1,720,990 research outputs found
No evidence for SARS-CoV-2 presence in ovarian tissue and peritoneal cavity from a COVID-19 positive woman undergoing urgent fertility preservation procedure
No full textLaparoscopic medulla-sparing ovarian tissue biopsy for cryopreservation: step-by-step surgical technique
No full textObjective: To describe a laparoscopic technique for ovarian tissue biopsy (OTB) for fertility preservation. In the last years, the demand for fertility preservation has grown because of the increasing survival rates among patients with cancer and the rising awareness of the importance of quality of life after gonadotoxic therapy. Among fertility-sparing approaches, ovarian tissue cryopreservation is a valid strategy to preserve ovarian endocrine and reproductive function in prepubertal and postpubertal women who will undergo gonadotoxic cancer treatments. Currently, there is no universal consensus regarding ovarian tissue retrieval technique for fertility preservation. Design: Step-by-step description of the surgical technique with narrated video footage. Setting: Academic tertiary hospital. Patient(s): Patients with a high risk of premature ovarian insufficiency, usually due to gonadotoxic treatments, who undergo OTB for fertility preservation were included in the study. In this video, we present the clinical case of a 28-year-old patient affected by Hodgkin lymphoma who underwent laparoscopy for OTB before chemotherapy. Intervention(s): After exposing the chosen ovary, an incision at the tubal pole of the ovary is made with scissors. Through section and dissection, a large cortical biopsy of the ovary is performed without removing and avoiding any damage to the medulla. At the end of the procedure, hemostasis was achieved with selective coagulation using bipolar coagulation. Main outcome measure(s): Step by step educational video. Result(s): The post-operative course was uneventful and the patient was discharge 24 hours after surgery. Conclusion(s): Standardization of a step-by-step laparoscopic technique can provide an effective method to optimize ovarian tissue removal while minimizing tissue injury. Medulla-sparing ovarian biopsy allows retrieval of only the cortical part of the ovary, maximizing the number of primordial follicles obtained without damaging the vascular supply of the ovary contained within the medulla. Primordial follicles are resistant to cryoinjury owing to their relatively inactive metabolism, and they are usually found at approximately 0.8 mm below the surface of the cortex. This technique could also reduce the back-table processing time of the ovarian tissue before cryopreservation. One disadvantage could be the difficulty of the technique compared to an oophorectomy because it requires a skilled surgeon that can easily find the cleavage plane between the medulla and the cortex, even in patients submitted to previous chemoradiotherapy or during gonadotropin-releasing hormone analogue therapy
Ovarian tissue biopsy for cryopreservation by vaginal natural orifice transluminal endoscopic surgery: a new approach for a minimal invasive ovarian biopsy
No full textObjective: Vaginal natural orifice transluminal endoscopic surgery (vNOTES) is an emerging surgical procedure that combines the advantages of the vaginal approach with laparoscopic vision and instrumentation. Shorter hospitalization and lesser postoperative pain associated with vNOTES may be explained by the advantages of this innovative surgical approach (e.g., absence of abdominal incisions, shorter operative time, and lower insufflation pressure). Ovarian tissue cryopreservation allows to preserve reproductive and endocrine functions in young women with oncological disease at risk of premature ovarian insufficiency (POI) caused by gonadotoxic treatments. Ovarian tissue biopsy for cryopreservation consists of a large biopsy of 1 or both ovaries that is usually performed by laparoscopy. Then, the removed ovarian tissue is cryopreserved for the future transplant after cancer remission. The volume of ovarian biopsy ranges from 50% of the ovary for women at moderate risk of POI to 70%–100% of it for those at high risk. The inclusion criteria for ovarian tissue cryopreservation are women aged <35 years who cannot delay start of oncological treatments for follicle cryopreservation, with a moderate or high risk of POI and good chance of 5-year survival. Ovarian tissue cryopreservation cannot be performed if tumor treatments include uterine irradiation or for tumors at risk of ovarian metastases (as in the case of ovarian cancer, leukemia, neuroblastoma, or Burkitt lymphoma). Despite widespread adoption of vNOTES in gynecology, ovarian biopsy for cryopreservation has never been performed using this route. Design: Step-by-step explanation of the procedure with descriptive text and narrated video footage. Setting: Tertiary-level referral academic center. Patient(s): A 27-year-old patient recently diagnosed with low-grade follicular non-Hodgkin lymphoma was referred to our center for ovarian tissue cryopreservation before chemotherapy. The patient included in this study gave informed consent for publication of the video and posting of the video online including social media, the journal website, scientific literature websites (e.g., PubMed, ScienceDirect, and Scopus), and other applicable sites. Because of the nature of the study, institutional review board approval was not required. Intervention(s): Access to the peritoneal cavity was created by a 3-cm posterior colpotomy. The peritoneum was then opened using cold scissors and temporarily fixed to the posterior vaginal wall. The GelPOINT Mini Advanced Access Platform (Applied Medical, Rancho Santa Margarita, CA), with 1 10-mm and 2 5-mm trocars, was used as the vNOTES port. The inner Alexis ring of the GelPOINT was inserted through the colpotomy into the pouch of Douglas. A hysterometer was placed into the uterine cavity to keep the uterus anteverted during the surgery. A pneumoperitoneum was created to a pressure of 8 mm Hg, and the operating table was tilted to a 20° Trendelenburg position. A 10-mm rigid 30° camera was inserted in the inferior and larger trocar, and both ovaries were visualized. Seventy percent of the left ovary was removed with cold scissors to minimize trauma on the surgical specimen. After removal of the GelPOINT cap, ovarian biopsy was immediately picked up by the biologist of our fertility center. The ovary was coagulated with a bipolar instrument. The hysterometer was then replaced by a uterine manipulator to perform tubal patency test, and blue dye passage through both salpinges was observed. Finally, the Alexis retractor and stich on the posterior peritoneum were removed, and the vagina was sutured using interrupted stiches. The total operative time was 25 minutes. Main Outcomes Measure(s): Ovarian tissue biopsy for cryopreservation by vNOTES. Result(s): No intraoperative and postoperative complications were reported, and the patient was discharged after 24 hours from surgery. Conclusion(s): Vaginal natural orifice transluminal endoscopic surgery may be a feasible alternative approach to laparoscopy for ovarian tissue cryopreservation: it allows an easy access to the ovaries and removal of different tissue volumes. Patients undergoing ovarian cryopreservation may benefit from the vNOTES approach because a rapid postoperative recovery is crucial to start chemotherapy in a short time. As for other vNOTES procedures, accurate selection of patients seems to be crucial for a successful ovarian tissue cryopreservation. We believe that the inclusion and exclusion criteria reported for other gynecologic procedures performed through vNOTES may also be valid for ovarian tissue cryopreservation by vNOTES. Women at high risk of pelvic adhesions (e.g., coexistent endometriosis, previous pelvic surgery, or inflammatory pelvic disease), those with an increased body mass index or enlarged uterus, and those with cervical, vaginal, or uterine cancer cannot be considered for this approach because all these factors are associated with failure of vNOTES. On the other hand, women with no history of surgery, endometriosis, and large myomas may benefit from the vNOTES approach, and these women represent most of patients who undergo ovarian tissue cryopreservation. Further and larger studies are needed to assess the efficacy and safety of this new approach
High cytokine expression and reduced ovarian reserve in patients with Hodgkin lymphoma or non-Hodgkin lymphoma
No full textOBJECTIVE:
To investigate the ovarian reserve in female lymphoma patients and the potential relationships with the cytokine network.
DESIGN:
Age-matched control study.
SETTING:
Women's university hospital.
PATIENT(S):
Seventy-three lymphoma patients (57 with classic Hodgkin lymphoma [HL] and 16 with non-Hodgkin lymphoma [NHL]), approaching our center for ovarian tissue cryopreservation (study group) were compared with 25 age-matched healthy volunteers (control group).
INTERVENTION(S):
Measurements of antimüllerian hormone (AMH), soluble interleukin-2 receptor (SIL-2R), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor α (TNF-α) levels.
MAIN OUTCOME MEASURE(S):
The AMH and cytokine levels of the lymphoma patients and the healthy volunteers were compared. Correlations between AMH with SIL-2R, IL-6, and IL-8 levels were performed.
RESULT(S):
The AMH showed significant lower concentrations in lymphoma patients than in the control group. Higher significant concentrations in lymphoma patients than in control group were found for SIL-2R and IL-6. No differences were observed comparing HL and NHL groups and within the stages of HL group for AMH and all the cytokines analyzed. Finally, significant inverse correlations were observed in lymphoma patients between AMH and SIL-2R, IL-6, and IL-8 levels, but not with TNF-α levels. Positive correlations between SIL-2R with IL-6, and IL-6 with IL-8 were also shown.
CONCLUSION(S):
In patients with HL or NHL at baseline the cytokine network is particularly active and the ovarian reserve is reduced. A strong negative correlation between AMH and SIL-2R, IL-6, and IL-8 has been also evidenced
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
New insights in the selection and management of cancer patients applicants for ovarian tissue cryopreservation
No full textOvarian tissue cryopreservation (OTC), representing a promising strategy to preserve ovarian function in cancer patients, is recommended to women younger than 35 years. This study aimed to identify endocrine and biometric parameters as additional selection criteria for OTC. One hundred and ninety-one cancer patients before chemoradiotherapy and OTC and 43 controls were investigated. Mean ± SD, median, quartiles, 5th and 95th centiles and correlations of FSH, LH, estradiol, inhibin-B, anti-Mullerian hormone (AMH), ovarian volume and antral follicle count (AFC) were assessed. Most ovarian reserve parameters presented typical variations of ovulatory menstrual cycle, except AMH and AFC showing minimal fluctuations across the menstrual cycle. The 5th centiles of AMH (0.31and 0.4 ng/mL in controls and cancer patients, respectively) and AFC (five follicular structures in both groups) could be conjectured as minimum thresholds to include patients aged <35 years in OTC; below this threshold patients of any age should be excluded from OTC. Conversely, patients with AMH and AFC above the 25th centiles (1.2-1.6 ng/mL and 9-10 follicular structures in controls and cancer patients, respectively) might be inserted in OTC regardless of age. Baseline assessment of AMH and AFC might be considered as selection criteria, in addition to chronological age, to take decision of OTC in cancer patient
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
