Limited bedding and nesting increases ethanol drinking in female rats

Prenatal opioid exposure (POE) and postnatal adverse experiences are early life adversities (ELA) that often co-occur and increase problematic alcohol (EtOH) drinking during adolescence. We investigated the relationship between POE, postnatal adversity, and adolescent EtOH drinking in rats. We also sought to determine whether ELAs affect alpha-adrenoceptor density in the brain because the noradrenergic system is involved in problematic alcohol drinking and its treatment. We hypothesized that the combination of POE and postnatal adversity will increase alcohol drinking in rats compared to rats with exposure to either adversity alone or to control. We also predicted that POE and postnatal adversity would increase α1-adrenoceptor density and decrease α2-adrenoceptor density in brain to confer a stress-responsive phenotype. Pregnant rats received morphine (15 mg/kg/day) or saline via subcutaneous minipumps from gestational day 9 until birth. Limited bedding and nesting (LBN) procedures were introduced from postnatal day (PD) 3-11 to mimic early life adversity-scarcity. Offspring rats (PD 31-33) were given opportunities to drink EtOH (20 %, v/v) using intermittent-access, two-bottle choice (with water) procedures. Rats given access to EtOH were assigned into sub-groups that were injected with either yohimbine (1 mg/kg, ip) or vehicle (2 % DMSO, ip) 30 min prior to each EtOH access session to determine the effects of α2-adrenoceptor inhibition on alcohol drinking. We harvested cortices, brainstems, and hypothalami from EtOH-naïve littermates on either PD 30 or PD 70 and conducted radioligand receptor binding assays to quantify α1- and α2-adrenoceptor densities. Contrary to our hypothesis, only LBN alone increased EtOH intake in female adolescent rats compared to female rats with POE. Neither POE nor LBN affected α1- or α2-adrenoceptor densities in the cortex, brainstem, or hypothalamus of early- or late-aged adolescent rats. These results suggest a complex interaction between ELA type and sex on alcohol drinking.

Preaponeurotic endoscopic repair (REPA) indication in men could be controversial

PURPOSE

To evaluate the outcomes of REPA and establish if any differences in complications and evolution are present between males and females.

METHODS

A retrospective study including consecutive patients operated by REPA approach between November 2017 and April 2019 was conducted. Demographic data, operative times, postoperative complications, and hospital stay were analyzed. The EuraHS-QoL score was used to assess postoperative pain, daily activity constraints, and aesthetic discomfort. The results were compared between sexes. Statistical analysis was performed using SPSS 19.

RESULTS

Fifty-four patients were included and 53.7% were male. Patients had a mean age of 50.7 years and a mean BMI of 28.7. The average RAD (Rectus Abdominis Diastasis) size was 2.6 cm (range of 2-5 cm). Seroma was significantly more frequent in males, with an incidence of 55.2 and 24% for females (p = 0.02). Three cases required reintervention (5.5% of total cases), which corresponded to a cystic seroma, an abdominal wall hematoma, and a hernia recurrence. The three cases were males and a p value of 0.04 was obtained when comparing reintervention rates between males and females. No cases of surgical wound infection nor cutaneous necrosis were recorded. No conversions were needed. The mean postoperative pain was 2.25, the mean daily activity constraints score was 2.63, and the degree of aesthetic discomfort was 1.23 with no significant differences between groups.

CONCLUSION

The correction of small midline defect associated with minor RAD using REPA seems feasible and reproducible. REPA had achieved good results in females, but in males, the outcomes were poorer.

3225Global longitudinal strain measured using feature-tracking cardiac magnetic resonance imaging is an independent predictor of all cause mortality in patients with preserved ejection fraction

Introduction

Ejection fraction is the principal measure used clinically to assess cardiac mechanics and provides significant prognostic information. However, echocardiographic strain imaging has shown significant abnormalities of myocardial deformation can be present despite preserved ejection fraction, which maybe associated with adverse prognosis. Cardiac-Magnetic-Resonance (CMR) feature-tracking techniques now allow assessment of strain from routine cine-images, without specialized pulse sequences. Whether abnormalities of strain measured using CMR feature-tracking have prognostic value in patients with preserved ejection fraction is unknown.

Purpose

To evaluate the prognostic value of CMR feature-tracking derived global longitudinal strain (GLS) in a large multicenter population of patients with preserved ejection fraction.

Methods

Consecutive patients with preserved ejection fraction (EF ≥50%) and a clinical indication for CMR at four US medical centers were included in this study. Feature-tracking GLS was calculated from 3 long-axis-cine-views. The primary endpoint was all-cause death. Cox proportional hazards regression modeling was used to examine the independent association between GLS and death. The incremental prognostic value of GLS was assessed in nested models.

Results

Of the 1274 patients in this study, 115 died during a median follow-up of 6.2 years. By Kaplan-Meier analysis, patients with GLS ≥ median (−20%) had significantly reduced event free survival compared to those with GLS < median (log-rank p<0.001) (Figure, top panel). The continuous relationship between GLS and the hazard of death is shown in the cubic spline (Figure, lower panel). By Cox multivariable regression modeling, each 1% worsening in GLS was associated with a 23.6% increased risk-of-death after adjustment for clinical and imaging risk factors (HR=1.236 per %; p<0.001). Addition of GLS in this model resulted in significant-improvement in the global-chi-square (67 to 168; p<0.0001) and Harrel's C-statistic (0.716 to 0.825; p<0.0001).

Conclusions

CMR feature-tracking derived GLS is a powerful independent predictor of mortality in patients with preserved ejection fraction, incremental to common clinical and imaging risk factors.

CT Perfusion in Acute Lacunar Stroke: Detection Capabilities Based on Infarct Location

BACKGROUND AND PURPOSE

Recent studies demonstrated superiority of CTP to NCCT/CTA at detecting lacunar infarcts. This study aimed to assess CTP's capability to identify lacunae in different intracranial regions.

MATERIALS AND METHODS

Over 5.5 years, 1085 CTP examinations were retrospectively reviewed in patients with acute stroke symptoms with CTP within 12 hours and MRI within 7 days of symptom onset. Patients had infarcts ≤2 cm or no acute infarct on DWI; patients with concomitant infarcts >2 cm on DWI were excluded. CTP postprocessing was automated by a delay-corrected algorithm. Three blinded reviewers were given patient NIHSS scores and symptoms; infarcts were recorded based on NCCT/CTA, CTP (CBF, CBV, MTT, and TTP), and DWI.

RESULTS

One hundred thirteen patients met inclusion criteria (53.1% female). On DWI, lacunar infarcts were present in 37 of 113 (32.7%), and absent in 76 of 113 (67.3%). On CTP, lacunar infarcts typically appeared as abnormalities larger than infarct size on DWI. Interobserver κ for CTP ranged from 0.38 (CBF) (P < .0001) to 0.66 (TTP) (P < .0001); interobserver κ for DWI was 0.88 (P < 0.0001). In all intracranial regions, sensitivity of CTP ranged from 18.9% (CBV) to 48.7% (TTP); specificity ranged from 97.4% (CBF and TTP) to 98.7% (CBV and MTT). CTP's sensitivity was highest in the subcortical white matter with or without cortical involvement (21.7%-65.2%) followed by periventricular white matter (12.5%-37.5%); sensitivity in the thalami or basal ganglia was 0%.

CONCLUSIONS

CTP has low sensitivity and high specificity in identifying lacunar infarcts. Sensitivity is highest in the subcortical white matter with or without cortical involvement, but limited in the basal ganglia and thalami.

Defining acute ischemic stroke tissue pathophysiology with whole brain CT perfusion

BACKGROUND

This study aimed to identify and validate whole brain perfusion computed tomography (CTP) thresholds for ischemic core and salvageable penumbra in acute stroke patients and develop a probability based model to increase the accuracy of tissue pathophysiology measurements.

METHODS

One hundred and eighty-three patients underwent multimodal stroke CT using a 320-slice scanner within 6hours of acute stroke onset, followed by 24hour MRI that included diffusion weighted imaging (DWI) and dynamic susceptibility weighted perfusion imaging (PWI). Coregistered acute CTP and 24hour DWI was used to identify the optimum single perfusion parameter thresholds to define penumbra (in patients without reperfusion), and ischemic core (in patients with reperfusion), using a pixel based receiver operator curve analysis. Then, these results were used to develop a sigma curve fitted probability based model incorporating multiple perfusion parameter thresholds.

RESULTS

For single perfusion thresholds, a time to peak (TTP) of +5seconds best defined the penumbra (area under the curve, AUC 0.79 CI 0.74-0.83) while a cerebral blood flow (CBF) of < 50% best defined the acute ischemic core (AUC 0.73, CI 0.69-0.77). The probability model was more accurate at detecting the ischemic core (AUC 0.80 SD 0.75-0.83) and penumbra (0.85 SD 0.83-0.87) and was significantly closer in volume to the corresponding reference DWI (P=0.031).

CONCLUSIONS

Whole brain CTP can accurately identify penumbra and ischemic core using similar thresholds to previously validated 16 or 64 slice CTP. Additionally, a novel probability based model was closer to defining the ischemic core and penumbra than single thresholds.

Seizures induced by intracerebral administration of pyridoxal-5'-phosphate: effect of GABAergic drugs and glutamate receptor antagonists

Pyridoxal-5'-phosphate (PLP), the cofactor of glutamate decarboxylase, paradoxically induces convulsions when injected intracranially in adult mammals. We have tested the effect of some GABAergic and antiglutamatergic drugs on the behavioral and electroencephalographic (EEG) seizures produced by intracerebroventricular (i.c.v.) microinjection of 1 micromol PLP in the rat. PLP induced barrel turning, running fits and tonic-clonic convulsions, which started 5-10 min after recovery from the anesthesia (halothane), peaked at 20 min and disappeared at about 50 min. These symptoms were accompanied by frequent high amplitude EEG spike burst discharges. Pyridoxal, pyridoxamine-5'-phosphate or deoxypyridoxine were ineffective. The i.c.v. microinjection of the GABAergic compounds muscimol, isoguvacine, aminooxyacetic acid or GABA itself, significantly protected against PLP effects. In contrast, the NMDA receptor antagonists MK-801 and the non-NMDA receptor antagonist NBQX, failed to protect and induced motor alterations and mortality. We conclude that a temporary decrease of the GABA(A) receptor function is involved in the convulsant effect of PLP. This decrease might be due to the formation of a Schiff base between the carbonyl group of PLP and the epsilon-amino group of a functionally crucial lysine residue located in one extracellular loop of the GABA(A) receptor.

Biochemical characteristics of the gamma-aminobutyric acid system in the insulinoma cell lines HIT-T15, RIN-m5F, betaTC3, and comparison with rat brain

BACKGROUND

gamma-aminobutyric acid (GABA) is the most abundant inhibitory neurotransmitter in the mammalian brain. Both GABA and its synthesizing enzyme, L-glutamate decarboxylase (GAD), are also present in the insulin-secreting pancreatic beta cells, in which its physiologic role is unclear. We have studied several aspects of the GABA system in the insulinoma cell lines HIT-T15, RIN-m5F, and betaTC3 in comparison with rat brain tissue.

METHODS

Insulinoma cell lines and embryonic rat brain cortex neurons were cultured. GAD activity was determined by a radioenzymatic method and the presence of GAD(67) protein was assessed by immunocytochemistry. Amino acid content and the effect of different conditions on the release of endogenous GABA were measured by HPLC and fluorometric detection after o-phthaldialdehyde derivatization. [3H]GABA was used for measuring the uptake of the amino acid in the insulinoma cultures and in rat forebrain synaptosomes.

RESULTS

The three insulinoma lines possess GABA and GAD activity at levels of approximately 20% compared with adult rat brain cortex. Dissimilar from the latter, in insulinoma cultures enzyme activity was not enhanced by addition of an excess of the coenzyme pyridoxal-5'-phosphate. Immunocytochemical visualization of GAD showed that the cells in both neuronal cultures and insulinoma lines were GAD(67)-positive, similar to Purkinje cell somata of adult rat cerebellar cortex. [3H]GABA uptake in the cell lines was approximately 10% of that in rat forebrain synaptosomes and showed less ionic and temperature dependence. In both cultured cerebral neurons and RINm5F cells, the addition of arginine induced the release of GABA, whereas neither high K(+) concentration nor glucose had any effect.

CONCLUSIONS

The insulinoma cell lines studied possess the same GAD(67) form of the enzyme present in brain. RIN line cells are capable of transporting glutamate. In these cells as well as in cultured cortical neurons, arginine stimulates the release of GABA and glutamate probably as the result of its electrogenic transport. Insulinoma cell lines may therefore be useful to study GABA metabolism and function in pancreatic beta cells.

Indirect determination of stallion sperm capacitation based on esterase release from spermatozoa challenged with lysophosphatidylcholine

A spectrophotometric assay was developed to measure the amount of esterase released from stallion spermatozoa. This assay was used to determine the percentages of capacitated stallion spermatozoa, determined by the ability of spermatozoa to undergo an acrosome reaction and release esterase in response to a lysophosphatidylcholine challenge, for spermatozoa incubated under conditions to increase intracellular calcium and cAMP. Incubation with 100 nmol calcium ionophore A23187 l(-1) induced 66% of stallion spermatozoa to capacitate after 60 min of incubation at 37 degrees C. Subsequent experiments investigating the effects of compounds that increase intracellular cAMP concentrations, 8-bromo cAMP (8bcAMP) and isobutyl-methylxanthine (IBMX), revealed that A23187 in combination with IBMX capacitated stallion spermatozoa after incubation for 240 min, while the combination of A23187 + 8bcAMP + IBMX capacitated spermatozoa in 40 min at 37 degrees C. Treating spermatozoa with a combination of compounds that increase intracellular calcium (A23187) and cAMP (8bcAMP and IBMX) capacitate stallion spermatozoa and may provide an efficient method to capacitate stallion spermatozoa for in vitro fertilization procedures.

Decrease of glutamate decarboxylase activity after in vivo cortical infusion of gamma-aminobutyric acid

gamma-Aminobutyric acid (GABA) levels and the activity of glutamate decarboxylase were measured in homogenates of rat brain cortical tissue, at different times after chronic intracortical infusion of GABA in vivo during 2, 6 or 24 h. Cortical electrical activity was also recorded. As previously described, about 1 h after cessation of the infusion epileptic discharges were observed (GABA-withdrawal syndrome), which lasted for several days. At zero time after cessation of the infusion, before the appearance of seizures, GABA levels were increased 3-6-fold and glutamate decarboxylase activity was decreased 27-48% in the infused cortex, as compared to the contralateral cortex or to tissue from control intact rats. During epileptic discharges GABA levels gradually returned to normal values. In contrast, glutamate decarboxylase activity remained decreased during seizures and returned to normal only after recovery from the GABA-withdrawal syndrome. These results suggest that the persistent decrease in the activity of the decarboxylase is due probably to a lowered amount of the enzymatic protein, occurring as a consequence of a temporarily elevated intracellular GABA concentration. The decreased rate of GABA synthesis might be involved in the pathophysiology of the GABA-withdrawal syndrome.

Glutamate decarboxylase activity in the substantia nigra and the hippocampus of rats microinjected with inhibitors of the enzyme

Three inhibitors of glutamate decarboxylase (GAD), acting through different mechanisms, as well as pyridoxal phosphate (PLP), were microinjected unilaterally by stereotaxic procedures into the substantia nigra reticulata or the CA1 area of the hippocampus of the rat. The inhibitors used were thiosemicarbazide (TSC), gamma-glutamyl hydrazide and the PLP-glutamyl-hydrazone (PLPGH) formed by the combination of the latter with PLP. No behavioral alterations were observed after the administration of any of the drugs used, in any of the two brain regions studied. When measured in the absence of exogenous PLP, GAD activity in the substantia nigra injected with TSC was diminished by about 35%, and no changes were observed with the other drugs. In the CA1 hippocampal area both TSC and PLPGH inhibited GAD by more than 50%, and this inhibition was not reversed by PLP added in vitro. The results are discussed in terms of the possible explanation for the differences between the drugs used and for the lack of effects of GAD inhibition on the behavior of the animals.

Effect of tocopherol and taurine on membrane fluidity of retinal rod outer segments

The deficiency of taurine and alpha-tocopherol results in disturbances of the structure of retinal rod outer segments. In this study the effect of alpha-tocopherol (vitamin E) and taurine on the fluidity of membranes from frog retinal rod outer segments and of liposomes prepared with lecithin or with lipids from outer segment membranes was examined by steady-state fluorescence polarization of diphenyl-hexatriene (DPH). alpha-Tocopherol increased the DPH anisotropy parameter in both preparations. The vitamin modified the breakpoint temperature of Arrhenius plots of DPH anisotropy, and decreased the activation energy. Taurine failed to modify any of the parameters examined in both outer segment membranes and lecithin liposomes. These results suggest a stabilizer role for tocopherol in rod outer segment membranes. In contrast, the requirement of taurine to maintain outer segment structure seems unrelated to an effect on the physical state of membrane lipids.

Pharmacological identification of retinal cells releasing taurine by light stimulation

The effect of drugs blocking synaptic activity at different retinal levels was examined in this study, in an attempt to identify the origin of the light-stimulated release of 3H-taurine from the chick retina. It was determined by autoradiography that the chick retina accumulates taurine in photoreceptors, in cells from the inner nuclear layer, and in processes of the inner plexiform layer. All these are possible sites for the release of taurine upon illumination. To discriminate among these possibilities, the effects of aspartate, tetrodotoxin, strychnine, picrotoxin, chlorpromazine, tubocurarine, atropine, glutamate diethyl esther, alpha-amino adipate and 2-amino-4-phosphonobutyrate were studied. Aspartate (10 mM), which is known to eliminate the light response of cells postsynaptic to photoreceptors, induced a marked increase of 150% in the resting efflux of 3H-taurine but did not decrease significantly the light-stimulated release. Tetrodotoxin, which blocks amacrine cell responses, decreased 3H-taurine release stimulated by light by less than 20%. The efflux of taurine was unaffected by strychnine, picrotoxin, tubocurarine, atropine, chlorpromazine, and 2-amino-4-phosphonobutyrate, whereas it was increased by glutamate diethyl esther and alpha-amino adipate. These results, all together, point to photoreceptors as the cells releasing 3H-taurine in response to light.