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1.
Gastroenterology ; 160(1): 183-192.e3, 2021 01.
Article in English | MEDLINE | ID: mdl-33011173

ABSTRACT

BACKGROUND & AIMS: Fecal microbiota transplantation (FMT) is used commonly for treatment of Clostridioides difficile infections (CDIs), although prospective safety data are limited and real-world FMT practice and outcomes are not well described. The FMT National Registry was designed to assess FMT methods and both safety and effectiveness outcomes from North American FMT providers. METHODS: Patients undergoing FMT in clinical practices across North America were eligible. Participating investigators enter de-identified data into an online platform, including FMT protocol, baseline patient characteristics, CDI cure and recurrence, and short and long-term safety outcomes. RESULTS: Of the first 259 participants enrolled at 20 sites, 222 had completed short-term follow-up at 1 month and 123 had follow-up to 6 months; 171 (66%) were female. All FMTs were done for CDI and 249 (96%) used an unknown donor (eg, stool bank). One-month cure occurred in 200 patients (90%); of these, 197 (98%) received only 1 FMT. Among 112 patients with initial cure who were followed to 6 months, 4 (4%) had CDI recurrence. Severe symptoms reported within 1-month of FMT included diarrhea (n = 5 [2%]) and abdominal pain (n = 4 [2%]); 3 patients (1%) had hospitalizations possibly related to FMT. At 6 months, new diagnoses of irritable bowel syndrome were made in 2 patients (1%) and inflammatory bowel disease in 2 patients (1%). CONCLUSIONS: This prospective real-world study demonstrated high effectiveness of FMT for CDI with a good safety profile. Assessment of new conditions at long-term follow-up is planned as this registry grows and will be important for determining the full safety profile of FMT.


Subject(s)
Clostridium Infections/therapy , Fecal Microbiota Transplantation , Inflammatory Bowel Diseases/therapy , Irritable Bowel Syndrome/therapy , Registries , Adolescent , Adult , Clostridioides difficile , Humans , Middle Aged , Prospective Studies , Treatment Outcome , United States , Young Adult
3.
Biol Reprod ; 87(1): 11, 1-12, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22539682

ABSTRACT

Meiosis in mammalian females is marked by two arrest points, at prophase I and metaphase II, which must be tightly regulated in order to produce a haploid gamete at the time of fertilization. The transition metal zinc has emerged as a necessary and dynamic regulator of the establishment, maintenance, and exit from metaphase II arrest, but the roles of zinc during prophase I arrest are largely unknown. In this study, we investigate the mechanisms of zinc regulation during the first meiotic arrest. Disrupting zinc availability in the prophase I arrested oocyte by treatment with the heavy metal chelator N,N,N',N'-tetrakis-(2-pyridylmethyl)-ethylenediamine (TPEN) causes meiotic resumption even in the presence of pharmacological inhibitors of meiosis. We further show that the MOS-MAPK pathway mediates zinc-dependent prophase I arrest, as the pathway prematurely activates during TPEN-induced meiotic resumption. Conversely, inhibition of the MOS-MAPK pathway maintains prophase I arrest. While prolonged zinc insufficiency ultimately results in telophase I arrest, early and transient exposure of oocytes to TPEN is sufficient to induce meiotic resumption and bypass the telophase I block, allowing the formation of developmentally competent eggs upon parthenogenetic activation. These results establish zinc as a crucial regulator of meiosis throughout the entirety of oocyte maturation, including the maintenance of and release from the first and second meiotic arrest points.


Subject(s)
Meiotic Prophase I/physiology , Oocytes/cytology , Oocytes/metabolism , Zinc/metabolism , Animals , Cell Cycle Checkpoints/drug effects , Cell Cycle Checkpoints/physiology , Chelating Agents/pharmacology , Ethylenediamines/pharmacology , Female , In Vitro Techniques , MAP Kinase Signaling System , Meiotic Prophase I/drug effects , Mice , Oocytes/drug effects , Oogenesis/drug effects , Oogenesis/physiology , Parthenogenesis , Protein Synthesis Inhibitors/pharmacology , Proto-Oncogene Proteins c-mos/metabolism , Telophase/drug effects , Telophase/physiology , Zinc/deficiency
4.
Biol Reprod ; 86(4): 114, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22302686

ABSTRACT

Precise coordination of meiotic progression is a critical determinant of an egg's capacity to be fertilized successfully, and zinc has emerged as a key regulatory element in this process. An early manifestation of a regulatory role for this transition metal is the significant increase in total intracellular zinc. This accumulation is essential for meiotic progression beyond telophase I and the establishment of meiotic arrest at metaphase II. The subsequent developmental event, fertilization, induces a rapid expulsion of labile zinc that is a hallmark event in meiotic resumption. In the present study, we show that the zinc fluxes work, in part, by altering the activity of the cytostatic factor (CSF), the cellular activity required for the establishment and maintenance of metaphase II arrest in the mature, unfertilized egg. We propose a model in which zinc exerts concentration-dependent regulation of meiosis through the CSF component EMI2, a zinc-binding protein. Together, the data support the conclusion that zinc itself, through its interaction with EMI2, is a central component of the CSF.


Subject(s)
Cell Cycle Checkpoints/physiology , F-Box Proteins/physiology , Meiosis/physiology , Oocytes/cytology , Proto-Oncogene Proteins c-mos/physiology , Zinc/physiology , Animals , Cell Cycle Checkpoints/drug effects , Chelating Agents/pharmacology , Ethylenediamines/pharmacology , F-Box Proteins/drug effects , Female , Meiosis/drug effects , Mice , Oocytes/chemistry , Oocytes/drug effects , Proto-Oncogene Proteins c-mos/drug effects , Zinc/deficiency
5.
US Obstet Gynecol ; 6(1): 24-34, 2011 Jan 01.
Article in English | MEDLINE | ID: mdl-21927621

ABSTRACT

Facing a cancer diagnosis at any age is devastating. However, young cancer patients have the added burden that life-preserving cancer treatments, including surgery, chemotherapy, and radiotherapy, may compromise their future fertility. The possibility of reproductive dysfunction as a consequence of cancer treatment has a negative impact on the quality of life of cancer survivors. The field of oncofertility, which merges the clinical specialties of oncology and reproductive endocrinology, was developed to explore and expand fertility preservation options and to better manage the reproductive status of cancer patients. Fertility preservation for females has proved to be a particular challenge because mature female gametes are rare and difficult to acquire. The purpose of this article is to provide the gynecologist with a comprehensive overview of how cancer treatments affect the female reproductive axis, delineate the diverse fertility preservation options that are currently available or being developed for young women, and describe current measures of ovarian reserve that can be used pre- and post-cancer treatment. As a primary care provider, the gynecologist will likely interact with patients throughout the cancer care continuum. Thus, the gynecologist is in a unique position to join the oncofertility team in providing young cancer patients with up-to-date fertility preservation information and referrals to specialists.

6.
ACS Chem Biol ; 6(7): 716-23, 2011 Jul 15.
Article in English | MEDLINE | ID: mdl-21526836

ABSTRACT

In last few hours of maturation, the mouse oocyte takes up over twenty billion zinc atoms and arrests after the first meiotic division, until fertilization or pharmacological intervention stimulates cell cycle progression toward a new embryo. Using chemical and physical probes, we show that fertilization of the mature, zinc-enriched egg triggers the ejection of zinc into the extracellular milieu in a series of coordinated events termed zinc sparks. These events immediately follow the well-established series of calcium oscillations within the activated egg and are evolutionarily conserved in several mammalian species, including rodents and nonhuman primates. Functionally, the zinc sparks mediate a decrease in intracellular zinc content that is necessary for continued cell cycle progression, as increasing zinc levels within the activated egg results in the reestablishment of cell cycle arrest at metaphase. The mammalian egg thus uses a zinc-dependent switch mechanism to toggle between metaphase arrest and resumption of the meiotic cell cycle at the initiation of embryonic development.


Subject(s)
Cell Cycle/physiology , Ovum/cytology , Zinc/metabolism , Animals , Calcium Signaling , Female , Fertilization in Vitro , Macaca fascicularis , Macaca mulatta , Male , Mammals/metabolism , Meiosis , Metaphase/physiology , Mice , Mice, Inbred Strains , Oocytes/cytology , Oocytes/physiology , Ovum/physiology , Parthenogenesis
7.
Biol Reprod ; 84(3): 526-36, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21076080

ABSTRACT

Zinc is essential for many biological processes, including proper functioning of gametes. We recently reported that zinc levels rise by over 50% during oocyte maturation and that attenuation of zinc availability during this period could be achieved using the membrane-permeable heavy metal chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN). This zinc insufficiency resulted in formation of large polar bodies, failure to establish metaphase II arrest, and impaired establishment of cortical polarity. As these phenotypes resemble those of MOS null oocytes, we examined the impact of zinc insufficiency on the MOS-MAPK pathway. Reduced levels of both MOS protein and phosphorylation of MAP2K1/2 are observed in zinc-insufficient oocytes; however, these differences appear only after completion of the first meiotic division. In addition, activation of the downstream effector of the MOS pathway, MAPK3/1, is not affected by zinc insufficiency, and reduced MOS levels are observed only with the presence of TPEN after the first polar body extrusion. These data are inconsistent with the hypothesis that reduced MOS mediates the observed phenotype. Finally, MOS overexpression does not rescue the phenotype of zinc-insufficient oocytes, confirming that the observed disruption of asymmetric division and spindle abnormalities cannot be attributed to impaired MOS signaling. Zinc-insufficient oocytes do not increase maturation promoting factor (MPF) activity following the first meiotic division, and increasing MPF activity through expression of nondegradable cyclin B1 partially rescues the ability of zinc-insufficient oocytes to enter metaphase II. Although we have shown that zinc has a novel role in the meiotic cell cycle, it is not mediated through the MOS-MAPK pathway.


Subject(s)
Cell Division , MAP Kinase Signaling System/physiology , Meiosis , Oocytes/cytology , Proto-Oncogene Proteins c-mos/physiology , Zinc/physiology , Actin Capping Proteins/metabolism , Animals , Cell Division/drug effects , Cell Division/genetics , Cell Division/physiology , Chromatin/physiology , Female , MAP Kinase Signaling System/drug effects , Meiosis/drug effects , Meiosis/genetics , Meiosis/physiology , Mesothelin , Mice , Models, Biological , Oocytes/drug effects , Oocytes/metabolism , Oogenesis/drug effects , Oogenesis/physiology , Phosphorylation , Proto-Oncogene Proteins c-mos/metabolism , Signal Transduction/drug effects , Signal Transduction/physiology , Zinc/deficiency , Zinc/metabolism , Zinc/pharmacology
8.
Nat Chem Biol ; 6(9): 674-81, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20693991

ABSTRACT

Cellular metal ion fluxes are known in alkali and alkaline earth metals but are not well documented in transition metals. Here we describe major changes in the zinc physiology of the mammalian oocyte as it matures and initiates embryonic development. Single-cell elemental analysis of mouse oocytes by synchrotron-based X-ray fluorescence microscopy (XFM) revealed a 50% increase in total zinc content within the 12-14-h period of meiotic maturation. Perturbation of zinc homeostasis with a cell-permeable small-molecule chelator blocked meiotic progression past telophase I. Zinc supplementation rescued this phenotype when administered before this meiotic block. However, after telophase arrest, zinc triggered parthenogenesis, suggesting that exit from this meiotic step is tightly regulated by the availability of a zinc-dependent signal. These results implicate the zinc bolus acquired during meiotic maturation as an important part of the maternal legacy to the embryo.


Subject(s)
Mammals/embryology , Meiosis/physiology , Oocytes/cytology , Oocytes/metabolism , Zinc/metabolism , Animals , Chelating Agents/pharmacology , Embryonic Development/drug effects , Embryonic Development/physiology , Female , Meiosis/drug effects , Mice , Microscopy, Fluorescence , Oocytes/drug effects , Oocytes/growth & development , Parthenogenesis/drug effects , Parthenogenesis/physiology , Pregnancy , Telophase/drug effects , Telophase/physiology , Zinc/antagonists & inhibitors
9.
Womens Health (Lond) ; 6(4): 511-6, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20597615

ABSTRACT

The phrase 'women's health research' embraces women as part of the biomedical research engine while categorizing women as separate. Before personalized medicine can become a reality, we must first ensure that basic physiological differences between the sexes are clearly delineated. In this article we argue that research into sex differences should be encouraged at the most fundamental levels of the biomedical sciences. Moreover, appropriate representation of both sexes as participants in clinical studies is still critically needed. Academic and governmental organizations must continue to articulate strong policy in order to ensure inclusion and analysis of sex as a critical variable. Focused attention on sex as a contributing factor to health, disease and therapeutic activity will increase our fund of knowledge regarding our everyday health, increase the pace of clinical research and ensure a healthier population.


Subject(s)
Biomedical Research , Prejudice , Social Justice , Women's Health , Education, Medical , Evidence-Based Medicine , Female , Genomics , Health Services Accessibility , Humans , Male , Preventive Medicine , Sex Factors
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