Direct Observation of Polaritonic Chemistry by Nuclear Magnetic Resonance Spectroscopy.

Polaritonic chemistry is emerging as a powerful approach to modifying the properties and reactivity of molecules and materials. However, probing how the electronics and dynamics of molecular systems change under strong coupling has been challenging due to the narrow range of spectroscopic techniques that can be applied in situ. Here we develop microfluidic optical cavities for vibrational strong coupling (VSC) that are compatible with nuclear magnetic resonance (NMR) spectroscopy using standard liquid NMR tubes. VSC is shown to influence the equilibrium between two conformations of a molecular balance sensitive to London dispersion forces, revealing an apparent change in the equilibrium constant under VSC. In all compounds studied, VSC does not induce detectable changes in chemical shifts, J-couplings, or spin-lattice relaxation times. This unexpected finding indicates that VSC does not substantially affect molecular electron density distributions, and in turn has profound implications for the possible mechanisms at play in polaritonic chemistry under VSC and suggests that the emergence of collective behavior is critical.

Analysing Sources of Error in Total Internal Reflection Microscopy (TIRM) Experiments and Data Analysis.

Many phenomena observed in synthetic and biological colloidal suspensions are dominated by the static interaction energies and the hydrodynamic interactions that act both between individual particles and also between colloids and macroscopic interfaces. This calls for methods that allow precise measurements of the corresponding forces. One method used for this purpose is total internal reflection microscopy (TIRM), which has been employed for around three decades to measure in particular the interactions between a single particle suspended in a liquid and a solid surface. However, given the importance of the observable variables, it is crucial to understand the possibilities and limitations of the method. In this paper, we investigate the influence of technically unavoidable noise effects and an inappropriate choice of particle size and sampling time on TIRM measurement results. Our main focus is on the measurement of diffusion coefficients and drift velocities, as the influence of error sources on dynamic properties has not been investigated so far. We find that detector shot noise and prolonged sampling times may cause erroneous results in the steep parts of the interaction potential where forces of the order of pico-Newtons or larger act on the particle, while the effect of background noise is negligible below certain thresholds. Furthermore, noise does not significantly affect dynamic data but we find that lengthy sampling times and/or probe particles with too small a radius will cause issues. Most importantly, we observe that dynamic results are very likely to differ from the standard hydrodynamic predictions for stick boundary conditions due to partial slip.

The human mitochondrial mRNA structurome reveals mechanisms of gene expression.

The mammalian mitochondrial genome encodes thirteen oxidative phosphorylation system proteins, crucial in aerobic energy transduction. These proteins are translated from 9 monocistronic and 2 bicistronic transcripts, whose native structures remain unexplored, leaving fundamental molecular determinants of mitochondrial gene expression unknown. To address this gap, we developed a mitoDMS-MaPseq approach and used DREEM clustering to resolve the native human mitochondrial mt-mRNA structurome. We gained insights into mt-mRNA biology and translation regulatory mechanisms, including a unique programmed ribosomal frameshifting for the ATP8/ATP6 transcript. Furthermore, absence of the mt-mRNA maintenance factor LRPPRC led to a mitochondrial transcriptome structured differently, with specific mRNA regions exhibiting increased or decreased structuredness. This highlights the role of LRPPRC in maintaining mRNA folding to promote mt-mRNA stabilization and efficient translation. In conclusion, our mt-mRNA folding maps reveal novel mitochondrial gene expression mechanisms, serving as a detailed reference and tool for studying them in different physiological and pathological contexts.

Mitoribosome Biogenesis.

Mitoribosome biogenesis is a complex and energetically costly process that involves RNA elements encoded in the mitochondrial genome and mitoribosomal proteins most frequently encoded in the nuclear genome. The process is catalyzed by extra-ribosomal proteins, nucleus-encoded assembly factors that act in all stages of the assembly process to coordinate the processing and maturation of ribosomal RNAs with the hierarchical association of ribosomal proteins. Biochemical studies and recent cryo-EM structures of mammalian mitoribosomes have provided hints regarding their assembly. In this general concept chapter, we will briefly describe the current knowledge, mainly regarding the mammalian mitoribosome biogenesis pathway and factors involved, and will emphasize the biological sources and approaches that have been applied to advance the field.

Pregnancy rate and reproductive hormones in humpback whale blubber: Dominant form of progesterone differs during pregnancy.

To better understand reproductive physiology of humpback whales Megaptera novaeangliae that reside in Hawai'i and Alaska, enzyme immunoassays were validated for both progesterone and testosterone in free-ranging and stranded animals (n = 185 biopsies). Concentrations were analyzed between different depths of large segments of blubber taken from skin to muscle layers of stranded female (n = 2, 1 pregnant, 1 non-pregnant) and male (n = 1) whales. Additionally, progesterone metabolites were identified between pregnant (n = 1) and non-pregnant (n = 3) females using high pressure liquid chromatography (HPLC). Progesterone concentrations were compared between juvenile (i.e., sexually immature), lactating, and pregnant females, and male whales, and pregnancy rates of sexually mature females were calculated. Based on replicate samples from ship struck animals collected at 7 depth locations, blubber containing the highest concentration of progesterone was located 1 cm below the skin for females, and the highest concentration of testosterone was in the skin layer of one male whale. HPLC of blubber samples of pregnant and non-pregnant females contain different immunoreactive progesterone metabolites, with the non-pregnant female eluate comprised of a more polar, and possibly conjugated, form of progesterone than the pregnant female. In females, concentrations of progesterone were highest in the blubber of pregnant (n = 28, 28.6 ± 6.9 ng/g), followed by lactating (n = 16, 0.9 ± 0.1 ng/g), and female juvenile (n = 5, 1.0 ± 0.2 ng/g) whales. Progesterone concentrations in male (n = 24, 0.6 ng/g ± 0.1 ng/g) tissues were the lowest all groups, and not different from lactating or juvenile females. Estimated summer season pregnancy rate among sexually mature females from the Hawai'i stock of humpback whales was 0.562 (95 % confidence interval 0.528-0.605). For lactating females, the year-round pregnancy rate was 0.243 (0.09-0.59), and varies depending on the threshold of progesterone assumed for pregnancy in the range between 3.1 and 28.5 ng/g. Our results demonstrate the synergistic value added when combining immunoreactive assays, HPLC, and long-term sighting histories to further knowledge of humpback whale reproductive physiology.

Balanced mitochondrial and cytosolic translatomes underlie the biogenesis of human respiratory complexes.

BACKGROUND: Oxidative phosphorylation (OXPHOS) complexes consist of nuclear and mitochondrial DNA-encoded subunits. Their biogenesis requires cross-compartment gene regulation to mitigate the accumulation of disproportionate subunits. To determine how human cells coordinate mitochondrial and nuclear gene expression processes, we tailored ribosome profiling for the unique features of the human mitoribosome. RESULTS: We resolve features of mitochondrial translation initiation and identify a small ORF in the 3' UTR of MT-ND5. Analysis of ribosome footprints in five cell types reveals that average mitochondrial synthesis levels correspond precisely to cytosolic levels across OXPHOS complexes, and these average rates reflect the relative abundances of the complexes. Balanced mitochondrial and cytosolic synthesis does not rely on rapid feedback between the two translation systems, and imbalance caused by mitochondrial translation deficiency is associated with the induction of proteotoxicity pathways. CONCLUSIONS: Based on our findings, we propose that human OXPHOS complexes are synthesized proportionally to each other, with mitonuclear balance relying on the regulation of OXPHOS subunit translation across cellular compartments, which may represent a proteostasis vulnerability.

Effect of Plyometric Jump Training on Skeletal Muscle Hypertrophy in Healthy Individuals: A Systematic Review With Multilevel Meta-Analysis.

Objective: To examine the effect of plyometric jump training on skeletal muscle hypertrophy in healthy individuals. Methods: A systematic literature search was conducted in the databases PubMed, SPORTDiscus, Web of Science, and Cochrane Library up to September 2021. Results: Fifteen studies met the inclusion criteria. The main overall finding (44 effect sizes across 15 clusters median = 2, range = 1-15 effects per cluster) indicated that plyometric jump training had small to moderate effects [standardised mean difference (SMD) = 0.47 (95% CIs = 0.23-0.71); p < 0.001] on skeletal muscle hypertrophy. Subgroup analyses for training experience revealed trivial to large effects in non-athletes [SMD = 0.55 (95% CIs = 0.18-0.93); p = 0.007] and trivial to moderate effects in athletes [SMD = 0.33 (95% CIs = 0.16-0.51); p = 0.001]. Regarding muscle groups, results showed moderate effects for the knee extensors [SMD = 0.72 (95% CIs = 0.66-0.78), p < 0.001] and equivocal effects for the plantar flexors [SMD = 0.65 (95% CIs = -0.25-1.55); p = 0.143]. As to the assessment methods of skeletal muscle hypertrophy, findings indicated trivial to small effects for prediction equations [SMD = 0.29 (95% CIs = 0.16-0.42); p < 0.001] and moderate-to-large effects for ultrasound imaging [SMD = 0.74 (95% CIs = 0.59-0.89); p < 0.001]. Meta-regression analysis indicated that the weekly session frequency moderates the effect of plyometric jump training on skeletal muscle hypertrophy, with a higher weekly session frequency inducing larger hypertrophic gains [ß = 0.3233 (95% CIs = 0.2041-0.4425); p < 0.001]. We found no clear evidence that age, sex, total training period, single session duration, or the number of jumps per week moderate the effect of plyometric jump training on skeletal muscle hypertrophy [ß = -0.0133 to 0.0433 (95% CIs = -0.0387 to 0.1215); p = 0.101-0.751]. Conclusion: Plyometric jump training can induce skeletal muscle hypertrophy, regardless of age and sex. There is evidence for relatively larger effects in non-athletes compared with athletes. Further, the weekly session frequency seems to moderate the effect of plyometric jump training on skeletal muscle hypertrophy, whereby more frequent weekly plyometric jump training sessions elicit larger hypertrophic adaptations.

[Rituximab for the treatment of generalised myasthenia gravis: experience in clinical practice]. / Rituximab para el tratamiento de la miastenia grave generalizada: experiencia en la práctica clínica.

INTRODUCTION AND AIMS: Rituximab (RTX) is an anti-CD20 monoclonal antibody that has been used in cases of refractory myasthenia gravis (MG). The aim of this work is to analyse the efficacy and safety of RTX in MG in real clinical practice in a tertiary hospital. PATIENTS AND METHODS: A retrospective study was conducted with patients with MG treated with RTX in our centre from March 2014 to September 2020. Demographic and serological data, together with information about previous immunomodulatory treatment, clinical response and adverse effects are collected. RESULTS: Twenty patients with MG - 100% generalised: 70% late-onset MG (LOMG) and 30% early-onset MG (EOMG) - were given RTX (mean age: 66.8 years; 70% male). A total of 90% are seropositive, 16 of them with positive anti-acetylcholine receptor antibodies and two with positive muscle-specific tyrosine kinase (anti-MuSK) antibodies. All had failed previous treatments: 100% with steroids, 100% with intravenous immunoglobulins and/or plasmapheresis, 55% with other immunosuppressants (25% with one previous immunosuppressant, 10% with two, 15% with three and 5% with four) and 35% with thymectomy. After RTX, 75% of patients showed a clinical response (12 patients with complete remission and the possibility of steroid withdrawal without recurrence; and three patients with partial remission and the possible reduction of steroid dosage) and 25% therapeutic failure; in all these cases RTX was withdrawn. All the anti-MuSK+ patients (100%) and 92.8% of the LOMG patients responded to RTX, while 66% of EOMG patients failed. Only three patients reported adverse effects, all of which were mild and did not require RTX withdrawal. CONCLUSION: In our experience, rituximab is a safe and effective treatment in aggressive generalised MG with anti-MuSK or late-onset MG (LOMG).

TITLE: Rituximab para el tratamiento de la miastenia grave generalizada: experiencia en la práctica clínica.Introducción y objetivos. El rituximab (RTX) es un anticuerpo monoclonal anti-CD20 que se ha utilizado en casos de miastenia grave (MG) refractaria. El objetivo de este trabajo es analizar la eficacia y la seguridad del RTX en la MG en la práctica clínica real en un hospital terciario. Pacientes y métodos. Se realiza un estudio retrospectivo de pacientes con MG tratados con RTX en nuestro centro de marzo de 2014 a septiembre de 2020. Se recogen datos demográficos, serológicos, tratamiento inmunomodulador previo, respuesta clínica y efectos adversos. Resultados. Veinte pacientes con MG ­el 100%, generalizada: el 70%, MG de inicio tardío (LOMG), y el 30%, MG de inicio temprano (EOMG)­ han recibido RTX (edad media: 66,8 años; 70%, varones). El 90% son seropositivos ­16 con anticuerpos antirreceptor de la acetilcolina positivos y dos con anticuerpos antitirosincinasa muscular específica (anti-MuSK) positivos­. Todos habían fracasado con tratamientos previos: el 100% con esteroides, el 100% con inmunoglobulinas intravenosas y/o con plasmaféresis, el 55% con otros inmunosupresores (25%, un inmunosupresor previo; 10%, dos; 15%, tres; y 5%, cuatro) y el 35% con timectomía. Tras el RTX, presentó respuesta clínica el 75% de los pacientes (12 pacientes, remisión completa con posibilidad de la retirada de los esteroides sin recurrencia; y tres parcial, con posibilidad de la reducción de la dosis de esteroides) y fracaso terapéutico el 25%; en todos estos casos se retiró el RTX. El 100% de los pacientes anti-MuSK+ y el 92,8% de los de LOMG presentaron respuesta al RTX, mientras que el 66% de los pacientes con EOMG fracasaron. Sólo tres pacientes presentaron efectos adversos, todos leves, que no requirieron la retirada del RTX. Conclusión. En nuestra experiencia, el rituximab es un tratamiento seguro y eficaz en la MG generalizada agresiva con anticuerpos anti-MuSK o de inicio tardío (LOMG).

Rituximab para el tratamiento de la miastenia grave generalizada: experiencia en la práctica clínica / Rituximab for the treatment of generalised myasthenia gravis: experience in clinical practice

Introducción y objetivos: El rituximab (RTX) es un anticuerpo monoclonal anti-CD20 que se ha utilizado en casos de miastenia grave (MG) refractaria. El objetivo de este trabajo es analizar la eficacia y la seguridad del RTX en la MG en la práctica clínica real en un hospital terciario. Pacientes y métodos:Se realiza un estudio retrospectivo de pacientes con MG tratados con RTX en nuestro centro de marzo de 2014 a septiembre de 2020. Se recogen datos demográficos, serológicos, tratamiento inmunomodulador previo, respuesta clínica y efectos adversos. Resultados: Veinte pacientes con MG –el 100%, generalizada: el 70%, MG de inicio tardío (LOMG), y el 30%, MG de inicio temprano (EOMG)– han recibido RTX (edad media: 66,8 años; 70%, varones). El 90% son seropositivos –16 con anticuerpos antirreceptor de la acetilcolina positivos y dos con anticuerpos antitirosincinasa muscular específica (anti-MuSK) positivos–. Todos habían fracasado con tratamientos previos: el 100% con esteroides, el 100% con inmunoglobulinas intravenosas y/o con plasmaféresis, el 55% con otros inmunosupresores (25%, un inmunosupresor previo; 10%, dos; 15%, tres; y 5%, cuatro) y el 35% con timectomía. Tras el RTX, presentó respuesta clínica el 75% de los pacientes (12 pacientes, remisión completa con posibilidad de la retirada de los esteroides sin recurrencia; y tres parcial, con posibilidad de la reducción de la dosis de esteroides) y fracaso terapéutico el 25%; en todos estos casos se retiró el RTX. El 100% de los pacientes anti-MuSK+ y el 92,8% de los de LOMG presentaron respuesta al RTX, mientras que el 66% de los pacientes con EOMG fracasaron. Sólo tres pacientes presentaron efectos adversos, todos leves, que no requirieron la retirada del RTX. Conclusión: En nuestra experiencia, el rituximab es un tratamiento seguro y eficaz en la MG generalizada agresiva con anticuerpos anti-MuSK o de inicio tardío (LOMG).(AU)

Introduction and aims: Rituximab (RTX) is an anti-CD20 monoclonal antibody that has been used in cases of refractory myasthenia gravis (MG). The aim of this work is to analyse the efficacy and safety of RTX in MG in real clinical practice in a tertiary hospital. Patients and methods: A retrospective study was conducted with patients with MG treated with RTX in our centre from March 2014 to September 2020. Demographic and serological data, together with information about previous immunomodulatory treatment, clinical response and adverse effects are collected. Results: Twenty patients with MG – 100% generalised: 70% late-onset MG (LOMG) and 30% early-onset MG (EOMG) – were given RTX (mean age: 66.8 years; 70% male). A total of 90% are seropositive, 16 of them with positive anti-acetylcholine receptor antibodies and two with positive muscle-specific tyrosine kinase (anti-MuSK) antibodies. All had failed previous treatments: 100% with steroids, 100% with intravenous immunoglobulins and/or plasmapheresis, 55% with other immunosuppressants (25% with one previous immunosuppressant, 10% with two, 15% with three and 5% with four) and 35% with thymectomy. After RTX, 75% of patients showed a clinical response (12 patients with complete remission and the possibility of steroid withdrawal without recurrence; and three patients with partial remission and the possible reduction of steroid dosage) and 25% therapeutic failure; in all these cases RTX was withdrawn. All the anti-MuSK+ patients (100%) and 92.8% of the LOMG patients responded to RTX, while 66% of EOMG patients failed. Only three patients reported adverse effects, all of which were mild and did not require RTX withdrawal. Conclusion: In our experience, rituximab is a safe and effective treatment in aggressive generalised MG with anti-MuSK or late-onset MG (LOMG).(AU)

The effect of morphology and particle-wall interaction on colloidal near-wall dynamics.

We investigated the near-wall Brownian dynamics of different types of colloidal particles with a typical size in the 100 nm range using evanescent wave dynamic light scattering (EWDLS). In detail we studied dilute suspensions of silica spheres and shells with a smooth surface and silica particles with controlled surface roughness. While the near wall dynamics of the particle with a smooth surface differ only slightly from the theoretical prediction for hard sphere colloids, the rough particles diffuse significantly slower. We analysed the experimental data by comparison with model calculations and suggest that the deviating dynamics of the rough particles are not due to increased hydrodynamic interaction with the wall. Rather, the particle roughness significantly changes their DLVO interaction with the wall, which in turn affects their diffusion.

A landscape classification map of Ireland and its potential use in national land use monitoring.

This study presents a novel landscape classification map of the Republic of Ireland and is the first to identify broad landscape classes by incorporating physiographic and land cover data. The landscape classification responds to commitments to identify and classify the Irish landscape as a signatory to the European Landscape Convention. The methodology applied a series of clustering iterations to determine an objective multivariate classification of physiographic landscape units and land cover datasets. The classification results determined nine statistically significant landscape classes and the development of a landscape classification map at a national scale. A statistical breakdown of land cover area and diversity of each class was interpreted, and a comparison was extended using independent descriptive variables including farmland use intensity, elevation, and dominant soil type. Each class depicts unique spatial and composition characteristics, from coastal, lowland and elevated, to distinct and dominating land cover types, further explained by the descriptive variables. The significance of individual classes and success of the classification is discussed with particular reference to the wider applicability of the map. The transferability of the methodology to other existing physiographic maps and environmental datasets to generate new landscape classifications is also considered. This novel work facilitates the development of a strategic framework to efficiently monitor, compare and analyse ecological and other land use data that is spatially representative of the distribution and extent of land cover in the Irish countryside.

Participation of Glutamatergic Ionotropic Receptors in Excitotoxicity: The Neuroprotective Role of Prolactin.

Glutamate (Glu) is known as the main excitatory neurotransmitter in the central nervous system. It can trigger a series of processes ranging from synaptic plasticity to neurophysiological regulation. To carry out its functions, Glu acts via interaction with its cognate receptors, which are ligand-dependent. Glutamatergic receptors include ionotropic and metabotropic categories. The first allows the passage of ions through the postsynaptic membrane, while the metabotropic subtype activates signaling cascades through second messengers. It is well known that an excess of extracellular Glu concentration induces overstimulation of ionotropic glutamatergic receptors (iGluRs), causing the excitotoxicity phenomenon that leads to neuronal damage and cell death. Excitotoxicity plays a crucial role in different brain pathologies such as brain strokes, epilepsy and neurodegenerative disorders. However, until now, there are no effective neuroprotective compounds to prevent or rescue neurons from excitotoxicity. Thus, the continuous elucidation of the molecular mechanisms underlying excitotoxicity in order to prevent damage or neuronal death is necessary. Therefore, the aim of this review was to summarize the current knowledge regarding iGluRs, while describing their structures and molecular mechanisms of action, including their role in excitotoxicity, as well as the current strategies to reduce excitotoxic damage. Particularly, strategies mediated by prolactin, a somatotropin family-related hormone that displays a significant neuroprotective effect against both Glu and kainic acid-induced excitotoxicity in the hippocampus, are described. Finally, the role of prolactin as a possible molecule in the treatment of excitotoxicity in neurological diseases is discussed.

Home-based exercise programmes improve physical fitness of healthy older adults: A PRISMA-compliant systematic review and meta-analysis with relevance for COVID-19.

This systematic review and meta-analysis aimed to examine the effects of home-based exercise programmes on measures of physical-fitness in healthy older adults. Seventeen randomized-controlled trials were included with a total of 1,477 participants. Results indicated small effects of home-based training on muscle strength (between-study standardised-mean-difference [SMD] = 0.30), muscle power (SMD = 0.43), muscular endurance (SMD = 0.28), and balance (SMD = 0.28). We found no statistically significant effects for single-mode strength vs. multimodal training (e.g., combined balance, strength, and flexibility exercises) on measures of muscle strength and balance. Single-mode strength training had moderate effects on muscle strength (SMD = 0.51) and balance (SMD = 0.65) while multimodal training had no statistically significant effects on muscle strength and balance. Irrespective of the training type, >3 weekly sessions produced larger effects on muscle strength (SMD = 0.45) and balance (SMD = 0.37) compared with ≤3 weekly sessions (muscle strength: SMD = 0.28; balance: SMD = 0.24). For session-duration, only ≤30 min per-session produced small effects on muscle strength (SMD = 0.35) and balance (SMD = 0.34). No statistically significant differences were observed between all independently-computed single-training factors. Home-based exercise appears effective to improve components of health- (i.e., muscle strength and muscular endurance) and skill-related (i.e., muscle power, balance) physical-fitness. Therefore, in times of restricted physical activity due to pandemics, home-based exercises constitute an alternative to counteract physical inactivity and preserve/improve the health and fitness of healthy older adults aged 65-to-83 years.

Monte Carlo Aggregation Code (MCAC) Part 2: Application to soot agglomeration, highlighting the importance of primary particles.

During the agglomeration of nanoparticles and in particular, soot, a change in both the flow regime (from free molecular to near continuum) as well as the change of agglomeration regime (from ballistic to diffusive) is expected. However, these effects are rarely taken into account in numerical simulations of particle agglomeration and yet, they are suspected to have an important impact on the agglomeration kinetics, particle morphologies, and size distributions. This work intends to study these properties by using the Monte Carlo Aggregation Code (MCAC) presented in the preceding work (part 1), focusing on the physical impacts of varying the particle volume fraction and monomers size and polydispersity. The results show an important sensitivity of the kinetics of agglomeration, coagulation homogeneity, and agglomerate morphology to the size of monomers. First, for smaller monomer diameters, the agglomeration kinetic is enhanced and agglomerates are characterized by larger fractal dimensions. Second, for large monomer diameters, fractal dimensions down to 1.67 can be found being smaller than the classical 1.78 for Diffusion Limited Cluster Agglomeration (DLCA) mechanism. One important conclusion is that variation in time of both regimes has to be considered for a more accurate simulation of the agglomerate size distribution and morphology.

Monte Carlo Aggregation Code (MCAC) Part 1: Fundamentals.

The application of Monte Carlo methods to simulate the agglomeration of suspended nanoparticles is currently limited to specific agglomeration regimes with reduced accuracy in terms of the particle's physical residence time. The definition of specific particles persistent distance, its corresponding time step and subsequent probabilities for particle displacements may improve the accuracy of this method. To solve these issues, a new persistent distance and its corresponding time step based on Langevin dynamics simulations are introduced. Additionally, a probability of particle displacements, not restricted to a specific agglomeration regime, is introduced. All the modifications are validated by comparison with Langevin dynamics simulations. Finally, the above mentioned modifications considerably improve the accuracy of Monte Carlo methods to predict the dynamics and agglomeration of suspended nanoparticles.

Comparison of ultrasound-guided transmuscular quadratus lumborum block catheter technique with surgical pre-peritoneal catheter for postoperative analgesia in abdominal surgery: a randomised controlled trial.

Following abdominal surgery, the provision of postoperative analgesia with local anaesthetic infusion through both transmuscular quadratus lumborum block and pre-peritoneal catheter have been described. This study compared these two methods of postoperative analgesia following laparotomy. Eighty-two patients 18-85 years of age scheduled to undergo elective surgery were randomly allocated to receive either transmuscular quadratus lumborum block or pre-peritoneal catheter block. In the transmuscular quadratus lumborum group, an 18-gauge Tuohy needle was passed through the quadratus lumborum muscle under ultrasound guidance to reach its anterior aspect. A 20-ml bolus of ropivacaine 0.375% was administered and catheters placed bilaterally. In the pre-peritoneal catheter group, 20 ml of ropivacaine 0.375% was infiltrated at each of three subcutaneous sub-fascial levels, and pre-peritoneal plane catheters were placed bilaterally. Both groups received an infusion of ropivacaine 0.2% at 5 ml.h-1 , continued up to 48 h along with a multimodal analgesic regime that included regular paracetamol and patient-controlled analgesia with fentanyl. The primary end-point was postoperative pain score on coughing, assessed using a numerical rating score (0-10). Secondary outcomes were pain score at rest, fentanyl usage until 48 h post-operation, satisfaction scores and costs. There was no treatment difference between the two groups for pain score on coughing (p = 0.24). In the transmuscular quadratus lumborum group, there was a reduction in numerical rating score at rest (p = 0.036) and satisfaction scores on days 1 and 30 (p = 0.004, p = 0.006, respectively), but fentanyl usage was similar. In the transmuscular quadratus lumborum group, the highest and lowest blocks observed in the recovery area were T4 and L1, respectively. The transmuscular quadratus lumborum technique cost 574.64 Australian dollars more per patient than the pre-peritoneal catheter technique.