O-063 Impact of group embryo culture vs individual embryo culture strategies on blastocyst rate and quality

Study question

Does group embryo culture improve blastocyst formation compared to individual culture?

Summary answer

Individual culture provides an increased blastocyst formation rate.

What is known already

Embryo culture is one of the most important steps of an IVF treatment. Several studies pointed out that group embryo culture could help embryos with lower potential, through paracrine signaling, to achieve development and improve blastocyst formation rate. On the other hand, this issue continues to be controversial and other studies did not find differences in embryo development when using either method.

Study design, size, duration

A prospective randomized study was performed between January 2020 and December 2021. The data were obtained from 830 embryos that came from 103 egg donation treatments. We defined two groups: individual vs group culture. The number of embryos analyzed in the study was calculated to test a difference of 10% in the rate of blastocyst formation between the two groups.

Participants/materials, setting, methods

A total of 103 ICSI-egg donation cycles with normozoospermic males (fresh samples) were included. After fertilization assessment, zygotes were randomized into two groups; Group 1: individual culture (399 embryos), and Group 2: culture of 2-5 embryos per drop (431 embryos). The embryos were cultured in 35 µl drops of Global Total medium until day 5 when they were classified morphologically according to Gardner criteria (1998). The statistical analysis was performed using SPSS (version 20.0).

Main results and the role of chance

The rate of high-quality embryos on day 3 were similar in Group 1 compared to Group 2 (79.2% vs 81.4%, p = 0.432). However, we observed an increase in the blastocyst formation rate on day 5 (62.9% vs 56.1%, p = 0.048) and a trend for higher embryo quality (A/B blastocysts) (55.9% vs 52%, p = 0.266) in Group 1; compared to Group 2, respectively.

Our data suggest that individual culture increases blastocyst formation rate and may benefit embryo quality on day 5. Our results challenge previous reports suggesting that culture in groups can improve embryo development. As hypothesis, we argue that some of the components that the embryos release to the culture environment during their division may affect the quality of the cohort potentially compromising further development up to the blastocyst stage.

Limitations, reasons for caution

The study is focused on laboratory outcomes until the blastocyst stage. Clinical outcomes were not analyzed.

Wider implications of the findings

Finding the most appropriate embryo culture conditions is essential to improve ART results. Time-lapse systems should be adapted to the use of both individual and group culture dishes. Larger randomized studies are needed in order to reach robust conclusions on the subject.

Trial registration number

NA

P–162 Laser-assisted collapse of blastocysts prior to vitrification improves clinical outcomes

Study question

What is the effect of artificial laser-assisted collapse before vitrification on pregnancy and implantation rates after transfer of vitrified-warmed blastocysts?

Summary answer

The artificial shrinkage by laser-induced collapse before vitrification significantly increased the implantation and clinical pregnancy rates after single thawed embryo transfer.

What is known already

Freeze all, cycle segmentation and, in general, single embryo transfer (SET) strategies (for example trophectoderm biopsy-based aneuploidy testing) have targeted blastocysts vitrification as the best option for reproductive practice worldwide. Artificial shrinkage seems to be a pre-vitrification parameter associated with an increased embryo survival after warming and implantation rate. However, the available medical evidence shows controversial results with only a limited number of prospective studies assessing the subject.

Study design, size, duration

This prospective cohort study evaluated 394 women who underwent a frozen blastocyst transfer at Instituto Bernabeu between July and December 2020. All patients were prepared with substitutive cycle and received single blastocyst embryo transfers.

Participants/materials, setting, methods

Before embryo vitrification on day 5 of development, some expanded and/or early hatching blastocysts (A/B ASEBIR categories) were artificial laser-assisted collapsed. (n = 83, study group). 311 embryos of the same quality and day of development were not collapsed (control group). We compared the embryo survival rate, clinical, implantation and miscarriage rates between groups. The statistical analysis was performed using SPSS (version 20.0).

Main results and the role of chance

The two groups were comparable in terms of maternal age (39.79 ± 3.83, control group; 40.21 ± 4.45, study group; p = 0.341). Embryo survival rate resulted in 100% in both groups.

Regarding clinical outcomes, collapsed blastocysts significantly increased the positive pregnancy test and the clinical pregnancy and implantation rate compared to the control group, respectively (positive test: 69,9% vs 43,4%, p = 0.000018, odds ratio (OR)= 3.02 [95% CI 1.80–5.08]; clinical pregnancy and implantation: 56,6% vs 35,4%, p = 0.000041, OR = 2.39 [95% CI 1.46–3.90]). The miscarriage rate was not affected by the blastocyst collapse effect (23,6% in the control group vs 27,6% in the study group, p = 0.593, OR = 1.23 [95% CI 0.57–2.68]).

Limitations, reasons for caution

This is a non-randomized controlled study. Additional RCTs are warranted to corroborate our findings.

Wider implications of the findings: Considering the large number of blastocyst vitrification cycles that are carried out worldwide, artificial laser-assisted collapse before vitrification has the potential to increase the clinical results in benefit of many patients.

Trial registration number

Not applicable

P–781 Birthweight is not affected by freezing process. Results from a quasi-experimental study using the Oocyte Donation Model

Study question

Is the freezing process responsible to increase the birthweight or the incidence of Large for Gestational Age (LGA) in Frozen Embryo Transfers (FET)?

Summary answer

Neither the birthweight nor the LGA incidence were different in embryos that underwent the freezing-thawing process.

What is known already

Freezing-thawing constitutes one of the processes with a potential impact on the health of the newborn. Data coming from register-based studies and metaanalisis have found an increase in birthweight with a higher incidence of LGA in newborns coming from FET. This is a matter of concern since epigenetic alterations have been suggested to explain this finding casting doubts on future health during childhood and adulthood. Clarifying the safety of cryotechniques should be a priority taken into account that at present frozen embryo transfers outnumber fresh embryo transfers in IVF clinics.

Study design, size, duration

This retrospective cohort study evaluated 670 women oocyte recipients who underwent fresh (367 cycles) or frozen embryo transfer (303 cycles) at Instituto Bernabeu between July 2017 and March 2019. All recipients were prepared with substitutive cycle and received single blastocyst embryo transfers on day five. All of them at the same culture medium, resulting in a singleton live birth.

Participants/materials, setting, methods

1637 patients were assessed for eligibility but 967 were excluded. The sample size has been calculated accepting an alpha risk of 5% and a beta risk of 20%. A sample size of 266 patients (133 per group) is required to detect a minimum mean difference of 275 grams with a standard deviation of 800 grams. Pearsońs Chi-square test (univariate) and binary logistic regression (multivariate for confounding factors) were used to analyze association between variables.

Main results and the role of chance

Maternal age (42.21 ± 4.45; 42.79 ± 3.83 p = 0.519), BMI (23.34 ± 3.69; 24.99 ± 15.52; p = 0.060), maternal parity (Nulliparous 81.5%; 85.5%; Multiparous 18.5%; 14.5% p = 0.177), gestational diabetes (4.9%; 4.3% p = 0.854), preeclampsia (2.7%; 5.6% p = 0.074), hypertensive disorders (3.3%; 2.3% p = 0.494), maternal smoking (10.8%; 13.0% p = 0.475), gestational age (38.96 ± 1.97; 38.77 ± 2.15; p = 0.207) and liveborn gender (Female 44.5%; 48.8%; Male 55.5%; 51.2%p=0.276) do not present statistically significant differences between fresh or frozen groups, respectively.

However endometrial thickness was statistically signiticantly different in both groups (8.83mm ± 1.73 fresh; 8.57mm ± 1.59 frozen p = 0.035)

The mean birthweight did not present statistically significant differences (3239.21 ± 550.43 fresh; 3224.56 ± 570.83 frozen p = 0.211). There were also no differences regarding macrosomy (7.1% fresh; 6.3% frozen p = 0.317), LGA (6.0% fresh; 6.7% frozen p = 0.866), pre-term birth (10.9% fresh; 9.0% frozen p = 0.988), very pre-term birth (0.8% fresh; 1.3% frozen p = 0.999), and extremely pre-term birth (0% fresh; 1.0% frozen p = 0.998).

There were statistically significant differences regarding underweight (10.0% fresh; 7.0% frozen p = 0.020), but there were no differences in very low weight (0.6 fresh; 1.1% frozen p = 0.972) and SGA (1.9% fresh; 0.7% frozen p = 0.432).

Limitations, reasons for caution

Despite a quasi-experimental design, the synchronization in fresh embryo transfer drove to a longer preparation with a thicker endometrium. It’s not possible to rule-out the influence in the results of this parameter.

Wider implications of the findings: As a hypothesis, the increase in birthweight and/or an abnormal placentation in FET could be explained by the endometrial preparation more than the freezing process. Studies must be planned in the future to explore the possibility of changes in the birthweight between embryos transferred in natural vs artificial endometrial preparations.

Trial registration number

Not applicable

American Heart Association (AHA) Scientific Sessions 2020 (November 13-17, 2020 - Virtual Meeting)

Participants from industry and academia attended the American Heart Association Scientific Sessions 2020 (AHA 2020) Annual Meeting held over November 13-17, 2020. AHA 2020 was originally scheduled to be held in Dallas, Texas, but due to public health concerns surrounding the SARS-CoV-2 (COVID-19) crisis, it was instead presented as a virtual summit. The virtual online program included oral, poster and poster discussion presentations, as well as track-based clinical science symposia throughout the conference.

Characterization of the European Sea Bass (Dicentrarchus labrax) Gonadal Transcriptome During Sexual Development

The European sea bass is one of the most important cultured fish in Europe and has a marked sexual growth dimorphism in favor of females. It is a gonochoristic species with polygenic sex determination, where a combination between still undifferentiated genetic factors and environmental temperature determines sex ratios. The molecular mechanisms responsible for gonadal sex differentiation are still unknown. Here, we sampled fish during the gonadal developmental period (110 to 350 days post fertilization, dpf), and performed a comprehensive transcriptomic study by using a species-specific microarray. This analysis uncovered sex-specific gonadal transcriptomic profiles at each stage of development, identifying larger number of differentially expressed genes in ovaries when compared to testis. The expression patterns of 54 reproduction-related genes were analyzed. We found that hsd17β10 is a reliable marker of early ovarian differentiation. Further, three genes, pdgfb, snx1, and nfy, not previously related to fish sex differentiation, were tightly associated with testis development in the sea bass. Regarding signaling pathways, lysine degradation, bladder cancer, and NOD-like receptor signaling were enriched for ovarian development while eight pathways including basal transcription factors and steroid biosynthesis were enriched for testis development. Analysis of the transcription factor abundance showed an earlier increase in females than in males. Our results show that, although many players in the sex differentiation pathways are conserved among species, there are peculiarities in gene expression worth exploring. The genes identified in this study illustrate the diversity of players involved in fish sex differentiation and can become potential biomarkers for the management of sex ratios in the European sea bass and perhaps other cultured species.

Abstract P6-18-17: Ribociclib + letrozole in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (aBC) with no prior endocrine therapy (ET) for ABC: CompLEEment-1 trial, preliminary results from Spanish population

Background: The phase III Monaleesa-2, Monaleesa-3 and Monaleesa-7 trials have shown significantly improved PFS for the combination ribociclib + ET vs ET + placebo in pre-, peri-, and postmenopausal women with HR+/HER2–, first and second line aBC. The Compleement-1 trial is a phase IIIb, single-arm, open-label, international study to assess the safety and efficacy of ribociclib + letrozole in men and women who have not received prior ET for HR+, HER2– ABC [J Clin Oncol 36, 2018 (suppl; abstr 1056)].

Methods: 526 patients with HR+, HER2– ABC, ≤1 line of prior CT, and no prior ET for aBC were enrolled in the Compleement-1trial in Spain from April 2017 to January 2018. Patients received ribociclib (600 mg/day, 3 weeks on/1 week off) + letrozole (2.5 mg/day); men and premenopausal women received concomitant goserelin (3.6 mg subcutaneous implant every 28 days). The primary objective was safety and tolerability. Here we report on a sub-analysis from the Spanish population of Compleement-1 trial including baseline characteristics and early safety results for the first patients enrolled who completed at least 56 days of follow-up or discontinued before the cut-off date (3rd Oct 2017).

Results: One hundred fifty four patients constituted the analytical cohort for this sub-analysis. Demographics and baseline characteristics: median age was 52 years (range 24-82); 1% of patients were male, 31.8% female pre-menopausal and 67.5% female post-menopausal; 44.2% vs 38.3% of patients had visceral disease vs bone only disease; 49.9% patients had ≥2 metastatic sites; and 34.4% of patients presented as de novo stage IV. The median exposure for study treatment was 1.8 months (range 0.8-1.8). The grade 3/4 events reported >1% included neutropenia (50%), increased GGT levels (3.2%), leukopenia (1.3%), and increased ALT (1.3%). QTcF prolongation >480ms based on ECG data was reported in 1.2% patients. Median dose intensity for ribociclib was 600mg/day (range 476.5-600); 11% of patients required one dose reduction (8.4% due to AEs), 59.7% had at least one dose interruption (57.1% due to AEs) and 9.7% were permanently discontinued (4.5% due to AEs).

Conclusions: Preliminary safety results from this Compleement-1 sub-analysis including Spanish population are consistent with previous data presented from Monaleesa-2, Monaleesa-3, Monaleesa-7 and Compleement-1. These data support the predictable and manageable safety profile of ribociclib in combination with letrozole. Clinical trial information: NCT02941926

Citation Format: Salvador J, Ciruelos EM, Prat A, Jiménez-Rodríguez B, de la Cruz L, Martínez N, Villanueva Vázquez R, de Toro R, Antón A, Moreno F, Alvarez I, Gavila J, Quiroga V, Vicente E, de la Haba J, González-Santiago S, Díaz N, Barnadas A, Cantos Sánchez de Ibargüen B, Delgado JI, Bellet M, Gimeno A, Sanz S, Martin M. Ribociclib + letrozole in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (aBC) with no prior endocrine therapy (ET) for ABC: CompLEEment-1 trial, preliminary results from Spanish population [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-18-17.

Real-world data on the efficacy and safety of weekly oral vinorelbine in breast cancer patients previously treated with anthracycline or taxane-based regimens

PURPOSE

To evaluate the efficacy and safety of oral weekly vinorelbine 60 mg/m² for metastatic breast cancer (MBC) in patients previously treated with anthracyclines or taxanes in routine clinical practice.

MATERIALS AND METHODS

Fifty-five patients were enrolled in a prospective multicentre study conducted in Spain. Women ≥ 18 years of age with locally advanced breast cancer who were not candidates for surgical treatment with a radical intention or patients with stage IV disease, and who had received a prior taxane or anthracycline regimen were eligible for participation.

RESULTS

Median age was 67 years. Median progression-free survival was 3.7 months (95% CI 2.5-4.9), median overall survival 10 months (95% CI 6.6-13.5), and overall response rate and clinical benefit rate were 29.1% and 49.1%, respectively. Main grade 3 and 4 toxicities were neutropenia 9.1%, febrile neutropenia 3.6% and constipation 3.6%. In total, 86% of the patients received complete treatment without delays or dose reduction. Moreover, HER2-positive patients who received oral vinorelbine concomitantly with trastuzumab showed better response (complete response: HER2-positive 14.3% vs. HER2-negative 0%; partial response: HER2-positive 42.9% vs. HER2-negative 25.6%; p = 0.008), better disease control rate (HER2-positive 100% vs. HER2-negative 46.2%; p = 0.011), and better values for the remaining analysed variables than HER2-negative patients.

CONCLUSION

Our study provides real-world data on the use of oral weekly vinorelbine, which proves an effective and well-tolerated regimen for MBC patients previously treated with taxanes or anthracyclines. Patients with HER2-positive disease could also benefit from this treatment in combination with trastuzumab.

European and Americas Committees for Treatment and Research in Multiple Sclerosis (ECTRIMS/ACTRIMS) - 7th Joint Triennial Congress (October 25-28, 2017 - Paris, France)

The 7th Triennial Joint conference of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) and Americas Committee for Treatment and Research in Multiple Sclerosis (ACTRIMS) was held in Paris, France. The meeting brought together attendees from a wide range of disciplines involved in multiple sclerosis (MS) research to explore an extensive program of teaching courses, plenary lectures, oral and poster sessions from approximately 2,000 abstracts submitted, and hot topic and young investigator presentations. These presentations covered topics including diagnostics, therapeutics and biomarkers, as well as a special section for MS nurses. Industry-sponsored symposia were also held. The report from this conference covers the latest developments in MS treatments.

Fabrication of Superhydrophobic Polyethylene Parts by Rotomolding

In this study, the feasibility of obtaining superhydrophobic polyethylene parts by rotational molding has been confirmed. The superhydrophobicity is obtained through the surface modification of the thermoplastic by using a microrough aluminium mold. The treatment used to create the microroughness of the mold was an electrochemical process followed by heating at 180 °C. Once the superhydrophobic aluminium mold has been prepared, several rotomolding cycles were carried out. The mold was then used for obtaining rotomolded test cube parts using a conventional polyethylene grade. The behavior of the parts under a water jet show a superhydrophobic behavior of the surface, fact confirmed by the measurement of contact angles above 145°.

Three axis vector magnet set-up for cryogenic scanning probe microscopy

We describe a three axis vector magnet system for cryogenic scanning probe microscopy measurements. We discuss the magnet support system and the power supply, consisting of a compact three way 100 A current source. We obtain tilted magnetic fields in all directions with maximum value of 5T along z-axis and of 1.2T for XY-plane magnetic fields. We describe a scanning tunneling microscopy-spectroscopy (STM-STS) set-up, operating in a dilution refrigerator, which includes a new high voltage ultralow noise piezodrive electronics and discuss the noise level due to vibrations. STM images and STS maps show atomic resolution and the tilted vortex lattice at 150 mK in the superconductor β-Bi2Pd. We observe a strongly elongated hexagonal lattice, which corresponds to the projection of the tilted hexagonal vortex lattice on the surface. We also discuss Magnetic Force Microscopy images in a variable temperature insert.

Caveolin-1 in cell migration and metastasis

Caveolin-1 is a member of the caveolin family that has been ascribed a dual role in cancer. In early stages of disease the protein functions predominantly as a tumor suppressor, whereas at later stages, caveolin-1 expression is associated with tumor progression and metastasis. Here, some mechanisms associated with caveolin-1-dependent tumor suppression will be briefly discussed before focusing on the role of this protein and particularly phosphorylation of tyrosine-14 in promoting cell migration, invasion and metastasis. Models are provided summarizing possible explanations for these dramatic changes in function, as well as mechanisms by which this may be achieved.

Caveolin-1 in cell migration and metastasis

Caveolin-1 is a member of the caveolin family that has been ascribed a dual role in cancer. In early stages of disease the protein functions predominantly as a tumor suppressor, whereas at later stages, caveolin-1 expression is associated with tumor progression and metastasis. Here, some mechanisms associated with caveolin-1-dependent tumor suppression will be briefly discussed before focusing on the role of this protein and particularly phosphorylation of tyrosine-14 in promoting cell migration, invasion and metastasis. Models are provided summarizing possible explanations for these dramatic changes in function, as well as mechanisms by which this may be achieved.

[Review of initiatives carried out in Spain to implement teaching of basic cardiopulmonary reanimation in schools]

Cardiorespiratory arrest (CRA) is a situation of maximum medical emergency which can be potentially reversed if basic cardiopulmonary resuscitation manoeuvres (CPR) are provided by the first bystander. Nonetheless, this is done in less than 25 % of the cardiorespiratory arrests (CRA) witnessed by bystanders. Thus, it is urgent to increase the knowledge of such basic CPR manoeuvres among the public in general. One strategy consists in the teaching of basic CPR techniques in schools following the recommendations made by specialized institutions. This study analyzes the initiatives carried out in Spain, including the authors' own experience acquired during the development of PROCES, a program aimed a students from 15 to 16 years of age and carried out during the last 10 years in Barcelona.

Optimization of municipal sludge and grease co-digestion using disintegration technologies

Many drivers tend to foster the development of renewable energy production in wastewater treatment plants as many expectations rely upon energy recovery from sewage sludge, for example through biogas use. This paper is focused on the assessment of grease waste (GW) as an adequate substrate for co-digestion with municipal sludge, as it has a methane potential of 479-710 LCH(4)/kg VS, as well as the evaluation of disintegration technologies as a method to optimize the co-digestion process. With this objective three different pre-treatments have been selected for evaluation: thermal hydrolysis, ultrasound and enzymatic treatment. Results have shown that co-digestion processes without pre-treatment had a maximum increment of 128% of the volumetric methane productivity when GW addition was 23% inlet (at 20 days of HRT and with an OLR of 3.0 kg COD/m(3)d), compared with conventional digestion of sewage sludge alone. Concerning the application of the selected disintegration technologies, all pre-treatments showed improvements in terms of methane yield (51.8, 89.5 and 57.6% more for thermal hydrolysis, ultrasound and enzymatic treatment, respectively, compared with non-pretreated wastes), thermal hydrolysis of GW and secondary sludge being the best configuration as it improved the solubilization of the organic matter and the hydrodynamic characteristics of digestates.

The Caenorhabditis elegans genome: a multifractal analysis

The Caenorhabditis elegans genome has several regular and irregular characteristics in its nucleotide composition; these are observed within and between chromosomes. To study these particularities, we carried out a multifractal analysis, which requires a large number of exponents to characterize scaling properties. We looked for a relationship between the genetic information content of the chromosomes and multifractal parameters and found less multifractality compared to the human genome. Differences in multifractality among chromosomes and in regions of chromosomes, and two group averages of chromosome regions were observed. All these differences were mainly dependent on differences in the contents of repetitive DNA. Based on these properties, we propose a nonlinear model for the structure of the C. elegans genome, with some biological implications. These results suggest that examining differences in multifractality is a viable approach for measuring local variations of genomic information contents along chromosomes. This approach could be extended to other genomes in order to characterize structural and functional regions of chromosomes.

[Relation between leptin serun with weight and body fat distribution in postmenopausal women]

Leptin is a peptidic hormone secreted by the fat tissue and plays an important role in body weight regulation. After menopause, weight gain increases as well as android-like obesity. Previous studies suggest a relationship between leptin level, body mass index (BMI) and fat distribution.

OBJECTIVE

To establish the relationships between serum leptin, BMI, waist circumference (WC), and waist/hip ratio (WHR).

METHODOLOGY

48 women under the age of 60 years and with amenorrhea for longer than one year were assessed. Leptin and estradiol (ELISA) levels were determined; normal values: 3.63-11.09 ng/mL and 0-65 pg/Ml. BMI (WHO), WC > 88 cm, and WHR > 0.80 were considered as indicators of cardiometabolic risk.

RESULTS

Mean age for the group was 54 +/- 3.9 years; leptin: 8.4 +/- 3.7 ng/mL, and estradiol: 17.6 +/- 10.0 pg/mL; BMI: 27.0 +/- 4.9 kg/m(2); WC: 86.2 +/- 8.6 cm; and WHR: 0.84 +/- 0.06. Twenty percent of the women had hyperleptinemia, 58.4% malnourishment due to excessive intake, 35% presented WC cardiovascular risk. The highest leptin value was found in obese women. There was no association between serum leptin levels and anthropometrical variables. There was a significantly positive correlation between weight, height, BMI, WC, hip circumference, and estradiol.

CONCLUSIONS

Postmenopausal women presented a high prevalence of overweight/obesity, android-like body fat distribution and normal serum leptin levels. The group assessed is considered to be at risk for cardiometabolic diseases according to anthropometrical indicators.

High-sensitivity C-reactive protein and liver enzymes in individuals with Metabolic Syndrome in Talca, Chile

Metabolic syndrome (MS) is a core set of disorders, including abdominal obesity, dyslipidemia, hypertension and hypertriglyceridemia that together predict the development of diabetes type 2 and cardiovascular disease. This study investigated the relationship between liver enzyme levels and high-sensitivity C-reactive protein (hs-CRP) in subjects with and without MS. Alanine-aminotransferase (ALAT), aspartate-aminotransferase (ASAT), γ-glutamyl transferase (GGT) and hs-CRP were measured in 510 subjects, aged 40 to 65 years old. Patients were selected from 1007 subjects from the Research Program for Cardiovascular Disease Risk Factors in Talca, Chile. Results showed that women with MS presented higher liver enzyme levels than those who did not have MS. This was not observed in male patients for the enzymes ALAT and ASAT. However, GGT and hs-PCR levels were higher in male and female patients with MS than in those without MS. In conclusion, it is important to search for the presence of MS when diagnosing fatty liver. Moreover, the presence of liver disease in patients with MS should be further investigated.

Evaluation of clinical use of darbepoetin alfa in patients with chemotherapy-induced anemia

e20585

Background: Chemotherapy-induced anemia (CIA) is a frequent complication of patients (pts) with cancer and could be treated with erythropoiesis-stimulating agents such darbepoetin alfa (DA). The aim of this study was to investigate the patterns of use and effect of DA to treat CIA in clinical practice conditions. Methods: This was an observational, retrospective, multicenter study performed in 58 Spanish centres. Eligible pts were ≥18 yrs, diagnosed with non-myeloid malignancies and treated with chemotherapy (CT) and DA from October 2005 to October 2006. Data on demographic and clinical characteristics, CT and radiotherapy (RT), DA administration, red blood cell (RBC) transfusions, and haemoglobin (Hb) levels were collected from DA treatment initiation up to a maximum of 16 weeks or until treatment discontinuation. Results: A total of 685 pts were included in the study. Median age was 64.66 years (range 18.54–88.95), 50.7% were women, 74.11% had ECOG status 0–1 and 71.38% had stage III/IV cancer. Solid tumours represented 72.55% of the cases. The CT regimen included platinum derivates in 33.58% of the pts. At DA initiation, mean (SD) Hb was 10.00 g/dL (1.05) Administration of DA every three weeks occurred in 54.01% of the pts. Mean (SD) DA administration was 9.20 weeks (5.31). Hematopoietic response (defined as Hb ≥ 12 g/dL or Hb rise from baseline >2 g/dL in the absence of RBC transfusions during the previous 28 days) occurred in 63.24% (95% CI 59.49–66.83) of pts. A total of 88 pts (12.85%) required RBC transfusions from week 5 to end of treatment. Mean Hb (SD) at the end of treatment with DA was 11.36 g/dL (1.73). Adverse event (AE) potentially related to DA were reported in 20 pts (2.92%) and considered severe in 6 cases (0.88%). Conclusions: The findings of this study indicate that the use of DA for the treatment of CIA in real-life, daily oncology and haematology practice, is well-tolerated and effective for increasing haemoglobin to reduce the need of RBC transfusions.

[Table: see text]

Evaluation of the pathogenicity and transmissibility of a chilean isolate of porcine reproductive and respiratory syndrome virus

The objective of this study was to determine clinical features, shedding and transmission of a Chilean Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) strain upon experimental inoculation of 4-week-old pigs. Six groups of five animals each were used. The G1 (donor) group was inoculated with PRRSV, maintained in an isolation unit for 35 days, and sampled daily to determine shedding in mucosal secretions and faeces, viraemia and seroconversion. An uninfected control group (G6) was equally maintained and sampled under strict isolation. Four other groups (G2 to G5) were exposed to PRRSV via direct contact with G1 for 5-day periods in a staggered manner, throughout the 35-day period, and were later placed in an independent isolation unit to monitor infection status for 7 days. All the animals in G1 and G6 were killed at 35 days post-inoculation (dpi) and the contact groups at 12 days post-contact (dpc). Samples were obtained from diverse organs for histopathological, immunohistochemical (IHC) and virological analysis. No clinical symptoms were evident in any group, except for a transient fever observed in G1. Histopathologically, all the animals of G1 had interstitial pneumonia, although scarce PRRSV-positive cells were detected in the lung using IHC. PRRSV-positive cells (IHC) were detected in the lymphoid tissue of all animals in infected groups, but especially in G3 and G4. Viraemia was detected in G1 (3-35 dpi) and in the all contact groups (5-12 dpc). Likewise, ranging from 3 to 19 dpi, PRRSV was detected in at least one animal from the tonsils and lungs in all infected groups, in nasal and ocular secretions, saliva or faeces. These results indicate that the donor group excreted infectious PRRSV and was able to transmit the infection to susceptible pigs. The critical shedding period was 7-19 dpi, during which, most likely, transmission took place.

Phase II comparative study of capecitabine combined with oxaliplatin (XELOX) and CPT-11 (XELIRI) for advanced colorectal cancer patients (p) previously treated with 5-FU-based chemotherapy

14544

Background: Based on the results obtained with Capecitabine (XEL), Oxaliplatin (OX), and CPT-11 (IRI), we proposed this exploratory study to asses the efficacy of XELIRI and XELOX, for advanced colorectal cancer, after a first line treatment with 5 FU plus OX (FOLFOX) or IRI (FOLFIRI). Methods: P aged = 18 with histological diagnosis of metastatic colorectal adenocarcinoma, were assigned to XELOX arm (XEL, 1000 mg/m2 BID during 14 d; OX, 130 mg/m2 d1; q3w) or XELIRI arm (XEL 1000 mg/m2 BID during 14 d; IRI 240 mg/m2 d1; q3w), depending on previous treatment (FOLFIRI or FOLFOX, respectively). Although sample size was calculated for 115 p, recruitment was premature closed due to the low inclusion rate related with cetuximab + IRI approval for second line treatment. Results: Forty three p (25 p, XELOX; 18 p, XELIRI) were enrolled: median age 63.2 years; M/F, 40.5%/59.5%; ECOG PS 0–1, 79.1%. All p have been previously treated for metastatic disease and 65.1% had stage IV. Main sites of metastatic disease were liver (71.8%), lymph nodes (7.7%), pelvis (7.7 %) and lung (5.1%). XELOX/XELIRI treatment data: total number of administered cycles was 94/85 and median relative dose intensity 100%(XEL)/99%(OX) and 96%(XEL)/94%(IRI); disease control rate (PR+SD) was 28%/33.3%, median TTP 3.4/4.1 months, median OS 10.3/11.2 months and 1-year survival, 39.1%/44.3%, respectively. Twenty p (46.5%) received further antitumoral treatment. Most frequent G3–4 toxicities per p are detailed in table 1 . Conclusions: Capecitabine based combinations show an excellent toxicity profile and good efficacy results, in terms of disease control and survival rates, for advanced colorectal cancer patients previously treated with 5-FU schedules.

[Table: see text]

No significant financial relationships to disclose.

Twelve-year follow-up study of the impact of nutritional status at the onset of elementary school on later educational situation of Chilean school-age children

OBJECTIVE

To determine the impact of nutritional status in a multicausal approach of socio-economic, socio-cultural, family, intellectual, educational and demographic variables at the onset of elementary school in 1987 on the educational situation of these children in 1998, when they should have graduated from high school.

SETTING

Chile's Metropolitan Region.

DESIGN

Prospective, observational and 12-year follow-up study.

METHODS

A representative sample of 813 elementary first grade school-age children was randomly chosen in 1987. The sample was assessed in two cross-sectional studies. The first cross-sectional study was carried out in at the onset of elementary school in 1987 and the second was carried out in 1998, 12-years later, when they should be graduating from high school. In 1998, 632 adolescent students were located and their educational situation was registered (dropout, delayed, graduated and not located). At the onset of elementary school were determined the nutritional status, socio-economic status (SES), family characteristics, intellectual ability (IA), scholastic achievement (SA) and demographic variables. Statistical analysis included variance tests and Scheffe's test was used for comparison of means. Pearson correlation coefficients and logistic regression were used to establish the most important independent variables at the onset of elementary school in 1987 that affect the educational situation 1998. Data were analysed using the statistical analysis system (SAS).

RESULTS

Logistic regression revealed that SES, IA, SA and head circumference-for-age Z score at the onset of elementary school in 1987 were the independent variables with the greatest explanatory power in the educational situation of school-age children in 1998.

CONCLUSIONS

These parameters at an early school age are good predictors of the educational situation later and these results can be useful for nutrition and educational planning in early childhood.

Radioinmunolocalización de tumores de cabeza y cuello con un nuevo anticuerpo monoclonal contra el receptor del EGF. Resultados preliminares

OBJECTIVE

To show the results of Radioimmunodetection (RID) using Cuban monoclonal antibody (MoA) anti-egf-ior-egf-r3 labeled with 99mTc for the detection of primary tumors and/or metastases of head and neck epithelial malignant tumors.

MATERIAL AND METHODS

Thirteen patients aged from 16-62 years (mean: 54.8 years) with primary tumors and metastases in the regional cervical lymph nodes were retrospectively evaluated. The labelling dose was 1480-2220 MBq (40-60 mCi). Planar images were performed after 10 minutes and together with SPECT images after 18-24 hours following MoA administration. The matrix was 128 x 128. SPECT images were reconstructed using the Butterworth 4/16 filter. A positive result was defined when the lesions were visualized.

RESULTS

RID localized 11 of the known primary tumors in the 13 patients studied. In the two other patients, in whom the primary tumor site was unknown, cervical lymph node metastases were found. The results of 3 of the RID were false negative but in the other 10, RID was able to localize the primary tumor and cervical lymph node metastases. Sensitivity was 77 % and the predictive positive value was 100 %.

CONCLUSIONS

The results of this study show that the Cuban MoA ior-egf-r3 can be employed for RID of primary head and neck tumors and their metastases. The radiation dose is adequate for RID.

Incidence rate of type 1 diabetes in Santiago (Chile) by HLA-DQA1 and DQB1 genotypes

The aim of this study was to estimate annual incidence rate of type 1 diabetes according to the levels of genetic susceptibility provided by HLA-DQA1 and HLA-DQB1 genotypes. Two information sources were used: (1) a population-based incidence study in which 61 incident cases were ascertained during 1 year in Santiago, Chile (incidence rate: 4.11 cases per 100,000 children per year) and (2) a case-control comparison of 57 cases (recruited from the incidence study) and 125 controls. Susceptibility alleles were defined as DQA1*0301 and DQA1*0501 for DQA1 gene and alleles DQB1*0201 and DQB1*0302 for DQB1 gene. In DQA1 gene, the highest point estimate of the incidence rate was calculated for the genotype DQA1*0501/DQA1*0501 (33.04 cases per 100,000 children aged less than 15 years old and per year; 95% CI: 9.22-118.33). In the DQB1 gene, the highest risk was estimated for the genotype DQB1*0201/DQB1*0201 (20.35 cases per 100,000 children aged less than 15 years old and per year; 95% CI: 5.26-78.67). This study shows an application on how a transformation of the logistic equation based on Bayes' theorem can be used to estimate incidence rates from case-control studies and population-based incidence rates.

Molecular dynamics simulations of the mononuclear zinc-beta-lactamase from Bacillus cereus complexed with benzylpenicillin and a quantum chemical study of the reaction mechanism

Herein, we present results from MD simulations of the Michaelis complex formed between the B. cereus zinc-beta-lactamase enzyme and benzylpenicillin. The structural and dynamical effects induced by substrate-binding, the specific role of the conserved residues, and the near attack conformers of the Michaelis complex are discussed. Quantum chemical methods (HF/6-31G* and B3LYP/6-31G*) are also applied to study the hydrolysis reaction of N-methylazetidinone catalyzed by a monozinc system consisting of the side chains of the histidine residues (His86, His88, and His149) complexed with Zn-OH and the side chains of Asp90 and His210. From this model system, we built molecular-mechanics representations of the prereactive complex and transition state configurations docked into the active site. Linear-scaling semiempirical calculations coupled with a continuum solvent model were then performed on these static models. We propose that the experimental rate data for the B. cereus enzyme is compatible with a one-step mechanism for the hydrolysis of beta-lactam substrates in which His210 acts as a proton donor.

Chemotherapy plus interferon-alpha2b versus chemotherapy in the treatment of follicular lymphoma

The best treatment of follicular lymphoma remains to be determined because the long natural history of follicular lymphoma requires mature data for accurate analysis. Although the goal of primary treatment remains durable remission, the sequential application of effective treatments may also result in a prolongation of median survival time. The use of interferon (IFN) with doxorubicin-based chemotherapy has demonstrated an increase of event-free survival but not in overall survival; however, its acute and late cardiac toxicity limits its use. For this reason, we began a controlled clinical trial to assess the efficacy and toxicity of chemotherapy: COPP (cyclophosphamide, vincristine, prednisone, and procarbazine) + IFN alternating every month for six cycles compared to six cycles of chemotherapy. In an intent-to treat analysis, 55 patients were enrolled (median age 61 years). Most cases (91%) with advanced disease were randomly assigned to chemotherapy + IFN (28 cases) or chemotherapy (27 cases). Complete remission was observed in 16 patients: 59% (95% CI, 53-70%) in the chemotherapy arm compared to 20 patients 71% (95% CI, 58-79%) in the chemotherapy + IFN arm; total responses were 74% and 86%, respectively. At a median follow-up of 60 months, event-free survival was 100% for patients treated with chemotherapy + IFN, which was statistically different from patients treated with chemotherapy 70%. At 7 years, median survival has not yet been reached; 72% of patients chemotherapy + IFN remain alive without disease (95% CI, 59-81%), which is not statistically different from 72% (95%CI, 50-73%) in the chemotherapy arm. Non-hematological toxicity was most frequent and severe in the chemotherapy arm; hematological toxicity was similar in both groups. Thus, it appears that chemotherapy + IFN, as described herein, improves event-free survival but the overall survival rates remain unchanged. The use of COPP appears to be better that anthracycline-based chemotherapy because it avoids the presence of acute and late cardiac toxicity.

A theoretical study of the aminolysis reaction of lysine 199 of human serum albumin with benzylpenicillin: consequences for immunochemistry of penicillins

Herein, we present results of a computational study on benzylpenicillin attachment to Lys199 of human serum albumin via an aminolysis reaction. The internal geometry of the reactive part of the system was taken from previous work at the B3LYP/6-31+G* level on the water-assisted aminolysis reaction of a penicillin model compound (Díaz, N.; Suárez, D.; Sordo, T. L. J. Am. Chem. Soc. 2000, 122, 6710--6719). The protein environment around Lys199, the 6-acylamino side chain, and the 2-methyl groups of benzylpenicillin were relaxed by carrying out geometry optimizations with a hybrid QM/MM method (PM3/AMBER). Two different mechanistic routes were explored: a one-step water-assisted process and a carboxylate and water-assisted route in which the beta-lactam carboxylate and the ancillary water molecule mediate the proton transfer from the epsilon-amino group of Lys199 to the beta-lactam leaving N atom. The corresponding energy profiles in the protein combine the B3LYP/6-31+G* and PM3 energies of the reactive subsystem (benzylpenicillin + Lys199 side chain + the ancillary water molecule) and semiempirical PM3 energies of the entire system evaluated with a "divide and conquer" linear-scaling method. It is observed that penicillin haptenation to HSA can proceed through the water-assisted concerted mechanism which is calculated to have a high energy barrier of approximately 38 kcal/mol, in agreement with the experimentally observed slow reaction kinetics.

[Pilot study with the monoclonal antibody IOR-C5 as a potential agent of radioimmunoscintigraphy in colorectal cancer]

IOR C-5 is a G1 immunoglobulin type intact murine monoclonal antibody (MAb) that was developed in the Center of Molecular Immunology in Havana City, Cuba. In immunohistochemical studies, this demonstrated a significant affinity for the epithelial tissues so that it was used in a pilot clinical study to perform a radioimmunoscintigraphy of the colorectal primary tumors and their locoregional recurrences. It was labeled with 99mTc using the Schwarz method, with a > 95% performance. Planar images of the chest, abdomen and pelvis were performed at 10 minutes, 4-6 hours and 18-24 hours post-injection in the anterior and posterior projections and the SPECT was performed 4-6 hours and 18-24 hours post-injection of 1.85 GBq 99mTC. This study has aimed to verify in vivo the capacity of ior-C5 MAb to accumulate in the malignant colorectal lesions. ior-C5 accumulated in 5 out of the 7 patients who were studied and who were suffering from colorectal cancer or in whom there was suspicion of recurrence. There was a negative case of primary tumors, which was an adenocarcinoma in situ in a tubular-papillary adenoma. The second case with a negative radioimmunoscintigraphy was a true negative case.

CONCLUSIONS

It can be concluded that even though the number of patients is quite low, ior-C5 fulfilled the expectations of recognizing the epitope expressed in colorectal tumors in an in vivo human environment.

Evaluation of the catalytic mechanism of AICAR transformylase by pH-dependent kinetics, mutagenesis, and quantum chemical calculations

The catalytic mechanism of 5-aminoimidazole-4-carboxamide ribonucleotide transformylase (AICAR Tfase) is evaluated with pH dependent kinetics, site-directed mutagenesis, and quantum chemical calculations. The chemistry step, represented by the burst rates, was not pH-dependent, which is consistent with our proposed mechanism that the 4-carboxamide of AICAR assists proton shuttling. Quantum chemical calculations on a model system of 5-amino-4-carboxamide imidazole (AICA) and formamide using the B3LYP/6-31G level of theory confirmed that the 4-carboxamide participated in the proton-shuttling mechanism. The result also indicated that the amide-assisted mechanism is concerted such that the proton transfers from the 5-amino group to the formamide are simultaneous with nucleophilic attack by the 5-amino group. Because the process does not lead to a kinetically stable intermediate, the intramolecular proton transfer from the 5-amino group through the 4-carboxamide to the formamide proceeds in the same transition state. Interestingly, the calculations predicted that protonation of the N3 of the imidazole of AICA would reduce the energy barrier significantly. However, the pK(a) of the imidazole of AICAR was determined to be 3.23 +/- 0.01 by NMR titration, and AICAR is likely to bind to the enzyme with its imidazole in the free base form. An alternative pathway was suggested by modeling Lys266 to have a hydrogen-bonding interaction with the N3 of the imidazole of AICAR. Lys266 has been implicated in catalysis based on mutagenesis studies and the recent X-ray structure of AICAR Tfase. The quantum chemical calculations on a model system that contains AICA complexed with CH3NH3+ as a mimic of the Lys residue confirmed that such an interaction lowered the activation energy of the reaction and likewise implicated the 4-carboxamide. To experimentally verify this hypothesis, we prepared the K266R mutant and found that its kcat is reduced by 150-fold from that of the wild type without changes in substrate and cofactor Km values. The kcat-pH profile indicated virtually no pH-dependence in the pH range 6-10.5. The results suggest that the ammonium moiety of Lys or Arg is important in catalysis, most likely acting as a general acid catalyst with a pK(a) value greater than 10.5. The H267A mutant was also prepared since His267 has been found in the active site and implicated in catalysis. The mutant enzyme showed no detectable activity while retaining its binding affinity for substrate, indicating that it plays a critical role in catalysis. We propose that His267 interacts with Lys266 to aid in the precise positioning of the general acid catalyst to the N3 of the imidazole of AICAR.

Molecular dynamics study of the IIA binding site in human serum albumin: influence of the protonation state of Lys195 and Lys199

The IIA binding site of human serum albumin (HSA) preferentially binds hydrophobic organic anions of medium size (e.g., aspirin, benzylpenicillin, warfarin, etc.) and bilirubin. This binding ability is particularly important for the distribution, metabolism, and efficacy of drugs. In addition, HSA can also covalently link to different IIA substrates owing to the presence of a highly reactive residue, Lys199, which is strategically located in the IIA site. Herein, we present results of three restrained molecular dynamics (MD) simulations of the IIA binding site on the HSA protein. From these simulations, we have determined the influence that the ionization state of the key residue, Lys199, and the nearby Lys195 has on the structure and dynamics of the IIA binding site. When Lys199 is neutral the computed average distances for the most significant interresidue contacts are in good agreement with those estimated from the X-ray coordinates. The analysis of the solvent structure and dynamics indicates that the basic form of Lys199 is likely connected to the acid form of Lys195 through a network of H-bonding water molecules with a donor --> acceptor character. The presence of these water bridges can be important for stabilizing the configuration of the IIA binding site and/or promoting a potential Lys195 --> Lys199 proton-transfer process. These results suggest that both lysine residues located in the IIA binding site of HSA, Lys195 and Lys199, could play a combined and comparable chemical role. Our simulations also give insight into the binding of bilirubin to HSA.

[Nutritional status and clinical evolution of hospitalized Chilean infants with infection by respiratory syncytial virus (RSV)]

Respiratory syncycial virus (RSV) is the first cause of acute lower respiratory tract infection in Chilean infants. A significant impact of nutrition on clinical course of these infections has been described. In order to analyze the association between nutritional status (NS) and clinical course of infants hospitalized with acute lower respiratory tract infection due to RSV, 130 infants (mean age 5.8 +/- 4.9 m) without chronic diseases, admitted to hospital with confirmed RSV infection, were studied. Clinical course of disease was assessed (hospitalization days and days with oxygen therapy) according to nutritional status on admission (weight/length (W/L), ratio, arm muscle area, lymphocyte count and albumin), antropometrics changes, and hospital dietary intake. On admission prevalence of malnutrition by W/L (z score) was 1%, 14% overweight and 8% were obese. Median value of hospitalization days was 5 d (2-29 d) and days receiving oxygen was 3 d (0-19 d). Longer admission were observed in fasted patients than in those who were fed everyday (Wilcoxon and Log-rank test, 8 d vs 5 d; P < 0.01). Obese children (Wilcoxon and Log-rank test, 5 d vs. 3d in normal patients; P < 0.05), and patients not fed enterally (Wilcoxon and Log-rank test, 7 d vs. 3 d; P < 0.01) required oxygen for longer time. Fasting and severity of illness (Tal score) were correlated variables (X2 0.001). The multivariate analysis showed an association of Tal score and NS on admission, with days receiving oxygen therapy. We conclude that obesity is a risk factor for worse clinical course of acute lower respiratory tract infection in Chilean infants with RSV infection and without chronic disease.

[Microsporidian spores in the stool specimens of toddlers, with or without diarrhea, from Tucumán, Argentina]

An investigation has been carried out from September 1995 to December 1997 to search for microsporidian spores in the stool specimens of 344 toddlers aged 1 to 24 months, hospitalized at a pediatric institution in Tucumán. They were classified in two groups: I, made up of 222 children suffering from severe diarrheas, and II by 122 affected by different pathologies, except gastroenteritis. The detection of microsporidia was done by light microscopy in smears of stained stool specimens by using the Weber modified Kokoskin method. Copro-parasitological and coprobacteriological studies were also carried out and the nutritional status of each child was determined. In group I, microsporidia were found in 12/122 cases (7.2%), 4/68 belong to eutrophic children (5.9%), and 12/137 to undernourished children (8.8%); 8/16 positives were found to be related with other enteropatogenics. In group II, microsporidia were detected in 10/122 (8.2%), 4/47 in eutrophic children (8.5%), 4/54 in undernourished children (7.4%) and without data in two cases. They were related with other enteropatogenics in 5/10 positives. Tucumán can be estimated as an area with a low rate of HIV infection in toddlers, then it can be estimated that the studied sample was essentially HIV negative. The occurrence of microsporidia was important and did not show significant differences between toddlers with or without diarrhea, eutrophic or undernourished children.

[Estimating height and body weight from knee height and mid arm circumference in children 9 to 14 years old]

Some individuals with functional limitations or in some clinical or field areas have troubles to get stature and body weight measurement done. It does exist the alternative of estimating these variables from measurements of body segments like knee height (KH) and mid arm circumference (MAC). Of a sample of 113 healthy Venezuelan children, both sexes, 9 to 14 years of age, equations suggested by Ross Laboratories for estimating stature and body weight were applied. It was concluded that the need for an adjustment was evident which done using multiple regression analysis. This allowed us to generate estimated stature an weight by KH and MAC tables, for Venezuelan children.

[Obtaining antibodies and development of an immunoassay for the detection of Escherichia coli proteins in preparations of human recombinant gamma interferon]

The present paper refers to the obtainment of polyspecific antisera directed against Escherichia coli host strain used to produce recombinant human gamma interferon (rec. hum. gamma IFN). The antisera were obtained by the cascade immunization method. The animals (n = 3) were initially immunized with an E. coli protein preparation (EcPp) of the host strain obtained from a blank run which assures the absence of the rec. hum. gamma IFN protein. Afterwards, consecutive immunizations were carried out with the less immunogenic proteins. To obtain those proteins, EcPp is passed through a column containing antibodies purified from previous inoculations coupled to a gel matrix. In this way, the proteins that have not been recognized by the immune system in that moment (e.g. do not have their corresponding antibodies coupled to the column) are separated an used to reimmunize the animals. The analyses of the antisera by Western blotting show a progressive recognition of the host strain proteins by the antisera with the progression of the cascade method. The recognition is evident through all the molecular weight range. Those antisera were used as quality control of the recombinant protein, by quantification of the host strain protein contaminants using a multiantigenic ELISA. The detection limit of that system was 3.125 ng/mL and the quantification limit 6.25 ng/mL.