The low back is the weight-bearing part of the human trunk and has a complex anatomy with a variety of lesions. The traditional diagnostic imaging methods include X-ray, CT, and magnetic resonance imaging (MRI). With the rapid development of ultrasound diagnostic instruments and diagnostic techniques, high-frequency ultrasonography plays a more important role in the diagnosis of musculoskeletal disorders by virtue of its advantages of being safe, noninvasive, inexpensive, repeatable in a short period of time, and real-time imaging, especially for the display of fine structures of soft tissues, which is superior to CT and MRI. In this paper, the puncture needle was punctured near the intervertebral foramen, anti-inflammatory analgesics were injected under ultrasound surveillance. The anti-inflammatory and analgesic drugs mainly consist of local anesthetics and glucocorticoids. Local anesthetics can immediately block the nociceptive transmission of the diseased nerve, improve muscle tension, and eliminate muscle spasm, and glucocorticoids can effectively eliminate edema and inflammation of the lumbar nerve root and its surrounding tissues. The results showed that high-frequency ultrasound, as a noninvasive imaging examination, can clearly display the structure and spatial hierarchy of the skin, superficial fascia, deep fascia, and muscles of the low back, can provide real-time dynamic bilateral contrast observation, which can be the preferred imaging examination method for soft tissue disorders of the low back, and can compensate with general X-ray, CT, and magnetic resonance imaging to provide richer clinical diagnosis and treatment. It can provide richer imaging information for clinical diagnosis and treatment. Clinicians usually use X-rays, CT, and magnetic resonance imaging (MRI) to examine musculoskeletal disorders. Because X-rays are not effective in examining soft tissues, CT only shows static images and is nonfunctional, lacking detailed information on soft tissue lesions; MRI can be used to examine joints and soft tissues, but it is expensive, takes a long time, and has some contraindications, so it is not yet a routine examination. High-frequency ultrasound has the advantages of no radiation damage, noninvasive, inexpensive, repeatable within a short period of time, real-time imaging, high resolution, and so on and is widely used. It has been proved that high-frequency ultrasound can clearly display the hierarchical relationship and internal structure of muscles and other soft tissues, identify tissue lesions of joints, muscles, tendons, and ligaments, and also observe the relationship between lesions and surrounding tissues from any direction and angle to obtain all-round information of lesions . High-frThe low back is the bridge between the human trunk and the lower extremities. Military training, physical exercise, physical labor, and sudden violence can easily lead to various acute and chronic injuries to the muscles of the low back. Active and violent contraction or passive overstretching of the muscles of the low back can cause acute lacerations, that is, muscle strains, and can involve myofascia, tendons, ligaments, and other soft tissues. High-frequency ultrasonography can make an accurate assessment of the site, extent, and degree of muscle injury. Previous authors  used higUltrasound-guided nerve block techniques have been widely used and developed in pain management and clinical anesthesia over the past decade or so. Clinicians first use ultrasound to scan peripheral nerves and their surrounding structures to detect or rule out abnormalities and then perform safe and accurate puncture and drug injection for the target nerve under dynamic real-time ultrasound guidance. Real-time ultrasound guidance avoids puncture damage to blood vessels, internal organs, and other critical tissue structures, greatly reduces treatment complications, and improves effectiveness. As a noninvasive imaging test, high frequency ultrasound can be used as the first choice of skin, superficial fascia, deep fascia and muscle structure and lumbar spatial hierarchy, and hip soft tissue disorders and can compensate for general X-ray, CT, and MRI and provide more extensive image information for clinical diagnosis and treatment. At present, there is little research on ultrasound anatomy of the low back in China, and there is a lack of unified operation standard. It is believed that with the continuous improvement of high-end ultrasound diagnostic instruments and new diagnostic techniques, high-frequency ultrasonography will play a pivotal role in the diagnosis and prognosis assessment of low back diseases. In this paper, the puncture needle was punctured near the intervertebral foramen and next to the lumbar nerve root under ultrasound dynamic real-time guidance, and anti-inflammatory analgesics were injected under ultrasound surveillance. The anti-inflammatory and analgesic drugs mainly consist of local anesthetics and glucocorticoids. Local anesthetics can immediately block the nociceptive transmission of the diseased nerve, improve muscle tension, and eliminate muscle spasm, and glucocorticoids can effectively eliminate edema and inflammation of the lumbar nerve root and its surrounding tissues.P > 0.05) when compared with the control group in terms of age, height, weight, and BMI, and the results are shown in A total of 101 cases with complete data on muscle injury and 80 cases without muscle injury were included in this study. The subject group was 20–39 years old, with a mean age of (29.6 ± 4.1) years, a mean height of (162.43 ± 4.99) cm, a mean preinjury weight of (57.58 ± 8.97) kg, and a mean preinjury BMI . The differences were not statistically significant , strengthening test (+), and jerk test (+) on the affected side. ③ CT or MRI of the intervertebral disc confirms lumbar disc protrusion: the size of the protrusion does not exceed 1/3 of the spinal canal, and the protrusion is not significantly calcified. ④ Physiotherapy and conservative treatment were ineffective after 1 month. ⑤ A frontal and lateral view of the lumbar spine in a standing position and a pelvic plain film were taken. The symptomatic areas can be shown in χ2 test; the measurement data of normal distribution were expressed as x ± s, in which the t-test was used for the paired control group within the group and the t-test for two independent samples between the groups, and the measurement data of nonnormal distribution were tested by rank sum test, and the difference was considered statistically significant at P > 0.05.The data were statistically processed using SPSS22.0 software, and the count data were expressed as rate by P < 0.05) in the change in treatment pain score (VAS score) and Oswestry dysfunction index between the study group (Group A) and the control group (Group B). This indicates that ultrasound-guided lumbar nerve root block combined with American chiropractic treatment has a higher accuracy rate and better efficacy and can be effectively used for the treatment of low back pain due to lumbar muscle injury. In summary, ultrasound-guided lumbar nerve root block combined with American chiropractic treatment for lumbar muscle injury has the advantages of simple operation, high patient satisfaction, and safety and effectiveness when applied clinically. The combination of ultrasound-guided lumbar nerve root block and American chiropractic treatment for lumbar muscle injuries has high application value in clinical promotion [In the treatment of lumbar muscle injury with ultrasound-guided lumbar nerve root block, the core factor that ultimately determines the treatment effect is whether the puncture needle can safely and accurately reach the external orifice of the intervertebral foramen, where the nerve root penetrates the spinal canal. However, due to the deformity or trauma of the lumbar spine , the traromotion –25.First of all, a series of syndromes related to lumbar spinal pain caused by the irritation or compression of lumbar nerve roots, spinal cord, or cauda equina nerve due to degeneration of lumbar disc, rupture of fibrous ring, and herniated nucleus pulposus are known as lumbar muscle injury. Lumbar muscle injury is very common in clinical orthopedics, pain medicine, rehabilitation, and acupuncture and is also the most common cause of lumbar pain. The main reason is that modern young and middle-aged people have more ambulatory workers, generally lack of scientific and adequate physical exercise; sedentary lifestyle can accelerate the degenerative changes of the lumbar intervertebral discs, and the human waist structure needs to bear the weight of the upper body, but also to bear the mechanical conduction of the buffer, the combination of the above factors lumbar muscle injury belongs to a disease of the times that urgently needs to be solved. The causes of intervertebral disc degeneration are divided into many kinds; nowadays the society is highly developed electronic products, most people are sedentary leading to lumbar muscle strain, and the improper posture of people's work life and lack of exercise is also another important cause of lumbar disc degeneration.Over the years, the pace of modern urban life is getting faster and faster, the pressure of life is gradually increasing, and people's lifestyles have also undergone a radical change, but modern people lack the concept and awareness of health care in general and does not love exercise; most people have developed the bad habit of sitting for a long time; sedentary lifestyle can lead to the muscles being in a state of tension for a long time. In the case of imbalance, the strength of the waist muscles will increase over time. The lumbar muscles are the most important structure to play a supporting role in addition to the lumbar vertebrae. Once the lumbar muscles declined in function can not well maintain the physiological curvature of the lumbar spine, the lumbar spine physiological curvature changes after the lumbar spine anatomy and histology will be followed by pathological changes; these results are often incorrect and overuse and are often caused by incorrect and excessive use of the lumbar spine.The fibrous annulus of the already fragile lumbar intervertebral disc in humans is very vulnerable to destruction, which leads to the protrusion of the nucleus pulposus through the fibrous annulus and subsequent compression and stimulation of the nerve roots, spinal cord, cauda equina, and other tissue structures, eventually leading to local sterile inflammation and impaired blood circulation, which can also cause lumbar nerve edema and other corresponding clinical symptoms. The core of this study is how to eliminate the entrapment of lumbar nerve roots, spinal cord, and cauda equina nerve, eliminate edema and sterile inflammation of nerve roots, and repair the injured nerve roots and adjacent soft tissues, as shown in In conclusion, this study evaluated ultrasound-guided lumbar nerve root block combined with American chiropractic for the treatment of lumbar muscle injuries. American chiropractic manipulation is easy, effective, inexpensive, and less risky, so it is used as one of the first treatments for nonsurgical treatment of lumbar muscle injuries in the United States and other countries. The anti-inflammatory and analgesic solution required for lumbar nerve root block treatment consists of Depo-Provera and local anesthetics, of which Depo-Provera can play a strong anti-inflammatory role, and local anesthetics can provide immediate pain relief and block pain transmission, while ultrasound guidance ensures that the puncture needle can quickly and safely reach the external orifice of the intervertebral foramen to inject the anti-inflammatory and analgesic mixture through the intervertebral foramen to reach the disease and rapidly control the symptoms, as shown in Conservative treatment is often ineffective, and many patients come to the clinic because they are unwilling to undergo open surgery. Minimally invasive interventions and manual therapy are often easily accepted by patients. Minimally invasive treatment methods have developed rapidly in recent years, mainly because of the rapid development of imaging; clear visualization of medical treatment makes minimally invasive technology grow a pair of “perspective eyes” because ultrasound scanning does not produce any radiation and adverse effects on the doctor and the patient and can guide the doctor to adjust the puncture needle in real time and other characteristics. The ultrasound scan has become a hot topic among the many guidance methods for the treatment of lumbar muscle injuries. Nerve block treatment can quickly stop pain and target nerve roots for rapid anti-inflammation and swelling, which achieves efficient and safe treatment purpose. Therefore, ultrasound-guided lumbar nerve root block treatment has become one of the treatment modalities frequently adopted by pain departments, orthopedic departments, rehabilitation departments, and other related departments at home and abroad.American chiropractic has low requirements for the treatment environment and treatment equipment, and any doctor with formal training can operate this method to treat spinal disorders such as lumbar muscle injuries. American chiropractic quickly corrects subluxated vertebrae through noninvasive and convenient treatment, immediately relieves nerve root entrapment symptoms, solves the real problem of uneven disc pressure, prevents further subluxation of vertebrae, and has better long-term efficacy. The long-term results are good, as shown in Lumbar muscle injury is one of the main causes of lumbar pain in clinical practice, and conservative treatments such as braking, drugs, and physiotherapy are the most common treatments for it. Most of the patients whose conservative treatments are ineffective in clinical practice can get improvement through nerve block treatment and Chinese orthopedic massage, but some patients with persistent lumbar muscle injury still do not improve after the above treatments, and the number of recurrences is frequent, or the treatment. The effect does not last long, and there are certain patients who have gastrointestinal reactions, local skin muscle damage, and other changes due to receiving prolonged medication and physical therapy, which instead aggravate the injury and pain, and some patients even lose their labor force as a result. In this study, we observed the efficacy of lumbar muscle injury by precisely blocking the lumbar nerve roots combined with American chiropractic under ultrasound guidance, and through clinical research, we concluded that ultrasound-guided puncture needles reach the nerve roots, while anti-inflammatory and analgesic solution can be precisely injected into the diseased nerve roots under ultrasound guidance to improve patients' lumbar and lower limb dysfunction. Nerve root block therapy mainly exerts its clinical effects through safe doses and concentrations of glucocorticoids and is currently used mainly for bone and joint, nerve, and soft tissue treatment. Lidocaine blocks nerve excitation and conduction by inhibiting nerve cell sodium channels. Related studies have shown that this approach has become a safe and effective therapy for aseptic inflammation.However, the long-term effect of this method of treatment is not ideal, because it does not change the main cause of disc rupture but is only “symptomatic treatment,” so the effect is short, but American chiropractic treatment complements this defect, and it uses a quick and safe way to resolve vertebral subluxation and ossify the diseased vertebra. The long-term efficacy is addressed by stabilizing the diseased vertebrae in a state of pressure balance for a longer period of time. Few studies combining the two techniques have been reported, so we collected such patients for combined treatment and observed their long-term and short-term outcomes. It was found that the combination of the two techniques had a “complementary” effect, so “ultrasound-guided lumbar nerve root block combined with American chiropractic for lumbar muscle injuries” may be a more effective method for lumbar muscle injuries. The combination of ultrasound-guided lumbar nerve root block and American chiropractic treatment for lumbar muscle injuries can provide satisfactory results in both immediate and long-term outcomes. Minimally invasive or interventional treatment is the core technology of pain management, so if pain physicians can combine their core technology with American chiropractic treatment for clinical application, there will be great application prospects and socioeconomic benefits.Lumbar muscle injury is a series of clinical symptoms mainly caused by lumbar pain and cauda equina dysfunction due to the rupture of the fibrous ring and protrusion of the nucleus pulposus as a result of external forces or unbalanced forces on the basis of degenerative changes in the lumbar disc, mechanical compression of the adjacent nerve roots and spinal cord by the fibrous ring and/or nucleus pulposus, and stimulation of the nerves and surrounding soft tissues by inflammatory factors released from the nucleus pulposus. In recent years, electronic products are widely used, and sedentary workers are becoming more and more common, which leads to tension, weakness, spasm, force imbalance, and even atrophy of lumbar muscles and ligaments, which cannot protect the lumbar vertebrae and ancillary structures well, so the incidence of lumbar muscle injury has gradually increased in recent years, as shown in Patients with low back pain in the acute phase need at least half a month of bed rest, during which time the doctor will generally prohibit the patient from most of the exercises; sufficient scientific bed rest can make the injured muscles and ligaments get more adequate rest and repair, and the squeezed and strained muscles and ligaments can get very good relief, at the same time, bed rest can also help patients improve the lumbar spine. For these reasons, bed rest can not only improve the compression and stimulation of the lumbar nerve roots, spinal cord, and cauda equina, but also promote blood circulation in the lumbar region and eliminate sterile inflammation of the lumbar nerves, muscles, and ligaments. In taking bed rest for treatment, different patients should be different in the choice of mattress; generally speaking, fat patients can choose relatively hard mattress, relatively thin patients can choose relatively soft mattress, and moderate weight patients choose moderate hardness of the mattress, and for those who absolutely can not be generalized, all choose harder mattress, because hard mattress will be easier to damage thin patients stress contact parts of the soft tissue, is not conducive to improving the curvature of the patient's lumbar spine, and is not conducive to the repair of soft tissue in the lumbar region. This is mainly because of the following. (1) The clinical receiving physician was inexperienced and did not take into account the lumbar muscle rupture, and the examination request form only requested to examine the triceps calf injury. (2) Poor examination technique of the ultrasonographer resulted in the acoustic beam not being perpendicular to the lumbar muscles and affected by anisotropic artifacts, leading to missed diagnosis and misdiagnosis. (3) The lumbar muscle rupture occurred proximally, not in the good area of 2–6 cm on the heel bone, and the examining physician was inexperienced and did not move proximally until the muscle moved to the tendon as a result of continuous dynamic examination, as shown in High-frequency ultrasound is widely used for musculoskeletal system examination in recent years because of its high-frequency and high spatial resolution. The lumbar muscles are close to the subcutaneous layer of the heel skin and are superficially located, so high-frequency ultrasound can clearly show the lumbar muscles and peritendinous tissues, and MRI is the best way to examine soft tissue lesions. The area 2–6 cm above the heel stop of the lumbar muscles has the worst blood supply and is the most frequent site of lumbar muscle rupture, accounting for 72%–73% of lumbar muscle ruptures. Acute lumbar muscle rupture is mostly caused by trauma and is most common in sports enthusiasts, with typical symptoms and signs: sudden heel “stick sensation” during exercise, followed by pain, progressive swelling, limited plantar flexion of the ankle joint, and increased pain when walking . Acute lumbar muscle rupture has typical ultrasound findings: disruption of lumbar muscle continuity, visible severed ends, hypoechoic filling between the severed ends, and retraction of the severed ends. High-frequency ultrasound has a diagnostic accuracy of 80% to 90% for acute lumbar muscle rupture, as shown in x2 = 1.908, P=0.167); the diagnostic compliance rate of ultrasound for partial rupture of obsolete lumbar muscles was significantly lower than that of MRI and the difference was statistically significant , which is consistent with the results of previous studies. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of ultrasound and MRI in the diagnosis of old lumbar muscle rupture in this study were 81.1%, 65.0%, 86.0%, 56.5%, and 76.7% and 96.2%, 95.0%, 98.1%, 90.5%, and 95.7%, respectively, indicating that the diagnostic value of ultrasound for old lumbar muscle rupture was lower than that of MRI, and the difference was statistically significant (P < 0.05).In this study, the diagnostic compliance rates of ultrasound and MRI for old lumbar muscle rupture were 81.1% and 96.2%, respectively, which were generally consistent with the data reported in the literature. The diagnostic accuracy of high-frequency ultrasound and MRI for complete and partial rupture of obsolete Achilles tendon in this study was 90.9% and 33.3% versus 97.7% and 88.9%, respectively. It can be seen that the difference between ultrasound and MRI for the diagnosis of complete rupture of obsolete lumbar muscles was not significant and the difference was not statistically significant (


Concussion in sports has received a great deal of media attention and may result in short and longer-lasting symptoms, especially in adolescents. Although significant strides have been made in the identification and management of concussion, less is known about the primary prevention of this condition. The aims of this scoping review are to (1) summarize the current research of physical conditioning strategies to reduce or prevent concussion incidence in individuals participating in sport, especially adolescents, and (2) to identify gaps in the knowledge base. Our research question was what is known from the existing literature about physical preparation strategies to reduce or prevent concussion in adult and adolescent sports?WorldCat.org; Mendeley; EBSCOHost and Ovid MEDLINE). To increase the search range, subject experts were consulted and articles and reference lists were hand searched. A scoping review methodology identified eligible studies that analyzed physical preparation techniques on modifiable physical risk factors in athletes to reduce the incidence of concussion. The PRISMA-ScR checklist guided the reporting of the findings.Three literature searches were conducted by information officers at two universities at six-month intervals, using five electronic databases (PubMed; A total of 1414 possible articles were identified, after duplicates removed, and articles analyzed against the inclusion and exclusion criteria, only 9 articles qualified for analysis. Two articles were found from studying reference lists. Thus, a total of 11 articles were included in the final evaluation for the purposes of this study. Data are reported from mostly adolescent subjects participating in nine different sports from three countries. Findings are presented with specific reference to previously recognized modifiable risk factors of concussion which include neck strength, neck size, cervical stiffness, type of sport, and pre-activity exercises.There is limited research examining the physical preparation of athletes, especially in adolescents, to reduce or prevent concussion, and conflicting evidence in the few small sample studies that were identified. This scoping review identifies the research gap for a potentially vital modifiable risk factor, notably in the physical preparation of children and adolescents to reduce or prevent sports-related concussion.The online version contains supplementary material available at 10.1186/s40798-021-00312-y. Physical conditioning strategies may have beneficial effects on some modifiable risk factors for sustaining a sport-related concussion, although existing evidence is limited and conflicting.It is unclear which modes or dosage of physical conditioning strategies reduce the incidence or effects of sport-related concussion.Future studies to specifically assess the effects of both proprioceptive and dynamic strengthening of the neck musculature to reduce forces transmitted to the brain are recommended.Sport-related concussion (SRC) has a high incidence affecting approximately four million people in the USA every year, mainly persons aged 7 to 19 years , with poTrauma to the brain can result from direct and indirect contact events. Player-to-player contact  is the most common scenario that results in concussion in many sports , 15, 16,The ability to minimize or modify identified risk factors may reduce the effect or incidence of concussions in children. Previously identified risk factors for concussion include: a history of concussions, level of education, age, level of competition, behavior, sex, unanticipated contact, neck stiffness, predisposing psychological factors, neck strength, and neck girth , 27–32. Physical preparation exercises have proven successful in reducing the effects of less common and less serious injuries –42 and rIdentifying the research questionIdentifying relevant studiesStudy selectionCharting the dataCollating, summarizing and reporting the resultsOptional consultation.The methodological framework to identify literature for the current scoping review was developed by Arksey and O’Malley , 46. ThiFinally, for reporting guidance of the results, the PRISMA-ScR checklist was used .what is known from the existing literature about physical preparation strategies to reduce or prevent concussion in adult and adolescent sports? The wide approach to this review was maintained to generate a breadth of coverage.The research question for this scoping review was To comprehensively identify applicable search results of this scoping review, a three-round strategy involved searching for research evidence via different sources, including electronic databases, reference lists, and hand-searching journals Fig. .Fig. 1PWorldCat.org and Mendeley) used the keywords and combinations of keywords as described in Additional file WorldCat.org, EBSCOHost and Ovid MEDLINE Databases using keywords as described in Additional file The first electronic search was conducted on 9 September 2019 using keywords selected by the author team assisted by an Information Officer from University of KwaZulu Natal (UKZN) who guided the search strategy. The search strategy of UKZN’s electronic databases , year of data collection, study location, sportIntervention type, and comparator (if any); duration of the interventionStudy populations Aims of the studyMethodologyOutcome measuresImportant resultsThe data were interpreted by sorting material according to key issues and themes using Microsoft Excel. Together, these data formed the basis of the analysis. The information was recorded as follows:The results of this search were summarized and combined in the data extraction table Table . The autThe 11 articles included in this review comprised of studies conducted only in the Northern Hemisphere, 8 in North America, 1 in Germany, and 2 in the UK , 48–55. With regard to sports codes discussed in the selected articles , 48–55, Mansell et al. (2005)  reportedSchmidt et al. (2014) reported on the incidence and nature of head impact biomechanics using the Head Impact Telemetry System in a small sample of American Football players who completed preseason cervical testing of isometric neck strength, electromyography, muscle size, and response to cervical perturbation . The repLisman et al. (2012) examined the effects of an 8-week isoinertial cervical resistance training program and the electromyographic (EMG) activity of neck muscles and the kinematics of the head and neck in response to a American Football tackle . The resPLin) or peak rotational acceleration (PRot) for the anterior neck flexors , anterolateral neck flexors , cervical rotators , posterolateral neck extensors , or upper trapezius . The authors concluded that the findings of this study do not support that cervical muscle strength is a factor in modifying head impact severity . The second study reported on multiple contact sports with a large sample of male and female participants and concluded that a smaller average neck circumference and smaller average neck to head circumference ratio were significantly associated with concussion . The thiCervical stiffness in this context relates to the ability of the neck musculature and osteoligamentous structures to withstand displacement and has been proposed as a potential preventative strategy for reducing the risk of concussion, as well as the severity of sub-concussive trauma . In thisThe limited sporting codes included in the identified studies are considered “contact sports” and were most likely recognized for the increased risk of concussion in the participating athletes . It shouTwo impactful studies reported a substantial reduction in concussion incidence as a result of pre-participation whole body exercises , 53. TheThe findings of this research come at a time of increased global attention on concussion prevention to improve welfare of participants involved in sport.This scoping review included articles published in English language only, due to resource and budget constraints. In doing so, it is possible that articles in other languages that may have met the study’s inclusion criteria were excluded in the search strategy. A second limitation is that a timeframe of the past 15 years was used, which may have excluded older articles that met the inclusion criteria. Although the available evidence is limited, the use of the scoping review methodology, rather than a systematic review, allowed for discussion and analysis of a broad spectrum of relevant studies with varied methodologies.The results of this scoping review are presented at a time of an increased global scrutiny of concussion prevention to improve the welfare of participants involved in sport and reveal a dearth of literature addressing physical preparation strategies to reduce or prevent the incidence of concussion. The small amount of research in this area has shown conflicting results for modifiable risk factors relating to neck size, neck strength, and neck stiffness. Future research should assess the effects of both proprioceptive and dynamic strengthening of the neck and surrounding musculature to reduce forces transmitted to the brain or to increase resilience during participation in sports. The potential of effective protective mechanisms to reduce the incidence and the effects of concussion warrants further research.Additional file 1. Appendix A.Additional file 2. Appendix B.


Buzz pollination encompasses the evolutionary convergence of specialized floral morphologies and pollinator behaviour in which bees use vibrations  to remove pollen. Floral buzzes are one of several types of vibrations produced by bees using their thoracic muscles. Here I review how bees can produce these different types of vibrations and discuss the implications of this mechanistic understanding for buzz pollination. I propose that bee buzzes can be categorized according to their mode of production and deployment into: (i) thermogenic, which generate heat with little mechanical vibration; (ii) flight buzzes which, combined with wing deployment and thoracic vibration, power flight; and (iii) non-flight buzzes in which the thorax vibrates but the wings remain mostly folded, and include floral, defence, mating, communication, and nest-building buzzes. I hypothesize that the characteristics of non-flight buzzes, including floral buzzes, can be modulated by bees via modification of the biomechanical properties of the thorax through activity of auxiliary muscles, changing the rate of activation of the indirect flight muscles, and modifying flower handling behaviours. Thus, bees should be able to fine-tune mechanical properties of their floral vibrations, including frequency and amplitude, depending on flower characteristics and pollen availability to optimize energy use and pollen collection. The characteristics of buzz-pollinating vibrations, including frequency and amplitude, can be controlled through dynamic adjustment of the mechanical properties of the thorax, activation of indirect flight muscles, and flower handling. One of the characteristics of modern biology is the breakdown of the boundaries which separate its subdivisions, and nowhere is this more fruitful than in behavioural studies where mechanics and physiology are integral to a more profound understanding.Written nearly 65 years ago, in the context of studying insect flight, the quote above also captures the enduring importance of multidisciplinary approaches to the study of the interactions between plants and their pollinators. Flowers and their visiting pollinators often interact intimately, and the properties of both floral structures and insect morphology, physiology, and behaviour become essential in determining the ecological and evolutionary outcomes of this interaction . The advFlowers across many different families and involving >20 000 species have evolved tubular structures that keep pollen grains locked inside . AlthougApis mellifera) and many species in the families Andrenidae and Megachilidae, have never been observed buzzing flowers for pollen  is caused indirectly by changing the conformation of the thorax . Wings a−1 during flight  scales negatively with body mass  and, in Ultimately all vibrations produced by bees trace back their proximate origin to the contraction of the energy-demanding indirect flight muscles described above. Although usually considered separately, vibrations produced in different behavioural contexts can be considered in a single conceptual framework . Using tApis and Bombus, non-flight thermogenesis is used to regulate the temperature of the colony  IsoThe rate of heat production during non-flight thermogenesis is thought to be under the control of the bee. In honeybees, there is a 1:1 correspondence in action potentials and muscle contraction during shivering . The freThe transition from thermogenic to flight-associated thoracic vibrations involves changes in the rate of DV action potentials which shorten the DV muscle and start stretch activation of the DL muscles . The strWingbeat frequency increases with the frequency of action potentials . HoweverWingbeat frequency is negatively associated with body size across insect orders .Non-flight thoracic vibrations that are not associated with thermogenesis encompass oscillations produced during a wide range of behavioural contexts, but which share two properties: (i) the thorax of the bee oscillates in response to deformation of the cuticle driven by contractions of the indirect flight muscles; and (ii) wings remain undeployed; that is, folded in a resting position above the thorax and abdomen of the bee, limiting their displacement and becoming decoupled from the indirect flight mechanism . FoldingMelipona spp.) can apparently use the airborne sounds associated with these vibrations to communicate with nestmates about floral resources  use vibrations during courtship and mating  as thoracic contractions during tethered flight (100–150 Hz). The strain of muscles (percentage muscle elongation) during defence buzzing has a similar range to that during flight (1–3%). However, comparison of thorax contraction frequency and strain in tethered flight shows that frequency and strain are positively associated  in B. terrestris and Xylocopa spp. are lower in defence than in flight  of defence buzzes is higher (M. seminigra shows a 2- to 5-fold increase in peak-to-peak displacement and velocity amplitude of defence vibrations (Non-flight thoracic vibrations are deployed by some bees (and some wasps and flies) as a warning or defensive signal . Defencesociated . Separatt buzzes . This inXylocopa  and in Ms higher . SimilarBombus, Centris, Eulaema, and Xylocopa, the floral:flight frequency ratio is between 1.3:1 and 2.5:1, while in smaller bees including Dialictus, Exomalopsis, Nomia, Agapostemon, Augochloropsis, Pseudoaugochlora, Melipona, and others it is between 1:1 and 2:1  than defence buzzes , with the concomitant increase in energy required to maintain these forced oscillations  as well The resonance and driven oscillation hypotheses are not mutually exclusive, and both might play a role in explaining the mechanism producing high-frequency vibrations during non-flight behaviours. On one hand, wing folding, activation of control muscles, and muscle stiffening probably change the natural frequency of the thorax, leading to a new resonant frequency compared with that under flight  Esch an. On the Buzz-pollinating bees extract pollen from flowers with enormously different sizes, shapes, material properties, and, presumably, different vibrational properties . Flexibibee) determined by both the mass of the bee (mbee) and the acceleration (abee) that it can generate using its thoracic power muscles  reduces the acceleration that the bee can produce in the coupled bee–flower system (Because of the functional connection with pollen release, increasing velocity/acceleration amplitudes of the vibrations applied to pollen-containing floral structures should be favoured in buzz-pollinating bees. Theoretical work suggests that the rate of pollen release from poricidal anthers is positively related to anther velocity . In addir system . Thus, tr system , it woulr system . In addir system . In flowr system . From thr system .Pedicularis, The mechanistic description of how bees generate and modulate vibrations across different behavioural contexts suggests that, during vibratile pollen collection, bees should be able to fine-tune their floral vibrations while visiting different types of flowers to optimize their pollen collection and energy use. Indeed, empirical studies show that bees adjust the length and number of buzzes in response to pollen availability in poricidal flowers (e.g.


The term microbiome means not only a complex ecosystem of microbial species that colonize our body but also their genome and the surrounding environment in which they live. Recent studies support the existence of a gut-retina axis involved in the pathogenesis of several chronic progressive ocular diseases, including age-related macular disorders. This review aims to underline the importance of the gut microbiome in relation to ocular health. After briefly introducing the characteristics of the gut microbiome in terms of composition and functions, the role of gut microbiome dysbiosis, in the development or progression of retinal diseases, is highlighted, focusing on the relationship between gut microbiome composition and retinal health based on the recently investigated gut-retina axis. The terms microbiota and microbiome are often used interchangeably, although they have different meanings: the first refers to the prokaryotic organisms (bacteria and archaea) and eukaryotes  that coexist in symbiosis with us, the latter, which for a long time was only referred to these microorganisms genomes, today takes a broader meaning. The term microbiome means a complex ecosystem of microbial species that colonize our body, their genome, and the surrounding environment in which they live .In other words, the microbiome refers to both microorganisms and their “theater” of activity which also includes microbial metabolites, mobile genetic elements  where they form a real ecological niche. Therefore, the microbiome is considered a micro-ecosystem integrated into a macro-ecosystem represented by the host with whom it interacts in a crucial way .Understanding the role of the microbiome, particularly the one belonging to the gastrointestinal (GI) tract, represents one of the most active fields of biomedical research. Microbiome composition constitutes a fundamental aspect if we want to understand its physiology and pathological implications. It comprises a microbial community that exceeds 100 trillion microorganisms, distributed with a density of 1011–1012 per milliliter. To get an idea of the biological role of this population, just think that, while the human genome consists of approximately 23,000 genes, the gut microbiome encodes more than 3 million genes and produces thousands of metabolites. It is, therefore, evident that, since it interacts in a symbiotic way with our organism, performing immune and metabolic functions of fundamental importance, the maintenance of its qualitative and quantitative composition is essential for the maintenance of our health .This review aims to underline the importance of the gut microbiome in relation to ocular health. After a brief introduction on the gut microbiome in terms of composition and function, the review highlights the role of gut microbiome dysbiosis in the development or progression of chronic retinal diseases, such as Age-Related Macular Degeneration (ARMD), Diabetic Retinopathy (DR), or Retinitis Pigmentosa (RP). Based on the recently investigated gut-retina axis, this excursus will focus on the relationship between gut microbiome composition and retinal health.2) between the host, antigens, and environmental factors in the human body. The human gut microbiome varies taxonomically and functionally in each of the anatomical regions of the GI tract as these have different characteristics in terms of physiology, pH, oxygen tension, digestive flow rate, availability of substrates, and host secretion  of life and during puberty, and then stabilizes by assuming a composition that will also be maintained in adults and which, in healthy individuals, remains mostly stable . HoweverThe microbiome of each subject is unique and regulates several physiologic functions of the host, including metabolism and development, and maintenance of immune homeostasis. Although the research in this field is still preliminary, it is well documented that a gut microbial imbalance may be responsible for dysfunctions affecting the host, contributing to the pathogenesis and/or progression of a wide spectrum of pathologies affecting various organs and systems .The close physiological link between host and microbiome has several metabolic outcomes, and a specific effect on the host immune systems. Instead, a large body of evidence indicates that several microbial metabolites profoundly regulate the immune system via host receptors and other target molecules. The relation between the microbiome and the host is at least partly mediated by metabolites synthesized by microbes which, acting as signal molecules, regulate the neuro-immune-inflammatory axis of the host. This link physiologically connects the intestine to other organs and systems . In thisPathological conditions causing intestinal dysbiosis and altering the production of microbial metabolites are responsible for dysregulation of the immune system and metabolism that favors the onset of diseases with immune and chronic inflammatory components. Dysbiosis is any change to the composition of resident commensal communities leading to a reduction in the number of symbionts and/or an increase in the number of pathobionts. As the commensal microbiome regulates the maturation of the mucosal immune system, while the pathogenic microbiome causes immunity dysfunction, the imbalance between them causes a non-specific inflammation that can predispose susceptible subjects to inflammatory pathologies .The gut microbiome regulates essential functions for the maintenance of general human health. It influences the immune system and homeostasis both locally (within the gut) and systemically. Therefore, in this context, a key role is played by the increased intestinal permeability (leaky gut) and the related microbial translocation. That contributes to the chronic systemic inflammation process . The gasCompromised tight junction function is associated with several clinical intestinal and systemic conditions . HoweverGut dysbiosis may induce the release of zonulin that provokes the crossing of the luminal content through the epithelial barrier. This is responsible for the release of pro-inflammatory cytokines that, themselves, enhance the intestinal permeability causing a vicious loop leading to a massive influx of dietary and microbial antigens triggering the activation of T cells. Depending on the host genetic predisposition, activated T cells may remain in the gastrointestinal tract, causing inflammatory diseases of the gut  or migrate to several different organs causing systemic chronic inflammatory diseases . In otheMoreover, gut dysbiosis could be related to the formation of the inflammatory form of lipopolysaccharide (LPS), a glycolipid found on the outer membrane of Gram-negative bacteria formed by a lipid A (endotoxin), a non-repeating core oligosaccharide and a distal polysaccharide composed of O-antigen . The relLipid A then initiates a signaling cascade resulting in activation of various proinflammatory pathways (predominantly NF-κB) and increases oxidative stress upon binding to Toll-Like Receptor 4 (TLR4) , resultiLow-grade inflammation characterizes the aging process resulting from environmental, genetic, and epigenetic events throughout life. Indeed, typical aging features are age-related diseases that share an inflammatory pathogenetic origin. The low-grade inflammation linked to the aging process has been termed “inflammaging” and is considered a significant risk factor for morbidity and mortality in elderly people . This prAging is defined as a process that is genetically determined and modulated by the environment. The gastrointestinal tract is involved in this process as it is related to degeneration of the enteric nervous system, alteration of intestinal motility and of the epithelial-mucosal barrier, with a relative reduction of the defense function favoring the development of gastrointestinal pathologies. In this context, immunosenescence, defined as a deterioration of the immune system, plays a key role in the aging process . MoreoveImmunosenescence and “inflammaging” seem to contribute also to the development of age-related eye-diseases.Among all the ocular tissues, the retina is considered a privileged tissue from the immune standpoint. It is protected by three layers , as well as by “resistance” and “tolerance” strategies that safeguard it from any insults coming from the internal and external environment. Moreover, it is also protected by its own defense systems such as microglia and the complement system to maintain retinal homeostasis .The retina is highly vulnerable due to its poor renewal and repair capacity, so even minor damage can have devastating consequences. Aging negatively impacts the retina, which is at increased risk of developing various degenerative diseases such as diabetic retinopathy, glaucomatous retinopathy, and age-related macular degeneration. In fact, the three layers protecting the retina undergo significant changes during aging. Physical barriers become to be weakened due to age-related dysfunction of endothelial and glial cells. Immune regulatory signals are also altered. All the changes make the retina more susceptible to oxidative stress, hyperglycemia, and increased intraocular pressure .The mechanisms responsible for the development of age-related macular degeneration are still not fully understood. However, it seems that immunosenescence , involves the retina compartment and plays an important role in retinal disease. Current data suggest that age-related macular degeneration is a systemic immunologic disease with local expression due to the decline of the ocular downregulatory immune environment. A sign of an altered immune response is represented by the deposits that gradually accumulate in the retinal pigment epithelium first and by the drusen later, constituting an antigenic stimulus that favors a marked activation of the immune system, especially in predisposed subjects .During aging, all defense systems become less efficient, and the morphofunctional and immune changes related to age are concomitant to chronic low-level inflammation . The “inAging strongly affects the composition of the microbiome because it contributes altering the intestinal epithelial barrier, whose function is fundamental to maintaining homeostasis. This barrier layer includes various elements such as the epithelium, the mucous layer, antimicrobial peptides, and IgA secretory immunoglobulins. These components are closely connected with the resident microbial community and suffer deterioration too, related to aging . With agThe age-related microbiome alteration may affect general health Alteration in gut microbiota composition may, particularly, alter the brain aging since it is an integral part of the gut-brain axis. The interactions between the central nervous system, the enteric nervous system, and the gastrointestinal tract have been extensively studied . A serieThe health of the microbiome is essential in maintaining the human body in a homeostatic state. Aberrations in the gut microbiota and its metabolites induce systemic inflammation via stimulation of both the innate and adaptive response of the immune system. This inflammation may proceed to destroy tissues throughout the body, leading to the onset of many diseases, including the ocular ones, as shown in both human and animal studies .The eye is prone to develop inflammatory diseases even without an infectious component, appears to be influenced by dysbiosis of the gut microbiome. There is a, relevant association between inflammatory intestinal diseases and ocular diseases. Indeed, ten percent of subjects suffering from inflammatory bowel disease manifest ocular diseases  . SeveralSeveral retinal diseases such as ARMD, DR, and RP may be influenced by the gut microbiome suggesting a direct gut-retina axis.ARMD is a multifactorial disease resulting from a complex combination of genetic and environmental factors. As microbiome integrity plays a crucial role in the host regulation and promotion of immunity, as discussed earlier, intestinal microbiota could represent a candidate for interplay between the genetic risk and environmental factors contributing to ARMD .Data support that the higher translocation of gut metabolites and products permitted by the increased intestinal permeability related to an altered gut microbiota may modulate retina-specific immune cells . InteresAnaerotruncus and Oscillibacter as well as Ruminococcus torques and Eubacterium ventriosum were higher in patients with ARMD, whereas Bacteroides eggerthii were higher in controls. Authors speculate this diversity may be ARMD linked because the first genera (Anaerotruncus and Oscillibacter as well as Ruminococcus torques and Eubacterium ventriosum), increased in these patients, are associated with glutamate degradation and increased arginine biosynthesis pathways , lipopolysaccharide, aromatic amino acids, and their metabolites contribute to the development of type 2 diabetes through different metabolic and immunologic pathways . On the Bacteroides caecimuris, typically less represented in the healthy gut microbiome, was significantly higher in diseased mice in comparison to control mice. On the contrary, affected mice were missing the most common genetic variants  typical of a healthy gut microbiome  loads. The study showed that the ingestion of this specific strain suppressed cell death .Lactobacillus paracasei KW3110. Therefore, they conducted experimental evaluations to observe the effect of long-term intake (6 months) of Lactobacillus paracasei KW3110 on age-related inflammation and altered gut microbiota in physiologically aged mice. The results showed effects on gut microbiota by modulating the age-related changes of bacterial composition, including bifidobacteriaceae strains, and the anti-inflammatory effect highlighted by the significant reduction of cytokines and chemokines in the mice treated compared to controls . Furthermore, Lactobacillus paracasei intake suppressed retinal inflammation by reducing cytokine-producing macrophages and the loss of age-related retinal cells (Lactobacillus paracasei to suppress inflammation on photoreceptor cells in a murine model of light-induced retinopathy. Although additional clinical research is needed to translate research into clinical practice, authors conclude that these data may suggest that this specific strain of Lactobacillus paracasei may have a preventive effect against degenerative retinal diseases (The positive results led the researchers to further investigate the molecular mechanism responsible for the protective effect on the retina produced by the al cells . Likewisdiseases .A lot of work still needs to be done to identify specific probiotic strains related to particular diseases. The microbiota modulation through probiotics or next-generation beneficial microbes constitutes a future perspective for developing either nutritional or pharmaceutical agents to maintain health.Alongside probiotics biotherapy, there is also the use of prebiotic, a class of substances that, in 2016, have been defined by a panel of experts in microbiology, nutrition and clinical research, as “a substrate that is selectively utilized by host microorganisms conferring a health benefit” . FructooIndividual microbiome composition can be influenced by several lifestyle factors such as dietary habits, socioeconomic status, education, medical care, and environmental factors. It is well known that drug use, lack of exercise, smoking, and an unhealthy diet may compromise the balance of the microbiome ecosystem .Among all these factors diet is, probably, the most critical as it may influence both the richness and diversity of microbiota. For example, red wine- and tea-derived polyphenols and vitamin D can modulate potentially beneficial bacteria. Recent research demonstrates that dietary fibers, such as inulin, galacto-oligosaccharides, arabinoxylans, and oligofructose, promote several beneficial bacteria and suppress potentially harmful species. Concerning macronutrients, the quantity and type of fat modulate both beneficial and potentially harmful bacteria, as well as the Firmicutes/Bacteroides ratio in the gut. Moreover, the type, amount of dietary proteins, and cooking methods have differential effects on the gut microbiota. Further clinical investigation about the role of micro- and macro-nutrients on the microbiome is needed .In this review, we have described the importance of the microbiome in maintaining general health, as dysbiosis is strongly related to autoimmune, inflammatory, and metabolic diseases. We have described how commensal microbes affect all aspects of immune development and homeostasis in health and disease.Increasing evidence demonstrates that the intestinal microbiome can influence the intestinal area and other tissues distant from the intestine, including the eye. There is a broad agreement on the existence of a gut-eye axis. Accordingly, the eye can be strongly influenced by the intestinal microbiota. Indeed, microbiota abnormalities are often associated with several eye diseases, all attributable to an alteration of the immune system and with an inflammatory component such as ARMD.The significant role of the microbiota in modulating the physiological and pathological processes of our organism is now a consolidated concept. This opens new scenarios for promising therapeutic targets and treatment of many extra-intestinal pathologies, including ocular comorbidities.It is becoming clear that the manipulation of the intestinal microbiota and the consequent maintenance of the physiological composition of the ocular one both seem to represent valid alternatives for the prevention and/or treatment of eye diseases. Although the clinical efficacy of probiotic therapy warrants further investigations, it represents a promising field of research with predictable exciting results.GS, ET, and AM conceptualized and wrote the manuscript. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The endothelium is considered the largest organ of the body, composed of a monolayer of endothelial cells (ECs) lining the interior surface of blood and lymphatic vessels . ECs areDespite the different phenotypic characteristics displayed by ECs in various organs and tissues, endothelial dysfunction shares some common features, such as reduced vasodilation, inflammation, oxidative stress and a prothrombotic state . Thus, tGiven the different clinical and laboratory methods for monitoring endothelial dysfunction and considering its systemic nature and reversibility in early stages, this condition has been proposed as an attractive therapeutic target in many clinical conditions, with a potential emerging role for specific pharmacological interventions and tailored exercise-based rehabilitation strategies ,9.In this Special Issue, we aimed to collect some original research articles and reviews on the mechanisms and diagnosis as well as the prognostic and therapeutic implications of endothelial dysfunction as a biomarker of inflammation, oxidative stress and vascular disease.Thus, a number of high-quality reviews focusing on different aspects of the complex interplay between endothelial dysfunction, inflammation and CV risk were published, pointing out the importance of some molecular mechanisms. The Notch pathway emerged as a master regulator of angiogenesis, with an important role in transducing the signals provided by the blood shear stress to the endothelium . The carSome preclinical and functional studies also fell within the scope of this Special Issue. In an intruding article by Kan et al. , the effOther pertinent studies ,22,23 ha


Approximately 140 million babies were born worldwide in 2020, yet nearly all coronavirus disease 2019 (COVID-19) vaccine clinical trials have excluded pregnant and breastfeeding individuals from participating. In the meantime, pregnant women and their clinicians have little data to make informed decisions on immunization safety. With the continued global escalation of COVID-19 cases and studies demonstrating greater morbidity from COVID-19 in pregnant women , the inclusion of pregnant women and breastfeeding women in COVID-19 vaccine trials are urgently needed to identify the potential risks and benefits in this population, as well as to the fetus or nursing infant.Similarly, in newborns there is a paucity of data on any benefit of the mRNA COVID-19 vaccine to draw definitive conclusions. In a small study, Collier and colleagues reported that receipt of the mRNA COVID-19 vaccine was immunogenic in nine participants, and vaccine-elicited antibodies could be identified in infant cord blood . These ain vitro fertilization (IVF) treatment should avoid vaccinating in the days leading up to their embryo transfer or egg collectionSome Australian clinicians have recommended that women undergoing Lastly, the short-term and long-term effects of COVID-19 vaccination in pregnant and lactating women, the fetus, and infants remain unanswered. Since the immune response to COVID-19 vaccination in pregnant and breastfeeding women cannot be inferred from that of non-pregnant and non-breastfeeding women, we must highlight the importance of enrolling these individuals in clinical trials. The long-term safety data that speak most clearly to the question of whether the COVID-19 vaccines benefit pregnant women and newborns should be obtained from robust clinical trials. Emerging evidence suggests that global maternal and fetal outcomes have worsened during the pandemic, with a significant increase in maternal and fetal mortality (particularly in low-income and middle-income countries), ruptured ectopic pregnancies, and maternal symptoms of depression . Such faHere, we suggest that the COVID-19 vaccine should be tested as a critical prevention strategy for pregnant women and their children in ongoing and future clinical trials. We acknowledged that in the absence of a standard vaccine to serve as the control, the use of placebo may be considered; however, the ethics of administering a potentially ineffective therapy to combat a morbid viral infection is unquestionably harmful. This argument is compounded by the risk posed to both the mother and the fetus. Ultimately, these trials may have lower enrollment given the potential risk of contracting COVID-19 when given the placebo. Nevertheless, we hope these trials will elucidate the efficacy, safety, and long-term outcomes of COVID-19 vaccination in pregnant mothers and the developing fetus. And we strongly suggest monitoring the incidence of maternal fever, acetaminophen use, rate of pregnancy loss, developmental outcomes in the newborn, and ADHD in offspring of pregnant women who have received COVID-19 vaccination. By monitoring the outcomes for pregnant and lactating women and their babies, these investigations will further promote informed decision-making for COVID-19 vaccination during pregnancy and lactation, and may lead to a reduction in vaccine-hesitancy.As the COVID-19 pandemic continues, a public health obligation exists to evaluate pregnant women and their children  in well-designed and well-funded COVID-19 vaccine trials to identify and implement appropriate prevention and care based on strong evidence.CY and ST conceived the manuscript. CY and HZ conducted the search and drafted the manuscript. CY, HZ, and ST revised the manuscript. All authors contributed to the article and approved the submitted version.This study was supported by the Canadian Institutes of Health Research (CIHR) (Grant No. 177747).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Furthermore, we found that the colorectal cancer microbiome can promote inflammation, cancer progression  and cancer prevention  by increasing and decreasing certain metabolites such as histamine, glutamine and pyruvate. Thus, modulating the gut microbiome could be a promising strategy for the prevention and treatment of CRC.The human gut microbiota plays a dual key role in maintaining human health or inducing disorders, for example, obesity, type 2 diabetes, and cancers such as colorectal cancer (CRC). High-throughput data analysis, such as metagenomics and metabolomics, have shown the diverse effects of alterations in dynamic bacterial populations on the initiation and progression of colorectal cancer. However, it is well established that microbiome and human cells constantly influence each other, so it is not appropriate to study them independently. Genome-scale metabolic modeling is a well-established mathematical framework that describes the dynamic behavior of these two axes at the system level. In this study, we created community microbiome models of three conditions during colorectal cancer progression, including carcinoma, adenoma and health status, and showed how changes in the microbial population influence intestinal secretions. Conclusively, our findings showed that alterations in the gut microbiome might provoke mutations and transform adenomas into carcinomas. These alterations include the secretion of mutagenic metabolites such as H Cancer is generally known as a disease of the genome arising out of a combination of genetic mutations, epigenetic modifications and altered signaling pathways. These mutations occur diversely, sometimes with undetermined origins. However, some cancers are associated with infectious agents, and some appear in tissues that are exposed to microbiota  . 14 bacteria, comprising 103 species, in the human colon. This signifies that bacterial genes outnumber human genes in the human body [Microbial agents constitute about 90% of the cells in the human body, and it is estimated that there are 10man body ,3,4,5. Aman body ,7. The transformation of adenoma into carcinoma tumors in colorectal cancer (CRC) requires mutations in the cancer-driver genes, which normally takes up to 10 years, and additional mutations accelerate its progression. There is also a hypothesis that considers the role of the microbiome in CRC, mostly adenomas. The driver–passenger hypothesis states that driver bacteria cause this transformation by triggering DNA damage and persistent inflammation. On the other hand, the tumor microenvironment provides another growth site for opportunistic bacteria called passengers. This even suggests that some probiotic bacteria may take advantage of the tumor microenvironment and prevent the progression of cancer .With the advent of high-throughput technologies, researchers can quantify molecular changes at different cellular levels. These technologies can reveal the complete picture of cell metabolic activity in one snapshot and can unveil the metabolic patterns and function of cells, including the activities of enzymes, gene products, transporters and chemical reactions. Therefore, they would be suitable tools for the metabolic profiling of different cells, both to identify differences between organs and to distinguish metabolic diseases ,11,12,13Genome-scale metabolic models (GEMs) provide quantitative information about the metabolism of large-scale systems . Using GFusobacterium spp. in the production of glutarate and in the suppression of butyrate and acetate levels in feces [Additionally, previous studies have explored changes in the bacterial population and their potential impact on CRC initiation or development, as well as metabolic alterations in the CRC tumor lumen and blood serum. By using the same modeling approach, they highlighted the role of in feces ,24. SincThe community modeling of the microbiome requires the integration of individual bacterial metabolic models (GEMs) based on the proportions of different bacteria present through ecological modeling. In this work, we made use of the MGYS00001248 data , an ecolTo select the GEMs’ best matching with existing metagenome data, we firstly tried to combine both publicly available databases, AGORA and EMBL. In 2016, AGORA models (consisting of 773 GEMs of well-known bacteria) were reconstructed to investigate the reciprocal association of bacterial behaviors and human metabolic diseases . The AGOAlthough using the rarefaction method for metagenomic data analysis is controversial ,30,31, iSince diet can also affect the survival of bacterial models in the community model, we postulated that the environmental conditions of the microbial population were food-intensive, so all the simulations were performed under the rich diet. Finally, from 160 mucosal microbiome samples, 88 microbiome community models were constructed based on AGORA and Pan models .The NMPC , which simulates the capacity of the microbiota to create the intestinal lumen environment, was calculated by FVA . This siStudies have demonstrated that the CRC microbiota and its healthy counterpart have diverse patterns , which aWe used pairwise PLS-DA to find metabolic patterns among the meta-models of each group. PLS-DA is an efficient tool for analyzing metabolomic data . It can p-values < 0.05 were considered significant for the pathways detected in MSEA. Therefore, the results show that microbiota-derived metabolites could be involved in CRC metabolism by altering pathways under different conditions during CRC progression.Metabolite set enrichment analysis (MSEA) was used to determine the role of metabolites in human cell metabolism. For this purpose, VIP was used to extract metabolites that were involved in human metabolism, filtered by the VMH database. This analysis was performed for metabolites that were increased or decreased in a pairwise analysis of groups. l-glutamine, l-tyrosine, pyruvate, tyramine, tryptamine and ten other metabolites were significantly increased in the normal meta-model. Furthermore, metabolites such as taurine, l-serine, chondroitin sulfate, mannose, putrescine and 73 other metabolites were decreased in this comparison  apoptosis and invasion.Several studies have examined the association of metabolites with CRC. In vivo and in vitro environments cannot accurately indicate the sources of metabolic changes, especially in CRC, where the gut microbiome is an inseparable part. Based on the results of our microbiome community modeling and simulating the intestinal lumen metabolic environment  . AlthougThe complete urea cycle converts excess nitrogen to urea and excretes it in the urine. This complete cycle is mainly active in the liver, but enzymes in other cells are responsible for the synthesis of the intermediates of this cycle through the use of nitrogen according to cells’ needs. Extrahepatic urea cycle enzymes are the only intracellular producers of arginine, citrulline and ornithine, which are precursors for the synthesis of polyamines, nitric oxide (NO) and proline. In cancer, unlike in liver cells that secrete nitrogen, urea cycle mediators, including arginine, proline and ornithine, enter anabolic pathways, and changes in their enzymes contribute to tumor growth . As ammoInterestingly, arginine, proline and ornithine, which are important in the urea cycle, were increased in the adenoma models. Furthermore, the increase in arginine and proline metabolism in human cells was increased according to the MSEA results. Arginine and proline replace glucose in the energy supply under glucose deprivation and energy deficiency. The enzyme arginine succinate lyase (ASL) is highly expressed in various cancers, including CRC, which produces arginine, NO and citrulline. Furthermore, the production of intracellular NO from arginine is dependent on this enzyme, so the inhibition of this enzyme has similar effects on the reduction of NO. NO promotes cell proliferation .The amount of secreted glutamine, an important hallmark metabolite of cancer metabolism, was increased in the carcinoma meta-model. Cancer cells use glutamine during glutaminolysis for cell growth and proliferation. This is one of the hallmarks of cancers, and many treatment strategies have been developed based on it. Cancer cells use mediators created in the glutaminolysis cycle to replenish the TCA cycle . GlutamiPyruvate is present in anaplerotic reactions in ovarian cancer and affects mitochondrial functions . By affeDespite the principle of ignoring the TCA cycle and the priority of aerobic glycolysis in cancer cell metabolism, the TCA cycle was increased in the MSEA of the adenoma meta-model. The TCA is involved in the production of required macromolecules and the energy production of cancer cells . From thThe effects of hormones on pathogenicity and its origin are usually considered in the physiology of a human body. The MSEA results revealed the enrichment of thyroid hormone synthesis in the carcinoma meta-model. There have been many studies on the effects of thyroid hormone and nuclear receptors on tumorigenesis and cancer cell proliferation. Despite the heterogeneity in these studies, increased receptor expression in CRC and increased risk in patients with hyperthyroidism may be of interest. It should also be noted that, given the environmental uptake of cancer cells, the role of microbiome metabolism in the production and explanation of the effect of this hormone could be important ,57.Serotonin and dopamine were also increased in the adenoma meta-model. These are neurotransmitters produced by the central nervous system and the gastrointestinal tract. Clinical studies have proven their effects on the growth of tumors such as CRC ,62,63,64Other pathway alterations involved cardiolipin and ETC biosynthesis, which were enriched in the MSEA results for the adenoma meta-model. Cardiolipin is present in the inner membrane of the mitochondria; its overexpression and interaction with ETC proteins in CRC cells increases and optimizes the efficiency of mitochondrial respiration . The inhThe gut microbiome can also accelerate the production of purine and pyrimidine precursors, supporting cell proliferation and energy supply. Our results show significant increases in nucleotides, DNA precursors and purine metabolism in the adenoma and carcinoma models. Adenine, adenosine and deoxy-adenosine, deoxy-cytidine, uridine, guanosine and thymidine were found among the enhanced metabolites for both models. Thymidine catabolism is a metabolic strategy of cancer cells that provides them with energy by supplying carbon to the glycolytic pathway under nutritional deprivation .Phenolic acids and cobalt chloride have anticancer effects ,70. The Our carcinoma meta-data model indicated the prevention of apoptosis due to a significant reduction in the synthesis of taurine, spermidine, phosphatidylethanolamine and phenolic acid metabolites. Taurine stimulates apoptosis, and its secretion in the carcinoma microbiome may be reduced ,72. SperIn this study, we investigated microbiome metabolism in terms of the abundances of microbiota and their distinct metabolomics in different tumors of CRC. For this purpose, we used metabolic modeling and metabolomics analysis approaches including community metabolic modeling (CMM), principal component analysis (PCA) and metabolite set enrichment analysis (MSEA). We used metagenomics and the relative abundances of microbiota data as the input for microbiome metabolic modeling. The relative abundances of microbiota in different tumors of CRC were extracted from the MGnify database (study MGYS00001248). The dataset consists of mucus biopsies from 160 individuals harvested by colonoscopy and examined histologically , and 61 To create a CMM, we require (1) the relative abundances of presented and recognized bacteria, and (2) individual GEMs that match the recognized bacteria. For data consistency, we manually modified the taxonomy nomenclature because metagenomic data often do not have sufficient resolution at the strain, species and genus levels for the bacteria. For the compatibility of the data with the taxonomy assignments, high-resolution taxon data were matched with AGORA GEM models derived from the Virtual Human Metabolism  (VMH) daTo modify the taxonomy nomenclature, we used the Disbiome database . This daData normalization is challenging in this domain. One of the most applicable methods is rarefaction, the applications of which in metagenomics and microbiome analysis have been discussed ,30,31. TLarge-scale community modeling requires the integration of the relative abundances of metagenomics data into metabolic models. For this purpose, we used the mgPipe pipeline that is the part of the microbiome modeling toolbox in the COBRA toolbox. The mgPipe function includes: (1) the analysis of the microbiota abundances per sample; (2) the construction of microbiome models and adding lumen-transport reactions by connection to a specific diet and uptake/secretion behavior; and (3) the simulation of models and the lumen metabolic environment under the given diet by flux variable analysis (FVA). These simulations demonstrate the maximal capability for metabolite production in a lumen environment: the so-called net maximal production capacity (NMPC). The metabolic modeling of the microbiome community was performed using the COBRA toolbox in the MATLAB 2017b environment with the IBM CPLEX 12.8 solver. We used the mgPipe pipeline and AGORA 1.03  models aNMPC data show the maximum microbiota community capacity of each sample in creating the intestinal lumen metabolic environment. This information was used to analyze and compare within groups and between groups.PCA and partial least-squares discriminant analysis (PLS-DA) are two methods that are important in the analysis of metabolomic data . In thisThe variable important projection (VIP) used PLS-DA information to display each of the variables in the first component of each PLS-DA model.The PCA and PLS-DA were performed in the SIMCA software environment of UMETRICS company version 14.1. Autofit was performed for PCA and PLS-DA modeling with default settings.The cross validation of the PCA and PLS-DA was performed using the SIMCA software, by full cross validation. The method used the Krzanowski and PRediction Error Sum of Squares (PRESS) methods and returned the significance of the models ,82.MSEA  is an apOur community metabolic models unveiled the roles of the gut microbiome in CRC development, as well as its significant influence on adenoma and carcinoma tumors, from provoking mutations to facilitating the spread, homeostasis and survival of colorectal cancer cells.


The present review will focus on evidence demonstrating the prioritization in visual processing of fear-related signals in the absence of awareness. Evidence in hemianopic patients without any form of blindsight or affective blindsight in classical terms will be presented, demonstrating that fearful faces, via a subcortical colliculo-pulvinar-amygdala pathway, have a privileged unconscious visual processing and facilitate responses towards visual stimuli in the intact visual field. Interestingly, this fear-specific implicit visual processing in hemianopics has only been observed after lesions to the visual cortices in the left hemisphere, while no effect was found in patients with damage to the right hemisphere. This suggests that the subcortical route for emotional processing in the right hemisphere might provide a pivotal contribution to the implicit processing of fear, in line with evidence showing enhanced right amygdala activity and increased connectivity in the right colliculo-pulvinar-amygdala pathway for unconscious fear-conditioned stimuli and subliminal fearful faces. These findings will be discussed within a theoretical framework that considers the amygdala as an integral component of a constant and continuous vigilance system, which is preferentially invoked with stimuli signaling ambiguous environmental situations of biological relevance, such as fearful faces. Emotional facial expressions are particularly salient stimuli in our environment ,2. FacesAn important aspect of threat-related stimuli is their ability to elicit behavioral and neurophysiological responses without access to perceptual awareness. For instance, the processing of salient emotional stimuli, like threat-related stimuli—even when occurring outside the focus of attention—is given privileged and rapid access to attentional resources, compared to the processing of non-emotional stimuli , as demThis review will present evidence showing that threat-related stimuli are preferentially processed, even in the absence of awareness, and are able to facilitate responses to visual stimuli in the surroundings. More precisely, evidence emerging from patients with lesions to the visual cortices and visual field defects will be reviewed, since they offer a unique model to explore the mechanisms and the neural underpinnings of unconscious threat implicit processing. In addition, this review will document the relevance of the right hemisphere for the visual processing of fearful facial expressions in the absence of awareness.Studies of patients with cerebral lesions, especially to the visual cortices, have provided important information about the properties and the neural underpinnings of non-conscious perception of emotional stimuli and the notion that processing of fearful stimuli is prioritized, compared to other emotional signals.In a recent series of studies on implicit processing of emotional stimuli, patients with visual field deficits due to post-chiasmatic lesions typically performed at chance when they had to discriminate the visual features and the emotional content of stimuli presented in their blind field, or to guess the presence or absence of visual stimuli presented in the blind field ,18,19,20Notably, the ability of hemianopic patients to selectively process fear in the absence of awareness appears to represent a different phenomenon from the abilities demonstrated by patients with affective blindsight ,26,27. IThe behavioral and neurophysiological effects of the implicit processing of unseen fearful faces found in hemianopic patients without affective blindsight indicate that, when the visual cortex has been damaged or visual information cannot reach the visual cortex due to deafferentation, the only visual information available at the implicit level is related to fear. This implicit processing of fear information probably acts as a warning signal to enable rapid defensive responses.This finding seems in line with the hypothesized existence of pre-wired defensive survival circuits capable of responding to species-specific threats . These cAn undoubtedly integral component participating in these threat-detection systems is the amygdala, as suggested by its critical role in responding to fear ,31,32,33Importantly, the facilitatory effects observed in the presence of unaware fearful faces suggest that, when unconscious threat-related visual information reaches the amygdala, the consequent amygdala activation is capable of modulating connected sensory cortices, influencing sensory processing and, therefore, altering the gating of information processing. In other words, the activity of the amygdala in response to unaware threatening signals in the environment might be able to lower the threshold for detecting stimuli in the interconnected sensory cortices, facilitating the sensory analysis of the surroundings . In thisIn addition to evidence of responsiveness of the amygdala to a wide range of emotions ,57,58 anThis converging evidence therefore strengthens the notion that the amygdala is a crucial component in a system responding to ambiguous and relevant environmental stimuli (such as fearful faces). Interestingly, the aforementioned fear-specific, implicit processing observed in hemianopics seems to provide an indirect confirmation of this view. Indeed, the facilitatory effect of unseen fearful faces in hemianopics was evident only when the non-conscious, fear-related stimulus was presented in an ambiguous experimental condition . In contrast, no effect was observed when a congruent fearful face was displayed in the intact field ,20. In tAs a whole, these findings corroborate the existence of a continuous monitoring system, in which the amygdala can boost vigilance in response to uncertain events which might potentially signal the presence of a threat, in order to allocate spatial attention and modulate visual analysis and exploration .An intriguing finding concerning the previously mentioned implicit processing of fearful faces in patients with hemianopia was that the facilitatory effects of presenting fearful faces in the blind field were found only after lesions to the visual cortices in the left hemisphere. Indeed, both the behavioral facilitation in discriminating visual stimuli in the intact field ,19 and tIn line with this hypothesis, neuroimaging findings showed that significant neural responses were elicited in the right but not the left amygdala by unconscious fear-conditioned stimuli . SimilarMoreover, connections between the right amygdala and the structures participating in the subcortical emotional pathway  in the right hemisphere have been shown to play a key role in unconscious fear perception. Neuroimaging evidence showed that connectivity between the right amygdala, the pulvinar and the superior colliculus was increased by the presentation of masked fear-conditioned faces, while the connectivity between the left amygdala and the pulvinar, or the superior colliculus, did not discriminate between the presentation of seen or unseen fear-conditioned targets . MoreoveThe evidence reviewed in the previous paragraphs used patients with visual field defects and unilateral lesions to the primary visual cortices as a model to investigate implicit visual processing of emotional stimuli in the absence of awareness and the contribution of subcortical visual circuits to this phenomenon. The reported findings highlight that, after lesions to the primary visual pathway, fearful signals receive preferential implicit processing that can facilitate responses to visual stimuli presented in the intact visual field. This suggests the presence of an adaptive mechanism through which evolutionarily relevant visual information can be processed without awareness, promoting effective visual exploration of the environment to engage defensive responses to possible threats. Moreover, the colliculo-pulvinar-amygdala pathway in the right hemisphere seems to account for such fear-specific, implicit processing, since only hemianopics with lesions to the left-hemisphere  show these effects.The dominance of the right hemisphere in processing and responding to emotional stimuli has been theorized  baseHowever, the specific, implicit processing of unseen fearful stimuli observed only in hemianopics with left hemispheric lesions ,18,19,20Although further research is needed to corroborate and provide a conclusive interpretation of this right-hemisphere specialization for unconscious fear-related information, the pivotal contribution of the amygdala, which is an integral part of the subcortical emotional circuit, might help explain this fear-specific, implicit effect. Indeed, the amygdala is crucial for responding to ambiguous and uncertain salient environmental stimuli and plays a role in boosting vigilance, which might help lower activation thresholds throughout sensory cortices and deploy attention to the surroundings to search for potentially dangerous signals ,88. From