Future prospects for partially ionized solar plasmas: the prominence case

Partially ionized plasmas (PIP) constitute an essential ingredient of our plasma universe. Historically, the physical effects associated with partial ionization were considered in astrophysical topics such as the interstellar medium, molecular clouds, accretion disks and, later on, in solar physics. PIP can be found in layers of the Sun's atmosphere as well as in solar structures embedded within it. As a consequence, the dynamical behaviour of these layers and structures is influenced by the different physical effects introduced by partial ionization. Here, rather than considering an exhaustive discussion of partially ionized effects in the different layers and structures of the solar atmosphere, we focus on solar prominences. The reason is that they represent a paradigmatic case of a partially ionized solar plasma, confined and insulated by the magnetic field, constituting an ideal environment to study the effects induced by partial ionization. We present the current knowledge about the effects of partial ionization in the global stability, mass cycle and dynamics of solar prominences. We revise the identified observational signatures of partial ionization in prominences. We conclude with prospects for PIP research in prominences, proposing the path for advancing in the prominence modelling and theory and using new and upcoming instrumentation. This article is part of the theme issue 'Partially ionized plasma of the solar atmosphere: recent advances and future pathways'.

Inhibition of corticosterone synthesis impairs cued water maze consolidation, but it does not affect the expression of BDNF, CK2 and SGK1 genes in dorsal striatum

Corticosterone (CORT) release during learning experiences is associated with strong memories and activity of the glucocorticoid receptor. It has been shown that lesions of the dorsal striatum (DS) of rats trained in the cued version of the Morris water maze impair memory, and that local injection of CORT improves its performance, suggesting that DS activity is involved in procedural memory which may be modulated by CORT. We trained rats in cued Morris water maze and analyzed the effect of CORT synthesis inhibition on performance, CORT levels, expression of plasticity-involved genes, such as the brain derived neurotrophic factor (BDNF), casein kinase 2 (CK2), and the serum/glucocorticoid regulated kinase 1 (SGK1), as well as the presence of phosphorylated nuclear glucocorticoid receptor in serine 232 (pGR-S232) in the DS. The inhibition of CORT synthesis by metyrapone reduced CORT levels in plasma, prevented its increment in DS and impaired the performance of cued water maze. Additionally, there was an increase of CK2 and SGK1 mRNAs expression in trained subjects, which was unrelated to CORT levels. Finally, we did not observe changes in nuclear pGR-S232 in any condition. Our findings agree with evidence demonstrating that decreasing CORT levels hinders acquisition and consolidation of the spatial version of the Morris water maze; these novel findings broaden our knowledge about the involvement of the DS in the mechanisms underlying procedural memory.

Mancha3D Code: Multipurpose Advanced Nonideal MHD Code for High-Resolution Simulations in Astrophysics

The Mancha3D code is a versatile tool for numerical simulations of magnetohydrodynamic (MHD) processes in solar/stellar atmospheres. The code includes nonideal physics derived from plasma partial ionization, a realistic equation of state and radiative transfer, which allows performing high-quality realistic simulations of magnetoconvection, as well as idealized simulations of particular processes, such as wave propagation, instabilities or energetic events. The paper summarizes the equations and methods used in the Mancha3D (Multifluid (-purpose -physics -dimensional) Advanced Non-ideal MHD Code for High resolution simulations in Astrophysics 3D) code. It also describes its numerical stability and parallel performance and efficiency. The code is based on a finite difference discretization and a memory-saving Runge-Kutta (RK) scheme. It handles nonideal effects through super-time-stepping and Hall diffusion schemes, and takes into account thermal conduction by solving an additional hyperbolic equation for the heat flux. The code is easily configurable to perform different kinds of simulations. Several examples of the code usage are given. It is demonstrated that splitting variables into equilibrium and perturbation parts is essential for simulations of wave propagation in a static background. A perfectly matched layer (PML) boundary condition built into the code greatly facilitates a nonreflective open boundary implementation. Spatial filtering is an important numerical remedy to eliminate grid-size perturbations enhancing the code stability. Parallel performance analysis reveals that the code is strongly memory bound, which is a natural consequence of the numerical techniques used, such as split variables and PML boundary conditions. Both strong and weak scalings show adequate performance up to several thousands of processors (CPUs).

KLF13 Regulates the Activity of the GH-Induced JAK/STAT Signaling by Targeting Genes Involved in the Pathway

The Krüppel-like factor 13 (KLF13) has emerged as an important transcription factor involved in essential processes of the central nervous system (CNS). It predominantly functions as a transcriptional repressor, impacting the activity of several signaling pathways with essential roles in the CNS, including the JAK/STAT pathway, which is the canonical mediator of growth hormone (GH) signaling. It is now recognized that GH has important actions as a neurotrophic factor. Therefore, we analyzed the effects of KLF13 on the activity of the JAK/STAT signaling pathway in the hippocampus-derived cell line HT22. Results showed that KLF13 directly regulates the expression of several genes involved in the JAK-STAT pathway, including Jak1, Jak2, Jak3, and Socs1, by associating with their proximal gene promoters. In addition, it was found that in KLF13-deficient HT22 neurons, the expression of Jak1, Stat3, Socs1, Socs3, and Igf1 was dysregulated, exhibiting mRNA levels that went up to 7-fold higher than the control cell line. KLF13 displayed a differential effect on the GH-induced JAK/STAT pathway activity, decreasing the STAT3 branch while enhancing the STAT5 branch. In KLF13-deficient HT22 cells, the activity of the STAT3 branch was enhanced, mediating the GH-dependent augmented expression of the JAK/STAT output genes Socs1, Socs3, Igf1, and Bdnf. Furthermore, GH treatment increased both the nuclear content of KLF13 and Klf13 mRNA levels, suggesting that KLF13 could be part of the mechanisms that maintain the homeostatic state of this pathway. These findings support the notion that KLF13 is a regulator of JAK/STAT activity.

Gonadotropin-releasing hormone and growth hormone act as anti-inflammatory factors improving sensory recovery in female rats with thoracic spinal cord injury

The potential for novel applications of classical hormones, such as gonadotropin-releasing hormone (GnRH) and growth hormone (GH), to counteract neural harm is based on their demonstrated neurotrophic effects in both in vitro and in vivo experimental models and a growing number of clinical trials. This study aimed to investigate the effects of chronic administration of GnRH and/or GH on the expression of several proinflammatory and glial activity markers in damaged neural tissues, as well as on sensory recovery, in animals submitted to thoracic spinal cord injury (SCI). Additionally, the effect of a combined GnRH + GH treatment was examined in comparison with single hormone administration. Spinal cord damage was induced by compression using catheter insufflation at thoracic vertebrae 10 (T10), resulting in significant motor and sensory deficits in the hindlimbs. Following SCI, treatments (GnRH, 60 μg/kg/12 h, IM; GH, 150 μg/kg/24 h, SC; the combination of both; or vehicle) were administered during either 3 or 5 weeks, beginning 24 h after injury onset and ending 24 h before sample collection. Our results indicate that a chronic treatment with GH and/or GnRH significantly reduced the expression of proinflammatory (IL6, IL1B, and iNOS) and glial activity (Iba1, CD86, CD206, vimentin, and GFAP) markers in the spinal cord tissue and improved sensory recovery in the lesioned animals. Furthermore, we found that the caudal section of the spinal cord was particularly responsive to GnRH or GH treatment, as well as to their combination. These findings provide evidence of an anti-inflammatory and glial-modulatory effect of GnRH and GH in an experimental model of SCI and suggest that these hormones can modulate the response of microglia, astrocytes, and infiltrated immune cells in the spinal cord tissue following injury.

Methylene Blue functionalized carbon nanodots combined with different shape gold nanostructures for sensitive and selective SARS-CoV-2 sensing

The development of DNA-sensing platforms based on new synthetized Methylene Blue functionalized carbon nanodots combined with different shape gold nanostructures (AuNs), as a new pathway to develop a selective and sensitive methodology for SARS-CoV-2 detection is presented. A mixture of gold nanoparticles and gold nanotriangles have been synthetized to modify disposable electrodes that act as an enhanced nanostructured electrochemical surface for DNA probe immobilization. On the other hand, modified carbon nanodots prepared a la carte to contain Methylene Blue (MB-CDs) are used as electrochemical indicators of the hybridization event. These MB-CDs, due to their structure, are able to interact differently with double and single-stranded DNA molecules. Based on this strategy, target sequences of the SARS-CoV-2 virus have been detected in a straightforward way and rapidly with a detection limit of 2.00 aM. Moreover, this platform allows the detection of the SARS-CoV-2 sequence in the presence of other viruses, and also a single nucleotide polymorphism (SNPs). The developed approach has been tested directly on RNA obtained from nasopharyngeal samples from COVID-19 patients, avoiding any amplification process. The results agree well with those obtained by RT-qPCR or reverse transcription quantitative polymerase chain reaction technique.

Prolactin Expression in the Baboon (Papio hamadryas) Eye

Prolactin (PRL) is a hormone expressed in lactotrophs cells of the pituitary gland in primates. Extra pituitary expression of PRL has been reported, including the eye; however, expression in the developing eye of primates is limited. The aim of the study was determining the expression of PRL and PRL receptor (PRLR) (mRNAs and proteins) in adult and fetal baboon (Papio hamadryas) ocular tissues.

METHODS

We analyzed PRL and PRLR in baboon eyes tissues by immunofluorescence. The mRNAs of PRL and PRLR were detected by RT-PCR, cDNA was cloned, and sequenced. Furthermore, we performed a phylogenetic analysis to identify the evolutionary forces that underlie the divergence of PRL and PRLR primate genes.

RESULTS

We observed the expression of PRL and PRLR (mRNAs and proteins) in all retinal cell lineages of fetal and adult baboon. PRL and PRLR fit the hypothesis of evolutionary purifying gene selection.

CONCLUSIONS

mRNA and protein of PRL and PRLR are expressed in fetal and adult baboon retinal tissue. PRL may trigger autocrine and paracrine-specific actions in retinal cell lines.

P-366 Tumor necrosis factor-alpha and milk fat globule-epidermal growth factor 8: novel biomarkers to predict implantation failure and pregnancy loss

Study question

Can implantation failure (IF) and pregnancy loss be predicted in serum prior to in vitro fertilization (IVF)?

Summary answer

Tumor necrosis factor (TNFα) and milk fat globule-epidermal growth factor 8 (MFG-E8) levels may serve as serum markers to predict IF and pregnancy loss.

What is known already

In a normal pregnancy, mediators such as TNFα are released creating a physiological inflammatory response. However, an exaggerated release of TNFα has been associated with IF and recurrent pregnancy loss (RPL). Recent studies demonstrated that TNFα up-regulates the expression of inflammatory factors such as MFG-E8. MFG-E8 is known to modulate implantation by acting at various levels of the trophoblast and endometrial compartments. Hence an overexpression of this protein may result in apoptosis, endometrial damage, and impaired implantation.

Study design, size, duration

This multicentric prospective controlled pilot clinical study was conducted from January 2016 to January 2020 and included 30 women in their natural cycle in which serum MFG-E8, TNFα, estradiol (E2), and progesterone (P4) levels were quantified in the early proliferative (cycle day 2) and secretory phases (urinary LH + 7 days). Additionally, an endometrial biopsy was obtained on urinary LH + 7 days for MFG-E8 and TNF α protein and gene expression analysis.

Participants/materials, setting, methods

Women ages 21-35y were recruited from 3 groups: fertile controls (C), unexplained IF (following 3 failed good quality embryo transfers), and RPL (at least 2 unexplained first trimester miscarriages). Patients with history of uterine surgery, abnormal uterine cavity (fibroids, endometrial polyps, adhesions, adenomyosis, and congenital uterine abnormalities), hydrosalpinx, diminished ovarian reserve, harboring chromosomal rearrangements, thrombophilia, or autoimmune diseases were excluded.

Main results and the role of chance

Ten women were included in each group. No statistical differences were found in age, BMI, AMH, baseline FSH, and baseline antral follicle count among cohorts. Mean serum E2 and P4 levels were similar among all groups in both the proliferative and secretory phases: E2 proliferative (C 69.19±26.64  pg/ml, IF 64.19±32.56  pg/ml, RPL proliferative 57.44±38.51; p = 0.55), E2 secretory (C 164.10±52.57  pg/ml, IF 172.57±121, RPL 173.81±.97.35; p = 0.25), P4 proliferative (C 0.45±0.15 ng/ml, IF 0.45±0.19 ng/ml, RPL 0.53±0.18 ng/ml; p = 0.85), P4 secretory (C 7.42±4.06 ng/ml, IF 7.8±4.56 ng/ml, RPL 8.05±4.38 ng/ml; p = 0.74). Mean serum TNFα levels were significantly higher in both, the proliferative and secretory phases for the RPL group (proliferative RPL 9.98±4.47  pg/ml, IF 4.73±2.56  pg/ml, C 3.42±1.01  pg/ml; p = 0.001 vs secretory RPL 8.67±4.45  pg/ml, C 3.35±0.94  pg/ml, IF 3.85±1.01  pg/ml; p = 0.03). Mean serum MFG-E8 levels were significantly higher in the IF group during the proliferative phase (IF 373±201  pg/ml, RPL 201±115  pg/ml, C 225.58±109.73pg/ml; p = 0.03), but not in the secretory phase (IF 237±101  pg/ml, RPL 189±116  pg/ml, C 199.41±112.43  pg/ml; p = 0.15). Endometrial MFG-E8 mRNA levels were significantly lower in the IF and RPL group compared to C (p = 0.03). TNFα mRNA levels were not statistically significant among groups (p = 0.12).

Limitations, reasons for caution

This is a pilot study to assess feasibility. Due to the small sample size, the effects of more subtle covariates would not have been detected. Future larger studies are warranted.

Wider implications of the findings

These novels differentially expressed serum and endometrial markers may provide information on the physiology of implantation and could generate the basis for non-invasive diagnostic tools and therapeutic use of MFG-E8/TNFα antagonists in women with IF and RPL.

Trial registration number

IIT-2014-100366

P-704 Post trigger progesterone levels as a predictor of oocyte recovery rate

Study question

Do progesterone (P) levels the day after trigger for oocyte maturation impact the oocyte recovery rate?

Summary answer

A progesterone cutoff value of ≤ 5.0 ng/ml the day after trigger for oocyte maturation is associated with a lower oocyte recovery rate.

What is known already

Oocyte maturation and embryo development are controlled by intra-ovarian factors such as steroid hormones. P exists in the follicular fluid, and it is known to mediate some luteinizing hormone (LH)- initiated periovulatory events through autocrine/paracrine mechanisms that help mediate granulasa cell luteinization and oocyte maturation. More importantly, a rise in P levels is associated with an adequate follicular rupture. To date, no study has evaluated if lower P levels after oocyte maturation induction are a reflection of impaired physiological periovulatory mechanisms required for the oocyte release from the follicular wall.

Study design, size, duration

This monocentric retrospective analysis from January 2017 to December 2021 included 435 controlled ovarian hyperstimulation cycles for in vitro fertilization (IVF)/ egg freezing. Serum P, estradiol (E2), bHCG, and LH levels were measured the day after trigger for oocyte maturation to assure adequate luteinization.

Participants/materials, setting, methods

Women <4O years, that underwent controlled ovarian hyperstimulation with a GnRH antagonist protocol and final oocyte maturation (when ≥2 follicles reached ≥18 mm in diameter) induction with dual trigger (Leuprolide acetate and hCG) were segregated into two groups: Group 1: progesterone cutoff value of ≤ 5.0 ng/ml the day after trigger; Group 2: progesterone cutoff value of ≥ 5.1 ng/ml the day after trigger.

Main results and the role of chance

147 cycles in Group 1 were compared with 288 cycles on Group 2. No significant differences were noted in mean patient’s age, BMI, baseline FSH, AMH, baseline antral follicle count, serum P and E2 levels the day of trigger, total dose of gonadotropins, day of trigger as well as serum E2, LH, and bHCG levels the day after trigger among cohorts. A total of 5765 oocytes were retrieved: 1703 corresponding to group 1 and 4692 to group B. Women with progesterone levels higher than ≥5.1 ng/ml the day after trigger had a greater number of oocytes retrieved compared to women with a progesterone cutoff value of ≤ 5.0 ng/ml (16.3 ± 9.1 versus 11.5 ± 7.4, p = < 0.0001). The oocyte/follicle rate was also significantly higher in women in Group 2 vs Group 1 (80.3% vs 63.7%, p = 0.003)  However, the mature oocyte (MII) rate was comparable among cohorts (Group 1: 78.0 ± 20.2% vs Group 2: 78.8 ± 17.7%, p = 0.38).

Limitations, reasons for caution

The retrospective nature of the study, small sample size, selected progesterone cutoff value, and progesterone assay techniques compared to other ART centers may limit the external validity of our findings.

Wider implications of the findings

Our findings suggest for the first time that lower progesterone levels after final oocyte maturation induction may be a result of compromised mechanisms associated with the release of the oocyte from the follicular wall as demonstrated by a lower oocyte recovery rate.

Trial registration number

NA

Analysis of telephone demand in a heart failure unit: something more than a simple call

Introduction

Specific care programs for HF patients significantly reduce readmissions, which is why they are recommended in clinical practice guidelines with the highest level of evidence. Telephone assistance is a service offered to patients within these programs.

Purpose

The main objective was to evaluate the most frequent reasons for consultation and the ability to resolve them after the call.

Methods

This is a descriptive, retrospective study of all the telephone consultations registered between June 2020 and January 2021. The calls are attended by the HF consultation nurse, commenting with Cardiology on those that imply changes in the pharmacological treatment.

Sociodemographic and clinical variables, reasons for the call and their frequency were collected. Categorical variables were expressed as percentages and quantitative variables as means ± standard deviation.

Results

During the analyzed period, 1.608 consultations were attended, 494 were telephone calls, which represents 31% of the overall activity of the nursing consultation. 423 consultations were analyzed, 55.7% (235) reactive, and 44.3% (187) proactive. 72.5% of the patients were under follow-up by the nurse, compared to 27.5% who had completed drug titration.

The mean age was 65 (± 12.3) years, 65.6% were men, 98.4% had a caregiver, 77% of the patients had an LVEF <40%, Charlson modified mean 4.7 (± 3.6) and 92.3% were on treatment with beta-blockers, 89.1% with ACE inhibitors/ARBs/ARNI and 82.3% with MRA. The mean number of drugs per patient was 8.6 (± 3).

Reasons for the reactive calls were in 46% of the cases the consultation of symptoms, 20% to consult doubts about the treatment or procedures, 16% for problems related to the prescription of pharmacological treatment and 14% for the appointment management.

Reasons for proactive calls were 40% for symptoms control, 30.5% for appointment management, 27.3% for drug titration and 2.1% related to other causes.

When the reason for consultation was the appearance of symptoms, the mean number of calls required was 1.4 (± 0.8), 77.6% of the calls were solved through the telephone, 16.4% required a face-to-face visit in the nursing consultation and 2.7% were referred to the emergency room. Queries related to doubts, problems with the prescription or appointment management were solved in a single telephone consultation.

Conclusions

The most common telephone request when the patient made the call was the worsening of HF symptoms. The telephone consultation is presented as an effective tool in these cases, by favoring the accessibility of patients and avoiding unnecessary trips to the health center.

Funding Acknowledgement

Type of funding sources: None. Table 1. Descriptive details of patientsTable 2. Call reasons

Analysis of LpA levels in young patients after ACS: getting to know less famous risk factors

Introduction

Lipoprotein A (LpA) has been shown to be an emerging risk factor, proposing that values greater than 60 mg/dl increases cardiovascular risk. There are few data about LpA values in young patients who have suffered a major cardiovascular event.

Purpose

The objective of this work was to describe the LpA values observed in young patients admitted for acute coronary syndrome in our center, and subsequently to compare these values according to the patients' previous cardiovascular risk.

Methods

This is a descriptive and observational study, in which all male patients under 65 years and women under 70 years who have suffered STEMI or NSTEMI from November 2019 to February 2021 admitted to our center were consecutively included. In addition to LpA values, the following variables were recollected: age, sex, high blood pressure, diabetes mellitus, dyslipidemia, stroke, chronic kidney injury, smoking, alcoholism, toxics, total cholesterol and SCORE risk.

Results

159 patients were included. The mean of LpA value was 41,08 mg/dl (standard deviation 38, range 1–155, percentile 25th: 9,7; percentile 50th: 28,8; percentile 75th: 59,1). 24,5% presented levels of LpA greater than 60 mg/dl. The percentage of patients with LpA levels >60 mg was 32,4% in low SCORE group and 22,4% in greater than low SCORE group without significant differences.

The table compares the LpA values according to the cardiovascular risk SCORE those patients presented before the acute coronary syndrome (low SCORE vs moderate, high or very high SCORE). As we can see in the table, we found a trend to present higher LpA values in patients with low SCORE risk compared to those with higher than low SCORE risk, without reaching statistical significance.

Conclusions

In a sample of young patients with acute coronary syndrome, the LpA mean was 41,08 mg/dl. 24,5% of patients had values of LpA greater than 60 mg/dl. No significant differences were found according to the SCORE prior to the event, although there was a non-significant trend towards a higher LpA in patients with low SCORE.

Funding Acknowledgement

Type of funding sources: None. Table 1. LpA values

P–685 Luteinization after final oocyte maturation induction is not compromised in women that receive double dose of Gonadotrophin-releasing hormone antagonists during controlled ovarian hyperstimulation

Study question

Does the use of double dose of GnRH antagonists during COH in women with risk of premature LH surge alter luteinization after final oocyte maturation induction?

Summary answer

The use of double dose of GnRH antagonist in women with risk of premature luteinizing hormone surge dosent affect luteinization after final oocyte maturation induction.

What is known already

GnRH antagonists are used to prevent a premature LH surge during controlled ovarian hyperstimulation. The antagonists directly inhibit gonadotrophin release within several hours through competitive binding to pituitary GnRH receptors, producing a rapid suppression of LH and FSH, with no initial flare effect. In women with diminished ovarian reserve (DOR) it is not uncommon that premature luteinization cannot be completely prevented using a daily dose GnRH antagonist. To date, no study has evaluated the effects of using a daily double dose of GnRH antagonists to prevent a premature LH surge and its effect on luteinization after final oocyte maturation induction.

Study design, size, duration

This monocentric retrospective analysis evaluated the effect on luteinization after final oocyte maturation induction in twenty women during COH who received a daily double dose of GnRH antagonists (Cetrotide 0.25 mg/mL, Merck) from January 2020 to December 2020.

Participants/materials, setting, methods

Women with severe DOR and history of premature luteinization during COH received a double dose of GnRH antagonist when the leading follicle reached 12–14 mm (am and pm). When two follicles reached ≥18 mm in diameter, final oocyte maturation was induced with dual trigger using Leuprolide acetate and hCG. Progesterone, estradiol, bHCG, and LH levels were measured the day after final oocyte maturation induction to assure adequate luteinization.

Main results and the role of chance

In total twenty women were included in the analysis. Mean age 36.8± 4.2, AMH 0.65± 0.32 ng/ml, baseline antral follicle count 4± 2.3, serum hormone levels the day of ovulation induction trigger: progesterone 0.89± 0.34 ng/ml, LH 1.6± 2.1 ng/ml, estradiol 1235 ± 1420 pg/ml. Post-surge serum hormone levels average reached adequate levels: estradiol 1645 ± 1116 pg/ml, progesterone 20.4 ±2.2 ng/ml, LH 62.66± 10.5 IU/ml and, bHCG 247±115 IU/ml. A total of 76 oocytes were retrieved (3.8± 0.8 oocytes per patient), 63.1% (48/76) MII, 22% (17/76) MI, 14% (11/76) GV.

Limitations, reasons for caution

The retrospective nature of the study, small sample size, and potential variability in the study center’s laboratory protocol(s) compared to other reproductive treatment centers may limit the external validity of our findings.

Wider implications of the findings: The daily use of double dose of GnRH antagonists during COH offers the possibility of preventing a premature LH surge in women with DOR with high risk of early ovulation, without compromising luteinization after final oocyte maturation induction.

Trial registration number

NA

Neuroprotective Effects of Growth Hormone (GH) and Insulin-Like Growth Factor Type 1 (IGF-1) after Hypoxic-Ischemic Injury in Chicken Cerebellar Cell Cultures

It has been reported that growth hormone (GH) and insulin-like growth factor 1 (IGF-1) exert protective and regenerative actions in response to neural damage. It is also known that these peptides are expressed locally in nervous tissues. When the central nervous system (CNS) is exposed to hypoxia-ischemia (HI), both GH and IGF-1 are upregulated in several brain areas. In this study, we explored the neuroprotective effects of GH and IGF-1 administration as well as the involvement of these endogenously expressed hormones in embryonic chicken cerebellar cell cultures exposed to an acute HI injury. To induce neural damage, primary cultures were first incubated under hypoxic-ischemic (<5% O₂, 1g/L glucose) conditions for 12 h (HI), and then incubated under normal oxygenation and glucose conditions (HI + Ox) for another 24 h. GH and IGF-1 were added either during or after HI, and their effect upon cell viability, apoptosis, or necrosis was evaluated. In comparison with normal controls (Nx, 100%), a significant decrease of cell viability (54.1 ± 2.1%) and substantial increases in caspase-3 activity (178.6 ± 8.7%) and LDH release (538.7 ± 87.8%) were observed in the HI + Ox group. On the other hand, both GH and IGF-1 treatments after injury (HI + Ox) significantly increased cell viability (77.2 ± 4.3% and 72.3 ± 3.9%, respectively) and decreased both caspase-3 activity (118.2 ± 3.8% and 127.5 ± 6.6%, respectively) and LDH release (180.3 ± 21.8% and 261.6 ± 33.9%, respectively). Incubation under HI + Ox conditions provoked an important increase in the local expression of GH (3.2-fold) and IGF-1 (2.5-fold) mRNAs. However, GH gene silencing with a specific small-interfering RNAs (siRNAs) decreased both GH and IGF-1 mRNA expression (1.7-fold and 0.9-fold, respectively) in the HI + Ox group, indicating that GH regulates IGF-1 expression under these incubation conditions. In addition, GH knockdown significantly reduced cell viability (35.9 ± 2.1%) and substantially increased necrosis, as determined by LDH release (1011 ± 276.6%). In contrast, treatments with GH and IGF-1 stimulated a partial recovery of cell viability (45.2 ± 3.7% and 53.7 ± 3.2%) and significantly diminished the release of LDH (320.1 ± 25.4% and 421.7 ± 62.2%), respectively. Our results show that GH, either exogenously administered and/or locally expressed, can act as a neuroprotective factor in response to hypoxic-ischemic injury, and that this effect may be mediated, at least partially, through IGF-1 expression.

Waddling beyond door to balloon times and impinging true ischemic times with artificial intelligence-guided single lead EKG for STEMI detection

Background

The present process of STEMI detection is cumbersome as it utilizes outdated equipment and requires a trained technician and an expert cardiologist. We have developed a patient-administered, Artificial Intelligence (AI) guided, Single Lead EKG for early STEMI detection.

Purpose

To answer the question “Is early STEMI detection possible with a Single Lead EKG?”

Methods

We experimented with an AI-guided algorithm for a single-lead EKG for STEMI detection with the following step-wise developments: 1) An AI algorithm that predictably interprets STEMI using a 12-lead EKG; 2) An AI algorithm for STEMI detection using a single-lead EKG; 3) A methodology for identifying the best single lead to detect STEMI; 4) Advanced AI algorithms for STEMI localization with a single-lead EKG. The AI methodology was as follows: Sample: The mammoth Latin American Telemedicine Infarct Network telemedicine database that provides an umbrella of AMI management to 100 million patients in Brazil, Colombia, Mexico, Chile, and Argentina was queried for cardiologist annotated EKG. A total of 8,511 EKG and 90,592 classified heartbeats were selected for the experiments. Preprocessing: segmentation of each ECG into individual heartbeats. Training & Testing: 90% and 10%, respectively, of the total dataset. Classification: 1-D Convolutional Neural Network; classes were construed for each heartbeat. Performance indicators were calculated per lead.

Results

The algorithm was able to provide an accuracy of 91.9%. Lead V2 yielded the best results among individual leads for STEMI detection.

Conclusions

Early experiments provide a framework for augmenting STEMI detection with the use of AI-guided, single lead techniques. Such approaches seem rational as we target the reduction of true STEMI ischemic times.

Funding Acknowledgement

Type of funding source: None

Moving in sync – concordance betweena artificial intelligence and cardiologist on detecting normal electrocardiograms

Background

Merging modern technologies with classic diagnostic tests often results in a sense of insecurity within the medical community, particularly so with potentially life-saving studies such as the electrocardiogram (EKG). In order to provide a greater sense of trust between Artificial Intelligence (AI) and cardiologists, we provide an AI-driven algorithm capable of accurately and reliably characterize an EKG as normal within a highly complex, cardiologist-reviewed EKG database and report the degree of concordance between this machine vs physician scenario.

Purpose

To provide a dependable and accurate AI algorithm that conducts EKG interpretation in a cardiologist-tier manner.

Methods

The International Telemedical System (ITMS) developed and tested an EKG assessing AI algorithm and incorporated it into the workflow of their Telemedicine Integrated Platform, a digital EKG reading program where cardiologists continuously report their findings remotely in real-time. During the month of April 2,019; 35 ITMS cardiologists reported a grand total of 61,441 EKG records, later submitting them to the AI algorithm implemented through the “One Click Report” process. Through this simple 2-step approach, the algorithm provides a suggestion of “Normal” or “Abnormal” to the cardiologist based on the patterns of the fiducial points included in said EKG reports. Confirmation of these suggestions by the cardiologists ensued.

Results

Overall, cardiologists confirmed 23,213 out of 25,013 AI outputs for “Normal” EKGs, demonstrating a concordance of 92.8% for Normal diagnosis.

Conclusion

Through this methodology, we provide an AI technology that can be reliably applied and trusted in EKG digital platforms to identify and suitably label a normal EKG. Further testing will accrue into a multi label algorithm compatible with abnormal cardiovascular entities, potentially precluding the role of the cardiologist for triaging, particularly in the prehospital setting. We anticipate that this approach will become a promising methodology in modern cardiology practice.

Funding Acknowledgement

Type of funding source: None

Baby steps in the path of modifying the role of cardiologists for interpreting EKG for AMI

Background

EKG interpretation is slowly transitioning to a physician-free, Artificial Intelligence (AI)-driven endeavor. Our continued efforts to innovate follow a carefully laid stepwise approach, as follows: 1) Create an AI algorithm that accurately identifies STEMI against non-STEMI using a 12-lead EKG; 2) Challenging said algorithm by including different EKG diagnosis to the previous experiment, and now 3) To further validate the accuracy and reliability of our algorithm while also improving performance in a prehospital and hospital settings.

Purpose

To provide an accurate, reliable, and cost-effective tool for STEMI detection with the potential to redirect human resources into other clinically relevant tasks and save the need for human resources.

Methods

Database: EKG records obtained from Latin America Telemedicine Infarct Network (Mexico, Colombia, Argentina, and Brazil) from April 2014 to December 2019. Dataset: A total of 11,567 12-lead EKG records of 10-seconds length with sampling frequency of 500 [Hz], including the following balanced classes: unconfirmed and angiographically confirmed STEMI, branch blocks, non-specific ST-T abnormalities, normal and abnormal (200+ CPT codes, excluding the ones included in other classes). The label of each record was manually checked by cardiologists to ensure precision (Ground truth). Pre-processing: The first and last 250 samples were discarded as they may contain a standardization pulse. An order 5 digital low pass filter with a 35 Hz cut-off was applied. For each record, the mean was subtracted to each individual lead. Classification: The determined classes were STEMI (STEMI in different locations of the myocardium – anterior, inferior and lateral); Not-STEMI (A combination of randomly sampled normal, branch blocks, non-specific ST-T abnormalities and abnormal records – 25% of each subclass). Training & Testing: A 1-D Convolutional Neural Network was trained and tested with a dataset proportion of 90/10; respectively. The last dense layer outputs a probability for each record of being STEMI or Not-STEMI. Additional testing was performed with a subset of the original dataset of angiographically confirmed STEMI.

Results

See Figure Attached – Preliminary STEMI Dataset Accuracy: 96.4%; Sensitivity: 95.3%; Specificity: 97.4% – Confirmed STEMI Dataset: Accuracy: 97.6%; Sensitivity: 98.1%; Specificity: 97.2%.

Conclusions

Our results remain consistent with our previous experience. By further increasing the amount and complexity of the data, the performance of the model improves. Future implementations of this technology in clinical settings look promising, not only in performing swift screening and diagnostic steps but also partaking in complex STEMI management triage.

Funding Acknowledgement

Type of funding source: None

Artificial intelligence methodology: multi-label classification of abnormal EKG records

Background

Our previous experience with Artificial Intelligence (AI)-conducted EKG characterization displayed outstanding results in fast and reliable identification of Normal EKGs within the International Telemedical System (ITMS)'s massive record repository. By expanding the array of recognizable cardiovascular entities, we upgraded our methodology to accurately discriminate an anomaly amongst a highly complex database of EKG records.

Purpose

To present a feasible AI-guided filter that can accurately discriminate and classify Normal and Abnormal EKG records within a multilabeled cardiologist-annotated EKG database.

Methods

ITMS developed and tested the “One Click”' process, a “Normal/Abnormal” EKG assessing AI algorithm, by incorporating it into their digital EKG reading platform where cardiologists continuously report their findings remotely in real time. To ameliorate the diagnostic range of the algorithm, a separate dataset of 121,641 12-lead EKG records was consolidated from the ITMS database from October 2011 to January 2019. Only de-identified data was used. Preprocessing: The first 2s of each short lead and 9s of the long lead were considered. Limb leads I, II and III; and precordial leads V1, V2, V3, and V5 were used. The mean was removed from each lead. AI models/Classification: Two models were created and tested independently based on the method of EKG acquisition (69,852 records transtelephonic [TTP]; 52,259 mobile transmission [MOB]). Each record is categorized into six disjoint classes based on the most common types of cardiac disorders (Low/null co-occurrence pathologies in these datasets were grouped into analogous groups). Training/Testing: Distribution of both sets per transmission type was performed through a greedy algorithm, which identified multiple diagnoses per EKG record and labeled it separately to the corresponding group, ensuring sufficient samples per class. Detailed class distribution is shown below. An inception convolutional neural network was implemented; “Normal” or “Abnormal” labels were assigned to each EKG record independently and were compared to cardiologists' reports; performance indicators were calculated for each model and group.

Results

MOB model accrued an average accuracy of 86.7%; sensitivity of 90.5%; and specificity of 83.9%. TTP model yielded an average accuracy of 77.2%; sensitivity of 91.1%; and specificity of 69.4% (Lower values were attributed to the “Ventricular Complexes” group, which challenged the algorithm by having a smaller ratio of abnormal exams). Detailed results of each training set are shown below.

Conclusion

Providing an effective and reliable multilabel-capable EKG triaging tool remains a challenging but attainable goal. Continuous systematic enhancement of our AI-driven methodology has led us to satisfactory, yet imperfect results which compel us to further study and improve our efforts to provide a trustworthy cardiologist-friendly triage device.

Funding Acknowledgement

Type of funding source: None

Differential Phosphorylation of the Glucocorticoid Receptor in Hippocampal Subregions Induced by Contextual Fear Conditioning Training

Aversive events induce the release of glucocorticoid stress hormones that facilitate long-term memory consolidation, an effect that depends on the activation of glucocorticoid receptors (GRs). GRs are distributed widely in the hippocampus. The dorsal region of the hippocampus has been related to cognitive functions and the ventral region to stress and emotion. GR acts as a transcription factor which after hormone binding becomes phosphorylated, affecting its cellular distribution and transcriptional activity. Two functionally well-described GR phosphorylation sites are serine 232 (pSer232), which enhances gene expression, and serine 246 (pSer246), having the opposite effect. Since gene expression is one of the plastic mechanisms needed for memory consolidation, we investigated if an aversive learning task would induce GR phosphorylation in the dorsal (DH) and the ventral (VH) hippocampus. We trained rats in contextual fear conditioning (CFC) using different foot-shock intensities (0.0, 0.5, or 1.5 mA). One subgroup of animals trained with each intensity was sacrificed 15 min after training and blood was collected to quantify corticosterone (CORT) levels in serum. Another subgroup was sacrificed 1 h after training and brains were collected to evaluate the immunoreactivity (IR) to GR, pSer232 and pSer246 by SDS-PAGE/Western blot in DH and VH, and by immunohistochemistry in dorsal and ventral CA1, CA2, CA3, and dentate gyrus (DG) hippocampal regions. The conditioned freezing response increased in animals trained with 0.5 and 1.5 mA during training and extinction sessions. The degree of retention and CORT levels were directly related to the intensity of the foot-shock. Although total GR-IR remained unaffected after conditioning, we observed a significant increase of pSer246-IR in the dorsal region of CA1 and in both dorsal and ventral DG. The only region in which pSer232-IR was significantly elevated was ventral CA3. Our results indicate that fear conditioning training is related to GR phosphorylation in specific subregions of the hippocampus, suggesting that its transcriptional activity for gene expression is favored in ventral CA3, whereas its repressor activity for gene-silencing is increased in dorsal CA1 and in both dorsal and ventral DG.

Thyrotropin-Releasing Hormone (TRH) and Somatostatin (SST), but not Growth Hormone-Releasing Hormone (GHRH) nor Ghrelin (GHRL), Regulate Expression and Release of Immune Growth Hormone (GH) from Chicken Bursal B-Lymphocyte Cultures

It is known that growth hormone (GH) is expressed in immune cells, where it exerts immunomodulatory effects. However, the mechanisms of expression and release of GH in the immune system remain unclear. We analyzed the effect of growth hormone-releasing hormone (GHRH), thyrotropin-releasing hormone (TRH), ghrelin (GHRL), and somatostatin (SST) upon GH mRNA expression, intracellular and released GH, Ser133-phosphorylation of CREB (pCREB^S133), intracellular Ca²⁺ levels, as well as B-cell activating factor (BAFF) mRNA expression in bursal B-lymphocytes (BBLs) cell cultures since several GH secretagogues, as well as their corresponding receptors (-R), are expressed in B-lymphocytes of several species. The expression of TRH/TRH-R, ghrelin/GHS-R1a, and SST/SST-Rs (Subtypes 1 to 5) was observed in BBLs by RT-PCR and immunocytochemistry (ICC), whereas GHRH/GHRH-R were absent in these cells. We found that TRH treatment significantly increased local GH mRNA expression and CREB phosphorylation. Conversely, SST decreased GH mRNA expression. Additionally, when added together, SST prevented TRH-induced GH mRNA expression, but no changes were observed in pCREB^S133 levels. Furthermore, TRH stimulated GH release to the culture media, while SST increased the intracellular content of this hormone. Interestingly, SST inhibited TRH-induced GH release in a dose-dependent manner. The coaddition of TRH and SST decreased the intracellular content of GH. After 10 min. of incubation with either TRH or SST, the intracellular calcium levels significantly decreased, but they were increased at 60 min. However, the combined treatment with both peptides maintained the Ca²⁺ levels reduced up to 60-min. of incubation. On the other hand, BAFF cytokine mRNA expression was significantly increased by TRH administration. Altogether, our results suggest that TRH and SST are implicated in the regulation of GH expression and release in BBL cultures, which also involve changes in pCREB^S133 and intracellular Ca²⁺ concentration. It is likely that TRH, SST, and GH exert autocrine/paracrine immunomodulatory actions and participate in the maturation of chicken BBLs.

Growth Hormone Neuroprotection Against Kainate Excitotoxicity in the Retina is Mediated by Notch/PTEN/Akt Signaling

Purpose

In the retina, growth hormone (GH) promotes axonal growth, synaptic restoration, and protective actions against excitotoxicity. Notch signaling pathway is critical for neural development and participates in the retinal neuroregenerative process. We investigated the interaction of GH with Notch signaling pathway during its neuroprotective effect against excitotoxic damage in the chicken retina.

Methods

Kainate (KA) was used as excitotoxic agent and changes in the mRNA expression of several signaling markers were determined by qPCR. Also, changes in phosphorylation and immunoreactivity were determined by Western blotting. Histology and immunohistochemistry were performed for morphometric analysis. Overexpression of GH was performed in the quail neuroretinal-derived immortalized cell line (QNR/D) cell line. Exogenous GH was administered to retinal primary cell cultures to study the activation of signaling pathways.

Results

KA disrupted the retinal cytoarchitecture and induced significant cell loss in several retinal layers, but the coaddition of GH effectively prevented these adverse effects. We showed that GH upregulates the Notch signaling pathway during neuroprotection leading to phosphorylation of the PI3K/Akt signaling pathways through downregulation of PTEN. In contrast, cotreatment of GH with the Notch signaling inhibitor, DAPT, prevented its neuroprotective effect against KA. We identified binding sites in Notch1 and Notch2 genes for STAT5. Also, GH prevented Müller cell transdifferentiation and downregulated Sox2, FGF2, and PCNA after cotreatment with KA. Additionally, GH modified TNF receptors immunoreactivity suggesting anti-inflammatory actions.

Conclusions

Our data indicate that the neuroprotective effects of GH against KA injury in the retina are mediated through the regulation of Notch signaling. Additionally, anti-inflammatory and antiproliferative effects were observed.

Regenerative Effect of Growth Hormone (GH) in the Retina after Kainic Acid Excitotoxic Damage

In addition to its role as an endocrine messenger, growth hormone (GH) also acts as a neurotrophic factor in the central nervous system (CNS), whose effects are involved in neuroprotection, axonal growth, and synaptogenic modulation. An increasing amount of clinical evidence shows a beneficial effect of GH treatment in patients with brain trauma, stroke, spinal cord injury, impaired cognitive function, and neurodegenerative processes. In response to injury, Müller cells transdifferentiate into neural progenitors and proliferate, which constitutes an early regenerative process in the chicken retina. In this work, we studied the long-term protective effect of GH after causing severe excitotoxic damage in the retina. Thus, an acute neural injury was induced via the intravitreal injection of kainic acid (KA, 20 µg), which was followed by chronic administration of GH (10 injections [300 ng] over 21 days). Damage provoked a severe disruption of several retinal layers. However, in KA-damaged retinas treated with GH, we observed a significant restoration of the inner plexiform layer (IPL, 2.4-fold) and inner nuclear layer (INL, 1.5-fold) thickness and a general improvement of the retinal structure. In addition, we also observed an increase in the expression of several genes involved in important regenerative pathways, including: synaptogenic markers (DLG1, NRXN1, GAP43); glutamate receptor subunits (NR1 and GRIK4); pro-survival factors (BDNF, Bcl-2 and TNF-R2); and Notch signaling proteins (Notch1 and Hes5). Interestingly, Müller cell transdifferentiation markers (Sox2 and FGF2) were upregulated by this long-term chronic GH treatment. These results are consistent with a significant increase in the number of BrdU-positive cells observed in the KA-damaged retina, which was induced by GH administration. Our data suggest that GH is able to facilitate the early proliferative response of the injured retina and enhance the regeneration of neurite interconnections.

Physiological changes of growth hormone during lactation in pup rats artificially reared

During the lactation period, rat pups are fed by the dam, and the patterns of mother-pup interaction change during this period. Additionally, there are changes in feeding; first, mother´s milk is the only food needed for sustenance, and later, it is combined with solid food and water. GH serum concentrations depend on both maternal-pup interaction and energy metabolism. In the artificial rearing (AR) procedure, pups are deprived of mother-pup interaction, and the feeding pattern is controlled. This rearing paradigm has been used in rats to analyze the effects of maternal deprivation on social behavior. In the present study, we analyzed the variation in GH, acylated ghrelin and IGF-1 serum concentrations throughout the lactation period in AR pups. At pnd7, the maternal rearing (MR) pups responded to a 4 h fast with a drop in GH serum concentration, which is a well-known response to maternal deprivation. GH serum levels in the AR pups did not change, suggesting an adaptation phenomenon. A dopamine inhibitory effect of GH secretion was observed in pnd7 cultured somatotropes, suggesting dopamine regulation of GH secretion at this age. Acylated ghrelin serum levels in the AR pups showed an inverted pattern compared to that in the MR pups, which was related to the artificial feeding pattern. IGF-1 serum levels were lower in the AR pups than in MR pups, which was associated with hepatic GH resistance and with low Igf1 mRNA expression at pnd7. Interestingly, at pnd14, both pup groups showed high hepatic Igf1 mRNA expression but low IGF-1 serum levels, and this was inverted at pnd21. However, serum glucose levels were lower in the AR pups at pnd14 but reached the same levels as the MR pups at pnd21. Moreover, hepatomegaly and higher hepatic GH-receptor levels were observed in the AR pups at pnd21, which was in agreement with an absence of a solid food meal. During AR, the pups lost the maternal interaction-stimulated GH secretion, which correlated with lower IGF-1 serum levels during the first week of postnatal development. Later, the AR pups exhibited hepatic responses, in order to satisfy the metabolic demand for the normal weaning, with low carbohydrates levels in their meal.

3,5-T2 and 3,3',5-T3 Regulate Cerebellar Thyroid Hormone Signalling and Myelin Molecular Dynamics in Tilapia

In contrast to mammalian adults, myelination in teleosts occurs throughout their lifespan and most of the progenitor cells are originated in the cerebellum. To understand the role that thyroid hormones (THs) play in juvenile cerebellar myelination in teleosts, we identified and localised the expression of genes involved in TH signalling (mct8, oatp1c1, dio2, dio3, thraa and l-thrb1) and analysed the effects of the two bioactive THs, T2 and T3, upon their regulation, as well as upon some structural components of the myelination process. Ex vivo approaches using organotypic cerebellar cultures followed by FISH and qPCR showed gene-specific localisation and regulation of TH signalling genes in the cerebellar nuclei. In vivo approaches using methimazole (MMI)-treated juvenile tilapias replaced with low doses of T3 and T2 showed by immunofluorescence that myelin fibres in the cerebellum are more abundant in the granular layer and that their visible size is reduced after MMI treatment but partially restored with TH replacement, suggesting that low doses of TH promote the re-myelination process in an altered condition. Together, our data support the idea that T2 and T3 promote myelination via different pathways and prompt T2 as a target for further analysis as a promising therapy for hypomyelination.

Growth hormone promotes synaptogenesis and protects neuroretinal dendrites against kainic acid (KA) induced damage

There is increasing evidence that suggests a possible role for GH in retinal development and synaptogenesis. While our previous studies have focused largely on embryonic retinal ganglion cells (RGCs), our current study demonstrates that GH has a synaptogenic effect in retinal primary cell cultures, increasing the abundance of both pre- (SNAP25) and post- (PSD95) synaptic proteins. In the neonatal chick, kainate (KA) treatment was found to damage retinal synapses and abrogate GH expression. In response to damage, an increase in Cy3-GH internalization into RGCs was observed when administered shortly before or after damage. This increase in internalization also correlated with increase in PSD95 expression, suggesting a neuroprotective effect on the dendritic trees of RGCs and the inner plexiform layer (IPL). In addition, we observed the presence of PSD95 positive Müller glia, which may suggest GH is having a neuroregenerative effect in the kainate-damaged retina. This work puts forth further evidence that GH acts as a synaptogenic modulator in the chick retina and opens a new possibility for the use of GH in retinal regeneration research.

Administration of leuprolide acetate, a GnRH agonist, improves urodynamic parameters in ovariectomized rats

AIM

To evaluate the effects of a treatment with leuprolide acetate (LA) on bladder overactivity as well as the expression of gonadotropin releasing hormone receptor (GnRH-R), and neurofilaments NF68 and NF200 in female rats with overactive bladder induced by castration.

METHODS

Changes in the urodynamic parameters were determined in SHAM, ovariectomized (OVX) and ovariectomized rats treated with LA (OVX-LA). A semi-quantitative analysis for the expression pattern of GnRH-R and neurofilaments NF68 and NF200 were determined.

RESULTS

Forty-three days after ovariectomy, rats from the OVX group have significant lower values for intercontractile interval (ICI) and compliance (C); as well as higher values for basal bladder pressure (BP) and frequency of non-voiding contractions (NVC). The systemic application of LA increased voiding volume (Vv) and pressure threshold (ThP) in the OVX-LA animals. The application of LA reduced the high frequency of NVC in the OVX rats. No significant differences were found for Vv and NVCs between the OVX-LA vs SHAM groups. At the mid part of the bladder, the presence of GnRH-R was evidenced in the urothelium of the SHAM group. The OVX animals showed different pattern of immunolabeling for GnRH-R as well as for neurofilaments NF200 and NF68, whereas in the OVX-LA group the immunofluorescence pattern was similar to the one seen in SHAM bladders (P < 0.05 for OVX vs OVX + LA).

CONCLUSIONS

the results suggest that systemic application of LA can improve bladder dysfunction in castrated rats, and perhaps considered as a treatment for overactive bladder conditions secondary to menopause.

Expression of growth hormone gene in the baboon eye

The human growth hormone (GH) locus is comprised by two GH (GH1 and GH2) genes and three chorionic somatomammotropin (CSH1, CSH2 and CSH-L) genes. While GH1 is expressed in the pituitary gland, the rest are expressed in the placenta. However, GH1 is also expressed in several extrapituitary tissues, including the eye. So to understand the role of this hormone in the eye we used the baboon (Papio hamadryas), that like humans has a multigenic GH locus; we set up to investigate the expression and regulation of GH locus in adult and fetal baboon ocular tissues. We searched in baboon ocular tissues the expression of GH1, GH2, CSH1/2, Pit1 (pituitary transcription factor 1), GHR (growth hormone receptor), GHRH (growth hormone releasing hormone), GHRHR (growth hormone releasing hormone receptor), SST (somatostatin), SSTR1 (somatostatin receptor 1), SSTR2 (somatostatin receptor 2), SSTR3 (somatostatin receptor 3), SSTR4 (somatostatin receptor 4), and SSTR5 (somatostatin receptor 5) mRNA transcripts and derived proteins, by qPCR and immunofluorescence assays, respectively. The transcripts found were characterized by cDNA cloning and sequencing, having found only the one belonging to GH1 gene, mainly in the retina/choroid tissues. Through immunofluorescence assays the presence of GH1 and GHR proteins was confirmed in several retinal cell layers. Among the possible neuroendocrine regulators that may control local GH1 expression are GHRH and SST, since their mRNAs and proteins were found mainly in the retina/choroid tissues, as well as their corresponding receptors (GHRH and SSTR1-SSTR5). None of the ocular tissues express Pit1, so gene expression of GH1 in baboon eye could be independent of Pit1. We conclude that to understand the regulation of GH in the human eye, the baboon offers a very good experimental model.

Upregulation of GH, but not IGF1, in the hippocampus of the lactating dam after kainic acid injury

Lactation embodies a natural model of morphological, neurochemical, and functional brain plasticity. In this reproductive stage, the hippocampus of the female is less sensitive to excitotoxins in contrast to nulliparity. Growth hormone (GH) and insulin-like growth factor 1 (IGF1) are known to be neuroprotective in several experimental models of brain lesion. Here, activation of the GH-IGF1 pituitary-brain axis following kainic acid (7.5 mg/kg i.p. KA) lesion was studied in lactating and nulliparous rats. Serum concentrations of GH and IGF1 were uncoupled in lactation. Compared to virgin rats, the basal concentration of GH increased up to 40% but IGF1 decreased 58% in dams, and only GH increased further after KA treatment. In the hippocampus, basal expression of GH mRNA was higher (2.8-fold) in lactating rats than in virgin rats. GH mRNA expression in lactating rats increased further after KA administration in the hippocampus and in the hypothalamus, in parallel to GH protein concentration in the hippocampus of KA-treated lactating rats (43% vs lactating control), as detected by Western blot and immunofluorescence. Except for the significantly lower mRNA concentration in the liver of lactating rats, IGF1 expression was not altered by the reproductive condition or by KA treatment in the hippocampus and hypothalamus. Present results indicate upregulation of GH expression in the hippocampus after an excitotoxic lesion, suggesting paracrine/autocrine actions of GH as a factor underlying neuroprotection in the brain of the lactating dam. Since no induction of IGF1 was detected, present data suggest a direct action of GH.

Characterization and distribution of GHRH, PACAP, TRH, SST and IGF1 mRNAs in the green iguana

The somatotropic axis (SA) regulates numerous aspects of vertebrate physiology such as development, growth, and metabolism and has influence on several tissues including neural, immune, reproductive and gastric tract. Growth hormone (GH) is a key component of SA, it is synthesized and released mainly by pituitary somatotrophs, although now it is known that virtually all tissues can express GH, which, in addition to its well-described endocrine roles, also has autocrine/paracrine/intracrine actions. In the pituitary, GH expression is regulated by several hypothalamic neuropeptides including GHRH, PACAP, TRH and SST. GH, in turn, regulates IGF1 synthesis in several target tissues, adding complexity to the system since GH effects can be exerted either directly or mediated by IGF1. In reptiles, little is known about the SA components and their functional interactions. The aim of this work was to characterize the mRNAs of the principal SA components in the green iguana and to develop the tools that allow the study of the structural and functional evolution of this system in reptiles. By employing RT-PCR and RACE, the cDNAs encoding for GHRH, PACAP, TRH, SST and IGF1 were amplified and sequenced. Results showed that these cDNAs coded for the corresponding protein precursors of 154, 170, 243, 113, and 131 amino acids, respectively. Of these, GHRH, PACAP, SST and IGF1 precursors exhibited a high structural conservation with respect to its counterparts in other vertebrates. On the other hand, iguana's TRH precursor showed 7 functional copies of mature TRH (pyr-QHP-NH₂), as compared to 4 and 6 copies of TRH in avian and mammalian proTRH sequences, respectively. It was found that in addition to its primary production site (brain for GHRH, PACAP, TRH and SST, and liver for IGF1), they were also expressed in other peripheral tissues, i.e. testes and ovaries expressed all the studied mRNAs, whereas TRH and IGF1 mRNAs were observed ubiquitously in all tissues considered. These results show that the main SA components in reptiles of the Squamata Order maintain a good structural conservation among vertebrate phylogeny, and suggest important physiological interactions (endocrine, autocrine and/or paracrine) between them due to their wide peripheral tissue expression.

Growth hormone protects against kainate excitotoxicity and induces BDNF and NT3 expression in chicken neuroretinal cells

There is increasing evidence to suggest a beneficial neuroprotective effect of growth hormone (GH) in the nervous system. While our previous studies have largely focused on retinal ganglion cells (RGCs), we have also found conclusive evidence of a pro-survival effect of GH in cells of the inner nuclear layer (INL) as well as a protective effect on the dendritic trees of the inner plexiform layer (IPL) in the retina. The administration of GH in primary neuroretinal cell cultures protected and induced neural outgrowths. Our results, both in vitro (embryo) and in vivo (postnatal), showed neuroprotective actions of GH against kainic acid (KA)-induced excitotoxicity in the chicken neuroretina. Intravitreal injections of GH restored brain derived neurotrophic factor (BDNF) expression in retinas treated with KA. In addition, we demonstrated that GH over-expression and exogenous administration increased BDNF and neurotrophin-3 (NT3) gene expression in embryonic neuroretinal cells. Thus, GH neuroprotective actions in neural tissues may be mediated by a complex cascade of neurotrophins and growth factors which have been classically related to damage prevention and neuroretinal tissue repair.

Verbal fluency tests: Normative data for the Latin American Spanish speaking adult population

OBJECTIVE

To generate normative data for the Verbal Fluency Tests across 11 countries in Latin America, with country-specific adjustments for gender, age, and education, where appropriate.

METHOD

The sample consisted of 3,977 healthy adults who were recruited from Argentina, Bolivia, Chile, Cuba, El Salvador, Guatemala, Honduras, Mexico, Paraguay, Peru, and, Puerto Rico. Each subject was administered the Verbal Fluency Test as part of a larger neuropsychological battery. A standardized five-step statistical procedure was used to generate the norms.

RESULTS

The final multiple linear regression models for the letter F explained 8-30% of the variance, 7-32% for letter A, 8-32% for the letter S, and 16-43% for the animal category in Verbal Fluency Test scores. Although t-tests showed significant differences between men and women on the Verbal Fluency Test, they did not have an effect size larger than 0.3. As a result, gender-adjusted norms were not generated.

CONCLUSIONS

This is the first normative multicenter study conducted in Latin America aiming to create norms for the Verbal Fluency Test; this study will have important outcomes for the future of neuropsychology in the region.

Hopkins Verbal Learning Test- Revised: Normative data for the Latin American Spanish speaking adult population

OBJECTIVE

To generate normative data on the Hopkins Verbal Learning Test- Revised (HVLT-R) across 11 countries in Latin America, with country-specific adjustments for gender, age, and education, where appropriate.

METHOD

The sample consisted of 3,977 healthy adults who were recruited from Argentina, Bolivia, Chile, Cuba, El Salvador, Guatemala, Honduras, Mexico, Paraguay, Peru, and, Puerto Rico. Each subject was administered the HVLT-R as part of a larger neuropsychological battery. A standardized five-step statistical procedure was used to generate the norms.

RESULTS

The final multiple linear regression models explained 17- 45% of the variance in HVLT-R scores. Although t-tests showed significant differences between men and women in Guatemala on the HVLT-R, it was a small effect size. As a result, gender-adjusted norms were not generated.

CONCLUSIONS

The results from this study will have a substantial impact on the practice of neuropsychology in Latin America, as this is the first normative multicenter study to develop norms for the HVLT-R in this region.

Rey-Osterrieth Complex Figure - copy and immediate recall: Normative data for the Latin American Spanish speaking adult population

OBJECTIVE

To generate normative data on the Rey-Osterrieth Complex Figure Test (ROCF) across 11 countries in Latin America, with country-specific adjustments for gender, age, and education, where appropriate.

METHOD

The sample consisted of 3,977 healthy adults who were recruited from Argentina, Bolivia, Chile, Cuba, El Salvador, Guatemala, Honduras, Mexico, Paraguay, Peru, and, Puerto Rico. Each subject was administered the ROCF as part of a larger neuropsychological battery. A standardized five-step statistical procedure was used to generate the norms.

RESULTS

The final multiple linear regression models explained 7-34% of the variance in ROCF copy scores and 21-41% of the variance in immediate recall scores. Although t-tests showed significant differences between men and women on ROCF copy and immediate recall scores, none of the countries had an effect size larger than 0.3. As a result, gender-adjusted norms were not generated.

CONCLUSIONS

The present study is the first to create norms for the ROCF in Latin America. As a result, this study will have important implications for the formation and practice of neuropsychology in this region.

Internalization and synaptogenic effect of GH in retinal ganglion cells (RGCs)

In the chicken embryo, GH gene expression occurs in the neural retina and retinal GH promotes cell survival and induces axonal growth of retinal ganglion cells. Neuroretinal GH is therefore of functional importance before the appearance of somatotrophs and the onset of pituitary GH secretion to the peripheral plasma (at ED15-17). Endocrine actions of pituitary GH in the development and function of the chicken embryo eye are, however, unknown. This possibility has therefore been investigated in ED15 embryos and using the quail neuroretinal derived cell line (QNR/D). During this research, we studied for the first time, the coexistence of exogenous (endocrine) and local GH (autocrine/paracrine) in retinal ganglion cells (RGCs). In ovo systemic injections of Cy3-labeled GH demonstrated that GH in the embryo bloodstream was translocated into the neural retina and internalized into RGC's. Pituitary GH may therefore be functionally involved in retinal development during late embryogenesis. Cy3-labelled GH was similarly internalized into QNR/D cells after its addition into incubation media. The uptake of exogenous GH was by a receptor-mediated mechanism and maximal after 30-60min. The exogenous (endocrine) GH induced STAT5 phosphorylation and increased growth associated protein 43 (GAP43) and SNAP-25 immunoreactivity. Ex ovo intravitreal injections of Cy3-GH in ED12 embryos resulted in GH internalization and STAT5 activation. Interestingly, the CY3-labeled GH accumulated in perinuclear regions of the QNR/D cells, but was not found in the cytoplasm of neurite outgrowths, in which endogenous retinal GH is located. This suggests that exogenous (endocrine) and local (autocrine/paracrine) GH are both involved in retinal function in late embryogenesis but they co-exist in separate intracellular compartments within retinal ganglion cells.

Autocrine/paracrine proliferative effect of ovarian GH and IGF-I in chicken granulosa cell cultures

It is known that growth hormone (GH) and its receptor (GHR) are expressed in granulosa cells (GC) and thecal cells during the follicular development in the hen ovary, which suggests GH is involved in autocrine/paracrine actions in the female reproductive system. In this work, we show that the knockdown of local ovarian GH with a specific cGH siRNA in GC cultures significantly decreased both cGH mRNA expression and GH secretion to the media, and also reduced their proliferative rate. Thus, we analyzed the effect of ovarian GH and recombinant chicken GH (rcGH) on the proliferation of pre-hierarchical GCs in primary cultures. Incubation of GCs with either rcGH or conditioned media, containing predominantly a 15-kDa GH isoform, showed that both significantly increased proliferation as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, proliferating cell nuclear antigen (PCNA) quantification and ((3)H)-thymidine incorporation ((3)H-T) assays in a dose response fashion. Both, locally produced GH and rcGH also induced the phosphorylation of Erk1/2 in GC cultures. Furthermore, GH increased IGF-I synthesis and its release into the GC culture incubation media. These results suggest that GH may act through local IGF-I to induce GC proliferation, since IGF-I immunoneutralization completely abolished the GH-induced proliferative effect. These data suggest that GH and IGF-I may play a role as autocrine/paracrine regulators during the follicular development in the hen ovary at the pre-hierarchical stage.

Growth hormone reverses excitotoxic damage induced by kainic acid in the green iguana neuroretina

It is known that growth hormone (GH) is expressed in extrapituitary tissues, including the nervous system and ocular tissues, where it is involved in autocrine/paracrine actions related to cell survival and anti-apoptosis in several vertebrates. Little is known, however, in reptiles, so we analyzed the expression and distribution of GH in the eye of green iguana and its potential neuroprotective role in retinas that were damaged by the intraocular administration of kainic acid (KA). It was found, by Western blotting, that GH-immunoreactivity (GH-IR) was expressed as two isoforms (15 and 26kDa, under reducing conditions) in cornea, vitreous, retina, crystalline, iris and sclera, in varying proportions. Also, two bands for the growth hormone receptor (GHR)-IR were observed (70 and 44kDa, respectively) in the same tissues. By immunofluorescence, GH-IR was found in neurons present in several layers of the neuroretina (inner nuclear [INL], outer nuclear [ONL] and ganglion cell [GCL] layers) as determined by its co-existence with NeuN, but not in glial cells. In addition, GH and GHR co-expression was found in the same cells, suggesting paracrine/autocrine interactions. KA administration induced retinal excitotoxic damage, as determined by a significant reduction of the cell density and an increase in the appearance of apoptotic cells in the INL and GCL. In response to KA injury, both endogenous GH and Insulin-like Growth Factor I (IGF-I) expression were increased by 70±1.8% and 33.3±16%, respectively. The addition of exogenous GH significantly prevented the retinal damage produced by the loss of cytoarchitecture and cell density in the GCL (from 4.9±0.79 in the control, to 1.45±0.2 with KA, to 6.35±0.49cell/mm(2) with KA+GH) and in the INL (19.12±1.6, 10.05±1.9, 21.0±0.8cell/mm(2), respectively) generated by the long-term effect of 1mM KA intraocular administration. The co-incubation with a specific anti-GH antibody, however, blocked the protective effect of GH in GCL (1.4±0.23cell/mm(2)) and INL (11.35±1.06), respectively. Furthermore, added GH induced an increase of 90±14% in the retinal IGF-I concentration and the anti-GH antibody also blocked this effect. These results indicate that GH and GHR are expressed in the iguana eye and may be able to exert, either directly of mediated by IGF-I, a protective mechanism in neuroretinas that suffered damage by the administration of kainic acid.

Growth hormone in the eye: A comparative update

Comparative studies have previously established that the eye is an extrapituitary site of growth hormone (GH) production and action in fish, amphibia, birds and mammals. In this review more recent literature and original data in this field are considered.

Neuroprotection by GH against excitotoxic-induced cell death in retinal ganglion cells

Retinal growth hormone (GH) has been shown to promote cell survival in retinal ganglion cells (RGCs) during developmental waves of apoptosis during chicken embryonic development. The possibility that it might also against excitotoxicity-induced cell death was therefore examined in the present study, which utilized quail-derived QNR/D cells as an in vitro RGC model. QNR/D cell death was induced by glutamate in the presence of BSO (buthionine sulfoxamide) (an enhancer of oxidative stress), but this was significantly reduced (P<0.01) in the presence of exogenous recombinant chicken GH (rcGH). Similarly, QNR/D cells that had been prior transfected with a GH plasmid to overexpress secreted and non-secreted GH. This treatment reduced the number of TUNEL-labeled cells and blocked their release of lactate dehydrogenase (LDH). In a further experiment with dissected neuroretinal explants from ED (embryonic day) 10 embryos, rcGH treatment of the explants also reduced (P<0.01) the number of glutamate-BSO-induced apoptotic cells and blocked the explant release of LDH. This neuroprotective action was likely mediated by increased STAT5 phosphorylation and increased bcl-2 production, as induced by exogenous rcGH treatment and the media from GH-overexpressing QNR/D cells. As rcGH treatment and GH-overexpression cells also increased the content of IGF-1 and IGF-1 mRNA this neuroprotective action of GH is likely to be mediated, at least partially, through an IGF-1 mechanism. This possibility is supported by the fact that the siRNA knockdown of GH or IGF-1 significantly reduced QNR/D cell viability, as did the immunoneutralization of IGF-1. GH is therefore neuroprotective against excitotoxicity-induced RGC cell death by anti-apoptotic actions involving IGF-1 stimulation.

Differential responses of the somatotropic and thyroid axes to environmental temperature changes in the green iguana

Growth hormone (GH), together with thyroid hormones (TH), regulates growth and development, and has critical effects on vertebrate metabolism. In ectotherms, these physiological processes are strongly influenced by environmental temperature. In reptiles, however, little is known about the direct influences of this factor on the somatotropic and thyroid axes. Therefore, the aim of this study was to describe the effects of both acute (48h) and chronic (2weeks) exposure to sub-optimal temperatures (25 and 18°C) upon somatotropic and thyroid axis function of the green iguana, in comparison to the control temperature (30-35°C). We found a significant increase in GH release (2.0-fold at 25°C and 1.9-fold at 18°C) and GH mRNA expression (up to 3.7-fold), mainly under chronic exposure conditions. The serum concentration of insulin-like growth factor-I (IGF-I) was significantly greater after chronic exposure (18.5±2.3 at 25°C; 15.92±3.4 at 18°C; vs. 9.3±1.21ng/ml at 35°C), while hepatic IGF-I mRNA expression increased up to 6.8-fold. Somatotropic axis may be regulated, under acute conditions, by thyrotropin-releasing hormone (TRH) that significantly increased its hypothalamic concentration (1.45 times) and mRNA expression (0.9-fold above control), respectively; and somatostatin (mRNA expression increased 1.0-1.2 times above control); and under chronic treatment, by pituitary adenylate cyclase-activating peptide (PACAP mRNA expression was increased from 0.4 to 0.6 times). Also, it was shown that, under control conditions, injection of TRH stimulated a significant increase in circulating GH. On the other hand, while there was a significant rise in the hypothalamic content of TRH and its mRNA expression, this hormone did not appear to influence the thyroid axis activity, which showed a severe diminution in all conditions of cold exposure, as indicated by the decreases in thyrotropin (TSH) mRNA expression (up to one-eight of the control), serum T4 (from 11.6±1.09 to 5.3±0.58ng/ml, after 2weeks at 18°C) and T3 (from 0.87±0.09 to 0.05±0.01ng/ml, under chronic conditions at 25°C), and Type-2 deiodinase (D2) activity (from 992.5±224 to 213.6±26.4fmolI(125)T4/mgh). The reduction in thyroid activity correlates with the down-regulation of metabolism as suggested by the decrease in the serum glucose and free fatty acid levels. These changes apparently were independent of a possible stress response, at least under acute exposure to both temperatures and in chronic treatment to 25°C, since serum corticosterone had no significant changes in these conditions, while at chronic 18°C exposure, a slight increase (0.38 times above control) was found. Thus, these data suggest that the reptilian somatotropic and thyroid axes have differential responses to cold exposure, and that GH and TRH may play important roles associated to adaptation mechanisms that support temperature acclimation in the green iguana.

[What is the true role of surgery in the infertility associated with endometriosis?]

BACKGROUND

Endometriosis is one of the most challenging clinical conditions for gynecologists. Associated pain and infertility are often difficult to manage, and current treatment strategies remain limited.

OBJECTIVE

This review reviews the current scientific evidence for general gynecologist and provides an overview of current information regarding the treatment of patients with endometriosis-related infertility, offering strong evidence to consider a less invasive approach, and highlights potential hazards of surgery within patients desiring to achieve a pregnancy.