Editorial: Rising stars in avian physiology: 2022

Recognizing the future leaders of Avian Physiology is fundamental to safeguarding tomorrow’s driving force in innovation. This Research Topic is aimed to supporting scientists in the early stages of their careers across a wide range of disciplines by selecting and publishing their research output at the highest quality standards. In some sense, Avian Physiology is an amalgam of several fields and disciplines. This is reflected in the fact that veterinary oversight of animal research often distinguishes birds from poultry, birds that are used in agriculture. On one hand, avian physiologists who study poultry with the important objective of improving the health and profitability of poultry species are frequently called “poultry scientists”. Poultry scientists have their own journals, such as Poultry Science, and their own societies, such as the Poultry Science Association and others. On the other hand, avian physiologists who study basic mechanisms in a variety of avian species, including poultry species, are often called “ornithologists”. Ornithologists, like poultry scientists, have their own journals, such as Auk and Condor, as well as societies such as the International Ornithological Congress. And there are societies, such as the International Society for Avian Endocrinology, and journals, such as this journal, that address scientific issues from the breadth of Avian Physiology. This Research Topic reflects that breadth

The Bird of Time: Cognition and the Avian Biological Clock

Avian behavior and physiology are embedded in time at many levels of biological organization. Biological clock function in birds is critical for sleep/wake cycles, but may also regulate the acquisition of place memory, learning of song from tutors, social integration, and time-compensated navigation. This relationship has two major implications. First, mechanisms of the circadian clock should be linked in some way to the mechanisms of all these behaviors. How is not yet clear, and evidence that the central clock has effects is piecemeal. Second, selection acting on characters that are linked to the circadian clock should influence aspects of the clock mechanism itself. Little evidence exists for this in birds, but there have been few attempts to assess this idea. At its core, the avian circadian clock is a multi-oscillator system comprising the pineal gland, the retinae, and the avian homologs of the suprachiasmatic nuclei, whose mutual interactions ensure coordinated physiological functions, which are in turn synchronized to ambient light cycles (LD) via encephalic, pineal, and retinal photoreceptors. At the molecular level, avian biological clocks comprise a genetic network of positive elements clock and bmal1 whose interactions with the negative elements period 2 (per2), period 3 (per3), and the cryptochromes form an oscillatory feedback loop that circumnavigates the 24 h of the day. We assess the possibilities for dual integration of the clock with time-dependent cognitive processes. Closer examination of the molecular, physiological, and behavioral elements of the circadian system would place birds at a very interesting fulcrum in the neurobiology of time in learning, memory, and navigation

Fertility, Belief, and Sexuality

The human ovulatory cycle lasts an average of 28 days and is highly variable both within and among women, making ovulation and the fertile window difficult to estimate in humans. Commonly used methods for estimating fertility assume length consistency during various cycle phases, an assumption that often miscategorizes women as fertile when not and vice versa. This experiment analyzes several of the common methods used to estimate fertility, including forwards and backwards-counting methods and actuarial methods, and compares them against hormonal testing to determine the most accurate method for fertility identification. Additionally, we used hormonal ovulation tests combined with daily journaling reports to determine the degree to which fertility affects sexual desire, likely sexual engagement, and general happiness, as well as a woman’s belief that she is fertile. We hypothesize that women will not be able to accurately predict their fertility and will show increased sexual interest and general happiness during the fertile window. We also hypothesize that estimation methods will have different results than those using confirmed fertility, but that the closest estimation will be backward counting methods estimating fertility as the six-day window ending at thirteen days from the start of menses

A Low-Intensity, Hybrid Design Between a Traditional and a Course-Based Research Experience Yields Positive Outcomes for Science Undergraduate Freshmen and Shows Potential for Large-Scale Application

Based on positive student outcomes, providing research experiences from early undergraduate years is recommended for science, technology, engineering, and mathematics (STEM) majors. To this end, we designed a novel research experience called the “STEMCats Research Experience” (SRE) for a cohort of 119 second-semester freshmen with diverse college preparatory levels, demographics, and academic majors. The SRE targeted student outcomes of enhancing retention in STEM majors, STEM competency development, and STEM academic performance. It was designed as a hybrid of features from apprenticeship-based traditional undergraduate research experience and course-based undergraduate research experience designs, considering five factors: 1) an authentic research experience, 2) a supportive environment, 3) current and future needs for scale, 4) student characteristics and circumstances, and 5) availability and sustainability of institutional resources. Emerging concepts for facilitating and assessing student success and STEM curriculum effectiveness were integrated into the SRE design and outcomes evaluation. Here, we report the efficient and broadly applicable SRE design and, based on the analysis of institutional data and student perceptions, promising student outcomes from its first iteration. Potential improvements for the SRE design and future research directions are discussed

Diagnosis, Clinical Features and Management of Interstitial Lung Diseases in Rheumatic Disorders: Still a Long Journey

: Interstitial lung disease (ILD) is one of the most frequent pulmonary complications of autoimmune rheumatic diseases (ARDs), and it is mainly associated with connective tissue diseases (CTDs) and rheumatoid arthritis (RA) [...]

Toward the Beginning of Time: Circadian Rhythms in Metabolism Precede Rhythms in Clock Gene Expression in Mouse Embryonic Stem Cells

The appearance, progression, and potential role for circadian rhythms during early development have previously focused mainly on the suprachiasmatic nucleus (SCN) and peri- and postnatal expression of canonical clock genes. More recently, gene expression studies in embryonic stem cells have shown that some clock genes are expressed in undifferentiated cells; however rhythmicity was only established when cells are directed toward a neural fate. These studies also concluded that a functional clock is not present in ESCs, based solely on their gene expression. The null hypothesis underlying the present study is that embryonic stem cells become rhythmic in both clock gene expression and glucose utilization only when allowed to spontaneously differentiate. Undifferentiated stem cells (ESCs, n = 6 cultures/timepoint for all experiments) were either maintained in their pluripotent state or released into differentiation (dESCs, n = 6 cultures/timepoint for all experiments). Glucose utilization was assayed through 2-deoxyglucose uptake measurement, and clock gene and glucose transporter expression was assayed every 4 hours for 2 days in ESCs and dESCs by quantitative PCR (qPCR) in the same cell lysates. Undifferentiated stem cells expressed a self-sustained rhythm in glucose uptake that was not coincident with rhythmic expression of clock genes. This physiological rhythm was paralleled by glucose transporter mRNA expression. Upon differentiation, circadian patterns of some but not all clock genes were expressed, and the amplitude of the glucose utilization rhythm was enhanced in dESCs. These data provide the earliest evidence of a functional circadian clock, in addition to further challenging the idea that rhythmic transcription of clock genes are necessary for rhythmic physiological output and suggest a role for a clock-controlled physiology in the earliest stages of development

Heavy barbell hip thrusts do not effect sprint performance: an 8-week randomized–controlled study

The purpose of this study was to examine the effects of an 8-week barbell hip thrust strength training program on sprint performance. Twenty-one collegiate athletes (15 males and 6 females) were randomly assigned to either an intervention (n = 11, age 27.36 ± 3.17 years, height 169.55 ± 10.38 cm, weight 72.7± 18 kg) or control group (n = 10, age 27.2 ± 3.36 years, height 176.2 ± 7.94 cm, weight 76.39 ± 11.47 kg). 1RM hip thrust, 40m sprint time, and individual 10m split timings: 0-10, 10-20, 20-30, 30-40m, were the measured variables; these recorded at both the baseline and post testing time points. Following the 8-week hip thrust strength training intervention significantly greater 1RM hip thrust scores for the training group were observed (p 0.05, r = 0.05 – 0.37). No significant differences were seen for the control group for 1RM hip thrust (p = 0.106, d = 0.24 [mean difference 9.4 kg]) or sprint time (all sprint performance measures: p > 0.05, r = 0.13 – 0.47). These findings suggest that increasing maximum hip thrust strength through use of the barbell hip thrust does not appear to transfer into improvements in sprint performance in collegiate level athletes

Real-time polymerase chain reaction and laser capture microdissection: an efficient combination tool for Chlamydophila pneumoniae DNA quantification and localization of infection in atherosclerotic lesions.

Chlamydophila pneumoniae has been implicated in atherosclerosis, but the role of this obligate intracellular pathogen in the development of the above pathology is still unclear. In particular, its presence and quantitative distribution within lesional areas has not yet been defined. We studied 18 carotid biopsies obtained from patients undergoing endoartherectomy. By laser microdissection (LCM), two different sites (intra-plaque and plaque-adjacent areas) were taken from each lesion, and the presence and quantity of the pathogen DNA were determined by real-time polymerase chain reaction (Real-time PCR). A total of 8 plaques, exclusively, from patients with unstable angina, were positive in real-time PCR. The bacterial DNA was detected in both lesional areas of 3 plaques which contained the highest number of DNA copies (1,900 to 2,200 copy numbers), while C. pneumoniae DNA was detected only in the intra-plaque area of the other 5 positive (500 to 1,600 copy numbers). No C. pneumoniae DNA was found in the other 10 plaques of which 6 were from patients with unstable angina and 4 from stable angina patients. No DNA from Helicobacter pylori or Cytomegalovirus was found in any plaque. This is the first report where both the target lesion and an adjacent reference site were evaluated for the presence of C. pneumoniae DNA by the combination of LCM and Real-time PCR assays. The integration of these two methodologies offer an excellent tool for in situ studies and may help to elucidate the putative role of C. pneumoniae in atherosclerosis

Pirfenidone for the treatment of interstitial lung disease associated to rheumatoid arthritis: a new scenario is coming?

Introduction: Interstitial lung disease (ILD) is a frequent extra-articular manifestation of Rheumatoid arthritis (RA), but nowadays there are no randomized controlled clinical trials to support therapeutic guidelines. RA-ILD, especially with UIP pattern, shares some similarities with idiopathic pulmonary fibrosis, suggesting a possible role of antifibrotic therapy in these patients. To date, there are no published data supporting the use of pifenidone in RA-ILD. We describe for the first time two patients with a diagnosis of RA-ILD successfully treated with hydroxychloroquine and pirfenidone, without adverse events. Case presentation: Patient 1 and patient 2 were first diagnosed with IPF (UIP pattern at high-resolution computed tomography, no other signs or symptoms suggesting other forms of ILD, routine laboratory examinations and immunological texts negative). Patients started pirfenidone 2403 mg daily. Few months later, they referred to our multidisciplinary outpatient for arthritis. ACPA and RF were positive. A diagnosis of RA was performed and treatment with corticosteroids and hydroxychloroquine was started, in association with pirfenidone. In both cases we assessed the stabilization of articular and lung manifestations, without adverse events. Discussion: In absence of randomized controlled trials, the optimal treatment of RA-ILD has not been determined and remains challenging. When considering therapeutic options for RA-ILD, both pulmonary and extra-thoracic disease manifestations and degrees of activity should be assessed and taken into consideration. Future prospective research might change RA-ILD management, moving to a more personalized approach based on the identification of different phenotypes of the disease or to a combination of immunosuppressive and antifibrotic treatment

The Premammillary Nucleus of the Hypothalamus Is Not Necessary for Photoperiodic Timekeeping in Female Turkeys (\u3cem\u3eMeleagris gallopavo\u3c/em\u3e)

In birds, seasonal reproduction is regulated by day length, with long days in the spring activating the hypothalamic-pituitary-gonadal axis and reproductive behaviors. The photoreceptors mediating this process remain unknown, but recently, the premammillary nucleus (PMM) of the hypothalamus has been implicated as the site of photoperiodic signaling in turkeys. We performed electrolytic lesions of the PMM to elucidate its role in the photoactivation and maintenance of egg production in female turkeys. Our results show that ablation of the PMM does not alter the normal lay cycle. No differences were found between lesioned birds and sham controls in the latency to lay following photostimulation, nor in subsequent egg production over a period of 29 weeks. No differences in the incidence of gonadal regression were found, indicating that the PMM is not essential for the termination of breeding. We conclude that any role of the PMM in photoperiodic regulation, if it exists, is redundant with other components of the system