Effects prenatal exposure to peat smoke on the emotional behavior of rat offspring and its correction with fabomotizole

Relevance. Long-term smoke from forest fires cause a wide range of health disorders, including somatic state, emotional status, and cognitive functions. The question of the consequences of exposure to combustion products of peat and wood during pregnancy for offspring remains open. Intention. The goal is to explore the disorders (anxiety, reflex behavior, aggression, etc.) that occur in the offspring of rats exposed to peat smoke in the early and late postnatal periods and the effect of fabomotizole on these disorders. Methodology. The research was conducted on the offspring of rats of both sexes from females forcibly exposed to peat smoke (1-20 days). The effect of peat smoke on rats and the protective effect of fabomotizole (1 and 10 mg / kg / 20 days of gestation) were studied in the early (5 days) and late (60-80 days) postnatal periods. The formation of the sensory-motor reflex, anxiety, aggression, and motor activity were assessed. Results and discussion. Exposure to peat smoke of pregnant females (from 1-20 days of gestation) causes a perturb in the formation of a sensory-motor reflex in the early postnatal period ( 5 days), a decrease in the level of natural adaptive reactions and intraspecific aggression, as well as an increase in locomotor activity in mature animals (60-80 days). Fabomotizole, when administered prenatally (1-20 days of gestation) at doses of 1 and 10 mg / kg, corrected the formation of a conditioned sensory-motor reflex in male and female rat pups, data of the emotional status and motor activity of sexually mature animals. Conclusion. The protective effect of fabomotizole on the offspring of rats prenatally exposed to peat smoke from the toxic effects of peat combustion products was revealed. Fabomotizole returns the studied behavioral reactions, disturbed by peat, to the level of the physiological norm, which confirms the previously established cyto- and neuroprotective properties of the drug.

The neurobiology of splitbrain crayfish

Background: They crayfish brain is segmented into two symmetrical hemiganglia. Normally both hemiganglia are in direct communication through a series of well-defined neural bridges that cross de midline to form reciprocal cross connections.Methods: An original study was carried out in the Department of Physiology of the Faculty of Medicine, UNAM during the period from August 2019 to August 2020. 13 Crayfish Procambarus clarkii weighing between 1g to 30g were used. Each eyestalk of the animals was tied to a displacement transducer coupled with a polygraph so that optomotor or electrical activity was bilaterally recorded. The separation of the right from the left hemiganglia from the cerebral or supraesophageal ganglion was performed with a sagittal section, splitbrain (SB).Results: The normal photo motor reflex in crayfish eye is measured as a gradual decrease in the ERG amplitude. During tactile stimulation, the visual activation of both eyestalks in normal crayfish leads to a highly regular bilateral activity. The regular activity can only be altered by disturbing the mechanoreceptors located in the shell surrounding the eyestalks.Conclusions: The procedure presented in this article provides unique characteristics for the study of the nervous system such as a detailed response of the bilateral optomotor reflex.

Elementary nervous systems

The evolutionary origin of the nervous system has been a matter of long-standing debate. This is due to the different perspectives taken. Earlier studies addressed nervous system origins at the cellular level. They focused on the selective advantage of the first neuron in its local context, and considered vertical sensory-motor reflex arcs the first nervous system. Later studies emphasized the value of the nervous system at the tissue level. Rather than acting locally, early neurons were seen as part of an elementary nerve net that enabled the horizontal coordination of tissue movements. Opinions have also differed on the nature of effector cells. While most authors have favoured contractile systems, others see the key output of the incipient nervous system in the coordination of motile cilia, or the secretion of antimicrobial peptides. I will discuss these divergent views and explore how they can be validated by molecular and single-cell data. From this survey, possible consensus emerges: (i) the first manifestation of the nervous system likely was a nerve net, whereas specialized local circuits evolved later; (ii) different nerve nets may have evolved for the coordination of contractile or cilia-driven movements; (iii) all evolving nerve nets facilitated new forms of animal behaviour with increasing body size. This article is part of the theme issue ‘Basal cognition: multicellularity, neurons and the cognitive lens’.

Elovl2 Is Required for Robust Visual Function in Zebrafish

Omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) play critical roles in membrane stability and cell signaling within the retina. ELOVL2 (Elongation of Very Long Chain Fatty Acids-Like 2), an elongase involved in the synthesis of long chain polyunsaturated fatty acids (LC-PUFAs), has recently been implicated in regulating aging in the mammalian retina. In this work, we characterize the expression and function of elovl2 in the retina development in embryonic zebrafish. Whole mount in situ hybridization shows elovl2 is expressed in the Muller glia in embryonic and adult zebrafish. Lipidomics analysis of elovl2 crispants whole embryos at day 2 and eyes at day 7 demonstrated significant changes in lipids composition, especially on the level of lipids containing docosahexaenoic acid (DHA). Histological analysis of zebrafish lacking elovl2 revealed increased retinal thickness compared to controls at day 7 without gross disruptions of the retinal architecture. Finally, elovl2 crispants showed differences in the visual motor reflex light off (VMR-OFF) at day 7 compared to controls. In sum, inactivation of elovl2 in zebrafish embryos caused changes in lipid composition and in visual behavior, further confirming the important role of LC-PUFAs in healthy vision.

Bloqueio anestésico do plexo braquial em sagui-de-tufos-brancos (Callithrix jacchus Linnaeus, 1758) - Relato de caso

<span style="left: 118.11px; top: 959.809px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.664313);">The use of anesthetic block of the brachial plexus is a technique used to desensitize the thoracic limb,which </span><span style="left: 118.11px; top: 981.809px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.686042);">is performed in several species, including primates. The objective of this work is to evaluate or block the </span><span style="left: 118.11px; top: 1003.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.705156);">brachial plexus with a supraclavicular technique, a response to the mechanism in a motor and sensory </span><span style="left: 118.11px; top: 1025.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.704964);">manner, and the duration of time in a white-tufted marmoset (Callithrix jacchus). The animal was an adult male, </span><span style="left: 118.11px; top: 1047.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.671396);">weighing 340 grams and had a humerus fracture of the right thoracic limb , diagnosed through clinical and </span><span style="left: 118.11px; top: 1069.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.717934);">radiographic evaluation. After being taken for surgery, the animal was previously medicated with 0.04 mg / kg </span><span style="left: 118.11px; top: 1091.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.705268);">dexmedetomidine and ketamine 10 mg / kg, both intramuscularly in the same syringe and, after that we did the </span><span style="left: 118.11px; top: 1113.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.713891);">Anesthetic block of the brachial plexus using the supraclavicular technique with 5mg / kg lidocaine. Heart rate, </span><span style="left: 118.11px; top: 1135.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.723765);">respiratory rate, body temperature and temperature improvement were evaluated throughout the procedure. </span><span style="left: 118.11px; top: 1157.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.72968);">Although the technique has been used in studies with other primate species, the block was effective and the </span><span style="left: 118.11px; top: 1179.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.721086);">animal’s motor reflex was sensitive after 46 minutes, while the tactile sensory perception was gained after 60 </span><span style="left: 118.11px; top: 1201.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.711203);">minutes . The use of the technique was effective in the species and the monitoring of the patient was crucial to </span><span style="left: 118.11px; top: 1223.81px; font-size: 18.6162px; font-family: sans-serif; transform: scaleX(0.716029);">increase the success of anesthesia and the comfort of the animal throughout the procedure.</span>

ELOVL2 is required for robust visual function in zebrafish

ABSTRACTOmega-3 and omega-6 polyunsaturated fatty acids (PUFAs) play critical roles in membrane stability and cell signaling within the retina. Elovl2, an elongase involved in synthesis of long chain polyunsaturated fatty acids (LC-PUFAs), has recently been implicated in regulating aging in the mammalian retina. In this work, we characterize the expression and function of elovl2 in retina development in embryonic zebrafish. Whole mount in situ hybridization shows elovl2 is expressed in the Müller glia in embryonic and adult zebrafish. Lipidomics analysis of elovl2 crispants whole embryos at day 2 and eyes at day 7 demonstrated significant changes in lipids composition, especially on the level of lipids containing docosahexaenoic acid (DHA). Histological analysis of zebrafish lacking elovl2 revealed increased retinal thickness compared to controls at day 7 without gross disruptions of retinal architecture. Finally, elovl2 crispants showed differences in the visual motor reflex light off (VMR-OFF) at day 7 compared to controls. In sum, inactivation of elovl2 in zebrafish embryos caused changes in lipid composition and in visual behavior further confirming the important role of LC-PUFAs in healthy vision.

Hydrovibrotactile stimulation in rehabilitation of deaf children

Goals of the study were investigation the perception of vibro-acoustic signals, spreading in water, by deaf patients and the possibility of use hydrovibrotactile stimulation for habilitation of deaf children. In the first part of study 5 experienced cochlear implants (CI) users were involved – 2 adults and 3 children with congenital deafness. Participants were presented modulated tones (100-4000 Hz) and natural sounds (horn, pipe, march melody) though underwater loudspeakers in small swimming pool. Each participant was sitting in the swimming pool without CI during the stimulation. It was shown that deaf subjects are able to detect vibro-acoustic signals, spreading in water, which they feel as a vibrotactile sense. The most vibrotactile sensitivity was between 100 and 400 Hz, while stimuli between 1000 Hz and 4000 Hz didn’t evoke any sensation. In the second part of the study 30 early aged children with severe or profound sensorineural hearing loss without hearing aids or CI experience were participated. It was observed typical oriented behavioral reactions in response to test stimuli in water in 15 children from the experimental group, but there weren’t reactions to the acoustic component of stimuli on air (out of water). Hydrovibrotactile stimulation sessions prior amplification and CI processor fitting accelerated the development of oriented and stable condition motor reflex reactions to sounds in children with hearing aids and CI, including even near-threshold stimuli, in comparison with control group children, who got only traditional lessons with speech-language therapist. As a result, an adequate fitting of hearing aids or CI processor and spontaneous development of hearing behavior in everyday situations were achieved significantly faster.

Grasping adjustments to haptic, visual, and visuo-haptic object perturbations are contingent on the sensory modality

Haptics provides information about the size and position of a handheld object. However, it is still unknown how haptics contributes to action correction if a sudden perturbation causes a change in the configuration of the handheld object. In this study, we have occasionally perturbed the size of an object that was the target of a right-hand reach-to-grasp movement. In some cases, participants were holding the target object with their left hand, which provided haptic information about the object perturbation. We compared the corrective responses to perturbations in three different sensory conditions: visual (participants had full vision of the object, but haptic information from the left hand was prevented), haptic (object size was sensed by the left hand and vision was prevented), and visuo-haptic (both visual and haptic information were available throughout the movement). We found that haptic inputs evoked faster contralateral corrections than visual inputs, although actions in haptic and visual conditions were similar in movement duration. Strikingly, the corrective responses in the visuo-haptic condition were as fast as those found in the haptic condition, a result that is contrary to that predicted by simple summation of unisensory signals. These results suggest the existence of a haptomotor reflex that can trigger automatic and efficient grasping corrections of the contralateral hand that are faster than those initiated by the well-known visuomotor reflex and the tactile-motor reflex. NEW & NOTEWORTHY We show that online grip aperture corrections during grasping actions are contingent on the sensory modality used to detect the object perturbation. We found that sensing perturbations with the contralateral hand only (haptics) leads to faster action corrections than when object perturbations are only visually sensed. Moreover, corrections following visuo-haptic perturbations were as fast as those to haptic perturbations. Thus a haptomotor reflex triggers faster automatic responses than the visuomotor reflex.

Clinician-rated measures for distal symmetrical axonal polyneuropathy

Distal symmetrical axonal polyneuropathy (DSP) is due to injury to peripheral sensory, motor, and autonomic nerve fibers, resulting in distal predominant sensory loss, pain, and gait instability. DSP occurs as a complication of multiple medical conditions including diabetes or HIV, or following exposure to various toxins such as chemotherapy. It affects at least 10% of the United States population. Few treatments for DSP are approved by regulatory agencies. Reliable and responsive outcome measures are integral to developing new DSP treatments. Multiple clinician-rated measures that incorporate neuropathy signs exist, however, it is not clear which of these measures performs best for various DSP phenotypes. This systematic review summarizes the content of 18 published measures of DSP identified using PubMed and from personal archives of the authors. The relative percentage of scoring dedicated to motor, reflex, large and small fiber sensory, and autonomic domains varied considerably among measures. The most common neurologic examination items included in the scales were (1) vibration perception (n = 18, 100%), (2) reflexes (n = 16, 89%), (3) pinprick perception (n = 14, 78%), (4) muscle strength (n = 11, 61%), (5) touch–pressure perception (n = 9, 50%), and (6) joint position perception (n = 8, 44%). This review can be used to inform decisions regarding which of the available clinician-rated sign outcome measures would be most appropriate for use in a particular DSP population, based on the domains most affected by that neuropathy or on the domains most likely to be affected by a particular experimental therapy.