: The mean Japanese association score for low back pain was 7.2 before the surgical procedure and it was 12 after the procedure and the difference was found to be statistically significant. Among the postoperative complications, 4 patients developed failback syndrome and 1 patient had implant failure.Conclusios: Relief of radicular pain was associated with subjective satisfaction with the surgery among our study population, as evidenced by the decrease in radicular pain and the subjective satisfaction with the operation

    Hyaluronidase Coated Molecular Envelope Technology Nanoparticles Enhance Drug Absorption via the Subcutaneous Route

    Get PDF
    Parenteral chemotherapy is usually administered intravenously, although patient preference and health economics suggest the subcutaneous (sc) route could be an attractive alternative. However, due to the low aqueous solubility of hydrophobic drugs and injection volume limitations, the total amount of drug that can be administered in a single sc injection is frequently insufficient. We have developed hyaluronidase coated nanoparticles (NPs) that efficiently encapsulate such drugs, thus addressing both issues and allowing sufficient amounts of hydrophobic drug to be administered and absorbed effectively. CUDC-101, a poorly water-soluble multitargeted anticancer drug that simultaneously inhibits the receptor tyrosine kinases (RTKs) EGFR and HER2, as well as histone deacetylase (HDAC), was encapsulated in polymeric Molecular Envelope Technology (MET) NPs. The role of polymer chemistry, formulation parameters, and coating with hyaluronidase (HYD) on MET-CUDC-101 NP formulations was examined and optimized to yield high drug loading and colloidal stability, and, after freeze-drying, stable storage at room temperature for up to 90 days. The pharmacokinetic studies in healthy rats showed that plasma AUC0-24h after sc administration correlates tightly with formulation physical chemistry, specifically in vitro colloidal stability. Compared to uncoated NPs, the HYD-coating doubled the drug plasma exposure. In a murine A431 xenograft model, the coated HYD-MET-CUDC-101 NPs at a dose equivalent to 90 mg kg-1 CUDC-101 increased the survival time from 15 days (control animals treated with hyaluronidase alone) to 43 days. Polymer MET nanoparticles coated with hyaluronidase enabled the subcutaneous delivery of a hydrophobic drug with favorable therapeutic outcomes

    Antiobesogenic and Antiatherosclerotic Properties of Caralluma fimbriata Extract

    Get PDF
    There is evidence that the principles present in the widely consumed Indian food plant C. fimbriata extract (CFE) suppress appetite, and provide antiobesogenic and metabolic benefits. The Diet-Induced Obesity (DIO) rat model was used to investigate CFE's anorexigenic effects. Rats were randomly divided into three groups: (i) untreated control (C), (ii) control for cafeteria diet (CA), and (iii) cafeteria diet fed + CFE treated. Rats in the test group received cafeteria diet and CFE from day one onwards. CFE was administered by gavage at three doses (25, 50, 100 mg/Kg BW per day) for 90 days. The antiobesogenic effects of CFE were evaluated by monitoring changes in feed intake, body weight, serum lipid and hormonal (leptin) profiles, fat pads, and liver weight. Antiatherosclerotic effects were measured by histology. CFE induced significant and dose-dependent inhibition of food intake, with dose-related prevention of gains in body weight, liver weight, and fat pad mass. Alterations in serum lipid profiles associated with weight gain were similarly inhibited, as were the typical increases in serum leptin levels. These data substantiate CFE's reported anorexigenic effects. CFE treatment also conferred protection against atherogenesis. We conclude that CFE possesses antiobesogenic and antiatherosclerotic properties
    corecore