427 research outputs found
Top-Down Impacts of Sea Nettles (Chrysaora quinquecirrha) on Pelagic Community Structure in Barnegat Bay, New Jersey, U.S.A.
Coastal communities are substantially affected by human activities and create environments conducive to opportunistic species and structural changes in food webs. The Mid-Atlantic coast of the United States is highly urbanized with significant landscape modification and elevated pollutant loads. The appearance and development of resident populations of the Atlantic sea nettle (Chrysaora quinquecirrha) in Barnegat Bay, New Jersey demonstrates a successful establishment to this estuary. This research indicates that two species of gelatinous zooplankton (Mnemiopsis leidyi, C. quinquecirrha) play important structuring roles in the pelagic community. Specifically, M. leidyi exerts significant top-down control of calanoid copepods, cladocerans, fish eggs, and fish larvae, whereas C. quinquecirrha’s impact is felt through control of M. leidyi, whose density is two orders of magnitude greater. It was expected that if C. quinquecirrha exerted top-down control of M. leidyi, then a trophic cascade would result. However, no trophic cascade was observed, as C. quinquecirrha demonstrated broad control of pelagic community structure as a nonspecific, generalist predator. Consequently, the strength of M. leidyi’s ability to exert predation pressure is mediated by the development of the C. quinquecirrha bloom, but pelagic community structure is broadly defined by the combined impact of these predators within the system
A class of nonparametric bivariate survival function estimators for randomly censored and truncated data
This paper proposes a class of nonparametric estimators for the bivariate survival function estimation under both random truncation and random censoring. In practice, the pair of random variables under consideration may have certain parametric relationship. The proposed class of nonparametric estimators uses such parametric information via a data transformation approach and thus provides more accurate estimates than existing methods without using such information. The large sample properties of the new class of estimators and a general guidance of how to find a good data transformation are given. The proposed method is also justified via a simulation study and an application on an economic data set
A Case of Advanced Tubal Ectopic Pregnancy after Emergency Contraception
Ectopic pregnancy is a relatively common condition and an important cause of morbidity in women of childbearing age. The most frequent implantation site is the fallopian tube. Most cases are diagnosed in an early gestational period. Patients come to the attention of clinicians for pelvic pain and vaginal blood loss, and consequent diagnosis is made through clinical presentation, laboratory tests, and ultrasound. Other rarer implantation sites such as the abdominal cavity give space for ectopic pregnancy to grow until later gestational ages, delaying diagnosis. This is a rare case of a healthy 41-year-old woman with an advanced ectopic pregnancy after emergency contraception with Ulipristal Acetate. The patient went to visit for amenorrhea after taking a contraceptive. Evaluation with ultrasound demonstrated a 10 + 4 weeks’ unruptured tubal pregnancy with fetal heart rate. The patient underwent laparoscopic salpingectomy without complication. This is the first case of such an advanced ectopic pregnancy in a woman who performed emergency contraception with Ulipristal Acetate
Biotechnological Transformation of Hydrocortisone into 16α-Hydroxyprednisolone by Coupling Arthrobacter simplex and Streptomyces roseochromogenes
16α-Hydroxyprednisolone, an anti-inflammatory drug, could be potentially obtained from hydrocortisone bioconversion by combining a 1,2-dehydrogenation reaction performed by Arthrobacter simplexATCC31652 with a 16α-hydroxylation reaction by Streptomyces roseochromogenes ATCC13400. In this study we tested, for the first time, potential approaches to couple the two reactions using similar pH and temperature conditions for hydrocortisone bioconversion by the two strains. The A. simplex capability to 1,2-dehydrogenate the 16α-hydroxyhydrocortisone, the product of S. roseochromogenes transformation of hydrocortisone, and vice versa the capability of S. roseochromogenes to 16α-hydroxylate the prednisolone were assessed. Bioconversions were studied in shake flasks and strain morphology changes were observed by SEM. Whole cell experiments were set up to perform the two reactions in a sequential mode in alternate order or contemporarily at diverse temperature conditions. A. simplex catalyzed either the dehydrogenation of hydrocortisone into prednisolone efficiently or of 16α-hydroxyhydrocortisone into 16α-hydroxyprednisolone in 24 h (up to 93.9%). Surprisingly S. roseochromogenes partially converted prednisolone back to hydrocortisone. A 68.8% maximum of 16α-hydroxyprednisolone was obtained in 120-h bioconversion by coupling whole cells of the two strains at pH 6.0 and 26 °C. High bioconversion of hydrocortisone into 16α-hydroxyprednisolone was obtained for the first time by coupling A. simplex and S. roseochromogenes
Postoperative streptococcus constellatus bacteremia in a 75-year-old patient with pyometra: A case report
Background: Pyometra is an accumulation of pus in the uterine cavity. It is rare in the general population but more common in elderly women. If diagnosed in the early stage, life-threating conditions may be avoided. The most common etiological microorganisms of pyometra are Escherichia coli, Bacteroides species, Staphylococci (eg, epidermid-is) and Streptococci. Occasionally, atypical bacteria may be the cause. Case Report: We present the case of a 75-year-old woman, with multiple risk factors, admitted to the Gynecology Department with a 15-day history of yellowish-brown vaginal discharge. Because of rapid enlargement of the uterine cavi-ty, the patient underwent to endometrial curettage. Three hours after surgery, she developed a high-grade fe-ver, and Streptococcus constellatus was isolated in her blood cultures. A specific antibiotic therapy was admin-istered for a total of 14 days, resulting in complete resolution of the infection. Conclusions: This case report describes a rare case of bacteremia caused by Streptococcus constellatus, that resulted from a pyometra. The classic triad of symptoms (postmenopausal bleeding, vaginal discharge, and lower abdominal pain) may be helpful for diagnosis; however, 50% of patients are asymptomatic. An early recognition of the con-dition is important to avoid rare but risky consequences, such as perforation of the uterus itself. Nevertheless, surgery can cause dangerous complications such as bacteremia. A different spectrum of bacteria may be in-volved in the development of pyometra, even in atypical cases, mostly when multiple comorbidities are pres-ent. A correct evaluation and management of the patient is essential to guarantee a good prognosis in this rare infection
Towards personalized medicine: Non-coding rnas and endometrial cancer
Endometrial cancer (EC) is the most frequent female cancer associated with excellent prognosis if diagnosed at an early stage. The risk factors on which clinical staging is based are constantly updated and genetic and epigenetic characteristics have recently been emerging as prognostic markers. The evidence shows that non-coding RNAs (ncRNAs) play a fundamental role in various biological processes associated with the pathogenesis of EC and many of them also have a prognosis prediction function, of remarkable importance in defining the therapeutic and surveillance path of EC patients. Personalized medicine focuses on the continuous updating of risk factors that are identifiable early during the EC staging to tailor treatments to patients. This review aims to show a summary of the current classification systems and to encourage the integration of various risk factors, introducing the prognostic role of non-coding RNAs, to avoid aggressive therapies where not necessary and to treat and strictly monitor subjects at greater risk of relapse
Editorial: Fertility-preserving and fertility-sparing treatment approaches in gynecologic malignancies
Gene polymorphism in five target genes of immunosuppressive therapy and risk of development of preeclampsia
Pregnancy can be considered as an allogeneic transplant and preeclampsia can be seen as a failure of the acceptance mechanisms of this transplant as occurs in acute organ transplant rejection. Some genetic polymorphisms may be involved in its pathogenesis. Since the kidney is one of the organs mainly involved in preeclampsia, our study attempted to determine the frequencies of single nucleotide polymorphisms of DNA (SNP) in 3 genes (adenosine triphosphate-binding cassette sub-family B member 1 (ABCB1)/multi drug reactivity 1 (MDR1) gene, interleukin 10 gene and tumor necrosis factor \u3b1 gene) which are targets of immunosuppressive therapies and related to acute renal rejection. The study was an observational, monocentric, case-control study. We enrolled 20 women with severe preeclampsia and 10 women age-matched with regular pregnancy. Continuous variables were compared by the Student\u2019s t-test for independent variables or using the Mann-Whitney test depending on their distribution. We used Fisher test to compare categorical variables between cases and controls, while we used logistic regression model to evaluate which risk factor was associated with preeclampsia. Although there was no statistically significant difference between the two groups, we found different percentages of two of the polymorphisms considered (rs1045642 and rs2032582 in the gene ABCB1). Despite these results, our work may be helpful for future research to better understand the pathogenesis of preeclampsia
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Live Imaging of Cysteine-Cathepsin Activity Reveals Dynamics of Focal Inflammation, Angiogenesis, and Polyp Growth
It has been estimated that up to 30% of detectable polyps in patients regress spontaneously. One major challenge in the evaluation of effective therapy of cancer is the readout for tumor regression and favorable biological response to therapy. Inducible near infra-red (NIR) fluorescent probes were utilized to visualize intestinal polyps of mice hemizygous for a novel truncation of the Adenomatous Polyposis coli (APC) gene. Laser Scanning Confocal Microscopy in live mice allowed visualization of cathepsin activity in richly vascularized benign dysplastic lesions. Using biotinylated suicide inhibitors we quantified increased activities of the Cathepsin B & Z in the polyps. More than ¾ of the probe signal was localized in CD11b+Gr1+ myeloid derived suppressor cells (MDSC) and CD11b+F4/80+ macrophages infiltrating the lesions. Polyposis was attenuated through genetic ablation of cathepsin B, and suppressed by neutralization of TNFα in mice. In both cases, diminished probe signal was accounted for by loss of MDSC. Thus, in vivo NIR imaging of focal cathepsin activity reveals inflammatory reactions etiologically linked with cancer progression and is a suitable approach for monitoring response to therapy.Stem Cell and Regenerative Biolog
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