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Bacteriophage ΦKZ (PhiKZ) is the founding member of a family of giant bacterial viruses. It has potential as a therapeutic as its host, Pseudomonas aeruginosa, kills tens of thousands of people worldwide each year. ΦKZ infection is independent of the host transcriptional apparatus; the virus forms a "nucleus", producing a proteinaceous barrier around the ΦKZ genome that excludes the host immune systems. It expresses its own non-canonical multi-subunit non-virion RNA polymerase (nvRNAP), which is imported into its "nucleus" to transcribe viral genes. The ΦKZ nvRNAP is formed by four polypeptides representing homologues of the eubacterial β/β' subunits, and a fifth that is likely to have evolved from an ancestral homologue to σ-factor. We have resolved the structure of the ΦKZ nvRNAP initiating transcription from its cognate promoter, p119L, including previously disordered regions. Our results shed light on the similarities and differences between ΦKZ nvRNAP mechanisms of transcription and those of canonical eubacterial RNAPs and the related non-canonical nvRNAP of bacteriophage AR9., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Research Question: Could the total dose (<3000 IU or ≥3000 IU) and type of exogenous gonadotrophin (i.e. recombinant FSH and/or human menopausal gonadotrophin [HMG]) influence aneuploidy and blastulation rates and produce different reproductive outcomes?, Design: This retrospective, observational, multicentre cohort study included a total of 8466 patients undergoing IVF using autologous oocytes and preimplantation genetic testing for aneuploidies. Participants were divided according to the dosage of total gonadotrophins and stratified by maternal age., Results: The aneuploidy rates, pregnancy outcomes and cumulative live birth rates (CLBR) were similar among women who received total gonadotrophin dosages of <3000 or ≥3000 IU. No statistical differences were reported in the blastulation rate with lower or higher gonadotrophin dosages. Women receiving a higher amount of HMG during ovarian stimulation had a lower aneuploidy rate (P = 0.02); when stratified according to age, younger women with a higher HMG dosage had lower aneuploidy rates (P< 0.001), while no statistical differences were observed in older women with higher or lower HMG dosages. No significant differences were observed in IVF outcomes or CLBR., Conclusions: High doses of gonadotrophins were not associated with rate of aneuploidy. However, an increased fraction of HMG in younger women was associated with a lower aneuploidy rate. The study demonstrated that the total gonadotrophin dosage did not influence aneuploidy, reproductive outcomes or CLBR. The increased gonadotrophin and HMG dosages used for ovarian stimulation did not precede aneuploidy, and the use of HMG should be evaluated on a case-by-case basis, according to the individual's characteristics and infertility type., (Copyright © 2024 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Protein glycosylation is a post-translational modification involved in wide range of biological processes. In mammalian spermatozoa this modification has been identified in numerous proteins, and membrane glycoproteins are involved in the fertilization process. The objective of the present study was to identify changes in protein glycosylation after acrosome reaction (AR) induction using the 4-Br-A23187 ionophore. Our results showed that treatment with 10 μM of 4-Br-A23187 for 20 min significantly increased the percentage of live acrosome-reacted spermatozoa compared to the control (69.8 ± 0.8 vs. 6.4 ± 0.5; mean % ± SEM, respectively). Also, we observed an increase in 32 kDa tyrosine-phosphorylated protein (p32) and a decrease in serine/threonine phosphorylation of the protein kinase A substrates (phospho-PKA-substrates) after ionophore treatment. Furthermore, changes in glycosylated proteins following AR induction were analyzed using different HRP-conjugated lectins (GNA, DSA, and SNA), revealing changes in mannose and sialic acid residues. Proteomic analysis of isolated proteins using GNA lectin revealed that 50 proteins exhibited significantly different abundance (q-value < 0.01). Subsequent analysis using Uniprot database identified 39 downregulated and 11 upregulated proteins in the presence of 4-Br-A23187. Notably, six of these proteins were classified as transmembrane proteins, namely LRRC37A/B like protein 1 C-terminal domain-containing protein, Membrane metalloendopeptidase like 1, VWFA domain-containing protein, Syndecan, Membrane spanning 4-domains A14 and Serine protease 54. This study shows a novel protocol to induce acrosome reaction in boar spermatozoa and identifies new transmembrane proteins containing mannose residues. Further work is needed to elucidate the role of these proteins in sperm-oocyte fusion., Competing Interests: Declaration of competing interest The authors have declared that no competing interests exist., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Research Question: How do cancer type and treatment affect semen quality before and after treatment, and what effect does it have in their clinical management of infertility? Also, what is the rate of patients using cryopreserved semen samples after treatment?, Design: Patients who cryopreserved spermatozoa for oncological reasons between 2000 and 2022 in IVI clinics in Spain were retrospectively reviewed. Semen parameters were analysed before and after treatment, and utilization and destruction rates were calculated. Total motile sperm count (TMSC) was used for assisted reproductive technology (ART) counselling., Results: A total of 724 patients cryopreserved their semen during the study period. The semen parameters of the cancer patients' semen before and after treatment were heterogeneous, with significant differences between cancer type and semen parameters. The utilization rate was relatively low (0.4%), whereas the destruction rate was 23.1%., Conclusion: Cancer and antineoplastic treatment affect everyone differently. Therefore, sperm cryopreservation should be offered to all patients before starting treatment to ensure their reproductive future. Furthermore, in addition to considering the semen parameters defined by the World Health Organization, it is important to use TMSC in the diagnosis of men to choose appropriate ART according to type of cancer., (Copyright © 2024 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Thymol-loaded PLGA nanoparticles (TH-NPs) were incorporated into different semi-solid formulations using variable gelling agents (carbomer, polysaccharide and poloxamer). The formulations were physicochemically characterized in terms of size, polydispersity index and zeta potential. Moreover, stability studies were performed by analyzing the backscattering profile showing that the gels were able to increase the nanoparticles stability at 4 °C. Moreover, rheological properties showed that all gels were able to increase the viscosity of TH-NPs with the carbomer gels showing the highest values. Moreover, the observation of carbomer dispersed TH-NPs under electron microscopical techniques showed 3D nanometric cross-linked filaments with the NPs found embedded in the threads. In addition, cytotoxicity studies showed that keratinocyte cells in contact with the formulations obtained cell viability values higher than 70 %. Furthermore, antimicrobial efficacy was assessed against C. acnes and S. epidermidis showing that the formulations eliminated the pathogenic C. acnes but preserved the resident S. epidermidis which contributes towards a healthy skin microbiota. Finally, biomechanical properties of TH-NPs dispersed in carbomer gels in contact with healthy human skin were studied showing that they did not alter skin properties and were able to reduce sebum which is increased in acne vulgaris. As a conclusion, TH-NPs dispersed in semi-solid formulations and, especially in carbomer gels, may constitute a suitable solution for the treatment of acne vulgaris., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Research Question: Does rescue in-vitro maturation (IVM) in the presence or absence of cumulus cells, affect the progress of meiosis I, compared with oocytes that mature in vivo?, Design: This prospective study was conducted in a university-affiliated fertility centre. Ninety-five young oocyte donors (mean age 25.57 ± 4.47) with a normal karyotype and no known fertility problems were included. A total of 390 oocytes (116 mature metaphase II [MII] and 274 immature oocytes) were analysed. The immature oocytes underwent rescue IVM in the presence of cumulus cells (CC; IVM+CC; n = 137) or without them (IVM-CC; n = 137), and IVM rate was calculated. Chromosome copy number analysis using next-generation sequencing (NGS) was performed on all rescue IVM oocytes reaching MII as well as those that were mature at the time of initial denudation (in-vivo-matured oocytes [IVO])., Results: Maturation rates were similar in IVM+CC and IVM-CC oocytes (62.8 versus 71.5%, P = 0.16). Conclusive cytogenetic results were obtained from 65 MII oocytes from the IVM+CC group, 87 from the IVM-CC group, and 99 from the IVO group. Oocyte euploidy rates for the three groups were similar, at 75.4%, 83.9% and 80.8%, respectively (P = 0.42)., Conclusions: The results suggest that culture of germinal vesicle and metaphase I oocytes in the presence of cumulus cells does not improve rates of IVM. In general, the process of rescue IVM does not appear to alter the frequency of oocytes with a normal chromosome copy number., (Copyright © 2023 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Is magnetic-activated cell sorting (MACS) a safe semen sample processing technique for newborns and mothers when used for semen processing prior to intracytoplasmic sperm injection (ICSI) cycles?, Design: This retrospective multicentre cohort study involved patients undergoing ICSI cycles with either donor or autologous oocytes from January 2008 to February 2020. They were divided into two groups: those who underwent standard semen preparation (reference group) and those who had an added MACS procedure (MACS group). A total of 25,356 deliveries were assessed in the case of cycles using donor oocytes, and 19,703 deliveries from cycles using autologous oocytes. Of these, 20,439 and 15,917, respectively, were singleton deliveries. Obstetric and perinatal outcomes were retrospectively assessed. All means, rates and incidences were computed per live newborn in each study group., Results: There were no significant differences between the main obstetric and perinatal morbidities affecting the mothers' and newborns' well-being between groups using either donated or autologous oocytes. There was a significant increase in the incidence of gestational anaemia in both subpopulations (donor oocytes P = 0.01; autologous oocytes P < 0.001). However, this incidence was within the estimated prevalence for gestational anaemia in the general population. There was a statistically significant decrease in preterm (P = 0.02) and very preterm (P = 0.01) birth rates in the MACS group in cycles using donor oocytes., Conclusions: The use of MACS during semen preparation before ICSI using either donor or autologous oocytes appears to be safe for the mothers' and newborns' well-being during pregnancy and birth. Nevertheless, a close follow-up of these parameters in the future is advised, especially concerning anaemia, in order to detect even smaller effect sizes., (Copyright © 2023 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Is seminal oxidation-reduction potential (ORP) clinically relevant to reproductive outcome?, Design: Prospective observational study including a total of 144 couples who had an intracytoplasmic sperm injection (ICSI) cycle between June 2018 and December 2020. The study included patients undergoing fresh ICSI cycles with autologous gametes. Cycles that had day 3 embryo transfers and cryopreservation cycles were excluded. There was no restriction on patients with severe male infertility; couples with unexplained infertility and unexplained male infertility were included, those with azoospermia were excluded. Semen analysis, seminal ORP as determined by means of the MiOXSYS system, sperm DNA fragmentation (SDF) and reproductive outcomes (fertilization, blastocyst development, clinical pregnancy and live birth) were determined., Results: Seminal ORP was significantly negatively correlated with fertilization rate (r = -0.267; P = 0.0012), blastocyst development rate (r = -0.432; P < 0.0001), implantation/clinical pregnancy (r = -0.305; P = 0.0003) and live birth (r = -0.366; P < 0.0001). Receiver operating characteristic curve analysis showed significant predictive power for ORP for fertilization (≥80%; area under the curve [AUC] 0.652; P = 0.0012), blastocyst development rate (≥60%; AUC 0.794; P < 0.0001), implantation/clinical pregnancy (AUC 0.680; P = 0.0002) and live birth (AUC 0.728; P < 0.0001). Comparable results were obtained for SDF (fertilization: AUC 0.678; blastocyst development: AUC 0.777; implantation/clinical pregnancy: AUC 0.665; live birth: AUC 0.723). Normal sperm morphology showed the lowest predictive power for all reproductive outcome parameters. With male age as confounding factor, ORP (cut-off value of 0.51 mV/10 6 sperm/ml) has significant (P < 0.04667) effects on odds ratios for all reproductive outcome parameters. Multivariate logistic regression to investigate potential seminal and female confounding factors revealed that seminal ORP significantly (P < 0.0039; P < 0.0130) affects reproductive outcome., Conclusion: Seminal ORP is relevant for good fertilization, blastocyst development, implantation, clinical pregnancy and live birth., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Research Question: Does the COVID-19 vaccination affect endometrial receptivity after single euploid embryo transfer, measured by sustained implantation rate?, Design: A retrospective cohort study analysing two groups of single euploid embryo transfers using own oocytes: one historical cohort of 3272 transfers 1 year before the pandemic; and one comprising 890 transfers in women previously vaccinated with mRNA vaccines against severe acute respiratory syndrome coronavirus 2. The main outcomes were clinical pregnancy rate (CPR) and sustained implantation rate (SIR) per embryo transfer. These outcomes were compared between non-vaccinated and vaccinated women, and women who had received one and two doses. Lastly, vaccinated women were divided into quartiles according to the time from last dose to embryo transfer., Results: Similar CPR and SIR were found between non-vaccinated and vaccinated women, and the odds ratio for both outcomes was not statistically significant after being controlled for potential confounders (OR 0.937, 95% CI 0.695 to 1.265 and OR 0.910, 95% CI 0.648 to 1.227 respectively). Within the vaccinated group, women who had received one or two doses also had similar outcomes. In addition, no differences were found according to the time interval from vaccination to embryo transfer., Conclusion: The administration of mRNA vaccines against COVID-19 had no effect on endometrial receptivity and embryo implantation, regardless of the number of doses and time interval from vaccination to embryo transfer. The potential negative effect of the vaccine on endometrial receptivity and reproductive outcomes is reassuring for patients in the process of undergoing assisted reproductive treatment., (Copyright © 2022 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Does sperm DNA fragmentation (SDF) affect reproductive success of IVF and intracytoplasmic sperm injection (ICSI) cycles measured as cumulative live birth rates (CLBR) in unselected couples?, Design: Clinical data from 1339 couples undergoing 2759 IVF/ICSI cycles using autologous oocytes with a SDF test by TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling (TUNEL) assay on their ejaculated spermatozoa were retrospectively evaluated. Main outcomes were calculated according to two different analyses: using 15% SDF as cut-off point (low ≤15% and high >15%); and categorizing participants based on four SDF ranges (<10%, 10- <20%, 20-30% and >30%). Live birth rate and CLBR per number of embryo transfers, per number of embryos replaced and consumed oocytes required to achieve the first live birth according to level of SDF were the main outcomes assessed., Results: No significant difference was found in clinical pregnancy rate and miscarriage rate between both groups. No differences in LBR per embryo transfer were found for the first or for all embryo transfers when comparing ≤15% and >15% sperm DNA fragmentation or by SDF ranges. The CLBR according to the number of embryo transfers and the number of embryos replaced showed no statistically significant differences between different SDF groups. When the same number of oocytes were inseminated, similar CLBR were obtained regardless of the degree of male sperm DNA fragmentation., Conclusions: High SDF did not impair live birth rates of unselected males undergoing IVF/ICSI cycles with autologous oocytes per transfer or the cumulative probability of a live birth., (Copyright © 2022 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Does magnetic-activated cell sorting (MACS) for sperm selection increase cumulative live birth rates (CLBR) or improve clinical parameters of reproductive success in couples undergoing intracytoplasmic sperm injection (ICSI) with donor oocytes?, Design: Retrospective multicentre observational study including data compiled from unselected couples who underwent ICSI cycles with donated oocytes in 15 Spanish IVIRMA fertility clinics (January 2008 to February 2020). Patients were divided into reference (standard semen processing, n = 40,157) and MACS (additional sperm selection step by MACS, n = 1,240) groups. CLBR were plotted on Kaplan-Meier curves and compared using the Mantel-Cox test. Proportions were compared with a generalized estimating equation model, and results were adjusted to clinically relevant variables., Results: The MACS group showed a 27.1% CLBR after one embryo was transferred and 81.6% after four; the reference group had CLBR of 19.6% and 78.5%, respectively. CLBR in the MACS group was 4.2% after five oocytes were used and 75.5% after 15; for the reference group, CLBR were 7.8% and 78.3%, respectively. Kaplan-Meier curves showed statistically significant differences in CLBR per number of embryos transferred and per number of donated metaphase II oocytes between the two groups (both P < 0.0001), but not for CLBR per embryo transfer. No significant differences between groups were found for classical clinical outcomes such as pregnancy and live birth rates per embryo transfer., Conclusions: Although MACS sperm selection slightly increased the CLBR per embryo transferred compared with the reference group, this change was not clinically meaningful. MACS should not be recommended indiscriminately to all infertile patients undergoing ICSI with donated oocytes as a sperm processing add-on., (Copyright © 2021 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Two hundred and eighty-six isolates from human clinical samples were identified between 1996 and 2019 as belonging to 8 families, 19 genera and 88 species of Actinobacteria . The most identified genera were Streptomyces (182 strains from 45 species), Actinomadura (29 strains, 5 species), Nocardiopsis (21 strains, 6 species) and Dietzia (18 strains, 5 species). The rest of the identified genera (15) contained 27 species with 36 isolates. Of the species studied, only 13/88 had been documented previously as isolates from clinical samples, and in some cases, as true pathogens. In this sense, a literature review of the species found in infections or in clinical samples without clear involvement in pathology has been carried out. Finally, the susceptibility to 8 antimicrobial agents has been studied. Streptomyces showed high resistance (80.8%) against cefotaxime and cotrimoxazole (55.5%), and no isolate resistance to amikacin and linezolid have been found. Lower percentages of resistance have been found in other genera, except in Dietzia (100% against cotrimoxazole and 44.4% against erythromycin). The greatest resistance in these genera was to cotrimoxazole (29.8) and erythromycin (27,9%), and no resistance to linezolid has been found in these genera. In Microbispora, Nonomuraea and Umezawaea , no resistant isolates have been found against any antibiotic studied. Only 3/104 isolates were resistant to amikacin in Amycolatopsis , Crossiella , and Micromonosopora. One isolate of Amycolatopsis was resistant to imipenem., (© 2021 The Authors.)

Research Question: Does late-follicular phase progesterone elevation have a deleterious effect on embryo euploidy, blastocyst formation rate and cumulative live birth rates (CLBR)?, Design: A multicentre retrospective cross-sectional study including infertile patients aged 18-40 years who underwent ovarian stimulation in a gonadotrophin-releasing hormone antagonist protocol and preimplantation genetic testing for aneuploidies (PGT-A) followed by a freeze-all strategy and euploid embryo transfer between August 2017 and December 2019. The sample was stratified according to the progesterone concentrations on the day of trigger: normal (≤1.50 ng/ml) and high (>1.50 ng/ml). Moreover, sensitivity analyses were performed to determine whether different conclusions would have been drawn if different cut-offs had been adopted. The primary outcome was the embryo euploidy rate. Secondary outcomes were the blastocyst formation rate, the number of euploid blastocysts and CLBR., Results: Overall 1495 intracytoplasmic sperm injection PGT-A cycles were analysed. Late-follicular phase progesterone elevation was associated with significantly higher late-follicular oestradiol concentrations (2847.56 ± 1091.10 versus 2240.94 ± 996.37 pg/ml, P < 0.001) and significantly more oocytes retrieved (17.67 ± 8.86 versus 12.70 ± 7.00, P < 0.001). The number of euploid embryos was significantly higher in the progesterone elevation group (2.32 ± 1.74 versus 1.86 ± 1.42, P = 0.001), whereas the blastocyst formation rate (47.1% [43.7-50.5%] versus 51.0% [49.7-52.4%]), the embryo euploidy rate (48.3% [44.9-51.7%] versus 49.1% [47.7-50.6%], the live birth rate in the first frozen embryo transfer (34.1% versus 31.1%, P = 0.427) and CLBR (38.9% versus 37.0%, P = 0.637) were not significantly different between the two groups., Conclusions: Euploidy rate and CLBR do not significantly differ among PGT-A cycles with and without late-follicular progesterone elevation in a freeze-all approach., (Copyright © 2021. Published by Elsevier Ltd.)

Research Question: Does the position of the euploid blastocyst in the uterine cavity upon transfer, measured as distance in millimetres (mm) from the fundus (DFF) to the air bubble, influence implantation potential?, Design: A total of 507 single/double euploid frozen embryo transfer (FET) cycles at blastocyst stage were included retrospectively between March 2017 and November 2018 at a single centre. The patients were on average 33.3 years old. The FET were performed in natural cycles (n = 151) or hormone replacement therapy cycles (n = 356)., Results: Of the 507 transfers, 370 (73.0%) resulted in a pregnancy, defined as human chorionic gonadotrophin concentration over 15 mIU/ml, and 341 (67.3%) in a clinical pregnancy, with an implantation rate of 62.0% and ongoing pregnancy rate of 59.6% (302/507). When comparing the number of embryos transferred, the pregnancy rate, clinical pregnancy rate and ongoing pregnancy rate were significantly higher after double-embryo transfer (DET) (P = 0.002: P < 0.001 and P = 0.002). The quality of the blastocyst in the single-embryo transfer group had a positive effect on the pregnancy rate (A versus B, P = 0.016; A versus C, P = 0.003) and clinical pregnancy rate (A versus C, P = 0.013). After performing a multivariate logistic regression analysis to consider the effect of all explanatory variables, a negative effect between DFF and pregnancy (P = 0.001), clinical pregnancy (P = 0.001) and ongoing pregnancy (P = 0.030) was found. When all variables remained constant, an increase of 1 mm of DFF changed the odds of pregnancy by 0.882, of clinical pregnancy by 0.891 and of ongoing pregnancy by 0.925. No significant effect of DFF was found on the miscarriage outcome (P = 0.089)., Conclusions: The depth of blastocyst replacement inside the uterine cavity may influence the pregnancy, clinical pregnancy and ongoing pregnancy rates and should be considered as an important factor to improve the success of IVF cycles., (Copyright © 2021 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Does time since vasectomy (as obstructive interval) and the presence of different male comorbidities adversely affect the likelihood of achieving a newborn for vasectomized males undergoing testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI)?, Design: This retrospective study included 364 couples with vasectomized males undergoing TESE-ICSI cycles with autologous oocytes at IVI Valencia. The main outcome was live birth rate (LBR). Subjects were divided according to the male risk factor evaluated into quartiles (obstructive interval, body mass index [BMI]) or groups (hypertension, diabetes mellitus, dyslipidaemia). The reproductive outcomes were calculated per embryo transfer, per ovarian stimulation completed, and per couple., Results: The average obstructive interval was 11.3 years. The LBR was 34.4% (95% CI 30.1-38.6) per embryo transfer, 27.8% (95% CI 24.1-31.5) per ovarian stimulation and 46.2% (95% CI 41.8-51.3) per couple. When considering obstructive interval, a significantly lower LBR per couple (P = 0.04) was found in the group with the longest obstruction time: Q1 42.1% (95% CI 33.5-50.7), Q2 49.1% (95% CI 36.1-62.1), Q3 56.3% (95% CI 46.7-65.9) and Q4 37.2% (95% CI 26.5-47.9) but the cumulative live birth rate (CLBR) was not affected (P = 0.63). LBR per ovarian stimulation of males with hypertension was significantly lower (P = 0.04) than healthy males: 13.5% (95% CI 2.5-24.5) and 28.6% (95% CI 24.7-32.5), respectively. The group of diabetic vasectomized males had a significantly higher CLBR (P = 0.02). The remaining risk factors assessed (smoking, dyslipidaemia and a high BMI) did not affect LBR compared with their healthy counterparts., Conclusion: Time since vasectomy appears to negatively influence the LBR when assessed per couple. The CLBR was not affected by the obstructive interval or the presence of other male comorbidities apart from diabetes, which had a significant effect., (Copyright © 2021 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Do donor spermatozoa improve IVF outcomes after first oocyte donation failure?, Design: Retrospective, multicentre study including couples undergoing oocyte donation cycles using autologous or donor spermatozoa after a failed first attempt. Male partners were further characterized as normozoospermic or oligoasthenoteratospermic, i.e. fewer than 5 million motile progressive spermatozoa in the ejaculate. The main outcomes measured were live birth rate (LBR) per embryo transfer, LBR per number of embryos transferred, and cumulative LBR (CLBR) considering oocytes consumed in the previous donation cycles., Results: Analysis comprised 6065 cycles of oocyte donation failure; among these, subgroup analyses by sperm quality comprised 4113 cycles with severe male factor and 1150 cycles with suboptimal/normal spermatozoa. Sperm replacement in the first cycle after failure increased LBR per embryo transfer (OR 2.21, 95% CI 1.7-2.8, P < 0.001) and per number of embryos transferred (OR 2.46, 95% CI 1.9-3.1, P < 0.001) for normospermic and oligoasthenoteratospermic men. Replacement by the third cycle after failure was less beneficial (LBR per embryo transfer: OR 1.35, 95% CI 0.9-2.1, P = 0.16; LBR per embryos transferred: OR 1.33, 95% CI 0.9-2.0, P = 0.186). Kaplan-Meier curves of CLBR per oocyte fertilized with autologous or donor spermatozoa were statistically different (P < 0.001) and demonstrate how each additional oocyte may affect success based on sperm source (donor/autologous)., Conclusions: Donor spermatozoa improved outcomes when used after an initial failed oocyte donation cycle. The CLBR curves can be used to determine the cumulative chances of live birth using either autologous or donor spermatozoa, providing guidance on when to replace spermatozoa., (Copyright © 2021 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

The Tuberous Sclerosis Complex (TSC) protein complex (TSCC), comprising TSC1, TSC2, and TBC1D7, is widely recognised as a key integration hub for cell growth and intracellular stress signals upstream of the mammalian target of rapamycin complex 1 (mTORC1). The TSCC negatively regulates mTORC1 by acting as a GTPase-activating protein (GAP) towards the small GTPase Rheb. Both human TSC1 and TSC2 are important tumour suppressors, and mutations in them underlie the disease tuberous sclerosis. We used single-particle cryo-EM to reveal the organisation and architecture of the complete human TSCC. We show that TSCC forms an elongated scorpion-like structure, consisting of a central "body", with a "pincer" and a "tail" at the respective ends. The "body" is composed of a flexible TSC2 HEAT repeat dimer, along the surface of which runs the TSC1 coiled-coil backbone, breaking the symmetry of the dimer. Each end of the body is structurally distinct, representing the N- and C-termini of TSC1; a "pincer" is formed by the highly flexible N-terminal TSC1 core domains and a barbed "tail" makes up the TSC1 coiled-coil-TBC1D7 junction. The TSC2 GAP domain is found abutting the centre of the body on each side of the dimerisation interface, poised to bind a pair of Rheb molecules at a similar separation to the pair in activated mTORC1. Our architectural dissection reveals the mode of association and topology of the complex, casts light on the recruitment of Rheb to the TSCC, and also hints at functional higher order oligomerisation, which has previously been predicted to be important for Rheb-signalling suppression., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing financial interests., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Research Question: Does ovarian stimulation for oocyte vitrification affect disease-free survival and overall survival rates in women with early breast cancer?, Design: This cohort study included 259 patients with early breast cancer; 148 patients underwent ovarian stimulation, whereas 111 patients did not. Patients were treated between January 2008 and December 2016. To calculate the disease-free survival time and overall survival rate, the time of definitive surgery was defined as the starting point. The follow-up was conducted up to 5 years., Results: Exposed and non-exposed groups were comparable in tumour, node and metastases classification, Nottingham grade, hormonal receptor status, tumour molecular phenotype, histology and pathology stage. The exposed group was younger than the non-exposed. Recurrences occurred in 9/148 women (6.1%) in the exposed group and 15/111 women (13.5%) in the non-exposed group, with no significant difference. The mean disease-free survival time was 63.9 months (95% confidence interval [CI]: 61.5-66.4) in the exposed group and 60.6 months (95% CI: 56.9-64.2) in the non-exposed, with no significant difference (log-rank [Mantel-Cox] test). Overall survival rates were comparable; 2/148 (1.4%) and 4/111 (3.6%) patients died, in exposed and non-exposed groups, respectively, during the period analysed. Mean overall survival times were 67.2 months (95% CI: 66.2-68.2) in the exposed group and 65.9 months (95% CI: 64.0-67.9) in the unexposed, with no significant difference (log-rank [Mantel-Cox] test)., Conclusions: This study suggests that ovarian stimulation in patients with early-stage breast cancer is safe in the long term., (Copyright © 2019 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Research Question: Can gonadotrophin releasing hormone (GnRH) antagonist be used in egg donation recipients with ovulatory cycles for the purpose of achieving synchronization between the donor´s and recipient´s cycle?, Design: Prospective randomized controlled trial to compare 7-day dosage of GnRH antagonist for endometrial priming in an oocyte donation programme with a single dose of long-acting GnRH agonist. A total of 563 women were randomized in a private single centre, and 473 women underwent embryo transfer. Ongoing pregnancy rate was the primary end point. Analysis was adjusted for embryonic stage at the time of embryo transfer; data collected included days on the waiting list; number of fresh-vitrified oocytes collected; and oocyte donor´s age at the time of retrieval., Results: No statistically significant differences were found between groups in per intention-to-treat analysis: adjusted OR 1.42 (CI 0.97 to 2.09); per treatment received: adjusted OR 1.43 (CI 0.97 to 2.09); per embryo transfer: adjusted OR for ongoing pregnancy rate 1.47 (CI 1.01 to 2.13), P = 0.047., Conclusions: For women with ovulatory cycles undergoing oocyte donation, the outcomes are similar between GnRH antagonist and down-regulated hormone replacement protocols., (Copyright © 2018. Published by Elsevier Ltd.)

One hundred thirty-six isolates, 88 human and 48 environmental, that met the requirements to belong to the genus Paenibacillus were identified using a polyphasic taxonomic approach known as 16S rRNA plus phenotypic traits. Thirty-seven Paenibacillus species were identified; some had not been previously reported from clinical samples. The main species were P. pabuli (13 isolates), P. provencensis (11), P. phoenicis (9) and P. lautus (8). P. pabuli (11/13) and P. provencensis (8/11) were mainly environmental isolates, while P. phoenicis (9/9) and P. lautus (6/8) were mainly human isolates. Despite the difficulties in assigning to human Paenibacillus isolates a role as a pathogen or contaminant, here 25% of the isolates were involved in true infections, especially in those cases that affected abscesses, wound exudates, ocular infections and diverse fluids. In addition, 15 isolates were identified as 11 'Candidatus' to a new species, all of them from human specimens except one that was obtained from laboratory air . The antimicrobial susceptibility testing showed 95.6% of isolates were resistant to ampicillin, 44% were resistant to cotrimoxazole, 20 to 30% were resistant to cefotaxime and vancomycin and 13% were resistant to rifampicin and erythromycin.

The influence of aberrant sperm DNA methylation on the reproductive capacity of couples has been postulated as a cause of infertility. This study compared the DNA methylation of spermatozoa of 19 fertile donors and 42 infertile patients using the Illumina 450K array. Clustering analysis of methylation data arranged fertile and infertile patients into two groups. Bivariate clustering analysis identified a differential distribution of samples according to the characteristics of seminogram and age, suggesting a possible link between these parameters and specific methylation profiles. The study identified 696 differentially methylated cytosine-guanine dinucleotides (CpG) associated with 501 genes between fertile donors and infertile patients. Ontological enrichment analysis revealed 13 processes related to spermatogenesis. Data filtering identified a set of 17 differentially methylated genes, some of which had functions relating to spermatogenesis. A significant association was identified between RPS6KA2 hypermethylation and advanced age (P = 0.016); APCS hypermethylation and oligozoospermia (P = 0.041); JAM3/NCAPD3 hypermethylation and numerical chromosome sperm anomalies (P = 0.048); and ANK2 hypermethylation and lower pregnancy rate (P = 0.040). This description of a set of differentially methylated genes provides a framework for further investigation into the influence of such variation in male fertility in larger patient cohorts., (Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Background: COPD is a frequent severe illness that increasingly affects females. Gender inequalities have been reported in COPD care., Objective: To analyze decision-making in primary care for men and women with identical COPD as a function of the gender of the family physician (FP)., Methods: Cross-sectional, multicenter study in 457 Andalusian FPs, using a self-administered vignette-based questionnaire on COPD featuring a male or female patient, with four variables on clinical reasoning: "tobacco as most important risk factor (RF)", "ordering of spirometry", "COPD as most likely diagnosis", and "referral". Multilevel logistic regression analysis., Results: Response rate was 67.4% (308/457). In analysis of the four FP gender-patient gender dyads, tobacco was more frequently considered as priority RF for the man than for the woman in the vignette by female (95.6%vs.67.1%) and male (79.8%vs.62.5%) FPs. COPD was more frequently the most likely diagnosis for the man versus woman by female (84.4%vs.49.9%) and male (78.5%vs.57.8%) FPs. Male FPs more frequently ordered spirometry for the man versus woman (68.1%vs.46.8%). There were no differences in referral between male and female patients. Male FPs were more likely than female FPs to consider tobacco as priority RF for the man (p = 002). Female FPs were more likely than male FPs to refer the man (22.5%vs.8%)., Conclusions: There may be gender inequalities in primary care for COPD in our setting. Diagnostic and therapeutic efforts appear lower in female patients. Male and female FPs only differed in care of the male patient, indicating FP gender-patient gender interaction., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Species of the Burkholderia cepacia complex are associated with opportunistic infection in patients with cystic fibrosis. For years now, B. multivorans and B. cenocepacia have been the most frequently isolated species within the complex in such patients. However, between 2008 and 2012, the overall incidence of these species in Spain (17.7% and 12.5% respectively) was overtaken by that of B. contaminans (36.5%). The population structure of B. contaminans isolates from Spanish patients with cystic fibrosis was analysed using multilocus sequence typing and pulsed-field gel electrophoresis (PFGE). Three major known sequence types (ST102, ST404 and ST482) and a new one (ST771) were identified among 59 isolates. In addition, PFGE detected 17 pulsotypes. Susceptibility to antibiotics was examined using the Etest. Cotrimoxazole and ceftazidime were the most active antibiotics against B. contaminans, inhibiting growth in 88% and 86% of the isolates, respectively. In addition, this species showed less resistance to most of the antibiotics tested than did either B. multivorans or B. cenocepacia isolates recovered from similar Spanish patients., (Copyright © 2014 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Because of the different intrinsic characteristics of the classic IVF and intracytoplasmic sperm injection (ICSI) techniques, the timing of zygote development can be influenced by the method of fertilization. However, there is no information about the relevance of the insemination procedure on embryo-quality parameters as measured through their developmental dynamics. The aim of this work was to determine if the insemination technique, IVF or ICSI, influences embryo developmental kinetics by examining 1203 embryos from 178 couples undergoing oocyte donation with IVF or ICSI. Using time-lapse information, this work calculated several developmental kinetic variables, from pronuclear fading (PNF) to expanded blastocyst, and also the proportion of optimal embryos in a best time range with a predicted higher implantation potential. Embryo development after ICSI was slightly faster than after IVF; however, when PNF, rather than time of insemination, was established as t0, the differences between the two procedures disappeared. The percentage of optimal embryos showed a trend towards higher values in IVF-derived embryos; however, the difference was not statistically significant. With these results and through the time-lapse monitoring system, it is concluded that it is the fertilization method which determines embryo developmental kinetics if insemination time is used as the starting point. A key step in assisted reproduction is the assessment of oocyte and embryo viability to determine the embryo(s) most likely to implant. Current embryo assessment strategies in clinical settings largely rely on embryo morphology and cleavage rates, and although these systems have been successful in improving pregnancy rates, their precision is far from ideal as they are based on visual information. In contrast, automated image analysis may add objectivity to the process of embryo selection and consequently, lead to an improvement in the implantation rates. Timing of zygote development can be influenced by the method of fertilization or by in-vitro culture conditions, so it has been suggested that the fertilization procedure influences the length of time elapsed between fertilization and the first cleavage. In this report, we show the results from using a time-lapse monitoring system to determine the timing of key events during embryo development both in IVF and ICSI. Due to the different intrinsic characteristics of the classic IVF and ICSI techniques, the selection of a critical time point is essential so as to maximize the differences between the two methods. For that reason, we searched for evidence in the data obtained from the image analysis for a link connecting embryo cleavage and the fertilization technique and also to find whether the kinetic of development derived from classic IVF or ICSI is also related to a predicted higher implantation., (Copyright © 2013. Published by Elsevier Ltd.)

During follicular growth, the follicle is exposed to an almost ever-changing composition of isoforms of FSH and LH, which causes a number of different and divergent biological effects. Through a time-lapse system, embryo kinetics were examined following the use of FSH only (recombinant FSH, rFSH) and gonadotrophins containing LH activity (human menopausal gonadotrophin, HMG, and FSH+HMG) in oocyte donors. No significant differences were seen between the three groups (for rFSH, HMG and rFSH+HMG, t2 was 27.8h, 27.9h and 27.5h respectively). Moreover, although embryos obtained with rFSH showed an increase in the proportions of optimal timings of development, the differences observed were not significant, as shown by the percentages of embryos inside/outside these kinetic variables. In contrast, for gonadotrophin dosage and oestradiol concentration, this study observed differences in embryo development kinetics for some of the variables evaluated, which allowed the description of an optimal range of gonadotrophin dosage and oestradiol concentration. However, these kinetic differences did not translate into important distinctions in the proportion of optimal embryos with a higher implantation potential., (Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Noninvasive markers of embryo quality are being sought to improve IVF success. The present study aimed to discover possible associations between embryo division kinetics in the cleavage stage, the subsequent ability of human embryos to reach the blastocyst stage and the resulting blastocyst morphology. A retrospective cohort study analysed 834 embryos from 165 oocyte donation couples using a time-lapse monitoring system that allowed the recording of the exact timings for key events related to embryo development. Timing parameters were categorized into four quartiles. The probability of an embryo developing to a blastocyst was linked to a strict chronology of development. To further evaluate the relationships between these morphokinetic parameters and subsequent blastocyst formation, the ensuing blastocyst morphology was compared with a viability score based on a hierarchical classification of the cleavage-stage morphokinetic parameters. It is concluded that the kinetics of early embryo development and the potential for human embryos to develop to the blastocyst stage on day 5 are closely related and that time-lapse-based evaluation of the exact timing of early events in embryo development is a promising tool for the prediction of blastocyst formation and quality according to the proposed model., (Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Accumulation of oocytes from several ovarian stimulation cycles is currently possible using novel vitrification technologies. This strategy could increase the inseminated cohort, creating a similar situation to normoresponders. This study included 242 low-responder (LR) patients (594 cycles) whose mature oocytes were accumulated by vitrification and inseminated simultaneously (LR-Accu-Vit) and 482 patients (588 cycles) undergoing IVF/embryo transfer with fresh oocytes in each stimulation cycle (LR-fresh). Drop-out rate in the LR-fresh group was >75%. The embryo-transfer cancellation per patient was significantly lower in the LR-Accu-Vit group (9.1%) than the LR-fresh group (34.0%). Live-birth rate (LBR)/patient was higher in the LR-Accu-Vit group (30.2%) than the LR-fresh group (22.4%). Cumulative LBR/patient was statistically higher in the LR-Accu-Vit group (36.4%) than the LR-fresh group (23.7%) and a similar outcome was observed among patients aged ⩾40years (LR-Accu-Vit 15.8% versus LR-fresh 7.1%). The LR-Accu-Vit group had more cycles with embryo cryopreservation (LR-Accu-Vit 28.9% versus LR-fresh 8.7%). Accumulation of oocytes by vitrification and simultaneous insemination represents a successful alternative for LR patients, yielding comparable success rates to those in normoresponders and avoiding adverse effects of a low response. The accumulation of oocytes from several ovarian stimulation cycles is currently possible with the aid of novel vitrification technologies. This strategy could be useful for low-responder patients, contributing to increase the inseminated cohort and creating a similar situation as in normal responders. According to the results presented herein (higher live-birth rate per patient treated), this strategy represents a successful alternative for low-responder patients, yielding comparable success rates to those in normal responders and avoiding the adverse effects of a low response., (Copyright © 2012 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

A prospective study was performed to assess the impact of sperm DNA fragmentation on the outcome of IVF with own or donated oocytes. The study population included 178 couples (62 cycles of IVF, 116 of intracytoplasmic sperm injection (ICSI)) with own (n=77) and donor (n=101) oocytes. DNA fragmentation was evaluated by TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling assay. Correlation between DNA damage to oocyte fertilization, embryo quality and clinical pregnancy, implantation and miscarriage rates was evaluated. DNA fragmentation was not related to fertilization rates in either IVF (r=0.08) or ICSI (r=-0.04) cycles. DNA fragmentation was similar in patients with <50% embryo utilization rate compared with ≥50%, in cancelled and in embryo transfer cycles and in miscarriages and in successful deliveries. Moreover, DNA fragmentation was similar in pregnant and non-pregnant women as well as in IVF with own or donor oocytes. In the multivariable analysis, the odds ratio of DNA after controlling by age was 1.0. Using a 36% sperm fragmentation threshold, results did not vary. It is concluded that DNA damage was not related to outcomes of IVF or ICSI with own or donor oocytes., (Copyright © 2011 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Basic sperm analysis is limited as a method of estimating pregnancy. This study’s objective was use of microarray technology to differentiate the gene expressions of spermatozoa that achieved pregnancy in an intracytoplasmic sperm injection (ICSI)cycle in an oocyte donation programme with those that did not achieve pregnancy. A study of nested cases and controls was designed to evaluate fresh and frozen spermatozoa from infertile males undergoing ICSI with donor oocytes. The global genome expression of pooled samples from each group (achieving pregnancy versus those that didn’t, from fresh or frozen spermatozoa)was compared using microarray analysis. The level of expression of some of the transcripts from fresh spermatozoa was shown to differ for those that achieved pregnancy versus those that didn’t. Additionally, exclusively expressed transcripts were identified for both outcome groups. Analysis of frozen spermatozoa didn’t reveal differential expression, but exclusively expressed transcripts were detected. Lists of the transcripts were systematically analysed using different databases in order to provide information about them and their relationship with male fertility. The results revealed profound differences between the expression profiles of spermatozoa that resulted in pregnancy versus those that didn’t. These differences may explain ICSI failure associated with male factor infertility., (Copyright © 2010 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Telomere length and sperm DNA fragmentation were determined in sperm samples from 27 patients, using a quantitative PCR (Q-PCR) assay and the Sperm Chromatin Dispersion (SCD) test, respectively. Comparisons of the samples before and after swim-up processing demonstrated that this procedure selects a sperm population with longer average telomere size and lower frequency of sperm cells with fragmented DNA., (Copyright 2010 Elsevier B.V. All rights reserved.)

The use of gonadotrophin-releasing hormone (GnRH) agonists for triggering ovulation remains controversial. The primary objective of this study was to evaluate the incidence of ovarian hyperstimulation syndrome (OHSS) following GnRH agonist versus recombinant human chorionic gonadotrophin (HCG) as methods for triggering ovulation. A second aim was to compare the clinical outcome and embryo quality according to the two procedures. The cycle characteristics of 100 oocyte donors undergoing ovarian stimulation and IVF outcomes of their 100 oocyte recipients were analysed. Donors were prospectively randomized into two groups on the last day of ovarian stimulation: Group I received a single bolus of 0.2 mg of triptorelin and Group II received 250 microg of recombinant HCG. No differences were observed in the number of oocytes retrieved or in the proportion of metaphase II oocytes between the groups. The OHSS rate was higher in donors that received recombinant HCG ( P = 0.003). Moreover, there was no significant difference between IVF parameters and outcome in the two groups. In conclusion, a GnRH agonist effectively triggers the final oocyte maturation in oocyte donors without negatively affecting implantation, pregnancy or miscarriage rates. Moreover, this regime effectively eliminates the risk of OHSS in this group of women.

Semen analysis, as stated by the World Health Organization, is the only accepted tool to assess male fertility. However its predictive value to assess male capacity to initiate a pregnancy is limited. With the introduction of IVF (especially via intracytoplasmic sperm injection), infertility caused by diminished sperm production is frequently solved, but knowledge of sperm physiology remains very poor. Moreover, a percentage of males with apparently normal semen are unable to impregnate healthy women. Therefore, improvements in the diagnostic tools to assess male fertility potential are necessary. The aim of this review is to describe sperm molecular factors implicated in male fertility, demonstrated by their role in sperm physiology, the molecular differences found between fertile and infertile males, or by their influence on the results obtained in assisted reproduction treatments in terms of embryo quality and pregnancy achievement. From a search and objective evaluation of the currently available evidence, it is concluded that there is no unique factor able to predict male fertility, but several molecular factors are involved in sperm function and can potentially be considered as fertility markers. In this context, a complex molecular tool designed to analyse a battery of parameters seems to be necessary.

There has been an increasing tendency to delay parenthood in developed countries in recent years, and there is not enough information available regarding the effect of this on fertility. The aim of this work was to determine the role of paternal age on the outcome of assisted reproduction. A retrospective study was designed comprising a total of 2204 intrauterine insemination (IUI) cycles, 1286 IVF cycles and 1412 IVF cycles with donated oocytes during the period 2000 to 2006. Male mean age was 34.3 years (range 25-56) for IUI, 34.8 years (range 19-62) for IVF and 41.10 years (range 25-71) for ovum donation cycles. Statistics revealed no differences regarding pregnancy and miscarriage rates when the results were compared among age groups. In standard IVF and ovum donation cycles there was no clear association between embryo quality and paternal age. There was no significant relationship between male age and implantation rate. So far this is the largest study concerning the relevance of male age in assisted reproduction. As confirmed by the present data, the effect of the age of the male in the range studied is irrelevant. This finding contributes to the information that can be provided to infertile couples.

Acetone and diazotized anthranilic acid react in alkaline solution, giving a fluorescent intermediate that can be measured at excitation and emission wavelengths of 305 and 395 nm, respectively. Based on this, a fluorimetric flow-injection method is proposed for the determination of acetone in aqueous solution. Under the proposed conditions, acetone can be detected at concentrations higher than 8 x 10(-7)M, with a linear application range from 1 x 10(-6) to 2 x 10(-4)M and an R.S.D. of 2.7% (1.0 x 10(-5)M, n=10). A sampling frequency of 24h(-1) is achieved. Some potentially interfering species are investigated.

The possibility of revealing the identity of gamete donors may change the decision of a donor to collaborate with infertility clinics and patients. Previous experiences with patients and donors, as well as different cultural viewpoints in northern and southern Europe, are presented.

Nine coordination compounds of Cu(II) and Co(II) with Ciprofloxacin (HCp) and Enoxacin (HEx) as ligands have been prepared and characterized. Single crystal structural determinations of [Cu(HCp)2(ClO4)2].6H2O (1) and [Co(HEx)2(Ex)]Cl.2CH(3)OH.12H2O (4) are reported. The crystal of 1 is composed of [Cu(HCp)2(ClO4)2] units with the two perchlorate anions semicoordinated, and uncoordinated water molecules. The copper ion, at a crystallographic inversion centre, is in a tetragonally distorted octahedral environment. The structure of 4 consists of cationic monomeric [Co(HEx)2(Ex)]+ units, chloride anions, and uncoordinated methanol and water molecules. The complex is six-coordinate, with a slightly distorted octahedral environment around the metal centre. Some complexes of ciprofloxacin and enoxacin were screened for their activity against several bacteria, showing activity similar to that of the corresponding free ligands. All compounds tested were more active against Gram-negative bacteria than against Gram-positive bacteria. Ciprofloxacin hydrochloride and its complexes were more active than enoxacin and its complexes. In addition, the bactericidal studies against Staphylococcus aureus ATCC 25923 reveal that one complex exhibits the "paradoxical effect" (diminution in the number of bacteria killed at high drug concentration), which has been described and related to the mechanism of action of quinolones, but three other complexes do not, suggesting different mechanisms of bactericidal action. The ability of Cu(HCp)2(NO3)2.6H2O to cleave DNA has been determined. The results show that the complex behaves as an efficient chemical nuclease with ascorbate/hydrogen peroxide activation. Mechanistic studies using different inhibiting reagents reveal that hydroxyl radicals are involved in the DNA scission process mediated by this compound.

Drugs facilitating GABAergic neurotransmission have been reported to block some behavioral actions of dopaminergic stimulation but not others. The present experiments were performed with the purpose to extend the range of behaviors in which the interaction between GABA and dopamine have been studied. The ability of the GABAB agonist baclofen and the GABA transaminase inhibitor sodium valproate to block the enhanced distractibility produced by amphetamine was evaluated in a procedure especially designed for analyzing drugs' effects on distractibility. Briefly, rats were trained to traverse a straight runway with a sucrose solution as reinforcement. Once the response had been acquired, an additional runway ending in an empty box was connected. The time spent investigating this additional runway is the measure of distractibility. Male rats treated with amphetamine, 1 mg/kg, displayed an increase of the time spent in the additional runway. Baclofen, 2.5 and 5 mg/kg, and sodium valproate, 100 and 200 mg/kg, had no effect on distraction behavior when administered alone. However, when these drugs were administered together with amphetamine, 1 mg/kg, they completely inhibited the effects of the stimulant on distractibility. These data show that distractibility is similar to discrimination learning with regard to the capacity of GABAergic drugs to block the effects of dopaminergic stimulation. It is different from locomotor activity, however, where GABAergic drugs are ineffective in this respect.