Candida auris in Intensive Care Setting: The First Case Reported in Portugal

Candida auris is an opportunistic human pathogen that has rapidly spread to multiple countries and continents and has been associated with a high number of nosocomial outbreaks. Herein, we report the first case of C. auris in Portugal, which was associated with a patient transferred from Angola to an ICU in Portugal for liver transplantation after a SARS-CoV-2 infection. C. auris was isolated during the course of bronchoalveolar lavage, and it was subjected to antifungal susceptibility testing and whole-genome sequence analysis. This isolate presents low susceptibility to azoles and belongs to the genetic clade III with a phylogenetic placement close to African isolates. Although clade III has already been reported in Europe, taking into account the patient's clinical history, we cannot discard the possibility that the patient's colonization/infection occurred in Angola, prior to admission in the Portuguese hospital. Considering that C. auris is a fungal pathogen referenced by WHO as a critical priority, this case reinforces the need for continuous surveillance in a hospital setting.

Increased Synaptic ATP Release and CD73-Mediated Formation of Extracellular Adenosine in the Control of Behavioral and Electrophysiological Modifications Caused by Chronic Stress

Increased ATP release and its extracellular catabolism through CD73 (ecto-5'-nucleotidase) lead to the overactivation of adenosine A_2A receptors (A_2AR), which occurs in different brain disorders. A_2AR blockade blunts mood and memory dysfunction caused by repeated stress, but it is unknown if increased ATP release coupled to CD73-mediated formation of extracellular adenosine is responsible for A_2AR overactivation upon repeated stress. This was now investigated in adult rats subject to repeated stress for 14 consecutive days. Frontocortical and hippocampal synaptosomes from stressed rats displayed an increased release of ATP upon depolarization, coupled to an increased density of vesicular nucleotide transporters and of CD73. The continuous intracerebroventricular delivery of the CD73 inhibitor α,β-methylene ADP (AOPCP, 100 μM) during restraint stress attenuated mood and memory dysfunction. Slice electrophysiological recordings showed that restraint stress decreased long-term potentiation both in prefrontocortical layer II/III-layer V synapses and in hippocampal Schaffer fibers-CA1 pyramid synapses, which was prevented by AOPCP, an effect occluded by adenosine deaminase and by the A_2AR antagonist SCH58261. These results indicate that increased synaptic ATP release coupled to CD73-mediated formation of extracellular adenosine contributes to mood and memory dysfunction triggered by repeated restraint stress. This prompts considering interventions decreasing ATP release and CD73 activity as novel strategies to mitigate the burden of repeated stress.

The need for longitudinal data on the value of fertility treatment for infertile patients' quality of life: A review and pilot study

Infertility threatens the life goal of parenthood and, hence, quality of life (QoL) of (wo)men, but the fertility clinic trajectory might be burdensome. This review of longitudinal studies and pilot longitudinal study examines the impact of the pre-in vitro fertilization (IVF) fertility clinic trajectory on patient-reported outcome measures (PROMs) for emotional well-being, including QoL. A publication found that the diagnostic workup decreases men's infertility-specific distress while publications disagree whether it decreases (wo)men's anxious and depressive reactions. Intrauterine insemination (IUI) was found to increase (wo)men's depressive reactions. Publications on infertility-specific, health-related, and overall QoL were missing. The pilot indicated that (wo)men's overall QoL is not affected by the diagnostic workup but is decreased by the time of the third IUI. Longitudinal studies on the impact of starting the fertility clinic trajectory on PROMs are needed as they are essential for patient-centered clinical decision-making and patient-centered policy-level decision-making.

Aβ1-42 peptides blunt the adenosine A2A receptor-mediated control of the interplay between P2X7 and P2Y1 receptors mediated calcium responses in astrocytes

The contribution of astrocytes to Alzheimer's disease (AD) is still ill defined. AD involves an abnormal accumulation of amyloid-β peptides (Aβ) and increased production of danger signals such as ATP. ATP can direct or indirectly, through its metabolism into adenosine, trigger adaptive astrocytic responses resulting from intracellular Ca2+ oscillations. AD also triggers an upregulation of astrocytic adenosine A2A receptors (A2AR), which blockade prevents memory dysfunction in AD. We now investigated how Aβ peptides affect ATP-mediated Ca2+ responses in astrocytes measured by fluorescence live-cell imaging and whether A2AR control astrocytic Ca2+ responses mediated by ATP receptors, mainly P2X7R and P2Y1R. In primary cultures of rat astrocytes exposed to Aβ1-42, ATP-evoked Ca2+ responses had a lower amplitude but a longer duration than in control astrocytes and involved P2X7R and P2Y1R, the former potentiating the later. Moreover, Aβ1-42 exposure increased protein levels of P2Y1R in astrocytes. A2AR antagonism with SCH58261 controlled in a protein kinase A-dependent manner both P2X7R- and P2Y1R-mediated Ca2+ responses in astrocytes. The interplay between these purinoceptors in astrocytes was blunted upon exposure to Aβ1-42. These findings uncover the ability of A2AR to regulate the inter-twinned P2X7R- and P2Y1R-mediated Ca2+ dynamics in astrocytes, which is disrupted in conditions of early AD.

O-089 The impact of sharing personalized IVF-prognoses: a randomized controlled trial

Study question

Are women less likely to expect unrealistic live birth rates (i.e. 100% or > 2x their personalized IVF-prognosis) if gynaecologists share personalized IVF-prognoses during embryo transfer?

Summary answer

Sharing IVF-prognoses results in 1/3 rather than 1/2 women expecting unrealistic live birth rates (p = 0.03), but their partners do not take their IVF-prognosis into account.

What is known already

IVF-patients know that average IVF-success rates are only around 30%, but this does not hold them back from expecting an IVF success-rate of around 59% from their own IVF-cycle. These unrealistic expectations cause frustration among clinic staff and seem to contribute to patient’s decision to discontinue IVF. Performant prognostic models can now calculate personalized IVF-prognoses, based on clinical and laboratory factors, but the impact of these models on the expectations and wellbeing of IVF-patients had yet to be examined by an RCT.

Study design, size, duration

As dictated by a-priori power calculation, 160 heterosexual couples having their 2nd-5th oocyte aspiration (2019-2021) were recruited to study minimally 128 randomized couples (computer; 1:1 allocation; drop-out=20%) on the day of fresh embryo transfer. On that day the attention-control group received an embryo photo and feedback on the number of cryopreserved embryos. The intervention group additionally received their embryo quality rating and personalized IVF-prognosis (complete IVF-cycle live birth rate, Devroe et al., BMJOpen, 2020).

Participants/materials, setting, methods

A total of 160 of 197 (81.2%) invited couples agreed to participate and 144 were randomized (72 per group; n = 16 not randomized as no embryo for transfer on day 3 or 5). Immediately after the embryo transfer and attention-control or intervention condition, women and their partners (independently) rated their expected IVF live birth rate on a numerical rating scale (0-100%) and filled out the ‘STAI-State-Anxiety Inventory’. Analysis was according to intention to treat principles.

Main results and the role of chance

Randomisation succeeded in distributing the background variables equally between the attention-control group (ACG) and intervention group (IG). Couples had a mean duration of infertility of 26 months (±14.6), a median of one previous oocyte aspiration (range: 1-4) and a mean personalized IVF prognosis of 29.7 (±16.2; range 3.3–75.5). The primary hypothesis was accepted: women of the intervention group, having received their personalized IVF-prognosis, were less likely to expect an unrealistic IVF-live birth rate of 100% or of twice as high as their personalized IVF-prognosis (IG: n = 23/69 or 33.3% vs. ACG: 34/66 or 51.522%; p = 0.03). A trend in the same direction was observed in men (IG: 26/63 or 41.27% vs. ACG: 34/60 or 56.67%; p = 0.09). Focussing on the subgroup of couples with a below average prognosis (<30%; n = 76), in which the hypothesised effect seems most likely, confirmed the intervention effect in women (p = 0.016) and the lack thereof in men (p = 0.15). Receiving the intervention during embryo transfer affected state anxiety immediately after the embryo transfer in women (IG: 39.5±10.0 vs. 39.5±10.1; p = 0.54) nor men (IG: 37.6±9.1 vs. 37.1±7.7; p = 0.41). The vast majority of patients would advise the feedback to others, irrespective of having received their personalized prognosis (women: p = 0.9; men p = 0.4).

Limitations, reasons for caution

This RCT was powered for analysing the primary outcome in the entire sample, but not for the subgroup analysis. Whether the effect of sharing personalized IVF-prognoses on women's expectations translates into an effect on IVF-discontinuation, and hence cumulative success rates, is currently followed up.

Wider implications of the findings

Clinics are advised to offer patients their personalized IVF-prognosis as this limits the likelihood of unrealistic expectations in women, without triggering anxious reactions. The proportion of women and men with unrealistic expectations, however, remained high and men did not respond to our feedback.

Trial registration number

NCT04169295

O-158 The evolution of the quality of life of women and men during the fertility clinic trajectory: a longitudinal survey

Study question

How does the overall quality of life (QoL) of infertile women and men evolve during the diagnostic workup and during intrauterine insemination (IUI)?

Summary answer

The diagnostic workup affects the overall QoL of neither women nor men but both partner’s QoL is diminished by the time of their third IUI.

What is known already

Overall quality of life (QoL) is increasingly acknowledged as the ultimate measure of health care quality. The WHO defines ‘overall QoL’ as an individual’s perception of their position in life in relation to their context, goals, expectations, standards and concerns. Infertility threatens the life goal of becoming parents. Value preference studies concluded that cost analyses should consider a decrement in women’s QoL for ‘being infertile with the desire for a child’. The short-term QoL costs or benefits of the fertility clinic trajectory, before potentially achieving the long-term benefit of a live birth, have yet to be examined.

Study design, size, duration

Two cohorts consulting a Belgian fertility clinic were studied longitudinally. Cohort 1 (C1) included 36 women and their partners (response rate 54%), who were surveyed before their first consultation (T1) and three months later, towards the end of their diagnostic workup (T2; 2017-2019). Cohort 2 (C2) included 23 women and their partners (response rate 64%), who were surveyed during their diagnostic workup (T1) and at the time of their third IUI (T2; 2020-2021).

Participants/materials, setting, methods

Dutch- or English-speaking heterosexual couples first consulting a fertility clinic were eligible. Overall QoL was assessed with the valid and reliable linear analogue scale (LAS; range: 1-100; the higher, the better QoL; Moons et al., Eur J Cardiovasc Prev Rehabil, 2006). Paired samples t-tests assessed the evolution in the overall QoL of women and of men. Linear models examined whether already being parents and male factor infertility affected change scores.

Main results and the role of chance

Women and men of both cohorts were on average in their early thirties and couples had tried to conceive naturally for, on average, 19 (C1) and 16 (C2) months. Most individuals (65.4% in C1; 87% in C2) did not yet parent a child. A considerate proportion of couples had been diagnosed with (amongst others) male factor infertility (34.6% in C1; 26.0% in C2).

The diagnostic workup did not affect the overall QoL of women (T1: 78.8±8.1 vs. T2: 75.8±9.7, p = 0.147) or men (T1: 80.8±7.9 vs. T2: 79.2±8.7, p = 0.206). The evolution in overall QoL throughout the diagnostic workup did not depend on parenthood status or male factor infertility (p > 0.05).

By the time of their third IUI, women’s overall QoL had diminished (T1: 80.9±9.9 vs. T2: 74.0±15.0, p = 0.018). This evolution was not affected by parenthood status or male factor infertility (p > 0.05). Similarly, men’s overall QoL had diminished by the time of their third IUI (T1: 82.0±7.2 vs. T2: 78.1±9.6, p = 0.042). This reduction in men’s QoL was not affected by parenthood status (p = 0.759) but was especially observed (p = 0.028) among men without male factor infertility (T1: 82.9±7.9 vs. T2: 77.0±11.0, p = 0.008).

Limitations, reasons for caution

The rather small sample sizes were sufficient for examining the effect on QoL of time and two potential determinants (parenthood status, male factor infertility) according to the rule of thumb of including minimally five individuals per variable. Recruitment is still ongoing to increase the power of these cohort studies.

Wider implications of the findings

Fertility nurses/midwives should inform couples pursuing their life goal of parenthood that the fertility clinic trajectory will require short-term sacrifices. The diagnostic workup affects the overall QoL of neither women nor men, but both partner’s overall QoL is slightly diminished by the time of their third unsuccessful intrauterine insemination.

Trial registration number

not applicable

Adenosine A2A receptors blockade attenuates dexamethasone-induced alterations in cultured astrocytes

Anxiety involves abnormal glucocorticoid signalling and altered glia-neuron communication in brain regions processing emotional responses. Adenosine A2A receptor (A2AR) blockade ameliorates mood and memory impairments by preventing synaptic dysfunction and astrogliosis. Since the glucocorticoid dexamethasone (DEX) can mimic early life-stress conditions, leading to anxiety-like behaviours, we now tested if A2AR blockade prevents alterations in the morphology and function of astrocytes exposed to DEX. Cultured astrocytes exposed to DEX exhibited an up-regulation of astrocytic markers (GFAP, connexin-43 and glutamine synthetase), as well as of A2AR. Moreover, DEX enhanced ATP and glutamate release and increased basal astrocytic Ca2+ levels. The selective A2AR antagonist SCH58261 prevented DEX-induced alterations in ATP release and basal Ca2+ levels but did not affect DEX-induced alteration of glutamate release and astrocytic markers. These findings suggest that alterations in astrocytes function, which might contribute to abnormal glucocorticoid brain signalling, are controlled by A2AR, and therefore, reinforce the relevance of A2AR as a potential therapeutic target to manage mood disorders.

O-166 A smartphone video clip on the patient journey to reduce patient’s anxiety: a randomized controlled trial

Study question

Can a smartphone video clip detailing the patient journey decrease the anxiety of women and men on the day of their first oocyte aspiration?

Summary answer

The video clip does not affect the anxiety of women but does reduce the anxiety of men on the day of couples’ first oocyte aspiration.

What is known already

Infertility and in vitro fertilisation (IVF) decrease the personal wellbeing of women and men. Couples shared that this contributed to their IVF discontinuation despite a good prognosis and reimbursement of IVF. Previous longitudinal studies confirmed that pre-IVF anxiety is associated with IVF discontinuation. Limiting treatment anxiety is, therefore, relevant for fertility patients and clinics. Studies from the field of reproductive medicine examining the effect of preparatory information on anxiety suggest that focussed interventions seem more effective than complex interventions. Several randomized controlled trials (RCTs) found that preparatory information movies reduce anxiety for out-patient cardiology procedures in women and men.

Study design, size, duration

This monocentric RCT randomized (1:1 allocation; computerized) 190 heterosexual couples about to start their first IVF cycle between care as usual (i.e. preparatory information session 1-3 months before IVF) and care as usual combined with a novel intervention during a 24 months recruitment period (2018-2020). The novel intervention is a 5-minute smartphone video clip detailing the patient journey on the day of oocyte aspiration, which was sent to both partners the day before oocyte aspiration.

Participants/materials, setting, methods

Upon arrival at a private fertility clinic for their first oocyte aspiration women and men independently filled out the ‘STAI-State anxiety inventory’ and the ‘infertility distress scale (IDS)’ and evaluated the novel intervention, if applicable. A minority of randomized couples didn’t comply with the standard IVF trajectory (n = 27) or didn’t fill out the questionnaires (n = 8). The data of 155 couples (76-79/group, a-priori sample size calculation requested minimally 76/group) was subjected to a modified intention-to-treat analysis.

Main results and the role of chance

Women and men were on average 33 and 35 years old, respectively. Couples had a mean duration of infertility of 27 months and 63 of them (41%) had tried intrauterine insemination. The background variables were equally distributed between the intervention (IG) and control group (CG). The video clip did not affect women’s anxiety on the day of oocyte aspiration (mean STAI-State score IG 42.7±8.1 vs CG 42.1±8.5, p = 0.67). However, men who watched the video clip were significantly less anxious than men who did not watch it (mean STAI-State score IG 35.8±6.4 vs CG 38.2±7.6, p = 0.04). Surprisingly, infertility-specific distress was higher among women and men who watched the video clip (mean IDS scores of 25.8±4.9 and 22.6±5.0, respectively), as compared to women (p = 0.05) and men (p = 0.02) who did not watch the video clip (mean IDS score 24.3±4.6 and 20.8±4.7, respectively). All women and men of the intervention group, except one woman, would recommend the video clip to friends and family going through IVF. The intervention and control group did not differ significantly regarding clinical pregnancy rate (31/76 vs. 29/79, p = 0.60) or miscarriage rate (2/76 vs. 3/79, p = 0.68) 12 weeks after their first oocyte aspiration.

Limitations, reasons for caution

Patients nor assessors were blinded and there was no attention control group. Selection bias is plausible although the participation rate was 89%. Assessing infertility-specific distress the day after watching the video clip was not optimal, as priming couples to feel infertility-specific distress short term is less problematic than longer term.

Wider implications of the findings

Providing additional procedural information is interesting for clinics as patients recommended the video clip and as it decreased men’s anxiety. A follow-up study should examine whether the video clip’s priming effect on infertility-specific distress lasts longer than only the day after and whether the video clip affects IVF discontinuation.

Trial registration number

NCT03717805

Analysis of Milk Using a Portable Potentiometric Electronic Tongue Based on Five Polymeric Membrane Sensors

A portable potentiometric electronic tongue (PE-tongue) was developed and applied to evaluate the quality of milk with different fat content (skimmed, semi-skimmed, and whole) and with different nutritional content (classic, calcium-enriched, lactose-free, folic acid–enriched, and enriched in sterols of vegetal origin). The system consisted of a simplified array of five sensors based on PVC membranes, coupled to a data logger. The five sensors were selected from a larger set of 20 sensors by applying the genetic algorithm (GA) to the responses to compounds usually found in milk including salts (KCl, CaCl₂, and NaCl), sugars (lactose, glucose, and galactose), and organic acids (citric acid and lactic acid). Principal component analysis (PCA) and support vector machine (SVM) results indicated that the PE-tongue consisting of a five-electrode array could successfully discriminate and classify milk samples according to their nutritional content. The PE-tongue provided similar discrimination capability to that of a more complex system formed by a 20-sensor array. SVM regression models were used to predict the physicochemical parameters classically used in milk quality control (acidity, density, %proteins, %lactose, and %fat). The prediction results were excellent and similar to those obtained with a much more complex array consisting of 20 sensors. Moreover, the SVM method confirmed that spoilage of unsealed milk could be correctly identified with the simplified system and the increase in acidity could be accurately predicted. The results obtained demonstrate the possibility of using the simplified PE-tongue to predict milk quality and provide information on the chemical composition of milk using a simple and portable system.

Crosstalk Between ATP-P2X7 and Adenosine A2A Receptors Controlling Neuroinflammation in Rats Subject to Repeated Restraint Stress

Depressive conditions precipitated by repeated stress are a major socio-economical burden in Western countries. Previous studies showed that ATP-P_2X7 receptors (P_2X7R) and adenosine A_2A receptors (A_2AR) antagonists attenuate behavioral modifications upon exposure to repeated stress. Since it is unknown if these two purinergic modulation systems work independently, we now investigated a putative interplay between P_2X7R and A_2AR. Adult rats exposed to restraint stress for 14 days displayed an anxious (thigmotaxis, elevated plus maze), depressive (anhedonia, increased immobility), and amnesic (modified Y maze, object displacement) profile, together with increased expression of Iba-1 (a marker of microglia “activation”) and interleukin-1β (IL1β) and tumor necrosis factor α (TNFα; proinflammatory cytokines) and an up-regulation of P_2X7R (mRNA) and A_2AR (receptor binding) in the hippocampus and prefrontal cortex. All these features were attenuated by the P_2X7R-preferring antagonist brilliant blue G (BBG, 45 mg/kg, i.p.) or by caffeine (0.3 g/L, p.o.), which affords neuroprotection through A_2AR blockade. Notably, BBG attenuated A_2AR upregulation and caffeine attenuated P_2X7R upregulation. In microglial N9 cells, the P_2X7R agonist BzATP (100 μM) or the A_2AR agonist CGS26180 (100 nM) increased calcium levels, which was abrogated by the P_2X7R antagonist JNJ47965567 (1 μM) and by the A_2AR antagonist SCH58261 (50 nM), respectively; notably JNJ47965567 prevented the effect of CGS21680 and the effect of BzATP was attenuated by SCH58261 and increased by CGS21680. These results provide the first demonstration of a functional interaction between P_2X7R and A_2AR controlling microglia reactivity likely involved in behavioral adaptive responses to stress and are illustrative of a cooperation between the two arms of the purinergic system in the control of brain function.

Trypanosoma cruzi tryparedoxin II interacts with different peroxiredoxins under physiological and oxidative stress conditions

Trypanosoma cruzi, the etiologic agent of Chagas disease, has to cope with reactive oxygen and nitrogen species during its life cycle in order to ensure its survival and infection. The parasite detoxifies these species through a series of pathways centered on trypanothione that depend on glutathione or low molecular mass dithiol proteins such as tryparedoxins. These proteins transfer reducing equivalents to peroxidases, including mitochondrial and cytosolic peroxiredoxins, TcMPx and TcCPx, respectively. In T. cruzi two tryparedoxins have been identified, TXNI and TXNII with different intracellular locations. TXNI is a cytosolic protein while TXNII due to a C-terminal hydrophobic tail is anchored in the outer membrane of the mitochondrion, endoplasmic reticulum and glycosomes. TXNs have been suggested to be involved in a majority of biological processes ranging from redox mechanisms to protein translation. Herein, a comparison of the TXNII interactomes under physiological and oxidative stress conditions was examined. Under physiological conditions, apart from the proteins with unknown biological process annotation, the majority of the identified proteins are related to cell redox homeostasis and biosynthetic processes, while under oxidative stress conditions, are involved in stress response, cell redox homeostasis, arginine biosynthesis and microtubule based process. Interestingly, although TXNII interacts with both peroxiredoxins under physiological conditions, upon oxidative stress, TcMPx interaction prevails. The relevance of the interactions is discussed opening a new perspective of TXNII functions.

Tibial derotational osteotomies in two neuromuscular populations: comparing cerebral palsy with myelomeningocele

PURPOSE

To review the outcomes of tibial derotational osteotomies (TDOs) as a function of complication and revision surgery rates comparing a cohort of children with myelodysplasia to a cohort with cerebral palsy (CP).

METHODS

A chart review was completed on TDOs performed in a tertiary referral centre on patients with myelodysplasia or CP between 1985 and 2013 in patients aged > 5 years with > 2 years follow-up. Charts were reviewed for demographics, direction/degree of derotation, complications and need for re-derotation. Two-sample T-tests were used to compare the characteristics of the two groups. Two-tailed chi-square tests were used to compare complications. Generalised linear logit models were used to identify independent risk factors for complication and re-rotation.

RESULTS

The 153 patients (217 limbs) were included. Average follow-up was 7.83 years. Overall complication incidence was 10.14%, including removal of hardware for any reason, with a 4.61% major complication incidence (fracture, deep infection, hardware failure). After adjusting for gender and age, the risk of complication was not statistically significantly different between groups (p = 0.42) nor was requiring re-derotation (p = 0.09). The probability of requiring re-derotation was 31.9% less likely per year increase in age at index surgery (p = 0.005).

CONCLUSION

With meticulous operative technique, TDO in children with neuromuscular disorders is a safe and effective treatment for tibial torsion, with an acceptable overall and major complication rate. The risk of re-operation decreases significantly in both groups with increasing age. The association between age at initial surgery and need for re-derotation should help guide the treatment of children with tibial torsion.

Prevalence of enamel defects and association with dental caries in preschool children

AIM

This was to evaluate the prevalence of the developmental defects of enamel (DDE) in primary teeth and its association with dental caries.

METHODS

A cross-sectional study with a randomised representative sample was carried out with 1101 children aged 2-5 years enrolled in public preschools (50% prevalence of DDE in primary teeth, a standard error of 3%, and a confidence level of 95%). Three calibrated dentists (K > 0.62) performed clinical examination. Data collected were: sex, age, DDE (Modified DDE Index) and dental caries (WHO). Descriptive analysis, Chi-square test and multinomial logistic regression were applied for data analysis.

RESULTS

Among children, 565 (51.3%) were boys; mean age was 3.7 (±0.9 years). The prevalence of enamel defect was 39.1%; the prevalence of diffuse opacities, demarcated opacities and enamel hypoplasia was 25.3, 19.1 and 6.1%, respectively. The prevalence of dental caries was 31.0%, with mean def-t 1.14 (±2.44). Primary teeth with enamel hypoplasia had three times the odds of having dental caries than those with absence of enamel defects (OR = 3.10; 95% CI: 1.91, 5.01).

CONCLUSION

The presence of enamel defects was moderate and associated with dental caries.

Conversion From Twice-Daily to Once-Daily Tacrolimus in Stable Kidney Graft Recipients

INTRODUCTION

Immunosuppression has a pivotal role in kidney transplantation. The new prolonged-release formulation of tacrolimus was developed to provide a more convenient once-daily dosing to improve patient adherence.

METHODS

We selected 60 stable kidney transplant recipients who underwent tacrolimus conversion in our unit. Conversion was made on a 1 mg:1 mg basis in 66.7% of patients (n = 40) and on a 1 mg:1.1 mg basis in the remaining 33.3% (n = 20). Clinical and analytical data at conversion and postconversion was analyzed retrospectively to evaluate the efficacy and safety of conversion from tacrolimus twice-daily to once-daily formulation.

RESULTS

A significant reduction in tacrolimus blood levels requiring an increase in tacrolimus daily dose was observed postconversion. Postconversion tacrolimus blood level reduction >25% was significantly higher in the conversion group 1 mg:1 mg basis (P = .004). In patients converted 1 mg:1 mg, female sex and higher tacrolimus level at conversion were significant risk factors for a reduction >25% in tacrolimus blood levels after conversion. No significant change was detected between mean glomerular filtration rate at conversion (57 mL/min) and at 3, 6, and 9 months postconversion.

CONCLUSIONS

Once-daily tacrolimus at similar doses to the twice-daily formulation is an efficient and safe treatment option. Conversion made on 1 mg:1.1 mg basis seems advantageous at least in some patients.

Effect of Different Sensitization Events on HLA Alloimmunization in Kidney Transplantation Candidates

BACKGROUND

HLA alloimmunization is caused by sensitization events (SEs), such as transfusion, pregnancy, or previous organ transplantation, and the effects of particular SEs have not been thoroughly studied. Our aim was to evaluate how each SE affected HLA alloimmunization by considering Luminex assays.

METHODS

Sera from 722 kidney transplantation candidates were screened per protocol by means of Luminex assays to determine the presence of anti-HLA class I/II antibodies; positive sera underwent single-antigen assay to determine the presence of specific antibodies against HLA A, B, C, DR, DQ, DP loci (positivity if median fluorescence intensity values were >1,000). The effect of each SE was analyzed considering only patients exposed to 1 kind of sensitization.

RESULTS

In the 453 candidates with ≥1 SE, anti-HLA class I positivity rates were significantly higher in patients with previous transfusion (18.9%; P = .014), pregnancy (38.3%; P < .001) or transplant (75%; P < .001) compared with those with no SE (similar results for class II). The strength (median fluorescence intensity) of specific antibodies was significantly higher in patients with previous transplantation than in those with previous transfusion for HLA-A (8,017 vs 2,302; P = .02), HLA-B (7,765 vs 2,901; P = .018), and HLA-DR (9,835 vs 2,060; P = .003). Other anti-HLA antibody strengths were similar between patients with previous pregnancy or transplantation.

CONCLUSIONS

Presence of any SE analyzed was associated with a higher prevalence of anti-HLA antibodies for class I ± II compared with nonsensitized patients. Transplantation had the strongest immunization effect on both classes, followed by pregnancy and then transfusion.

Allograft nephrectomy: a single-institution, 10-year experience

INTRODUCTION

Allograft nephrectomy (AN) is associated with a high number of surgical complications. Some authors advocate that early nephrectomy (<1 year) is associated with fewer complications. Intracapsular (ICAN) and extracapsular AN (ECAN) might have a different impact on allosensitization and surgical outcomes. Our goal was to compare surgical outcomes between early and late AN in our institution and to compare ICAN and ECAN in terms of surgical outcomes and panel reactive antibodies (PRA) variation.

MATERIALS AND METHODS

Between January 2000 and October 2012, we performed 104 AN at our institution (32 early and 72 late). Comparisons between early and late AN, and, within the latter, between the 2 different techniques were sought. Statistical analysis was performed for sample description, group comparison and %PRA variation.

RESULTS

Among the 104 patients with a mean age of 47.9 ± 14.2 years, 54 were men. Age, gender, body mass index, and number of previous transplants were similar between early and late AN and between ICAN and ECAN patients. Late AN was associated with less blood loss (293.4 ± 229.0 vs 414.3 ± 349.5 mL; P = .03), shorter hospital stay (12.8 ± 14.5 vs 26.8 ± 26.5; P < .05), and fewer complications (22.2% vs 59.3%; P < .05). The chance of being relisted for transplantation was similar (50.0% in early vs 59.7% in late AN; P = .7). When comparing ICAN and ECAN, there was no difference in surgical outcomes. The %PRA variation between the 2 techniques was comparable (-1.2 ± 10.6 ICAN vs -0.5 ± 15.9 ECAN; P = .8), as was the chance of being relisted for transplantation (60.5% ICAN vs 58.6% ECAN; P = .8).

CONCLUSIONS

Early AN was associated with a greater number of surgical complications. Nevertheless, the number of AN patients returning to the active waiting list was similar between early and late AN groups. ICAN and ECAN had similar surgical and postoperative outcomes, although a bias may be present because some conversions from ECAN to ICAN occurred owing to technical issues. As in other studies, ICAN did not seem to affect allosensitization or jeopardize the chance of being relisted for transplant when compared with ECAN.

The lanthipeptides of Bacillus methylotrophicus and their association with genomic islands

Bacillus methylotrophicus strains are known for their potential as plant-growth promoters and as microbial pesticides that effectively control plant diseases caused by bacteria and fungi. Over the past few years, a wide diversity of their secondary metabolites has been extensively characterized. Among these are the RiPPs lanthipeptides, which are an important and growing group of notable compounds. The increasing interest in B. methylotrophicus species, accompanied by the development of high throughput sequencing techniques, has resulted in a substantial number of full genomes being available. Here, an in silico analysis was performed on these genomes in order to survey the presence of lanthipeptide biosynthetic clusters. It was found that the pan genome of B. methylotrophicus only encoded the biosynthesis of mersacidin and amylolysin, which are lanthipeptides with antibacterial activity. However, the amylolysin gene cluster identified was comprised of more genetic elements than those previously described, and it had certain features of two-peptide lantibiotics. Additionally, it was also established that the association of lanthipeptides with genomic islands (GIs) was not confined to mersacidin. This was also found for the amylolysin cluster as well as other class I and class II lanthipeptides, supporting the idea that their production is probably related to functional adaptation.

Trypanosoma cruzi mitochondrial tryparedoxin peroxidase is located throughout the cell and its pull down provides one step towards the understanding of its mechanism of action

Trypanosoma cruzi depends on the effectiveness of redox metabolism to survive and ensure infection in the host. Homeostasis of redox metabolism in T. cruzi is achieved by the actions of several proteins that differ in many aspects from host proteins. Although extensive research has been performed examining hydroperoxide cytosolic antioxidant defense centered on trypanothione, the mechanisms of mitochondrial antioxidant defense are not yet known. The aim of this study was to elucidate the partners of TcMPx antioxidant pathway and to determine the influence of the cellular context (physiological versus oxidative stress). Through co-precipitation coupled with a mass spectrometry approach, a variety of proteins were detected under physiological and oxidative stress conditions. Interestingly, functional category analysis of the proteins identified under physiological conditions showed that they were involved in the stress response, oxidoreduction, thiol transfer, and metabolic processes; this profile is distinct under oxidative stress conditions likely due to structural alterations. Our findings help to elucidate the reactions involving TcMPx and most importantly also reveal that this protein is present throughout the cell and that its interaction partners change following oxidative stress exposure. The involvement and significance of the proteins found to interact with TcMPx and other possible functions for this protein are discussed widening our knowledge regarding T. cruzi mitochondrial antioxidant defenses.

Living versus cadaveric-donor renal transplant recipients: a comparison on sexual function

Erectile dysfunction is experienced by 50% of men with end-stage renal disease (ESRD) and uremia. The origin of this dysfunction is multifactorial. The aim of this study was to compare living donor versus cadaveric donor transplant recipients regarding male sexual function. Seventy-seven sexually active male kidney transplant recipients (44 from living donors; 33 from cadaveric donors) were randomly selected from our single-center prospective database of 2016 renal transplants. Epidemiological and clinical data were collected between June 2010 and June 2011. Male sexual function was evaluated with the International Index of Erectile Function questionnaire (IIEF-15). We assessed the prevalence of male sexual dysfunction according to established cutoff points for each of the IIEF-15 domains. Mann-Whitney and Pearson's chi- square statistical tests were used to compare continuous and categorical variables, respectively. The median age at the time of completion of the questionnaires was 43 and 51 years (P = .003) with median times from transplantation was of 36 and 42 months for living donor and cadaveric donor recipients, respectively (P = .31). Median durations of ESRD before surgery were 17.5 and 57 months for living donor and cadaveric donor recipients, respectively (P < .001). Living donor and cadaveric donor recipients had median creatinine clearance values of 55 and 57 mL/min, respectively (P = .44). Median time after renal transplantation for first sexual intercourse was 1 and 2 months for living donor and cadaveric donor recipients, respectively (P = .35). Median body mass indices for living donor and cadaveric donor recipients were 24.8 and 24, respectively (P = .31). Regarding sexual function domains, there were significant differences only for intercourse satisfaction. In our cohort, living donor recipients tended to be younger, have shorter time of ESRD, and less incidence of hypertension or diabetes mellitus but with greater tobacco use. In conclusion, living donor transplantation exerted a favorable impact on sexual function.