Obstetric outcomes of nulliparous women with pelvic pain undergoing fertility treatment.

RESEARCH QUESTION: Is there any association between pelvic pain and primary caesarean delivery for patients undergoing assisted reproductive technology (ART) treatment? DESIGN: Retrospective cohort study of nulliparous patients with singleton pregnancies who underwent ART treatment and achieved a live birth between 2012 and 2020. Cases included patients diagnosed with pelvic pain. A 3:1 ratio propensity-score-matched population of patients without a history of pelvic pain was included as the control group. Comparative statistics were performed using chi-squared test and Student's t-test. A multivariate regression analysis was conducted to evaluate the association between pelvic pain and mode of delivery. RESULTS: One hundred and seventy-four patients with pelvic pain were compared with 575 controls. Patients with pelvic pain reported a significantly longer duration of infertility compared with controls (18.98 ± 20.2 months versus 14.06 ± 14.06 months; P = 0.003). Patients with pelvic pain had a significantly higher rate of anxiety disorders (115 ± 21.9 versus 55 ± 31.6; P = 0.009) and use of anxiolytics at embryo transfer (17 ± 3.2 versus 12 ± 6.9; P = 0.03) compared with controls. In addition, patients with pelvic pain had a higher rate of primary caesarean delivery compared with controls (59.8% versus 49.0%; P = 0.01). After adjusting for multiple variables, a significant association was found between pelvic pain and increased odds of primary caesarean delivery (adjusted OR 1.48, 95% CI 1.02-2.1). CONCLUSION: Patients with pelvic pain have significantly higher odds of primary caesarean delivery compared with patients without a history of pelvic pain. The infertility outpatient setting may be uniquely positioned to identify patients at risk for undergoing primary caesarean delivery, and could facilitate earlier intervention for pelvic floor physical therapy during the preconception and antepartum periods.

Single Euploid Embryo Transfer Outcomes After Uterine Septum Resection.

STUDY OBJECTIVE: To study pregnancy outcomes after single euploid embryo transfer (SEET) in patients who underwent prior uterine septum resection to those with uteri of normal contour, without Müllerian anomalies or uterine abnormalities including polyps or fibroids, and without a history of prior uterine surgeries. DESIGN: Retrospective cohort study. SETTING: Single academic affiliated center. PATIENTS: 60 cycles of patients with prior hysteroscopic uterine septum resection who underwent an autologous SEET between 2012 and 2020 were used as the investigational cohort. A 3:1 ratio propensity score matched control cohort of 180 single euploid embryo transfer cycles from patients without a history of uterine septa were used as the control group. INTERVENTIONS: No interventions administered. MEASUREMENTS AND MAIN RESULTS: Pregnancy, clinical pregnancy loss, ongoing clinical pregnancy, and live birth rates in patients with a history of uterine septum resection compared with matched patients without Müllerian anomalies or uterine surgeries. Patients with a prior uterine septum had significantly lower rates of chemical pregnancy (58.33% vs 77.2%, p = .004), implantation (41.67% vs 65.6%, p = .001), and live birth (33.33% vs 57.8%, p = .001) per transfer. No statistical difference in clinical pregnancy loss rates was found when comparing septum patients with controls (8.33% vs 7.8%, p = .89). CONCLUSION: Patients with a history of hysteroscopic resection who undergo in vitro fertilization are more susceptible to suboptimal clinical outcomes compared with patients with normal uteri. Early pregnancy loss rates in patients with a uterine septum are higher than in those without; however, after resection, the rates are comparable. Patients born with septate uteri require assessment of surgical intervention prior to SEET, and to optimize their reproductive outcomes.

Correlation of self-reported racial background to euploidy status and live birth rates in assisted reproductive technology cycles.

PURPOSE: To determine whether the embryonic euploidy rate and live birth outcomes following single, euploid embryo transfer (SEET) differ among women of self-reported racial and ethnic backgrounds. METHODS: This retrospective cohort study included all infertile patients of different self-reported racial backgrounds who underwent In vitro fertilization (IVF) with preimplantation genetic testing for aneuploidy (PGT-A) and an autologous single euploid embryo transfer (SEET) from December 2015 to December 2019 at a single private and academic assisted reproduction technology center. Primary outcome measures included ploidy rates among different racial groups. Secondary outcomes included clinical pregnancy, clinical pregnancy loss, and live birth rates. RESULTS: Five thousand five hundred sixty-two patients who underwent an IVF cycle with ICSI-PGT-A were included. A total of 24,491 blastocysts were analyzed. White participants had on average more euploid embryos and higher euploidy rates when compared to their counterparts (p ≤ 0.0001). However, after controlling for confounding factors, there was no association between race and the odds of having  a higher euploidy rate (aOR 1.31; 95% CI 0.63-2.17, p = 0.42). A total of 4949 patients underwent SEET. Pregnancy outcomes did not differ among patients of varying self-reported races. CONCLUSIONS: Euploidy rates and pregnancy outcomes were comparable among patients of different racial backgrounds who underwent a SEET.

Recent clomiphene citrate exposure does not impact subsequent clinical outcomes in single euploid frozen embryo transfer cycles.

STUDY QUESTION: Do infertile couples who recently utilized clomiphene citrate (CC) for ovulation induction or ovarian stimulation (<90 days previously) followed by a single euploid embryo transfer (SEET) have lower implantation potential compared with patients who were not exposed to CC within 90 days before embryo transfer (ET)? SUMMARY ANSWER: There does not appear to be an association between recent CC exposure and lower implantation potential in patients who undergo a frozen embryo transfer (FET) of euploid embryos. WHAT IS KNOWN ALREADY: Clomiphene has been found to be associated with lower pregnancy rates when compared against other ovarian stimulation medications. The majority of published research about the effects of CC on implantation potential suggest an anti-estrogenic effect on the endometrium. Quality evidence and information about utilization of CC and its effect on implantation potential after euploid ETs is lacking in the literature. STUDY DESIGN, SIZE, DURATION: A retrospective cohort study with propensity score matching was carried out. We included all patients that underwent an autologous SEET from September 2016 to September 2022 at a single academic-private ART center. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study group included patients that had utilized CC during either ovulation induction cycles and/or controlled ovarian stimulation at least 90 days before FET. A propensity score-matched control group of patients that were unexposed to CC within 90 days prior to SEET was used for comparisons. The primary outcome was positive pregnancy test (defined as a positive serum ß-hCG measured 9 days after ET), with other outcomes including clinical pregnancy, ongoing pregnancy, biochemical pregnancy loss, and clinical pregnancy loss rates per SEET. Multivariate regression analyses fitted with generalized estimating equations were utilized to analyze if there was an association between CC utilization and IVF outcomes. Furthermore, the study evaluated the cumulative effect of CC and endometrial receptivity in vivo and subsequent IVF outcomes. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 593 patients with utilization of CC in <90 days before ET were compared with 1779 matched controls. Positive pregnancy test rates were comparable among the control group and the CC exposed groups, respectively (74.3% versus 75.7%, P = 0.79), as were clinical pregnancy (64.0% versus 65.0%, P = 0.60), ongoing pregnancy (51.8% versus 53.2%, P = 0.74), biochemical pregnancy loss (15.7% versus 14.03%, P = 0.45), and clinical pregnancy loss rates were also comparable among cohorts (17.1% versus 18.1%, P = 0.71). No association was found between utilization of clomiphene and lower implantation rates (adjusted odds ratio 0.95, 95% CI 0.76-1.18). Also, no differences were observed in sub-analyses based on multiple CC utilization periods. Finally, no association was found between the number of consecutive cumulative clomiphene cycles and sub-optimal IVF outcomes. LIMITATIONS, REASONS FOR CAUTION: The study has inherent bias that originated from its retrospective design. Serum levels of CC were not measured and sample size for the sub-analyses was small. WIDER IMPLICATIONS OF THE FINDINGS: There does not appear to be an association between recent CC exposure and lower implantation potential in patients who undergo a FET of euploid embryos. This finding remains consistent, even in patients who undergo multiple, consecutive clomiphene cycles prior to ET. There were no long-term effects of CC on endometrial development and clinical characteristics examined in this study. Patients that utilized CC medication prior to a SEET cycle for either ovarian stimulation or ovulation induction, can be assured that there is no evidence of a residual effect of recent CC administration that could jeopardize their pregnancy probability. STUDY FUNDING/COMPETING INTEREST(S): No funding was received for the realization of this study. A.C. is advisor and/or board member of Sema4 (stakeholder in data) and Progyny. The other authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Synthesis, Post-Functionalization and Properties of Diphosphapentaarenes.

Linearly-fused polyarenes are an important class of compounds with high relevance in materials science. While modifying the shape and size represents a common means to fine-tune their properties, the precise placement of heteroatoms is a strategy that is receiving an increasing deal of attention to overcome the intrinsic limitations of all-carbon structures. Thus, linearly-fused diphosphaarenes recently emerged as a novel family of molecules with striking optoelectronic properties and outstanding stability. However, the properties of diphosphaarenes are far from being benchmarked. Herein, we report the synthesis, phosphorus post-functionalization and properties of new diphosphapentaarene derivatives. We describe their synthetic limitations and unveil their potential for optoelectronic applications.

From Terminal to Spiro-Phosphonium Acceptors, Remarkable Moieties to Develop Polyaromatic NIR Dyes.

Phosphonium-based compounds gain attention as promising photofunctional materials. As a contribution to the emerging field, we present a series of donor-acceptor ionic dyes, which were constructed by tailoring phosphonium (A) and extended π-NR2 (D) fragments to an anthracene framework. The alteration of the π-spacer of electron-donating substituents in species with terminal -+ PPh2 Me groups exhibits a long absorption wavelength up to λabs =527 nm in dichloromethane and shifted the emission to the near-infrared (NIR) region (λ=805 nm for thienyl aniline donor), although at low quantum yield (Φ<0.01). In turn, the introduction of a P-heterocyclic acceptor substantially narrowed the optical bandgap and improved the efficiency of fluorescence. In particular, the phospha-spiro moiety allowed to attain NIR emission (797 nm in dichloromethane) with fluorescence efficiency as high as Φ=0.12. The electron-accepting property of the phospha-spiro constituent outperformed that of the monocyclic and terminal phosphonium counterparts, illustrating a promising direction in the design of novel charge-transfer chromophores.

Boundaries of the Hyperconjugation from π-Extended Six-Membered Phosphorus Heterocycles.

In the context of materials science, six-membered phosphorus heterocycles are intriguing building blocks due to their tunable properties through phosphorus post-functionalization and their unique hyperconjugative effects arising from the phosphorus substituents that contribute to further tuning the optoelectronic properties of the system. Seeking for the discovery of improved materials, the latter features have triggered an astonishing evolution of molecular architectures based on phosphorus heterocycles. Theoretical calculations showed that the hyperconjugation causes a reduction in the S0-S1 gap, which strongly depends on the nature of both the P-substituent and the π-conjugated core, but where are the limits? Outlining the hyperconjugative effects of six-membered phosphorus heterocycles would allow scientists to know how to design next-generation organophosphorus systems with enhanced properties. Herein, we discovered that, in cationic six-membered phosphorus heterocycles, an increase in the hyperconjugation does not affect the S0-S1 gap anymore; i.e., quaternizing the phosphorus atoms leads to properties that go beyond those provoked by hyperconjugative effects. DFT calculations revealed that the latter is particularly marked in phosphaspiro derivatives. Our detailed investigations spotlight the potential of π-extended systems based on six-membered phosphorus spiroheterocycles for accessing properties beyond those achieved to date through hyperconjugative effects, thus laying the groundwork for new research possibilities toward improved organophosphorus systems.

Efficacy and safety of a new medicated nail hydrolacquer in the treatment of adults with toenail onychomycosis: A randomised clinical trial.

BACKGROUND: A new water-soluble formulation with ciclopirox has shown a higher penetration than other ciclopirox nail lacquers currently marketed, thus providing a higher concentration of ciclopirox into the nail. OBJECTIVE: To evaluate the efficacy and safety of a new ciclopirox nail hydrolacquer compared with its vehicle and an active comparator (hydroxypropyl chitosan-based 80 mg/g ciclopirox nail lacquer) for the treatment of toenail fungal infection. METHODS: Phase III, multicenter, randomised, double-blind, clinical trial in patients with distal mild to moderate toenail onychomycosis due to dermatophyte fungi. Patients were randomised to apply topically a ciclopirox nail hydrolacquer, its vehicle or a reference product once daily for 48 weeks with a follow-up period of 4 weeks up to week 52. RESULTS: A total of 381 patients were included. No statistically significant differences were observed between patient groups in the proportion of subjects achieving a complete cure. At week 52, a higher percentage of patients in the ciclopirox nail hydrolacquer group achieved a mycological cure (negative for culture and DTS/KOH test, with results: 32.0% ciclopirox nail hydrolacquer, 23.2% vehicle and 27% reference product, respectively), and similar results were found for improvement (mycological cure and reduction of diseased nail ≥20%, with results: 27.2% ciclopirox nail hydrolacquer, 21.6% vehicle and 20.6% reference product, respectively). Regarding mycological results, only ciclopirox nail hydrolacquer demonstrated significant statistical superiority versus vehicle negativizing dermatophyte culture (p = .039) with no recurrences, relapses or re-infections in a four-week follow-up patients with complete cure. The safety profile was comparable to the vehicle and reference product and consistent with the previously reported. CONCLUSIONS: A new water-soluble formulation for a ciclopirox nail lacquer showed similar efficacy to the reference product to eradicate toenail onychomycosis and superiority in the mycological cure defined by negative culture, thus preventing reinfections and recurrences. Efficacy and safety data demonstrate the positive benefit-risk profile of this new topical antifungal preparation. [Correction added on 13 April 2023, after first online publication: The results and conclusions in the Abstract contained incorrect information and were revised in this version.].

Detection of SARS-CoV-2 in a cat owned by a COVID-19-affected patient in Spain.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, is considered a zoonotic pathogen mainly transmitted human to human. Few reports indicate that pets may be exposed to the virus. The present report describes a cat suffering from severe respiratory distress and thrombocytopenia living with a family with several members affected by COVID-19. Clinical signs of the cat prompted humanitarian euthanasia and a detailed postmortem investigation to assess whether a COVID-19-like disease was causing the condition. Necropsy results showed the animal suffered from feline hypertrophic cardiomyopathy and severe pulmonary edema and thrombosis. SARS-CoV-2 RNA was only detected in nasal swab, nasal turbinates, and mesenteric lymph node, but no evidence of histopathological lesions compatible with a viral infection were detected. The cat seroconverted against SARS-CoV-2, further evidencing a productive infection in this animal. We conclude that the animal had a subclinical SARS-CoV-2 infection concomitant to an unrelated cardiomyopathy that led to euthanasia.

Assessing the clinical viability of micro 3 pronuclei zygotes.

PURPOSE: What is the rate of euploidy and clinical viability of embryos resulting from micro 3 pronuclei zygotes? METHODS: Retrospective cohort analysis in a single, academic in vitro fertilization (IVF) center from March 2018 to June 2021. Cohorts were separated by fertilization as either a 2 pronuclear zygote (2PN) or micro 3 pronuclear zygote (micro 3PN). PGT-A was performed to identify embryonic ploidy rates in embryos created from micro 3PN zygotes. The clinical outcomes of all transferred euploid micro 3PN zygotes were evaluated from frozen embryo transfer (FET) cycles. RESULTS: During the designated study period, 75,903 mature oocytes were retrieved and underwent ICSI. Of these, 60,161 were fertilized as 2PN zygotes (79.3%) and 183 fertilized as micro 3PN zygotes (0.24%). Of the micro 3PN-derived embryos that underwent biopsy, 27.5% (n=11/42) were deemed euploid by PGT-A, compared to 51.4% (n=12,301/23,923) of 2PN-derived embryos, p=0.06. Four micro 3PN-derived embryos were transferred in subsequent single euploid FET cycles, which includes one live birth and one ongoing pregnancy. CONCLUSION: Micro 3PN zygotes that develop to the blastocyst stage and meet the criteria for embryo biopsy have the potential to be euploid by preimplantation genetic testing for aneuploidy (PGT-A) and if selected for transfer can achieve a live birth. Although there are a significantly lower number of micro 3PN embryos that make it to blastocyst biopsy, the potential to continue to culture abnormally fertilized oocytes may give these patients a chance at pregnancy that they previously did not have.

2-Phenethylamines in Medicinal Chemistry: A Review.

A concise review covering updated presence and role of 2-phenethylamines in medicinal chemistry is presented. Open-chain, flexible alicyclic amine derivatives of this motif are enumerated in key therapeutic targets, listing medicinal chemistry hits and appealing screening compounds. Latest reports in discovering new bioactive 2-phenethylamines by research groups are covered too.

Availability and characteristics of pulmonary rehabilitation programs in family health centers and hospitals from Chile: Descriptive, retrospective and multicentric study.

OBJECTIVE: To determine availability and characteristics of pulmonary rehabilitation programs performed in 2019 in family health centers and hospitals from Chile. METHODOLOGY: A descriptive and retrospective study was designed, considering PR programs operated in 2019. A non-probability and convenience sample was obtained. Availability and characteristics of centers and PR were measured using a questionnaire translated, modified, validated, and sent by email. RESULTS: Out of 80 responses (22.8%), 60% of centers offered PR program, where the lack of time was the greatest barrier. The programs were mainly outpatient, non-personalized, with 10(IQR 4-11) participants, 12 (IQR 12-16) weeks of length, with 2.4 ± 0.6 session/week, and 1 (IQR 1-2) hours/session. Chronic Obstructive Pulmonary Disease (COPD) was the most frequent diagnostic. The programs were mainly comprised of strength training exercises of lower extremity, upper extremity, walking and education. Team was constituted of physiotherapist and physician, with completed training, and directed by a physiotherapist. Modified Borg, MRC dyspnea scale, six-minute walking test and oximetry were used in the assessments. Between 40-80% of patients completed PR, and the major barrier was patient relocated. CONCLUSION: Increasing PR availability, homogenization of exercises and education, prioritization of assessments supported by scientific evidence, and inclusion of follow-up could be useful to improve the access, quality and results of the treatment, considering new models of PR that allow greater access and acceptability.

Luminescent Pyrrole-Based Phosphaphenalene Gold Complexes: Versatile Anticancer Tools with Wide Applicability.

Invited for the cover of this issue are the groups of Christel Herold-Mende and Carlos Romero-Nieto at the Universities of Heidelberg and Castilla-La Mancha. The image depicts the use of phosphaphenalene gold(I) complexes for the treatment of brain cancer. Read the full text of the article at 10.1002/chem.202104535.

Luminescent Pyrrole-Based Phosphaphenalene Gold Complexes: Versatile Anticancer Tools with Wide Applicability.

Brain cancer, one of the most lethal diseases, urgently requires the discovery of novel theranostic agents. In this context, molecules based on six-membered phosphorus heterocycles - phosphaphenalenes - are especially attractive; they possess unique characteristics that allow precise chemical engineering. Herein, we demonstrate that subtle structural modifications of the phosphaphenalene-based gold(I) complexes lead to modify their electronic distribution, endow them with marked photophysical properties and enhance their efficacy against cancer. In particular, phosphaphenalene-based gold(I) complexes containing a pyrrole ring show antiproliferative properties in 14 cell lines including glioblastomas, brain metastases, meningiomas, IDH-mutant gliomas and head and neck cancers, reaching IC50 values as low as 0.73 µM. The bioactivity of this new family of drugs in combination with their photophysical properties thus offer new research possibilities for both the fundamental investigation and treatment of brain cancer.

Angiotensin II AT2 receptor ligands with phenylthiazole scaffolds.

The syntheses and the AT1R and AT2R binding data of a series of new small molecule ligands are reported. These ligands comprise a phenylthiazole scaffold rather than the biphenyl or phenylthiophene scaffolds found in essentially all of the previously described ligands originating from the nonselective AT1R/AT2R ligand L-162,313 and the AT2R selective agonist C21, the latter now in Phase II/III clinical trials. A phenylthiazole rather than the phenylthiophene scaffold that is present in the AT2R selective agonist C21 and in the AT2R selective antagonist C38 had a deleterious effect on the affinity to AT2R. Nevertheless, a significant improvement could be accomplished by introduction of a small bulky alkyl group in the 2-position of the imidazole ring attached through a methylene group bridge to the phenylthiazole scaffold. Hence, a combination of a 2-tert-butyl or a 2-isopropyl group and a butoxycarbonyl furnished potent AT2R selective ligands. Furthermore, a high affinity ligand derived from L-162,313 and exhibiting a > 35 fold selectivity for AT1R was identified (10). The ligand 21 with the 2-tert-butyl group and âˆ¼ 35 fold selectivity for AT2R, demonstrated high stability in human, rat and mouse liver microsomes and a very attractive profile with regard to the inhibition of common drug-metabolizing CYP enzymes. Thus, very low levels of inhibition of CYP 3A (5%), 2D6 (12%), 2C8 (26%), 2C9 (23%) and 2B6 (24%) were observed with the 2-tert-butyl derivative comprising the methoxycarbonyl sulfonamide function, levels that are significantly lower than those obtained with C21 under the same experimental conditions.

Reduced humoral response 3 months following BNT162b2 vaccination in SARS-CoV-2 uninfected residents of long-term care facilities.

BACKGROUND: SARS-CoV-2 vaccination is the most effective strategy to protect older residents of long-term care facilities (LTCF) against severe COVID-19, but primary vaccine responses are less effective in older adults. Here, we characterised the humoral responses of institutionalised seniors 3 months after they had received the mRNA/BNT162b2 vaccine. METHODS: plasma levels of SARS-CoV-2-specific total IgG, IgM and IgA antibodies were measured before and 3 months after vaccination in older residents of LTCF. Neutralisation capacity was assessed in a pseudovirus neutralisation assay against the original WH1 and later B.1.617.2/Delta variants. A group of younger adults was used as a reference group. RESULTS: three months after vaccination, uninfected older adults presented reduced SARS-CoV-2-specific IgG levels and a significantly lower neutralisation capacity against the WH1 and Delta variants compared with vaccinated uninfected younger individuals. In contrast, COVID-19-recovered older adults showed significantly higher SARS-CoV-2-specific IgG levels after vaccination than their younger counterparts, whereas showing similar neutralisation activity against the WH1 virus and an increased neutralisation capacity against the Delta variant. Although, similarly to younger individuals, previously infected older adults elicit potent cross-reactive immune responses, higher quantities of SARS-CoV-2-specific IgG antibodies are required to reach the same neutralisation levels. CONCLUSIONS: although hybrid immunity seems to be active in previously infected older adults 3 months after mRNA/BNT162b2 vaccination, humoral immune responses are diminished in COVID-19 uninfected but vaccinated older residents of LTCF. These results suggest that a vaccine booster dose should be prioritised for this particularly vulnerable population.

Biological relevance of trophectoderm morphology: initial ß-hCG measurements correlate with trophectoderm grading on euploid frozen embryo transfers.

OBJECTIVE: To analyze the correlation between TE grading and initial ß-hCG serum level after single euploid embryo transfer. Secondarily, to explore the association between TE grading with subsequent IVF outcomes. DESIGN: Retrospective cohort analysis. SETTING: Single, academic, private infertility and assisted reproductive care institute. PATIENTS OR OTHER PARTICIPANTS: Infertility patients who underwent a single euploid embryo transfer that resulted in a positive pregnancy test. INTERVENTION(S): ß-hCG measurements. MAIN OUTCOME MEASURE(S): Correlation between TE grade with first ß-hCG measurement. Second outcome measurements included ongoing pregnancy, biochemical pregnancy loss, and clinical pregnancy loss rates. RESULTS: 2,798 cases were analyzed. A significant difference in initial ß-hCG measurement among groups (TE A: median 143.4 mIU/mL IQR 79.2-211.2; TE B: 119 mIU/mL IQR 57.1-177.8; TE C: 82.4 mIU/mL IQR 36.3-136.4, p ≤ 0.0001) was observed. There was a significant correlation found between the TE grade and ß-hCG measurements (p ≤ 0.0001, r2 = 0.10). TE grade was not associated with higher odds of biochemical pregnancy loss (TE A vs. TE B: aOR 1.01 CI95% 0.97-1.05; TE A vs. TE C: aOR 1.03 CI95% 0.98-1.08), or higher odds of clinical pregnancy loss (TE A vs. TE B: aOR 1.02 CI95% 0.98-1.05; TE A vs. TE C: aOR 1.03 CI95% 0.98-1.07). CONCLUSIONS: In patients with euploid embryos, TE grade correlates with the first pregnancy test measurement of ß-hCG. We propose this finding helps to appoint a relevant link between morphology assessment and early embryo development in vivo.

Humoral immune responses and neutralizing antibodies against SARS-CoV-2; implications in pathogenesis and protective immunity.

The magnitude and the quality of humoral responses against SARS-CoV-2 have been associated with clinical outcome. Although the elicitation of humoral responses against different viral proteins is rapid and occurs in most infected individuals, its magnitude is highly variable among them and positively correlates with COVID-19 disease severity. This rapid response is characterized by the almost concomitant appearance of virus-specific IgG, IgA and IgM antibodies that contain neutralizing antibodies directed against different epitopes of the Spike glycoprotein. Of particularly interest, the antibodies against domain of the Spike that interacts with the cellular receptor ACE2, known as the receptor binding domain (RBD), are present in most infected individuals and are block viral entry and infectivity. Such neutralizing antibodies protect different animal species when administered before virus exposure; therefore, its elicitation is the main target of current vaccine approaches and their clinical use as recombinant monoclonal antibodies (mAbs) is being explored. Yet, little information exists on the duration of humoral responses during natural infection. This is a key issue that will impact the management of the pandemic and determine the utility of seroconversion studies and the level of herd immunity. Certainly, several cases of reinfection have been reported, suggesting that immunity could be transient, as reported for other coronaviruses. In summary, although the kinetics of the generation of antibodies against SASR-CoV-2 and their protective activity have been clearly defined, their role in COVID-19 pathogenesis and the length of these responses are still open questions.

The association between prior cesarean delivery and subsequent in vitro fertilization outcomes in women undergoing autologous, frozen-thawed single euploid embryo transfer.

BACKGROUND: The rates of cesarean deliveries continue to increase worldwide. Previous work suggests an association between a previous cesarean delivery and reduced fertility in natural conception and in vitro fertilization treatment cycles. To our knowledge, there is no published research that explored the relationship between a previous cesarean delivery and the clinical outcomes after in vitro fertilization and the subsequent transfer of a single frozen-thawed euploid embryo. OBJECTIVE: This study aimed to investigate the relationship between the previous mode of delivery and subsequent pregnancy outcomes in patients undergoing a single frozen-thawed euploid embryo transfer after in vitro fertilization. STUDY DESIGN: A retrospective cohort study was performed at a single academic fertility center from January 2012 to April 2020. All women with a history of a live birth undergoing autologous, frozen-thawed single euploid embryo transfers were identified. Cases included patients with a single previous cesarean delivery; controls included patients with a single previous vaginal delivery. Only the first embryo transfer cycle was included. The primary outcome was the implantation rate. Secondary outcomes included ongoing pregnancy and live birth rates, biochemical pregnancy rate, and clinical miscarriage rate. RESULTS: A total of 525 patients met the inclusion criteria and were included in the analysis. Patients with a previous cesarean delivery had a higher body mass index (24.5±4.5 vs 23.4±4.1; P=.004) than those in the vaginal delivery cohort; the rest of the demographic data were otherwise similar. In a univariate analysis, the implantation rate was significantly lower in patients with a previous cesarean delivery (111/200 [55.5%] vs 221/325 [68.0%]; P=.004). After adjusting for the relevant covariates, a previous cesarean delivery was associated with a 48% reduction in the odds of implantation (adjusted odds ratio, 0.52; 95% confidence interval, 0.34-0.78; P=.002). In addition, after adjusting for the same covariates, a previous cesarean delivery was significantly associated with a 39% reduction in the odds of an ongoing pregnancy and live birth (adjusted odds ratio, 0.61; 95% confidence interval, 0.41-0.90; P=.01). There were no differences in the biochemical pregnancy rates or clinical miscarriage rates. CONCLUSION: This study demonstrated a marked reduction in implantation and ongoing pregnancy and live birth associated with a previous cesarean delivery in patients undergoing a single euploid embryo transfer. Our work stresses the importance of reducing the primary cesarean delivery rates at a national level and elucidating the mechanisms behind the substantially lower implantation rates after a cesarean delivery.

High sensitivity of invertebrate detritivores from tropical streams to different pesticides.

Freshwater organisms are often sensitive to pesticides, but their sensitivity varies across different taxa and with pesticide type and action mode, as shown by multiple acute toxicity tests. Such variability hampers predictions about how freshwater ecosystems may be altered by pesticide toxicity, which is especially critical for understudied areas of the world such as the tropics. Furthermore, there is little information about the sensitivity of some organisms that are key components of stream food webs; this is the case of litter-feeding detritivorous invertebrates, which contribute to the fundamental process of litter decomposition. Here, we examined the sensitivity of three common detritivores [Anchytarsus sp. (Coleoptera: Ptilodactylidae), Hyalella sp. (Amphipoda: Hyalellidae) and Lepidostoma sp. (Trichoptera: Lepidostomatidae)] to three pesticides commonly used (the insecticides bifenthrin and chlorpyrifos and the fungicide chlorothalonil) using acute (48 or 96 h) toxicity tests. Our study demonstrates that common-use pesticides provoke the mortality of half their populations at concentrations of 0.04-2.7 µg L-1. We found that all species were sensitive to the three pesticides, with the highest sensitivity found for chlorpyrifos. Additionally, we used the approach of species sensitivity distributions (SSD) to compare our study species with Daphnia magna and other temperate and tropical invertebrates. We found that the study species were among the most sensitive species to chlorpyrifos and chlorothalonil. Our results suggest that tropical detritivores merit special attention in ecological risk assessment of pesticides and highlight the need for accurate ecotoxicological information from ecologically relevant species in the tropics.