Impact of maternal obesity on preterm delivery in patients with cervical cerclage

BACKGROUND

Maternal obesity has risen in the United States in recent decades.

OBJECTIVE

This study aimed to evaluate the impact of maternal obesity on the risk for spontaneous preterm delivery and the risk for overall preterm delivery among patients with cervical cerclage placement.

STUDY DESIGN

This was a retrospective study in which data from the California Office of Statewide Health Planning and Development linked birth file from 2007 to 2012 were used, yielding a total of 3654 patients with and 2,804,671 patients without cervical cerclage placement. Exclusion criteria included patients with missing information on body mass index, multiple gestation, anomalous pregnancies, and gestations <20 weeks or >42 weeks. Patients in each group were identified and were further categorized based on body mass index with the nonobese group defined as having a body mass index of <30 kg/m², the obese group defined as having a body mass index of 30 to 40 kg/m², and the morbidly obese group defined as having a body mass index >40 kg/m². The risks for overall and spontaneous preterm delivery were compared between patients without obesity and those with obesity or those with morbid obesity patients. The analysis was stratified by cerclage placement.

RESULTS

Among patients who underwent cerclage placement, the risk for spontaneous preterm delivery was not significantly different in the obese and morbidly obese group when compared with the nonobese group (24.2% vs 20.6%; adjusted odds ratio, 1.18; 95% confidence interval, 0.97-1.43; and 24.5% vs 20.6%; adjusted odds ratio, 1.12; 0.78-1.62, respectively). However, among patients without cerclage placement, the obese and morbidly obese groups had a higher risk for spontaneous preterm delivery than the nonobese group (5.1% vs 4.4%; adjusted odds ratio, 1.04; 1.02-1.05; and 5.9% vs 4.4%; adjusted odds ratio, 1.03; 1.00-1.07, respectively). The risks for overall preterm delivery at <37 weeks' gestation were higher for the obese and morbidly obese groups than for the nonobese group among patients with cerclage (33.7% vs 28.2%; adjusted odds ratio, 1.23; 1.03-1.46; and 32.1% vs 28.2%; adjusted odds ratio, 1.01; 0.72-1.43, respectively). Similarly, among patients without cerclage placement, the risks for preterm delivery at <37 weeks' gestation were higher for the obese and morbidly obese groups than for the nonobese group (7.9% vs 6.8%; adjusted odds ratio, 1.05; 1.04-1.06; and 9.3% vs 6.8%; adjusted odds ratio, 1.10; 1.08-1.13, respectively).

CONCLUSION

Among patients who received a cervical cerclage for the prevention of preterm birth, obesity was not associated with an increased risk for spontaneous preterm delivery. However, it was associated with an overall increased risk for preterm delivery.

Severe maternal morbidity associated with endometriosis: a population based retrospective cohort study

OBJECTIVE

To evaluate the association between endometriosis and risk of severe maternal morbidity as defined by the Center for Disease Control and Prevention (CDC).

DESIGN

This was a population based retrospective cohort study using The California Office of Statewide Health Planning and Development (OSHPD) Linked Birth File with hospital discharge International Classification of Diseases, 9^th Revision, Clinical Modification (ICD-9-CM) diagnoses between 2007 and 2012.

PARTICIPANTS

3,098,578 pregnancies from 2007 to 2012 EXPOSURE: Prior diagnosis of endometriosis identified by ICD-9 codes 617.0-617.9.

MAIN OUTCOME AND MEASURES

The primary outcome of interest was severe maternal morbidity, which was defined as having been diagnosed with any of the ICD-9 codes corresponding to the 25 peripartum conditions listed by the CDC. Secondary outcomes of interest were each individual condition.

RESULTS

Of the 3,098,578 pregnancies analyzed, there were 2,910 pregnancies among women with a prior diagnosis of endometriosis. There were 45,655 pregnancies complicated by at least one severe maternal morbidity; 158 (54.3 per 1,000 pregnancies) were in pregnancies with endometriosis and 45,497 (14.7 per 1,000 pregnancies) were in pregnancies without endometriosis. Pregnancies complicated by endometriosis were 2.41 times as likely to develop severe maternal morbidity when compared to women who did not have endometriosis (aOR=2.41, 95% CI 2.03-2.87). There was increased risk of disseminated intravascular coagulation (aOR=2.46, 95% CI 1.65-3.66), heart failure during procedure or surgery (aOR=2.58, 95% CI 1.69-3.94), pulmonary edema (aOR=3.02, 95% CI 1.11-8.17), blood transfusion (aOR=2.17, 95% CI 1.75-2.68), and hysterectomy (aOR=2.46, 95% CI 1.58-3.85). When the association was stratified by delivery mode, risk of severe maternal morbidity was higher for vaginal delivery (aOR=4.59, 95% CI 2.73-7.71) versus cesarean delivery (aOR=1.64, 95% CI 1.37-1.97) (p-interaction <0.0001).

CONCLUSION

This study demonstrated that endometriosis is a major risk factor for severe maternal morbidity especially among those who deliver vaginally. Furthermore, precautions should be taken prior to delivery in anticipation of potential complications.

Comparison of skin and shoe marker placement on metatarsophalangeal joint kinematics and kinetics during running

This study investigated the effects of marker placement (skin- vs shoe-mounted) on metatarsophalangeal joint (MTP) kinematics and kinetics during running. Fifteen trained men ran on a 15-m track at 10 and 13 km/h with three (low, standard and high stiffness) shoe longitudinal bending stiffnesses (LBS). Reflective markers were fixed on the shoe upper, and on the skin using holes cut in the shoe. Three-dimensional marker positions and ground reaction forces were recorded at 200 and 2000 Hz, respectively. Kinematic and kinetic parameters were analyzed using one-dimensional metrics (statistical parametric mapping). MTP joint was less dorsiflexed at midstance ([57% to 100%] of braking phase and [0% to 48%] of pushing phase), and the MTP joint plantarflexion moment was higher ([22% to 55%] of pushing phase) with the shoe markerset in comparison with the skin markerset. The effect of LBS on MTP angle was found to be significant for a larger percentage of each stride using the shoe markerset compared to the skin markerset. However, the effect of LBS on plantarflexion moment was significant with the shoe markerset only. The effect of running speed on MTP angle was significant for a larger percentage of each stride with the skin markerset. This study demonstrates that the placement of markers influences the measurement of MTP kinematics and kinetics and that these effects are mediated by other variables such as LBS or running speed. It is concluded that the shoe markerset does not fully reflect the movement of the MTP joint.

An innovative cardiac rehabilitation based on the power-force-velocity profile to further improve cardiorespiratory capacities in coronary artery disease patients

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Doctoral contract 2018-2022

Background

Several studies have shown the importance of the relationship between the power-force-velocity profile (PFVP) and sport performance in elite athletes through optimised exercise training.[1] Optimising the training programme is constantly sought in rehabilitation among patients always younger with coronary artery disease. Nowadays, it is well established that intermittent training should be offered to coronary patients during the rehabilitation cycle.[2] In this continuity, the assessment of the PFVP at the beginning of the cardiac rehabilitation (CR) would allow to better adapt the CR training programme for each patient.

Purpose

The aim of this study was to compare the effects of two exercise training programmes: a traditional CR versus a new CR relied on patient’s PFVP on cardiorespiratory, functional and autonomic systems in coronary patients.

Methods

This prospective randomized controlled trial was conducted from May 2020 to July 2021 in an university hospital. A total of 89 patients were randomly assigned (1:1) to test or control group. Before starting CR, participants performed two sprints of 8 s on a cycle ergometer to define the PFVP. The PFVP was analysed to determine whether the participant had a force or velocity deficit. Patients included in test group followed a specific cycling training programme based on their weak point (i.e., specific force training with high resistance and low pedalling frequency on the cycle if the PFVP was oriented in velocity and reversely). While control patients attended a conventional CR programme.

The 3-week training intervention consisted of 40 min of cycling, 30 min of walking on treadmill and 20 min of strength training (4/week).

Cardiopulmonary exercise test (VO2 at the first ventilatory threshold, SV1 and VO2 peak in ml/min/kg), functional assessments (distance of 6-min walk test, handgrip strength, 10 sit-to-stand repetitions, cholesterol levels, LDL-C and quality of life) and autonomic nervous system (heart rate variability and sensitivity baroreflex) were performed at the baseline and after CR.

A two-way ANOVA with one repeated measure (pre vs. post) and one independent factor (test vs. control) was realized.

Results

The mean age was 61.0 ± 9.6 years, 18% were women. A significant difference was observed in VO2 peak (test: +22.0 ± 19.1% vs. control: +10.2 ± 15.8%, p=0.003) and VO2 SV1 (test: +35.9 ± 33.9% vs. control: +11.9 ± 34.4%, p&lt;0.001), LDL-C (p=0.016) and quality of life (p&lt;0.001). No significant change between groups in other functional tests and autonomic activity occurred after CR programme.

Conclusion

Cardiopulmonary activity, cholesterol and quality of life were improved after 3-week exercise programme. The novel CR depending on initial PFVP showed greater cardiorespiratory benefits than a conventional CR. Therefore, the PFVP can be used in CR to adapt specifically the content of training sessions.

S-Nitrosation of Arabidopsis thaliana Protein Tyrosine Phosphatase 1 Prevents Its Irreversible Oxidation by Hydrogen Peroxide

Tyrosine-specific protein tyrosine phosphatases (Tyr-specific PTPases) are key signaling enzymes catalyzing the removal of the phosphate group from phosphorylated tyrosine residues on target proteins. This post-translational modification notably allows the regulation of mitogen-activated protein kinase (MAPK) cascades during defense reactions. Arabidopsis thaliana protein tyrosine phosphatase 1 (AtPTP1), the only Tyr-specific PTPase present in this plant, acts as a repressor of H₂O₂ production and regulates the activity of MPK3/MPK6 MAPKs by direct dephosphorylation. Here, we report that recombinant histidine (His)-AtPTP1 protein activity is directly inhibited by H₂O₂ and nitric oxide (NO) exogenous treatments. The effects of NO are exerted by S-nitrosation, i.e., the formation of a covalent bond between NO and a reduced cysteine residue. This post-translational modification targets the catalytic cysteine C265 and could protect the AtPTP1 protein from its irreversible oxidation by H₂O₂. This mechanism of protection could be a conserved mechanism in plant PTPases.

Impact of labor induction at 39 weeks gestation compared with expectant management on maternal and perinatal morbidity among a cohort of low-risk women

OBJECTIVE

To determine maternal and perinatal outcomes after induction of labor (IOL) at 39 weeks compared with expectant management.

METHODS

This is a retrospective national cohort study from the National Center for Health Statistics birth database. The study included singleton, low-risk pregnancies with a non-anomalous fetus delivered at 39-42 weeks gestation between 2015 and 2018. Maternal outcomes available included chorioamnionitis (Triple I), blood transfusion, intensive care unit (ICU) admission, uterine rupture, cesarean delivery (CD), and cesarean hysterectomy. Fetal and infant outcomes included stillbirth, 5-min Apgar ≤3, prolonged ventilation, seizures, ICU admission, and death within 28 days. We compared women undergoing IOL at 39 weeks to those managed expectantly. Non-adjusted and adjusted relative risks (aRRs) were estimated using multivariate log-binomial regression analysis.

RESULTS

There were 15,900,956 births available for review of which 5,017,524 met inclusion and exclusion criteria. For the maternal outcomes, the IOL group was less likely to require a CD (aRR 0.880; 95% CI [0.874-0.886]; p value < .01) or develop Triple I (aRR 0.714; 95% CI [0.698-0.730]; p value < .01) but demonstrated a small increase in the cesarean hysterectomy rate (aRR 1.231; 95% CI [1.029-1.472]; p value < .01). Among perinatal outcomes, the stillbirth rate (aRR 0.195; 95% CI [0.153-0.249]; p value < .01), 5-min Apgar ≤3 (aRR 0.684; 95% CI [0.647-0.723]; p value < .01), prolonged ventilation (aRR 0.840; 95% CI [0.800-0.883]; p value < .01), neonatal intensive care (NICU) admission (aRR 0.862; 95% CI [0.849-0.875]; p value < .01) were lower after 39 week IOL compared with expectant management. There were no differences in risk for neonatal seizures (aRR 0.848; 95% CI [0.718-1.003]; p value 0.011) or death (aRR 1.070; 95% CI [0.722-1.586]; p value 0.660).

CONCLUSIONS

IOL at 39 weeks of gestation in a low-risk cohort is associated with a lower risk of CD and maternal infection, stillbirth, and lower neonatal morbidity. There was no effect on the risk for neonatal seizures or death.

Nitric oxide production and signalling in algae

Nitric oxide (NO) was the first identified gaseous messenger and is now well established as a major ubiquitous signalling molecule. The rapid development of our understanding of NO biology in embryophytes came with the partial characterization of the pathways underlying its production and with the decrypting of signalling networks mediating its effects. Notably, the identification of proteins regulated by NO through nitrosation greatly enhanced our perception of NO functions. In comparison, the role of NO in algae has been less investigated. Yet, studies in Chlamydomonas reinhardtii have produced key insights into NO production through the identification of NO-forming nitrite reductase and of S-nitrosated proteins. More intriguingly, in contrast to embryophytes, a few algal species possess a conserved nitric oxide synthase, the main enzyme catalysing NO synthesis in metazoans. This latter finding paves the way for a deeper characterization of novel members of the NO synthase family. Nevertheless, the typical NO-cyclic GMP signalling module transducing NO effects in metazoans is not conserved in algae, nor in embryophytes, highlighting a divergent acquisition of NO signalling between the green and the animal lineages.

Peripheral vascular disease and/or need for dialysis predicts mortality in acute myocardial infarction with shock treated with mechanical circulatory support

Background

Acute myocardial infarction (AMI) with left ventricular systolic dysfunction remains the largest cause for cardiogenic shock (CS) admissions. Aside for prompt revascularization few therapies have been shown to improve survival in this patient population. In the last decade, the use of mechanical circulatory support devices (MCS) for CS has increased, despite little evidence guiding their use.

Purpose

To explore for different baseline factors which may favor treatment with MCS vs pharmacological circulatory support (PCS) in AMI related CS.

Methods

Baseline clinical and procedural variables were retrospectively collected for all patient presenting to the cardiac cath lab with an AMI and CS at a large health care system. Patients were stratified by whether they received MCS or only PCS. The outcomes of interest were 30 day and one year mortality.

Results

Between 01/2014 andv08/2018, 205 patients presented to the cath lab with an AMI complicated by CS. The vast majority of cases were STEMIs (133/205, 65%). Overall mortality for the cohort at 30 days and one year were 41% and 50% respectively. There was no difference in 30 day or 1 year mortality between the MCS and PCS groups. A STEMI presentation was associated with increase 30 day mortality in the MCS group but the association was not seen at one year. Interestingly having a prior history peripheral vascular disease (PVD) and/or being on dialysis prior to the procedure was predictive of one year mortality in the MCS group (OR 3.8, 1.4–10.6, p=0.006) but not in the PCS.

Conclusion

Patients presenting with AMI complicated by CS have a high mortality despite successful revascularization. In our cohort having PVD and/or needing dialysis was predictive of mortality in patients receiving MCS. Patient selection is an important factor in choosing appropriate circulatory support, further prospective studies are needed.

Figure 1

Funding Acknowledgement

Type of funding source: None

Effects of the foot strike pattern on muscle activity and neuromuscular fatigue in downhill trail running

Minimizing musculo-skeletal damage and fatigue is considered paramount for performance in trail running. Our purposes were to investigate the effects of the foot strike pattern and its variability on (a) muscle activity during a downhill trail run and (b) immediate and delayed neuromuscular fatigue. Twenty-three runners performed a 6.5-km run (1264 m of negative elevation change). Electromyographic activity of lower-limb muscles was recorded continuously. Heel and metatarsal accelerations were recorded to identify the running technique. Peripheral and central fatigue was assessed in knee extensors (KE) and plantar flexors (PF) at Pre-, Post-, and 2 days post downhill run (Post2d). Anterior patterns were associated with (a) higher gastrocnemius lateralis activity and lower tibialis anterior and vastus lateralis activity during the run and (b) larger decreases in KE high-frequency stimulus-evoked torque Post and larger decrements in KE MVC Post2d. High patterns variability during the run was associated with (a) smaller decreases in KE Db100 Post and MVC Post2d and (b) smaller decreases in PF MVC Post and Post2d. Anterior patterns increase the severity of KE peripheral fatigue. However, high foot strike pattern variability during the run reduced acute and delayed neuromuscular fatigue in KE and PF.

Abstracts of the 24th international isotope society (UK group) symposium: synthesis and applications of labelled compounds 2015

The 24th annual symposium of the International Isotope Society's United Kingdom Group took place at the Møller Centre, Churchill College, Cambridge, UK on Friday 6th November 2015. The meeting was attended by 77 delegates from academia and industry, the life sciences, chemical, radiochemical and scientific instrument suppliers. Delegates were welcomed by Dr Ken Lawrie (GlaxoSmithKline, UK, chair of the IIS UK group). The subsequent scientific programme consisted of oral presentations, short 'flash' presentations in association with particular posters and poster presentations. The scientific areas covered included isotopic synthesis, regulatory issues, applications of labelled compounds in imaging, isotopic separation and novel chemistry with potential implications for isotopic synthesis. Both short-lived and long-lived isotopes were represented, as were stable isotopes. The symposium was divided into a morning session chaired by Dr Rebekka Hueting (University of Oxford, UK) and afternoon sessions chaired by Dr Sofia Pascu (University of Bath, UK) and by Dr Alan Dowling (Syngenta, UK). The UK meeting concluded with remarks from Dr Ken Lawrie (GlaxoSmithKline, UK).

Acute and delayed peripheral and central neuromuscular alterations induced by a short and intense downhill trail run

Downhill sections are highly strenuous likely contributing to the development of neuromuscular fatigue in trail running. Our purpose was to investigate the consequences of an intense downhill trail run (DTR) on peripheral and central neuromuscular fatigue at knee extensors (KE) and plantar flexors (PF). Twenty-three runners performed a 6.5-km DTR (1264-m altitude drop) as fast as possible. The electromyographic activity of vastus lateralis (VL) and gastrocnemius lateralis (GL) was continuously recorded. Neuromuscular functions were assessed Pre-, Post-, and 2-day Post-DTR (Post2d). Maximal voluntary torques decreased Post (∼ -19% for KE, ∼ -25% for PF) and Post2d (∼ -9% for KE, ∼ -10% for PF). Both central and peripheral dysfunctions were observed. Decreased KE and PF voluntary activation (VA), evoked forces, VL M-wave amplitude, and KE low-frequency fatigue were observed at Post. Changes in VL M-wave amplitude were negatively correlated to VL activity during DTR. Changes in PF twitch force and VA were negatively correlated to GL activity during DTR. The acute KE VA deficit was about a third of that reported after ultramarathons, although peripheral alterations were similar. The prolonged force loss seems to be mainly associated to VA deficit likely induced by the delayed inflammatory response to DTR-induced ultrastructural muscle damage.

Influence of Ergometer Design on Physiological Responses during Rowing

The aim of this study was to compare the physiological responses and rowing efficiency on 2 different rowing ergometers: stationary vs. dynamic ergometers manufactured by Concept2. 11 oarswomen and oarsmen rowed 4 min at 60% and 70% of peak power output on both ergometers (randomized order). Power output, stroke rate, heart rate, oxygen uptake, carbon dioxide production, lactate accumulation and rating of perceived exertion were recorded at each stage on the 2 ergometers. Gross and net efficiencies were computed. Exercise intensity was associated with increases in all parameters. Rowing on dynamic ergometer was associated with higher heart rate, oxygen uptake, carbon dioxide production and stroke rate, concomitantly to lower blood lactate accumulation but also to lower gross and net efficiencies. The present study showed that rowing efficiency and blood lactate accumulation were lower on the Concept2 dynamic ergometer than on its stationary counterpart. If the use of the Concept2 dynamic ergometer may provide some advantages (reduced risk of injuries), its utilization requires a specific evaluation of physiological responses during an incremental exercise for an adapted management of training.

Influencing weight bias: The impact of biased questionnaire anchors on stereotype beliefs and judgments

OBJECTIVES

In this investigation, biased questionnaire response anchors were designed to indirectly manipulate respondents' estimates of their peers' stereotypic beliefs or the estimates of scientific research findings about individuals with obesity. The current study tested the hypothesis that biased response anchors could influence personal beliefs about obesity.

METHODS

Two-hundred adults participated in the study. A simple manipulation of questionnaire items (i.e., asking respondents to estimate peers' beliefs or scientific research findings) using biased response scale anchors was designed to subtly relay information about certain personality traits of individuals with obesity.

RESULTS

The anchor manipulation significantly influenced participants' immediate and follow-up weight biased beliefs as well as participants' evaluation of an obese job applicant's potential for employment.

CONCLUSION

Social judgments about obese individuals may be susceptible to subtle manipulation of response anchors and may be impacted by the source of comparison information (e.g., peers; scientific research).

The sourdough microflora. Interactions between lactic acid bacteria and yeasts: metabolism of amino acids

Co-culture of Lactobacillus brevis subsp. lindneri or L. plantarum with Saccharomyces cerevisiae or S. exiguus from sourdough did not modify the yield of the yeasts but gave higher growth rates and final yields of both lactic acid bacteria (LAB) than in their respective mono-cultures. Co-cultures of L. brevis subsp. lindneri with S. cerevisiae or S. exiguus in a medium without valine or leucine, which are essential for growth of the LAB, led to growth of the LAB due to excretion of these amino acids by the yeasts.

Learning safe practice by improving care: student-led intervention on oxygen prescribing in a respiratory ward

BACKGROUND AND OBJECTIVE

The primary aim of this intervention was to improve oxygen prescribing in accordance with the 2008 British Thoracic Society guidelines for the prescription of emergency oxygen in adults.

METHODS

Eight final year medical students reviewed the drug charts of all patients admitted to the respiratory ward on a daily basis in order to collect data on five audit questions: (1) Has oxygen (O2) been prescribed? (2) Has an O2 target saturation level been indicated? (3) Has O2 been prescribed as an 'as required' (PRN) or 'continuous therapy'? (4) Has the prescription been signed? (5) Has O2 been signed for in every drug round since the original prescription? Following an initial audit cycle an educational poster was distributed to all clinical staff via email and hard copies of the poster were placed strategically throughout the ward before its effectiveness was measured.

RESULTS

During the pre-intervention phase, compliance with all five measures varied from 0 to 25%. There was an increase in the variation in compliance after the poster intervention to 14-44%; however, this masked better overall compliance with all five investigative questions with figures of 44%, 39% and 42% being recorded in three of the four post-intervention days. Overall there was increased compliance with four of the five audit questions. Indeed compliance with question 3 rose from 14% to 83%.

CONCLUSIONS

The poster intervention was marginally effective while also showing that students can improve prescribing in a clinical setting.

228 IN VITRO EMBRYO PRODUCTION AFTER EXPOSURE OF BOVINE OOCYTES TO DIFFERENT TRANSPORTATION MEDIA AND PERIODS: PRELIMINARY RESULTS

This study was designed to evaluate the effect of different oocyte transportation media and time. Immature oocytes were recovered from slaughterhouse bovine ovaries. Oocytes (n = 492) of quality grades I to III were randomly allotted to one of the following transportation media based on TCM-199, either buffered with HEPES (control) or buffered with NaHCO3 and added with FSH/LH (maturing). Both media were supplemented with pyruvate, penicillin G (10 000 IU), streptomycin (0.05 mg mL–1), and 10% fetal bovine serum (FBS). In control medium, the oocytes were kept for 1 or 8 h at 37°C, and thereafter were transferred to maturing medium until the maturation period (24 h) was completed, under controlled atmosphere (5% CO2) and temperature, in an incubator. The maturing oocytes were distributed in two types of equipment developed for oocyte and embryo transportation, with and without 5% CO2, and kept for 1, 8, or 24 h before maturation or fecundation (IVF) procedures. The oocytes kept for 24 h in the transportation device were placed directly for IVF. All procedures used for in vitro maturation, IVF, and in vitro culture were the same as those adopted for commercial in vitro embryo production at Biotran LTDA (Alfenas, Minas Gerais, Brazil). The cleavage rate was evaluated on Day 3 post-insemination, and the blastocyst production was evaluated on Day 7. The statistical model included the main effects of treatment (control and maturing with or without 5% CO2), time, replicate, and the interaction of media × time. Data (3 replicates) were analysed by ANOVA and differences were identified by Tukey’s test. The time before in vitro maturation at the incubator negatively (P < 0.007) affected cleavage rates (76.4 ± 16.9 v. 58.8 ± 13.2 and 52.2 ± 18.5%, respectively, for 1, 8, and 24 h). However, treatment had no effects (P = 0.3) on cleavage (66.9 ± 15.0, 57.8 ± 19.7, and 67.7 ± 19.8% for the control and maturation with and without 5% CO2, respectively). Similarly, blastocyst production rates differed (P < 0.04) between 1 h (33.4 ± 14.7) and 24 h (19.3 ± 17.0%), whereas blastocyst production at 8 h did not show significant effects (19.3 ± 17.0). Although it was not significant (P > 0.05), only 14.1% of the oocytes kept in medium 2 with a controlled atmosphere for 24 h became embryos. This difference was probably related to the trend in treatment effect (P = 0.06) and the lower rate of embryo production (22.2 ± 13.6%) in this treatment compared with the control (33.8 ± 18.1%) and maturation without 5% CO2 (29.8 ± 17.3%). These results showed that 24 h of transportation is detrimental for the oocyte development potential and that the buffered medium used in this study with 5% CO2 did not efficiently maintain embryo production. Supported by CNPq, CAPES, FAPEMIG, and Biotran LTDA.

Evaluation of a computer-assisted navigation system for anterior cruciate ligament reconstruction: prospective non-randomized cohort study versus conventional surgery

BACKGROUND

Conventional reconstruction of the anterior cruciate ligament (ACL) is associated with a 15% failure rate. Computer-assisted navigation systems (CANS) have been developed to improve the accuracy of tunnel positioning.

HYPOTHESIS

The use of a CANS for ACL reconstruction decreases the rate of failure, defined as IKDC grade C or D, compared to conventional ACL reconstruction.

MATERIALS AND METHODS

This prospective multicentre observational non-randomised open study compared two groups of patients requiring arthroscopic ACL reconstruction: one group was managed with a CANS and the other (control group) without a CANS. The primary evaluation criterion was based on the subjective and objective IKDC scores. Inclusion criteria were age older than 18 years and first ACL reconstruction procedure using autologous semitendinosus and gracilis tendons or an autologous bone-patellar tendon-bone graft. Of the 272 included patients, 214 were analysed; 100 were in the control group and 114 in the CANS group.

RESULTS

No significant between-group differences were found for the fraction of patients having an IKDC grade A or B (P=0.953), the subjective IKDC score (P=0.77), differential knee laxity at 150 N (1.38 ± 1.79 mm in the control group and 1.77 ± 2.06 mmin the CANS group, P=0.384), graft-type, or graft positioning.

DISCUSSION

Our results establish the large-scale feasibility of computer-assisted navigation for ACL reconstruction. However, the main outcomes at 1 year showed no significant differences between patients managed with and without computer-assisted navigation.

Melanocortin-3 receptors are involved in adaptation to restricted feeding

The central nervous melanocortin system forms a neural network that maintains energy homeostasis. Actions involving neural melanocortin-3 receptors (MC3Rs) regulate the expression rhythms in ingestive behaviors and metabolism anticipating nutrient intake. Here, we characterized the response of Mc3r knockout (Mc3r(-/-)) and wild type (WT) mice to a restricted feeding (RF) schedule where food access was limited to a 4-h period mid light cycle using a mechanical barrier. Mc3r(-/-) mice adapted poorly to the food restriction schedule. Anticipatory activity and the initial bout of intense feeding activity associated with granting food access were attenuated in Mc3r(-/-) mice, resulting in increased weight loss relative to controls. To investigate whether activity in specific hypothalamic nuclei contribute to the Mc3r(-/-) phenotype observed, we assessed hypothalamic FOS-immunoreactivity (FOS-IR) associated with food restriction. Food access markedly increased FOS-IR in the dorsomedial hypothalamus (DMH), but not in the suprachiasmatic or ventromedial hypothalamic nuclei (SCN and VMN, respectively) compared to ad libitum fed mice. Mc3r(-/-) mice displayed a significant reduction in FOS-IR in the DMH during feeding. Analysis of MC3R signaling in vitro indicated dose-dependent stimulation of the extracellular signal-regulated kinase (ERK) pathway by the MC3R agonist d-Trp(8)-γMSH. Treatment of WT mice with d-Trp(8)-γMSH administered intracerebroventricularly increased the number of pERK neurons 1.7-fold in the DMH. These observations provide further support for the involvement of the MC3Rs in regulating adaptation to food restriction. Moreover, MC3Rs may modulate the activity of neurons in the DMH, a region previously linked to the expression of the anticipatory response to RF.

Analysis of anatomic positioning in computer-assisted and conventional anterior cruciate ligament reconstruction

INTRODUCTION

Anterior cruciate ligament (ACL) reconstruction should be anatomic while achieving favorable anisometric behavior to avoid impingement with the femoral notch. Computerization enables these biomechanical conditions to be optimally fulfilled; but what of anatomic positioning? The present study compared the positioning of tibial and femoral tunnels, drilled using either a conventional ACL guide or a navigation system, using the anatomic foot-print areas of the native ACL.

MATERIAL AND METHODS

This cadaver study used computerized recording to compare tibial and femoral ACL attachment areas to the positioning of tunnels created either conventionally or under computer-guided navigation.

RESULTS

Computer guidance enabled the tibial and femoral tunnels to be systematically positioned within the anatomic area and, as regards the tibial area, within the anterior third near to the medial tibial spine, without femoral notch impingement. Anisometry was in all cases favorable, at a mean 3.3 ± 0.7 mm; using a conventional guide, anisometry was favorable in only 50% of cases, at a mean 5.4 ± 1.2 mm.

CONCLUSION

Computer-guided navigation ensured implant positioning within the so-called anatomometric area of the native ACL attachment, avoiding impingement with the femoral notch.

LEVEL OF EVIDENCE

Level 2.

Inhibition of Grb2 expression demonstrates an important role in BCR-ABL-mediated MAPK activation and transformation of primary human hematopoietic cells

Chronic myeloid leukemia (CML) results from the expression of the BCR/ABL oncogene in a primitive hematopoietic cell. However, BCR/ABL-activated signaling mechanisms are dependent on the cellular context in which it is expressed, and mechanisms underlying primitive human hematopoietic cell transformation by BCR-ABL are not well understood. Our previous studies have shown that BCR/ABL-Y177 has an essential role in Ras activation and human hematopoietic progenitor transformation in CML. The adapter protein growth factor receptor-binding protein-2 (Grb2) can bind phosphorylated BCR/ABL-Y177, induce Grb2-SoS complex formation and activate Ras signaling. We investigated the role of Grb2 in CML progenitor transformation by cotransducing human CD34+ cells with lentivirus vectors expressing short hairpin RNA to Grb2 and retrovirus vectors expressing BCR/ABL. We show that Grb2 knockdown significantly inhibits proliferation and survival of BCR-ABL-expressing CD34+ cells, but not control CD34+ cells. Grb2 knockdown reduced mitogen-activated protein kinase (MAPK) activity in BCR-ABL-expressing hematopoietic cells. We conclude that inhibition of Grb2 expression demonstrates an important role in BCR-ABL-mediated MAPK activation and transformation of primary human hematopoietic cells.These results support further investigation of downstream effectors of Grb2-mediated signals and targeting of Grb2 interactions in the treatment of CML.

Anterior cruciate ligament reconstruction: assessment of the hamstring autograft femoral fixation using the EndoButton CL

The objective of this study was to evaluate the clinical and radiological results of a prospective, continuous series of 105 ACL reconstructions using the STG tendons fixed to the femur by an EndoButton CL, with more than 4 years of follow-up.

HYPOTHESIS

The subjective and objective clinical results as well as the radiological results (tunnel enlargement) obtained by a cortical, extra-anatomic femoral fixation are at least equivalent to the results obtained with other types of femoral fixation systems.

MATERIAL AND METHODS

One hundred and five patients aged with a mean 26 years (range, 12-56 years) were operated on for an anterior cruciate ligament rupture using the same technique and by the same operator: four-strand STG fixed to the tibia by a double fixation--BioRCI-HA screw and staple--and on the femur by an EndoButton CL (Smith and Nephew). The results were assessed at 6 months, 1 and 2 years and then at a mean follow-up of 51 months, both clinically (IKDC, Lysholm, KT-1000) and radiologically (Telos laximetry, tunnel position, and morphological analysis).

RESULTS

No complications related to the use of the EndoButton were observed. No additional interference screw was necessary. According to the IKDC laxity classification, 91.4% of the patients were classified in category A or B, nine knees (8.6%) were classified C or D. Four failures required revision with a patellar tendon graft. On the final IKDC score, 63 patients (60%) were classified grade A, 37 grade B (35.3%), four grade C (3.8%), and one grade D (0.9%). On the Telos laximetry, 62 patients (59%) had a differential laxity less than or equal to 2 mm. The mean value was 1.8 mm (range, 0-11). Tibial tunnel enlargement was constant; femoral tunnel enlargement was significant (>2 mm) in 27.6% of the knees. No femoral tunnel diameter modification corresponding to the EndoButton passage was observed.

DISCUSSION

The results of this series are comparable to the results of other series. Its reproducibility and the absence of iatrogenic complications for this femoral EndoButton CL fixation make it a top-choice technique, like the corticocancellous graft procedures, but without their disadvantages. No secondary elongation attributable to the EndoButton CL was observed. This femoral fixation procedure appeared necessary and sufficient to providing good mechanical stability for the graft in the femoral tunnel.

CNTO328 (Anti-IL-6 mAb) treatment and hemoglobin (Hb) levels in renal cell cancer

e20648

Background: CNTO328 is a chimeric monoclonal antibody against the inflammatory cytokine, IL-6, which is currently being studied in hematologic and solid malignancies. IL-6 is a potent inducer of hepatic production of hepcidin, which is the key regulator of iron homeostasis and causes anemia by blocking iron export from enterocytes and macrophages. Hepcidin is an important factor in the pathogenesis of ‘anemia of chronic disease‘. CNTO328 treatment has previously been shown to produce profound Hb increases in Castleman's disease, a disorder caused by deregulated IL-6 production. We subsequently conducted this retrospective review to assess whether CNTO328 treatment is associated with an increase in Hb level in renal cell cancer patients (pts). Methods: All laboratory results for pts with metastatic renal cell carcinoma in this open label phase 2 study were reviewed. Pts were treated with CNTO328 (6 mg/kg) IV infusions Q2 weeks and were evaluated for tumor response and markers of pharmacodynamic effect. The difference in Hb levels from baseline to end of study was calculated. Results: Twenty pts (19 males) with a median age of 62 yrs (range 50–77) were studied. The median number of infusions was 6 (1–13). Of 18 pts evaluable for tumor response, 11 (61%) had SD and 7 (39%) had PD. The median baseline Hb was 13.6 g/dL (10.8–17.1). Nineteen pts were evaluable for Hb response. No pts received ESAs or transfusions. Treatment with CNTO328 resulted in a sustained Hb increase in 16 of the 19 pts (84%), with 13 (68%) achieving a max Hb increase of ≥ 1 g/dL (median 1.9; range 1.0–3.5). Hb responses were early (by day 8) and independent of tumor response. No Hb overshoot or thromboembolic events were observed. A trend toward decreased platelet and neutrophil counts was observed. Conclusions: Though pts were not anemic at baseline, our results suggest that CNTO328 leads to sustained increase in Hb levels, not correlated with tumor response. This increase in Hb is presumably due to the reduction of hepcidin via IL-6 blockade and targeting the hepcidin pathway may lead to new therapies for anemia of cancer. This hypothesis warrants further evaluation with prospective mechanistic studies.

[Table: see text]

Analysis of cell surface erythropoietin receptor (EpoR) expression and function in human epithelial tumor tissues

11104

Background: EpoR mRNA and protein expression have been reported at low levels in human tumors implying EpoR may be functional in tumor cells with inferred implications for the use of erythropoiesis stimulating agents in the Oncology setting. However, mRNA studies use bulk tumor tissue which ignores contribution from the stroma and IHC studies have all used Abs that have since been shown to not be specific for EpoR. Therefore this important question remains unresolved. Methods: EpoR expression and function was investigated in viable, non-apoptotic primary human tumor cells (using tumor specific Abs) that were disaggregated from at least 30 patients from each of the following tumor types: breast (incl. metastases), NSC lung, colorectal, and ovarian. Additional tumor types included head and neck, GBM, pancreatic and gastric. Analysis was performed under conditions that were shown to preserve EpoR expression and function in positive control tissues (primary human erythroid progenitors from bone marrow and UT-7 cells). Cell surface EpoR expression was evaluated by flow cytometry using novel EpoR-specific Abs. EpoR function was investigated by analysis of EpoR signaling using phospho-specific Abs specific for STAT5, Erk, Akt etc following ex vivo Epo stimulation (0U- 300U/mL; for 5 and 30 min). Results: No expression of cell surface EpoR was detected in tumor cells in any of the over 130 tumors. In contrast, high levels of expression were observed in positive controls analyzed in parallel. No induction of EpoR signaling was observed in tumor cells at any [Epo], whereas activation was readily detected in tumor cells treated in parallel with a cocktail of known tumor growth factors. Positive controls treated in parallel, showed robust Epo concentration-dependent signaling. No evidence of EpoR expression or function was observed in tumor endothelial cells. Conclusions: These data demonstrate that epithelial tumor cells do not express functional cell surface EpoR and are not responsive to physiological, therapeutic or indeed very high levels of Epo (300U/mL).

No significant financial relationships to disclose.