Randomized Controlled Trial Comparing Open Simple Prostatectomy or Prostate Artery Embolization in Large Prostates: Clinical and Urodynamic Assessment - PoPAE Study.

OBJECTIVE: To evaluate the effects of Prostate artery embolization (PAE) and open simple prostatectomy (OP) on lower urinary tract symptoms and urodynamic parameters in subjects with prostate size >80cc³. METHODS: PoPAE study (OP or PAE) was a randomized, open-label controlled trial performed between January 2020 and May 2022. Subjects with large prostates (>80cc³), urodynamic parameters meeting obstruction criteria (Bladder Outlet Obstruction Index-BOOI>40), and good detrusor function (Bladder contractility index>100) were included. The primary and co-primary endpoints were the variation in peak flow rate on uroflowmetry (Qmax) and BOOI. The secondary endpoints were the IPSS and ultrasonographic changes. RESULTS: Twenty three and 25 subjects underwent PAE and OP were evaluated, respectively. At baseline, the 2 groups have shown similar clinical, radiological, laboratory, and urodynamic parameters. After 6 months, Qmax improved 8,3 ± 4.17 mL/sec in PAE and 15.1 ± 8.04 mL/sec in OP (mean difference 6.78 in favor of PE; P = .012 [CI -9.00 to -3.00]). After treatment, 88% of those men underwent OP were classified as unobstructed or equivocal (BOOi<40). On the other hand, 70% of subjects underwent PAE remained obstructed (BOOI>40) and none of them shifted to unobstructed status (BOOI<20). It was observed a similar reduction in IPSS and PVR in both groups. CONCLUSION: PAE was inferior to conventional surgery for releasing BOO and improving peak urinary flow in large prostates. Nevertheless, PAE was able to improve symptoms and PVR, and might be an alternative method in selected patients.

Parasitism of Arapaima gigas (Schinz, 1822) in fish farms of the state of Amazonas, Brazil.

The objective of this study was to investigate the parasites occurrences and to determine the rates of infestation/parasitic infection in juvenile Arapaima gigas from seven fish farms in the state of Amazonas, relating to the characteristics of these fish farms. Of the 70 A. gigas evaluated, 43 were infested/infected, with a total of 133 parasites collected. Three fish farms (2, 4, 6) showed the highest levels of prevalence of parasites (100%, 70%, 70%), mean intensity (4.1±2.6, 8.1±9.2, and 2.1±1.3), and mean abundance (4.1±2.6, 5.7±8.1, and 1.5±1.5), respectively. Prevalence ranged from 30% to 100%, mean intensity from 1.0 to 8.1 and mean abundance from 0.3 to 5.7. Monogenea, Digenea, Nematoda (Hysterothylacium sp. and Spirocamallanus sp.) and Acanthocephala (Neoechinorhynchus sp. and Polyacanthorhynchus sp.) were identified. The parasites Hysterothylacium sp. and Neoechinorhynchus sp. were the most prevalent parasites with 31.43% and 15.71%, respectively. The fish presented negative allometry in growth and constant condition factor. Measures to prevent and control the parasitic diseases diagnosed are discussed as well prophylactic practices that contribute to the biosecurity of the farms.

Conformational changes in twitchin kinase in vivo revealed by FRET imaging of freely moving C. elegans.

The force-induced unfolding and refolding of proteins is speculated to be a key mechanism in the sensing and transduction of mechanical signals in the living cell. Yet, little evidence has been gathered for its existence in vivo. Prominently, stretch-induced unfolding is postulated to be the activation mechanism of the twitchin/titin family of autoinhibited sarcomeric kinases linked to the mechanical stress response of muscle. To test the occurrence of mechanical kinase activation in living working muscle, we generated transgenic Caenorhabditis elegans expressing twitchin containing FRET moieties flanking the kinase domain and developed a quantitative technique for extracting FRET signals in freely moving C. elegans, using tracking and simultaneous imaging of animals in three channels (donor fluorescence, acceptor fluorescence, and transmitted light). Computer vision algorithms were used to extract fluorescence signals and muscle contraction states in each frame, in order to obtain fluorescence and body curvature measurements with spatial and temporal precision in vivo. The data revealed statistically significant periodic changes in FRET signals during muscle activity, consistent with a periodic change in the conformation of twitchin kinase. We conclude that stretch-unfolding of twitchin kinase occurs in the active muscle, whereby mechanical activity titrates the signaling pathway of this cytoskeletal kinase. We anticipate that the methods we have developed here could be applied to obtaining in vivo evidence for force-induced conformational changes or elastic behavior of other proteins not only in C. elegans but in other animals in which there is optical transparency (e.g., zebrafish).

Parallel Processing of Two Mechanosensory Modalities by a Single Neuron in C. elegans.

Neurons convert synaptic or sensory inputs into cellular outputs. It is not well understood how a single neuron senses, processes multiple stimuli, and generates distinct neuronal outcomes. Here, we describe the mechanism by which the C. elegans PVD neurons sense two mechanical stimuli: external touch and proprioceptive body movement. These two stimuli are detected by distinct mechanosensitive DEG/ENaC/ASIC channels, which trigger distinct cellular outputs linked to mechanonociception and proprioception. Mechanonociception depends on DEGT-1 and activates PVD's downstream command interneurons through its axon, while proprioception depends on DEL-1, UNC-8, and MEC-10 to induce local dendritic Ca2+ increase and dendritic release of a neuropeptide NLP-12. NLP-12 directly modulates neuromuscular junction activity through the cholecystokinin receptor homolog on motor axons, setting muscle tone and movement vigor. Thus, the same neuron simultaneously uses both its axon and dendrites as output apparatus to drive distinct sensorimotor outcomes.

Reverse-Correlation Analysis of the Mechanosensation Circuit and Behavior in C. elegans Reveals Temporal and Spatial Encoding.

Animals must integrate the activity of multiple mechanoreceptors to navigate complex environments. In Caenorhabditis elegans, the general roles of the mechanosensory neurons have been defined, but most studies involve end-point or single-time-point measurements, and thus lack dynamic information. Here, we formulate a set of unbiased quantitative characterizations of the mechanosensory system by using reverse correlation analysis on behavior. We use a custom tracking, selective illumination, and optogenetics platform to compare two mechanosensory systems: the gentle-touch (TRNs) and harsh-touch (PVD) circuits. This method yields characteristic linear filters that allow for the prediction of behavioral responses. The resulting filters are consistent with previous findings and further provide new insights on the dynamics and spatial encoding of the systems. Our results suggest that the tiled network of the gentle-touch neurons has better resolution for spatial encoding than the harsh-touch neurons. Additionally, linear-nonlinear models can predict behavioral responses based only on sensory neuron activity. Our results capture the overall dynamics of behavior induced by the activation of sensory neurons, providing simple transformations that quantitatively characterize these systems. Furthermore, this platform can be extended to capture the behavioral dynamics induced by any neuron or other excitable cells in the animal.

Automated screening of C. elegans neurodegeneration mutants enabled by microfluidics and image analysis algorithms.

Spinal muscular atrophy (SMA) is a degenerative disorder that selectively deteriorates motor neurons due to a deficiency of survival motor neuron protein (SMN). The illness is the leading genetic cause of death in infants and is difficult to study in complex biological systems such as humans. A simpler model system, such as the nematode C. elegans, can be used to study potential mechanisms underlying this disease; C. elegans expresses the smn-1 gene, a homologue of SMN; powerful genetic tools in C. elegans research can be used to discover novel genes whose effect on SMN remains unknown or uncharacterized. Currently, conventional screening methods are time-consuming and laborious, as well as being subjective and mostly qualitative. To address these issues, we engineer an automated system capable of performing genetic suppressor screens on C. elegans using microfluidics in combination with custom image analysis software. We demonstrate the utility of this system by isolating 21 alleles that significantly suppress motor neuron degeneration at a screening rate of approximately 300 worms per hour. Many of these mutants also have improved motor function. These isolated alleles can potentially be further studied to understand mechanisms of protection against neurodegeneration. Our system is easily adaptable, providing a means to saturate screens not only implicated in the smn-1 pathway, but also for genes involved in other neurodegenerative phenotypes.

Correction: automated and controlled mechanical stimulation and functional imaging in vivo in C. elegans.

Correction for 'Automated and controlled mechanical stimulation and functional imaging in vivo in C. elegans' by Yongmin Cho et al., Lab Chip, 2017, 17, 2609-2618.

Automated and controlled mechanical stimulation and functional imaging in vivo in C. elegans.

C. elegans is a useful genetic model system for investigating mechanisms involved in sensory behavior which are potentially relevant to human diseases. While utilities of advanced techniques such as microfluidics have accelerated some areas of C. elegans sensory biology such as chemosensation, studies of mechanosensation conventionally require immobilization by glue and manual delivery of stimuli, leading to low experimental throughput and high variability. Here we present a microfluidic platform that precisely and robustly delivers a wide range of mechanical stimuli and can also be used in conjunction with functional imaging and optical interrogation techniques. The platform is fully automated, thereby greatly enhancing the throughput and robustness of experiments. We show that the behavior of the well-known gentle and harsh touch neurons and their receptive fields can be recapitulated. Using calcium dynamics as a read-out, we demonstrate its ability to perform a drug screen in vivo. We envision that this system will be able to greatly accelerate the discovery of genes and molecules involved in mechanosensation and multimodal sensory behavior, as well as the discovery of therapeutics for related diseases.

Sazonalidade da fauna de metazoários de Pygocentrus nattereri (Kner, 1858) no lago Piranha (Amazonas, Brasil) e a avaliação de seu potencial como indicadora da saúde do ambiente / Seasonality of the metazoan fauna of Pygocentrus nattereri (Kner, 1858) in Piranha Lake, (Amazonas, Brazil), and evaluation of its potential as an indicator of environmental health

Foi estudada a fauna de metazoários parasitos de Pygocentrus nattereri capturadas no lago Piranha, durante as fases do ciclo hidrológico do ano de 2007. Foi verificada a relação entre o fator de condição e a ocorrência de parasitos, e também a viabilidade da utilização da fauna parasitária de P. nattereri como bioindicadora da saúde do ambiente. Foram coletados monogenóideos das espécies Amphithecium microphalum, Amphitecium brachycirrum, Amphitecium calycinum, Amphithecium catalaoensis, Amphithecium junki, Pithanothecium amazonensis e Rhinoxenus piranhus, o nematóide Procamallanus inopinatus, copépodos da espécie Miracetyma sp. e o isópoda Anphira branchialis. Não houve correlação significativa entre a ocorrência dos parasitos com o fator de condição dos peixes. Houve variações significativas entre os índices parasitários nos diferentes períodos do ciclo hidrológico e P. nattereri satisfez os requisitos descritos na literatura para selecionar um peixe hospedeiro e sua parasitofauna como bioindicadora.

The metazoan parasitic fauna of Pygocentrus nattereri collected in different phases of hydrologic cycle of Piranha lake was studied during the year of 2007. The study area is located in gas pipeline Coari-Manaus construction zone, near the municipality of Manacapuru-Am. The relationship between condition factor and parasite occurrence and the viability of use the parasitic fauna as an environmental bio-indicator were verified. The following Monogenoidea were collected: Amphithecium microphalum, Amphitecium brachycirrum, Amphitecium calycinum, Amphithecium catalaoensis, Amphithecium junki, Pithanothecium amazonensis e Rhinoxenus piranhus, as well as the nematode Procamallanus inopinatus, the copepod Miracetyma sp. and the isopod Anphira branchialis. There was not significant correlation between the parasite occurrence and the condition factor. There were significant variances in the parasitic index according to the different periods of hydrologic cycle and P. nattereri has achieved the conditions described in the literature to be select a fish-host and his parasite fauna as biomonitor.