bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationship between cardiac output via acetylene rebreathing and echocardiography in heart failure
Authors: McCue Meghan Cameron , Olson Thomas P , Johnson Bruce D , Snyder Eric M , Borlaug Barry A
Published: June 2021

Our lab has demonstrated a lower cardiac output (Q) in patients with heart failure (HF) vs. controls (CTL) using acetylene rebreathing (ACET). This technique may be dependent on lung health, which is altered in HF. Therefore, we examined the relationship between Q from echocardiography (echo) and Q from ACET at rest and during exercise. Additionally, we examined the relationship between stroke volume (SV) estimated from O2 pulse compared to SV by ACET (SVA). 26 controls (CTL) and 18 HF patients with preserved ejection fraction (EF) completed an exercise test on a cycle ergometer. Lung conductance was measured by lung diffusion for carbon monoxide (DLCO). Measures of Q (QA, Acetylene rebreathe; QE, transthoracic echo), heart rate (HR, 12‐lead ECG), and oxygen consumption (VO2, metabolic cart) were taken at rest and peak exercise. Stroke volume (SV) and O2 pulse were calculated as Q/HR and VO2/HR, respectively. HF patients had lower DLCO compared to CTL (Rest: DLCO=11±0.5 vs 14±0.6 ml/min/mmHg, p<0.05). At rest and exercise, QE was moderately correlated with QA in CTL (Rest: r=0.47; Pk Ex: r=0.51, p<0.05) and HF (rest: r=0.47; Pk Ex: r=0.77, p<0.05). O2 pulse was significantly related to SVA at rest and exercise in CTL (Rest: r=0.76; Pk Ex: r=0.81, p<0.05) and HF (Rest: r=0.81; Pk Ex: r=0.82, p<0.05). Cardiac function assessed via ACET is related to cardiac function by echo and O2 pulse in patients with HF with preserved EF.
Influence of exercise during 28 days of bed rest with energy deficit and amino acid supplementation on metabolic profile
Authors: Brooks Naomi Elisabeth , Cadena Samuel M , Cloutier Gregory , Vega‐López Sonia , Roubenoff Ronenn , Castaneda‐Sceppa Carmen
Published: June 2021

Muscle loss and metabolic changes occur with disuse [i.e. bed rest (BR)]. We investigated the metabolic profile after 28 days of BR with energy deficit in individuals randomized to resistance exercise with amino acid supplementation (RT, n=24) or amino acid supplementation alone (AA, n=7). We hypothesized that BR would lead to a metabolically unhealthy profile defined by: increased circulating tumor necrosis factor (TNF)‐α, decreased circulating insulin‐like‐growth‐factor (IGF)‐1, decreased HDL‐cholesterol, decreased normal density muscle (NDM) and increased low density muscle (LDM; measured by mid‐thigh computerized tomography). We found a shift toward a metabolically unhealthy profile after BR (compared to baseline) in both groups as shown by decreased HDL levels (AA: 39±4 →32±2 mg/dL, RT: 39±1 →32±1 mg/dL; p<0.001) and LDM (AA: 27±4 →22±3 cm2, RT: 28±2 → 23±2 cm2; p<0.001). A healthier metabolic profile was maintained with exercise, including NDM (AA: 124±6 → 110±5 cm2, RT: 132±3 → 131±4 cm2; p<0.001, time‐by‐group); although, exercise did not completely alleviate the unfavourable metabolic changes seen with BR. Interestingly, both groups had increased plasma IGF‐1 levels (AA: 168±22 → 213±20ng/mL, RT: 180±10 → 219±13 ng/mL; p<0.001) and neither group showed TNFα changes (p>;0.05). We conclude that RT can partially offset the metabolic complications of BR. Support: NSBRI‐NPFR00301 & GCRC M01 RR00
Energy cost of scuba underwater breathing apparatus on ventilation
Authors: Duvallet Alain , Duvallet Emilie , Lhuissier François , Beaudry Michele
Published: June 2021

Intervention in the subaquatic environment was made possible by the self‐contained breathing apparatus (scuba), which allows breathing in aquatic environment. However, this apparatus imposes to the respiratory function new constraints and a mechanical work. To study the energy cost imposed by the breathing on SCUBA we measured the oxygen consumption at rest with or without regulator in 3 populations, junior scuba‐diver (n=22), adult scuba‐diver (n=10) and non‐scuba‐diving adults (n=10).

The oxygen consumption increases from 241.3 to 414.8 ml O2/min or from 4.8kJ to 8.3kJ (delta=3.65 kJ). The variation observed between with or without the regulator is significantly different (paired t test, p= 0.0246). The oxygen consumption is significantly increased for the 3 populations studied.

It is accompanied by an increase of the VCO2, of the Vt and of the ventilation (6.89 l/min versus 9.2 l/min, delta = 2.31 l/min, p<0.0001). As well, we show a decrease of the respiratory rate.

The mechanical constraints due to SCUBA lead to a significant increase of the respiratory work with modification of the ventilator parameters. These variations are identical for the children (from 7 to 13 years) and for adults, in divers and in non‐divers.
Airway smooth muscle resolidification after stretch, but not static contractile force, is dependent on zyxin
Authors: Rosner Sonia Rebecca , Smith Mark , Blankman Elizabeth , Jensen Chris , Krishnan Ramaswamy , Beckerle Mary C , Fredberg Jeffrey J
Published: June 2021

This study examines the role of zyxin, a cytoskeletal regulatory protein, in the mechanics of airway smooth muscle (ASM) under both static and dynamic conditions. Primary tracheal ASM cells from WT and zyxin−/− mice were obtained and baseline contractile force and changes in contractile force before and after a series of 3 transient isotropic stretches (5–10% strain) were measured in single cells using Fourier transform traction microscopy. Additional contractile force measurements as well as other cell mechanics measurements were performed on zyxin−/− and GFP‐zyxin rescued murine embryonic fibroblasts (MEFs). Zyxin−/− primary ASM fail to resolidify to the same extent as the WT primary ASM following single transient stretches as well as a series of transient stretches, although there is no difference in their baseline contractility. Similar results were found in MEFs; additionally baseline cytoskeletal stiffness was found to be the same in zyxin−/− and GFP‐zyxin rescued MEFs. Based on these results, resolidification following transient stretch appears to be dependent on the presence of zyxin in ASM cells. This indicates that zyxin may be a potential target for modulating the contractile dynamics of ASM during bronchospasm in the dynamic mechanical environment of the asthmatic lung.
N‐cadherin contributes to the pulmonary microvascular endothelial response to LPS
Authors: Jian Ming‐Yuan , Creighton Judy
Published: June 2021

Lipopolysaccharide (LPS) is known to damage the lung's microcirculation resulting in loss of endothelial barrier integrity and increased edema. We have shown previously that AMPK activation resolves this injury. In lung pulmonary microvascular cells (PMVECs), AMPKα1 localizes to a discreet membrane compartment with N‐cadherin leading us to hypothesize that N‐cadherin was involved in the PMVEC response to LPS. Inhibition of N‐cadherin using a blocking antibody impaired endothelial formation of a tight pulmonary microvascular barrier and delayed monolayer resealing. This effect was exacerbated in the presence of LPS. Wounded control monolayers resealed at a velocity of 6 μm/sec, whereas LPS reduced the resealing rate to 4 μm/sec. In PMVECs expressing shRNA to N‐cadherin (ΔN‐cad), which reduced N‐cadherin content by 80%, the resealing rate in the presence of LPS was 2 μm/sec. Moreover, the ΔN‐cad cells were 4 fold more sensitive to LPS‐induced injury. These data provide evidence that N‐cadherin and AMPK work in tandem in the PMVEC response to LPS‐induced endothelial injury. Supported by HL102296 and HL 110803.
MCF‐7 breast cancer cell internal pH regulation
Authors: Papineau Alyssa , Runge Steven , Washington Tyrone , Naylor Kari , Horton Leah
Published: June 2021

Tumors create an extracellular pH (pHe) barrier and form an isolated microenvironment roughly 0.5 pH units lower than physiological pH, while the intracellular pH (pHi) is maintained within 0.2 pH units of physiological levels. Reduced tumor pHi is associated with apoptosis, and lowered arterial and tissue pH are seen with heavy exercise.

PURPOSE

To determine the pHi response of MCF‐7 cells subjected to acidic environments. MCF‐7 cells loaded with BCECF, a pH indicator, were used to create a standard curve of fluorescent ratios at six pH levels. MCF‐7 cells were then subjected to pHe levels of 6.75 and 6.25 at 0, 15, 30, 45, 60, 120, 180, and 1,440 minutes of pHe exposure. Data were referenced to MCF‐7 cells at a physiological pHe of 7.25. A treatment effect was seen at pHe 6.25 (p = 0.0002). Compared to the control, cells subjected to pHe 6.25 for 15, 30, 45, and 1,440 minutes had lower pHi levels (p = 0.0464, p = 0.0002, p = 0.0257, and p = 0.0054, respectively). An interaction of pHe and time (p = 0.0483) on pHi was observed. The pHi values were lower at pHe 6.25 than at pHe 6.75 after 30, 180, and 1,440 minutes of exposure (p = 0.0193, p = 0.0200, and p < 0.0001, respectively). In conclusion, MCF‐7 cells subjected to a pHe of 6.75 maintained their pHi, but a different recovery response was seen at pHe 6.25. A decreased tolerance of lower pH levels may provide a mechanism by which heavy exercise would prove beneficial for breast cancer patients.
Renal Lipid Accumulation in Human Obesity
Authors: Bobulescu Ion Alexandru , Rosenthal Tara , Thompson Hillary , Sakhaee Khashayar , Moe Orson W
Published: June 2021

In obesity and the metabolic syndrome, lipid accumulation in several non‐adipose tissues has been implicated in the pathogenesis of tissue and organ dysfunction. Whether obesity is associated with lipid accumulation in the human kidney remains uncertain. To address this uncertainty, we obtained kidney cortex samples from patients with a wide range of body mass indexes (BMI) undergoing nephrectomy for renal cell carcinoma. Only normal cortex samples were used, with pathologist confirmation of normal morphology and significant separation from any cancerous tissue (N=52). The samples were used for histology (including Oil Red O lipid staining), biochemical measurement of triglyceride content, and in subsets of samples sphingolipid profiling by liquid chromatography‐mass spectrometry and RNA extraction followed by Illumina gene expression array analysis and real‐time RT‐PCR. We found a positive correlation between renal cortical triglyceride content and patient BMI (R=0.426). Higher renal triglyceride content was associated with significant upregulation of more than 20 genes involved in fatty acid transport, lipid metabolism and oxidative stress response in the kidney. These findings are compatible with the hypothesis that renal lipid accumulation contributes to the pathogenesis of obesity‐associated renal disease.
Predicting the course of the marginal mandibular nerve: an evaluation of surgical landmarks
Authors: Davies Joel C , Fattah Adel , Ravichandiran Mayo , Agur Anne
Published: June 2021

The inferior branch of the marginal mandibular nerve (IMB) is at risk of injury during surgical neck dissections due to its variability. Often surgeons rely on a two‐finger breadth, and/or 2cm distance below the inferior border of the mandible for submandibular incision placement (Witt, 2006). The purpose was to evaluate the accuracy of the landmarks and to define other fixed landmarks to avoid IMB injury. In ten Thiel embalmed specimens, six independent raters palpated/pinned the inferior border of the mandible and a line two‐finger breadths below. Each pinhead was digitized (Microscribe®) and a superficial musculoaponeurotic (SMAS) flap was raised using a Ridson approach. The IMB was identified and digitized from the parotid gland to the depressor anguli oris/labii inferioris. The digitized data were modeled (Autodesk Maya®) and distances between the IMB and landmarks quantified. The distance from the IMB to the inferior border of the mandible varied from 2.5–11.5mm (7.5±2.9) suggesting that in some cases the 2cm landmark may be risky. The two‐finger breadth line to the IMB was 18.9–38.2mm (30.6±7.2) indicating adequate clearance for the nerve. Other landmarks have been documented. To avoid injury of the IMB during surgical neck dissections, easily measurable and reliable bony landmarks should be identified which can accurately predict the course and distribution of the nerve.
Ultrastructure of the sciatic nerve in diabetic rats.
Authors: Vasconcelos Carlos Augusto Carvalho , Fazan Valéria Paula Sassoli , Filho José Luiz Lima , Brayner Fábio , Alves Luiz Carlos , Nessler Randy Alan , Valença Marcelo Moraes
Published: June 2021

Animal models of diabetes have been widely used in experimental studies because they offer promise of new insights into human diabetes. Streptozotocin (STZ)–treated rats are an animal model of insulin‐dependent diabetes mellitus commonly used to study peripheral nervous system alterations even though the changes do not fully match the alterations observed in clinical conditions. Nevertheless, animal studies can be informative as to the changes that develop in the early stages of human diabetes. Male Wistar rats (n = 12) at 42 days of age were used. Induced diabetic animals (n=6) were fasted for 12 hours prior to being injected intraperitoneally with STZ (60mg/kg) in a single dose. Control animals (n=6) received vehicle. Ten weeks after STZ injection the animals were perfused intracardially with Karnovsky solution. Right and left sciatic nerves were dissected and processed for epoxy resin embedding. Samples were imaged with a transmission electron microscope. Large myelinated fibers with morphological signs of axonal atrophy in the sciatic nerves were readily observed. We also showed smaller myelinated fibers with sighs of demyelination. These results suggest that chronic STZ‐induced diabetes in rats caused alterations in the myelinated fibers as well as in the Schwann cells, compatible to the classic diabetes signs and symptoms reported in humans.

Support: PNPD/CAPES; FAPESP; CNPq
The effect of Vitamin C on amodiaquine‐induced oxidative stress in the ovary of Sprague‐Dawley rats
Authors: Gbotolorun Stella C , Osinubi Abraham A , Oremosu Ademola A , Noronha Cressie C , Akpantah Amabe o , Coker Herbert AB , Silva Boladale O
Published: June 2021

AQ‐induced oxidative stress leads to increased atresia which in turn leads to reduced follicle numbers, and reduced oocyte numbers at ovulation. This research study the effect of the co‐administration of amodiaquine hydrochloride (AQ.HCl) with Vitamin C on oestrous cycle, ovulation, oxidative stress markers and the histomorphology of the ovary of mature Sprague‐Dawley rats.

Two study experimental groups were observed, Group 1: the effect of the co‐administration of AQ.HCl with Vitamin C on pattern and length of the oestrous cycle, histomorphology of the ovary and antioxidant activities of superoxide dismutase (SOD) and catalase (CAT). Group 2: the effect of the co‐administration of a single dose of AQ.HCl with Vitamin C administered in the evening of proestrus on ovulation and serum concentrations of follicle stimulating hormone (FSH), luteinizing hormone (LH) and prolactin (PRL).

Co‐administration of AQ.HCl with Vitamin C resulted in an irregularity in cycle pattern and also increased (p < 0.05) the length of the oestrous cycle by prolonging the diestrus phase compared to the control. Histological sections showed increased number of atretic follicles compared to the control. A statistical significant decrease (p < 0.05) was observed in the activities of CAT and SOD. Serum levels of FSH, LH and PRL were comparable to control values however; the number of ova shed in the oviduct was significantly reduced (p < 0.05). The result of this study showed that Vitamin C could not confer protection against the deleterious effect of AQ.HCl on the ovary of Sprague‐Dawley rats.
Cross‐sectional geometry of chimpanzee (Pan troglodytes) finger bones is correlated with habitual load bearing of individual digits during knuckle‐walking
Authors: Patel Biren A. , Wallace Ian J.
Published: June 2021

Chimpanzee finger bones sustain large mechanical loads during knuckle‐walking on the ground. Digital flexors are not recruited to moderate these loads during weight support. Pressure data indicate that loads sustained by fingers are not evenly distributed across digits. Higher pressures are experienced by digits II and III than by digit V. Because bone tissue can adjust to its functional environment such that its morphology is “optimized” according to mechanical demand, the load variation implied by pressure data should have a predictable effect on the relative robusticity of finger bones, i.e. the bones of digits II/III should be more robust than those of digit V. Also, knuckle‐walking postures engenders larger bending moments in obliquely oriented proximal phalanges than in horizontally oriented middle phalanges, which should lead to relatively greater robusticity of proximal elements. Here, we measured the midshaft cross‐sectional geometry of phalanges from digits II‐V in 20 wild‐shot, adult chimpanzees using μCT. As predicted, we found that cortical bone area (scaled to body mass) and polar moment of area (scaled to body mass × bone length) are consistently larger in (1) phalanges from digits II and III than from digit V, and (2) proximal versus middle phalanges from the same digit. These results provide support for the idea that diaphyseal bone morphology reflects, at least to some extent, habitual behavior.

Grant Funding Source: N/A
Uncommon course of obturator nerve through an osseus tunnel: Clinical relevance
Authors: Vasan Cheryl , Varricchio Paolo , Pinhal‐Enfield Grace , Vasan Nagaswami
Published: June 2021

A unilateral variation in the course of the left obturator nerve was observed during cadaveric dissection of the pelvis and lumbar plexus. The donor was a 94‐year‐old Caucasian male died of renal and respiratory failure. Typically, obturator nerve arose from the ventral rami of lumbar spinal segments 2–4 and traveled forwards along the lesser pelvic lateral wall on the obturator internus to the obturator foramen. The variant obturator nerve descended normally anterior to sacroiliac junction continued the lateral pelvic course and entered a 6 cm long osseus tunnel in the superior rami beginning at the iliopectineal junction (close to ischial spine) and emerged to continue a normal course joined by the obturator vessels. The right side exhibited normal course. Although the course of the obturator nerve is often consistent, variations in pelvic vascular and nervous structures do exist, and clinicians should be aware of the possibility of encountering less common presentations of the obturator nerve. Knowledge of alternative course of obturator nerve has a significant impact during pelvic surgery, addressing pelvic fractures resulting from trauma or osteoporosis and approaches to regional anesthesia. This is the first report on the uncommon course of obturator nerve through an independent osseus tunnel in the pelvic bone. Its clinical relevance in surgery or trauma related to pelvic bone will be discussed.
Clinical Significance of Pathophysiology in Piriformis Syndrome Due to Multiple Variations in the Deep Gluteal Region
Authors: Vilaró José , Duarte Jhonathan , Veras Wilson R
Published: June 2021

A relationship between the piriformis muscle and the sciatic nerve, which is observed to be unusual has been suggested to be a cause of piriformis syndrome. During dissection of a male cadaver, several anatomical variations were encountered. These variations consist of atypical organization of the sacral plexus, unusual origins, trajectories of common fibular, tibial, and inferior gluteal nerves. It is also observed that the presence of a common tendon formed by the deep gluteal muscles (obturator internus, superior gemellus, inferior gemellus, and both piriformis muscles, a duplication of the piriformis muscle) inserts on the greater trochanter of the femur. Additionally, an early division of the sciatic nerve, where a common fibular nerve that runs between the two variant piriformis muscles, and the tibial nerve which is making its way below the inferior piriformis, is also observed. These anatomical variations are found to be bilateral. In these casses the unusual pathway of this sciatic nerve and its relationship with the piriformis may predispose to its impingement at the gluteal region. The prevalence of the piriformis and the sciatic nerve anomalies is 16.2% in surgical cases. Thus, clinicians and surgeons should be aware of the potential complications from these unique variations.
Age‐Related Difference in Postural Control During Recovery from Forward and Backward Falls
Authors: Singer Madeline Louise , Smith Lorinda K , Dibble Leland E. , Foreman K. Bo
Published: June 2021

Decreased reactive postural responses in elderly adults may place them at increased risk for falls and related injuries (30–40% of adults over 65 fall each year). To determine age‐related differences in reactive postural responses, we utilized the tether‐release method to evaluate kinematic variables in healthy young (n=10, mean age=25.4±5.34) and healthy elderly subjects (n=10, mean age=66.8±6.29). All subjects were instrumented and data were collected in a motion analysis lab during recovery from anterior and posterior perturbations. Kinematic dependent variables included reaction time, step length, step time, peak center of mass (COM) velocity, and recovery time. Each subject's first 3 successful trials were averaged and compared between groups using separate Mann‐Whitney U Tests (p≤0.01). No differences were found between groups for recovery from anterior perturbations. However, during posterior perturbations, healthy elderly subjects exhibited shorter step length (p=.006), slower peak COM velocity (p=.01), and longer recovery time (p=.01) compared to young subjects. These results suggest that slowness of movement, coupled with prolonged recovery time, may impair the ability of elderly adults to regain stability after posterior perturbations. Further examination of kinematic and kinetic variables is important to determine specific deficiencies contributing to falls in the elderly.

Grant Funding Source: University of Utah College of Health
Origin of suprascapular and lateral pectoral nerves from the brachial plexus: surgical vs anatomical findings
Authors: Li Zhi , Arad Ehud , Clarke Howard M. , Agur Anne M.
Published: June 2021

Most frequently the suprascapular nerve (SSN) is described as originating from the superior trunk (ST), and the lateral pectoral nerve (LPN) from the lateral cord (LC). However, during brachial plexus (BP) neurotization surgery the SSN and LPN are commonly observed to originate from the divisions. The purpose of this study is to define the origin of SSN and LPN. The BP was exposed with 3.5× loupe magnification, as used during surgery, in 10 Thiel and 20 formalin‐embalmed specimens. The origins of the SSN and LPN were documented; the BP was digitized and the data modeled in Autodesk MAYA®. The models were used to visualize and quantify the origins of SSN and LPN. The SSN originated from: (1) posterior division of ST 63.4%; (2) point of bifurcation of ST into divisions 23.3%; (3) C5 root 13.3%. Distance from the origin of SSN to bifurcation of ST ranges from 0 – 16mm. All 30 LPNs originated proximal to the LC, arising from: (1) middle trunk (MT) and anterior division of ST 86.6%; (2) anterior division of ST 13.3%; (3) MT 3.4%. Distance from the origin of LPN to the formation of LC ranges from 6 – 43mm. As observed in surgery, the origin of the SSN is more distal than defined in the literature, and the LPN more proximal. This may be due to maintenance of epineural integrity during surgery but not in traditional studies where nerves may appear to originate more distally or proximally. Renewed study of BP with attention to epineural integrity is needed.
Morphological and morphometric parameters of sural nerves of Wistar rats are not gender during development.
Authors: Carmo Elisabete Cássia , Sanada Luciana Sayuri , Machado Nathália Leilane Berrto , Nessler Randy Alan , Fazan Valéria Paula Sassoli
Published: June 2021

It is known that gender influences the re‐myelination, pain sensibilization, neural regulation of the vascular function, in vitro axonal growth and the conduction velocity of nerves. However, little is known about the influence of gender on peripheral nerves development. Previous studies from our laboratory described the development of the sural nerves in female rats [1] and concluded that at 180‐days of life the sural nerves are fully developed. We compared the morphological and morphometric aspects of different segments of the sural nerves in male (N=6) and female (N=6) adult (180 days of life) Wistar rats. The animals were anesthetized, perfused and the right and left sural nerves were removed and prepared for epoxy resin embedding and light microscopy. Morphometric analysis was performed with the aid of computer software, and took into consideration the fascicle area and diameter, as well as myelinated fiber number, density, area and diameter. Comparisons between segments and sides were performed and significant differences were considered when p<0.05. The results showed that adult males are larger and heavier than the females. Nevertheless, there were no significant differences between genders, when the sural nerve fascicular parameters were compared. Thus, the morphological and morphometric parameters of sural nerve are not gender related.
The Effect of Exercise on the histological analysis in the Shoulder joint of the Aging rat
Authors: Murata Kenji , Kanemura Naohiko , Kokubun Takanori , Fujino Tsutomu , Takayanagi Kiyomi
Published: June 2021

Objective

Tendinopathy is a common clinical problem at the shoulder joint. Aging leads to the degeneration the supraspinatus tendon, On the other hand, the exercise is vital to the tendon remodeling. In this present study, we observed the effect of periodic exercise using supraspinatus tendon of aged rat.

Methods

We studied 2‐years‐old male Wister rats were used (n=5), and they were divided into Exercise group (n=4) and Control group (n=1). Exercise group underwent an exercise protocol cosisting of an hour per daily session of treadmill running exercise at a speed of 5.8m/min, 5 days a week for a month. After the experimental periods, sections were cut at 20 μm (frontal plane), and supraspinatus tendon and enthesis were evaluated with histological analysis (Truijin‐blue staining).

Result

Our results showed that the enthesis degeneration change in the control group compared with the exercise. Furthermore, in the supraspinatus tendon, fiber statue was confirmed in the exercise group, however, in the control group it was difficult to.

Conclusion

These conditions may suggest that the exercise is one of the remodeling factor for shoulder degeneration, tendenopathy.
Isolation and Characterization of Enteric Nervous System Stem Cells
Authors: Hotta Ryo , Carreon‐Rodriguez Alfonso , Belkind‐Gerson Jaime , Goldstein Allan M
Published: June 2021

Purpose

Enteric nervous system (ENS) stem cells are present in embryonic and postnatal gut. Isolation of these cells would be valuable for treating a deficient or injured ENS. We aimed to study the effect of glial‐derived neurotrophic factor (GDNF) on growth and differentiation of ENS stem cells.

Materials & Methods

Embryonic rat intestine was digested and the cells grown in medium supplemented with EGF and bFGF. Neurosphere‐like bodies developed, dispersed, and plated in a collagen matrix at clonal density. These cultures were supplemented with EGF and bFGF, with and without GDNF (10 or 50 ng/ml). Colony number and size was recorded and their capacity to form new neurospheres tested.

Results

While control cultures developed colonies <0.5 mm in size, colonies in GDNF‐treated cultures were larger (>;2 mm). Secondary colonies arose from 0.04–0.4% of these cells, forming new neurospheres with neuroglial morphology.

Conclusions

Our results demonstrate that neurosphere‐like bodies derived from rat embryonic gut are capable of self‐propagation and neuroglial differentiation, consistent with stem/progenitor cell behavior. In addition, we find that GDNF stimulates ENS stem cell proliferation to form large colonies that maintain the potential to differentiate into neural and glial phenotypes. This work was partially supported by a grant from CONACYT.
Effects of dietary supplementation with fish oil on cutaneous wound healing of stressed mice
Authors: Souza Bruna Romana , dos Santos Rosa Alice , Bandeira Luana Gabriela , Monte‐Alto‐Costa Andrea
Published: June 2021

Neither study demonstrated if supplementation with fish oil could inhibit stress effects on cutaneous wound healing. Thus, the aim of this study was to investigate effect of fish oil supplementation on cutaneous wound healing of chronically stressed mice. Adult male mice (n=10 per group) were daily spun at 115 rpm for 15 minutes every hour until euthanasia. Other animals were not submitted to stress. Fish oil administration began one day before wounding and was continued daily until euthanasia. A full‐thickness excisional lesion was performed. Fourteen days later, animals were killed and lesions were collected. This study was approved by the Ethical Commission in the Research of the Federal Rural University of Rio de Janeiro (n°095/2010). Fish oil administration did not inhibit stress‐induced reduction in wound contraction and hydroxyproline levels. Stress‐induced increase in F4/80‐positive macrophage, MPO‐positive neutrophil number, and α‐SMA‐positive myofibroblast density was not reversed by fish oil. However, fish oil administration reversed stress‐induced increase in catecholamine and PGE2 levels. In conclusion, although supplementation with fish oil reversed the effects of stress on catecholamine and PGE2 synthesis it did not improve cutaneous wound healing of stressed mice. This study was supported by the Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ).
AN ANATOMICAL REVIEW OF THE MEDICO‐LEGAL ASPECTS OF THE HISTORIC RUXTON CRIMINAL CASE
Authors: Nusse Gloria Louise
Published: June 2021

On the 29th of September in 1935, human remains were discovered in the small Scotland town of Moffat. Thus began a case that has impacted the study of forensic science ever since. The use of anatomy and human dissection skills were instrumental in solving this crime. The reassembly of the bodies and the presentation in court of the anatomical findings provide a fascinating and historic look of the early criminalistic use of anatomy, forensic science and physical anthropology. This presentation will contain images from the 1937 book by John Glaister and James Brash, Medico Legal Aspects of the Ruxton Case, as well as other findings. This presentation will offer the listener a greater understanding of the historical heritage of anatomy in forensic science.
Mapping DNA replication origins in the human genome
Authors: Gerbi Susan A. , Urban John , Foulk Michael
Published: June 2021

We will present our results using nascent strand sequencing (NS‐Seq) to map DNA replication origins in the human genome. Nascent DNA strands were isolated from MCF7 and MCF10A cells to allow comparisons between breast cancer and normal genomes. NS‐Seq employs lambda exonuclease (Lexo) to destroy parental DNA; newly replicating DNA has an RNA primer at its 5′ end, rendering it resistant to Lexo digestion. We will compare our results to those of others and discuss the methodological and computational factors leading to the large discrepancy between their data sets. Our goal is to resolve the confusion in the field on the number and identity of replication origins. The fractionated size of the nascent strand sample is important to avoid contamination from Okazaki fragments. Also, non‐replicating input DNA used as a control is important. Variables in the computational analysis will be discussed. We have analyzed whether DNA replication origins display a base composition bias, the average spacing between replication origins, how many origins map to intergenic regions as compared to within genes and association of origins with the estrogen receptor.

(Supported by DOD Breast Cancer Program W81XWH‐10–1‐0463)
The P‐TEFb‐dependent Gene Coding for IL‐1β is More Sensitive to Cellular Metabolism than that of the BRD4‐dependent TNFα‐coding Gene
Authors: Adamik Juraj , Tannahill Gillian M. , Su An‐Jey A , O'Neill Luke A , Galson Deborah L , Auron Philip E.
Published: June 2021

The induction of the immediate‐early genes coding for Interleukin 1β (IL‐1β) and Tumor Necrosis Factor α (TNFα) is dependent upon Toll‐Like receptor 4 (TLR4) detection of bacterial lipopolysaccharide (LPS). We have observed various distinctions for these genes that correlate with RNA Polymerase II (Pol II) pausing, specific transcription factor involvement, promoter architecture and histone epigenetics. In contrast to human TNF, which possesses paused Pol II, human IL1B requires lineage‐specific Spi‐1/PU.1 as an anchor for induction‐dependent interaction with C/EBPβ and NF‐κB, resulting in rapid LPS‐dependent de novo recruitment of TBP and Pol II in concert with a permissive state for elongation mediated by the rapid recruitment of elongation factor P‐TEFb. In contrast, we observed that LPS‐inducible binding of NF‐κB to TNF facilitates immediate recruitment of BRD4. Treatment of murine macrophages with the metabolic inhibitor 2‐deoxyglucose reduced Pol II levels at the Il1b gene, while Tnf remained unaffected. P‐TEFb recruitment, Pol II serine 2 phosphorylation and histone H3K36me3 modification were reduced more significantly on Il1b than Tnf. A similar effect is observed in the presence of a PI3‐kinase inhibitor. Consequently, IL‐1β gene transcription is both more sensitive to the metabolic state of the cell and a dependence upon P‐TEFb than the gene coding for TNFα.
NPM new interacting partners and influence of NPM mutations on gene regulation
Authors: Zmiri Farah Ahlam , Fotouhi‐Ardakani Nasser , Éric Milot
Published: June 2021

Nucleophosmin (NPM) is a multifunctional protein. NPM mutation is found in one third of all acute myeloid leukemia (AML), and in more than 60% of AML with normal karyotype. It is also a recurrent translocation partner in AML.

We got interested in the NPM function as a co‐regulator of gene expression. We hypothesized that the modifications of NPM disrupt gene regulation and thereby, favour leukemia.

With a combination of biochemistry and molecular biology techniques, we identified new partners of NPM involved in gene regulation. We found that NPM colocalise with different transcription regulators at specific genes. Based on our results, we propose that the effect of NPM modifications on gene regulation has a significant impact on the capacity of hematopoietic cells to receive extra‐cellular signals which favours abnormal hematopoiesis and potentially, leukemia.
Gripp‐Heel and the Antiviral Host‐Cell Responses against Adenovirus
Authors: Moyler Candace , Wolf Dana W. , Oberbaum M. , Dorozko M. , Ives John A. , Muhie Seid , Miller Stacy A. , Jonas Wayne B. , Jett Marti , Hammamieh Rasha
Published: June 2021

Adenoviruses cause respiratory and ocular infections as well as pneumonia outbreaks in military recruits. The adenoviral infection is known to trigger a vigorous host innate response with the induction of acute inflammation, possibly playing a role in antiviral defense, but also contributes to the pathogenesis and clinical severity of invasive adenoviral infections. The cellular innate response signaling cascades and inflammatory cytokines production is induced early upon viral entry, by activation of innate danger‐sensing cellular receptors, including Toll‐like receptors (TLRs), Nod‐like receptors, and RIG‐like receptors (RLRs). Although the signals for the proinflammatory effector molecule production remain mostly unknown, one of the key components of the innate immune response are shown to be induced by adenovirus is the NLRP3 inflammasome. To date, cidofovir is the only antiviral drug employed for the treatment of severe adenovirus infection; however its use is limited by toxicity, low oral bioavailability, and variable efficacy. In this study we evaluated the in vitro antiviral activity of Gripp‐Heel against adenovirus, and further analyzed the effect of Gripp‐Heel on cellular gene transcription in an attempt to address its mechanism of action and impact on the host response.

The views, opinions, and/or findings contained in this report are those of the authors and should not be construed as official Department of the Army position, policy, or decision, unless designated by other official documentation
Pre‐Clinical Vaccination of BALB/c Mice with Five Novel Vaccines Against a Murine Hookworm Model
Authors: Comella Phillip Hunter
Published: June 2021

Hookworm infects approximately 600 million people worldwide. Our laboratory is investigating regions of a secreted parasitic protein as a vaccine against hookworm. This project demonstrates a pre‐clinical trial examining the safety, tolerability and efficacy of five novel peptide vaccines. Peptide design relied heavily on bioinformatic analysis of protein conservation across human‐parasitizing species of hookworm, as well as antigenicity, hydrophilicity and flexibility of potential peptide sequences. Each vaccine was administered to seven age and sex‐matched Balb/c mice, followed by two boosts, with serum samples collected on immunization days. Parasite challenge infections were administered 14 days after the last boost and efficacy was assessed based on subsequent adult worm burden levels. Highly statistically significant protection was achieved with one of the vaccines. In conclusion, we demonstrate the testing of five unique vaccines against hookworm and detail the findings of an anti‐hookworm vaccine exhibiting pre‐clinical protection against this debilitating disease.
Determining the Ability of Various Chelators to Stabilize a Reducing Environment via a Microtiter Plate Method
Authors: Lang Ewa , Hershberger Stefan , Vaidya Shyam , Rupprecht Kevin , Fishpaugh Jeffrey
Published: June 2021

The conformational stability of proteins can be impacted by the oxidation/reduction (Redox) of disulfide bonds. Redox sensitivity is often more pronounced for proteins that are coated onto a magnetic particle solid support due to the increased presence of heavy metal ions. In the case of immunoassay performance, a reducing environment must be maintained in solution for proper protein activity over the shelf life of the product. Diluents were designed with a number of metal chelators (EDTA, DTPA) and various levels of dithiothreitol (DTT) and glutathione to determine the impact of metal chelator on the stability of the reducing environment. A modified microtiter method was developed utilizing the Ellman's reagent (5,5′‐dithiobis‐(2‐nitrobenzoic acid) or DTNB) to provide a simple, robust and accurate quantitation of total sulfhydryl (SH) concentration. Using an accelerated stability model that incorporated various SH concentrations, temperatures, and storage times, the remaining SH concentrations were measured to determine a formulation that resulted in the most stable reducing environment. A formulation containing the chelator DTPA was shown to be the most successful and approximately doubled the stability of the diluents’ reducing environment in comparison to EDTA as measured per the model.
Ivabradine but not metoprolol preserves ex vivo function and glycolysis of working dyslipidemic mouse hearts without activation of stress signaling pathways
Authors: Vaillant Fanny , Lauzier Benjamin , Lachance Dominic , Rivard Marie‐Eve , Frayne Isabelle Robillard , Bolduc Virgine , Thorin Eric , Tardif Jean Claude , Rosiers Christine Des
Published: June 2021

Objective

Elevated heart rate (HR) increases the risk for severe complications in patients with coronary heart diseases. This study aimed at testing the functional and metabolic impact of chronic HR reduction (HRR) induced by the selective inhibitor of the pacemaker If current ivabradine (IVA) in comparison to the commonly used β‐blocker metoprolol (MET) in a dyslipidemic mouse model.

Methods

We assessed i) the functional and metabolic phenotype of dyslipidemic mouse hearts (ATX: hApoB+/+ LDLR−/−) perfused ex vivo in working mode, and ii) activity of nutrient signaling pathways in non‐perfused hearts, at 3 and 6 months either untreated or treated for 3 months with IVA or MET (10% HRR in vivo).

Results

Compared to their 3‐month‐old counterparts, 6‐month‐old ATX hearts displayed i) similar HR but decreased values (p<0.05) for cardiac output (25%) and power (22%), stroke volume (30%) and glycolysis (29%) when perfused ex vivo, and ii) exacerbated activation of energy and stress signaling pathways related to Akt, AMP kinase and the hexosamine biosynthetic pathway. All these alterations, except Akt, were attenuated by IVA (p<0.05) but tended to be exacerbated by MET.

Conclusion

In vivo chronic HRR induced by IVA but not MET limits alterations of ex vivo cardiac function and glycolysis, as well as of in vivo exacerbated activation of energy and stress signaling pathways associated with disease progression in ATX mouse.
Characterizing Unique Interaction Domains in Sterol Biosynthetic Complexes for the Control of Fungal Pathogens
Authors: Linscott Kristin , Chappell Joe , Niehaus Thomas
Published: June 2021

Invasive mycoses are a significant cause of patient morbidity and mortality, indicating a need for the development of new therapeutics through the characterization of novel biochemical targets. Squalene synthase catalyzes the first committed step in sterol biosynthesis. The overall architecture of this enzyme is similar across all kingdoms and consists of catalytic, linker, and membrane spanning domains. Recent findings in Sacchromyces cerevisiae revealed that the linker domain is necessary and sufficient for the auxotrophic complementation of sterol biosynthesis. Substitution of the mammalian or plant linker domain for the corresponding region in the yeast squalene synthase gene locus does not allow the yeast to meet its sterol requirement. Expression of the yeast linker domain, not the domain from animals or plants, is lethal in yeast. We aim to show that over‐expression of this linker domain is lethal in other fungal species and mediates interactions between proteins in a complex. We then plan to design small molecules that disrupt these interactions in a kingdom specific manner, providing evidence for the development of new, specific reagents to control the growth of fungal pathogens.
Testicular Macrophage Activity Correlates with Leydig Cell Apoptosis following Ethylene Dimethane Sulfonate (EDS) Treatment of Mature Male Sprague‐Dawley Rats
Authors: Singhal Barkha , Gebrehiwot Selam , Sang Samuel , Mills Nathaniel
Published: June 2021

Tumor necrosis factor alpha (Tnfα), a cytokine secreted by macrophages is known to initiate cell apoptosis. Other laboratories have reported that macrophages are directly associated with Leydig cells in testicular interstitium. Using reverse transcription of total RNA (RT) and real‐time quantifiable polymerase chain reaction (qPCR) with quantification of expression using the (−) ΔΔCt method, we found increased Tnfα mRNA expression within 24 hr of EDS treatment. We also found that CD68 mRNA (a macrophage/monocyte/dendritic cell marker) increased within 24 hr of EDS treatment. Thus, not only are macrophages present in testes but macrophages may also be increasing in cell number/testis following EDS treatment. Leydig cells are lost via apoptosis following EDS treatment and analysis of the Leydig cell markers, Lhr and Insl‐3 mRNA levels declined more than 80%. Since these genes are expressed primarily in Leydig cells, this suggested an 80% loss of Leydig cells by 24 hr. Using the TUNEL assay that detects DNA fragmentation, we confirmed that Leydig cell apoptosis is time dependent and is increased with increased time following EDS exposure. We suggest a potential paracrine action of macrophages through secretion of TNFα to induce Leydig cell apoptosis.
The Akt‐mTOR axis determines cell fate through the regulation of eIF2alpha phosphorylation pathway.
Authors: Koromilas Antonis E. , Tenkerian Clara , Mounir Zineb , Krishnamoorthy Jothi
Published: June 2021

Metazoans respond to environmental stress by inducing the phosphorylation of the α subunit of translation initiation factor eIF2 at S51 (eIF2αP), a modification that leads to protein synthesis inhibition. We demonstrate that eIF2αP is induced by pharmacological inhibition or genetic ablation of the PI3K‐Aktm‐TOR pathway (1). Increased eIF2αP is an evolutionary conserved process that involves the endoplasmic reticulum (ER)‐resident protein kinase PERK, which is negatively regulated by Akt dependent phosphorylation at T799. The PERK‐eIF2αP arm is downregulated by Akt in cells exposed to ER stress or oxidative stress leading to the induction of cell survival or death respectively. In unstressed cells, the PERK‐eIF2αP pathway guards survival and facilitates adaptation to the deleterious effects of PI3K, Akt or mTOR inactivation. Inactivation of the PERK‐eIF2αP arm sensitizes tumor death from pharmacological inhibition of the PI3K‐Akt‐mTOR pathway. The PERK‐eIF2αP pathway links Akt and mTOR signaling to translational control with implications in tumor treatment with pharmacological inhibitors of PI3K‐Akt‐mTOR pathway.
Diet quality tracking from preschool to school age in Brazilian children
Authors: Rauber Fernanda , Hoffman Daniel , Vitolo Marcia
Published: June 2021

Objective

To determine changes in diet quality in children from 3 to 8 years of age.

Methods

Two 24‐hour dietary recalls were collected when the children were 3 to 4 years (n=345) and 7 to 8 years of age (n=307). Diet quality was evaluated using the Healthy Eating Index (HEI). Analyses were performed by group, as all children had previously participated in a randomized trial, and using a paired t‐test.

Results

For all children, 80% had a diet that needed improvement (HEI = 51–80) at each time point and 14% of children at 3 to 4 years and none at 7 to 8 years had a good diet (HEI = >;80). Diet quality decreased over time for both intervention (67.7±10.4 vs. 59.3±8.1) and control (64.2±11.5 vs. 58.4±7.2) groups. In both groups, the score of fruits, milk and sodium decreased, while the score of saturated fat and variety increased. In the intervention group, the percent change was highest for sodium (−94.1%), fruits (−40.9%), and saturated fat (29.5%), while in the control group, the percent change was highest for sodium (−93.4%), vegetables (44.4%), and saturated fat (38.2%).

Conclusion

In the cohort studied, we found that the diet of children changed with a trend toward a lower diet quality. While the intake of some HEI components changed favorably, many dietary components were still below recommended levels.

Support: CNPq and CAPES, Brazil (F.R. doctoral fellowship, proc. no. 9853–11‐1).