Distributed and specific encoding of sensory, motor, and decision information in the mouse neocortex during goal-directed behavior

Goal-directed behaviors involve coordinated activity in many cortical areas, but whether the encoding of task variables is distributed across areas or is more specifically represented in distinct areas remains unclear. Here, we compared representations of sensory, motor, and decision information in the whisker primary somatosensory cortex, medial prefrontal cortex, and tongue-jaw primary motor cortex in mice trained to lick in response to a whisker stimulus with mice that were not taught this association. Irrespective of learning, properties of the sensory stimulus were best encoded in the sensory cortex, whereas fine movement kinematics were best represented in the motor cortex. However, movement initiation and the decision to lick in response to the whisker stimulus were represented in all three areas, with decision neurons in the medial prefrontal cortex being more selective, showing minimal sensory responses in miss trials and motor responses during spontaneous licks. Our results reconcile previous studies indicating highly specific vs. highly distributed sensorimotor processing.

Efficacy of spongy xenogeneic scaffold loaded with simvastatin in the treatment of severe alveolar horizontal defect: A clinical and histological study

Background

Bone tissue engineering offers several advantages for repairing skeletal defects. In this study, we designed and fabricated a scaffold for bone tissue engineering in patients with horizontal alveolar defect.

Aim

The items included in the fabrication of the scaffold were xenogenic bone graft, gelatin as a substrate to improve the physical integrity of scaffold, and simvastatin to stimulate osteogenesis (10 mg per 1 g of xenograft).

Methods

Fourteen patients with a horizontal defect in the alveolar ridge were enrolled in the study. Seven patients underwent routinely guided bone regeneration (GBR) using xenogenic bone graft plus collagenous membrane, and seven patients were treated with the scaffolds. After four months of follow-up after surgery, both the scaffold and GBR groups were examined for changes in the width of alveolar ridge and histologically for the quantity of newly produced bone.

Results

The newly designed scaffold showed superior osteoconduction characteristics to routine GBR materials, which were used in this study. The difference in the quantity of the newly produced bone between the scaffold group and GBR group was significant and higher for the scaffold group. Regarding newly produced bone percentage, the scaffold group showed a mean of 20.93 and the GBR group presented a mean of 13.25% (P = 0.004). Also, the mean value for the duration of surgery for GBR was 45 minutes and for scaffold was 22 minutes, which was significantly lower in the scaffold group (P < 0.001).

Conclusions

The newly designed scaffold is a suitable treatment modality for bone tissue engineering.

Alpha-Lipoic Acid Supplementation for Male Partner of Couples with Recurrent Pregnancy Loss: A Post hoc analysis in Clinical Trial

BACKGROUND

Increased sperm DNA damage is known as one of the causes of recurrent pregnancy loss (RPL) which can be due to increased levels of oxidative stress. Therefore, the aim of this study was to assess the effect of alpha-lipoic acid (ALA) on sperm parameters and sperm functions in couples with a history of RPL.

MATERIALS AND METHODS

In this post hoc analysis in clinical trial study, a total of 37 couples with RPL (n=12 and n=25 for placebo and ALA groups, respectively) were considered. Men were treated with ALA (600 mg/day) or placebo for 80 days. Semen samples were acquired from the participants before initiation and after completion of the medication course and assessed regarding conventional sperm parameters, chromatin damage/integrity, intracellular oxidative stress, lipid peroxidation, and seminal antioxidant characteristics. Individuals were further followed up for twelve months for pregnancy occurrence and outcomes. Finally, after excluding patients with no history of RPL, the data was analyzed.

RESULTS

No significant differences were observed between the baseline measures of the aforementioned parameters except for seminal volume. After the intervention, the mean sperm DNA damage, protamine deficiency, and persisted histones were significantly lower in the ALA group than in placebo receivers (P<0.05). A decrease in the mean of seminal total antioxidant capacity (P=0.03), malondialdehyde (P=0.02), and sperm DNA damage (P=0.004) as well as an increase in sperm total motility (P=0.04) after treatment with ALA was noticed. In addition, the mean of protamine deficiency and persisted histones were declined post-ALA therapy (P=0.003 and 0.002, respectively). The percentage of spontaneous pregnancy in the ALA group (4 of 25 cases; 16%) was higher than in the placebo group (1 of 12, 8.3%).

CONCLUSION

ALA-therapy attenuates sperm DNA damage and lipid peroxidation while enhancing sperm total motility and chromatin compaction in the male partner of couples with PRL (registration number: IRCT20190406043177N1).

Beneficial effects of trehalose and gentiobiose on human sperm cryopreservation

The protection of human sperm during cryopreservation is of great importance to infertility. Recent studies have shown that this area is still a long way from its ultimate aim of maintaining the maximum viability of sperm in cryopreservation. The present study used trehalose and gentiobiose to prepare the human sperm freezing medium during the freezing-thawing. The freezing medium of sperm was prepared with these sugars, and the sperm were then cryopreserved. The viable cells, sperm motility parameters, sperm morphology, membrane integrity, apoptosis, acrosome integrity, DNA fragmentation, mitochondrial membrane potential, reactive oxygen radicals, and malondialdehyde concentration was evaluated using standard protocols. A higher percentage of the total and progressive motility, rate of viable sperm, cell membrane integrity, DNA and acrosome integrity, and mitochondrial membrane potential were observed in the two frozen treatment groups compared to the frozen control. The cells had less abnormal morphology due to treatment with the new freezing medium than the frozen control. The higher malondialdehyde and DNA fragmentation were significantly observed in the two frozen treatment groups than in the frozen control. According to the results of this study, the use of trehalose and gentiobiose in the sperm freezing medium is a suitable strategy for sperm freezing to improve its motion and cellular parameters.

Alpha-Lipoic Acid Ameliorates Sperm DNA Damage and Chromatin Integrity in Men with High DNA Damage: A Triple Blind Randomized Clinical Trial

OBJECTIVE

Evidence suggests the contributory role of oxidative stress (OS) to sperm DNA damage and eventually, male infertility. Antioxidant supplementation has exhibited favorable results regarding seminal OS, sperm DNA damage, and chromatin integrity. We aimed to evaluate the effect of alpha-lipoic acid (ALA) supplementation on semen analysis, sperm DNA damage, chromatin integrity, and seminal/intracellular OS in infertile men with high sperm DNA damage.

MATERIALS AND METHODS

In this randomized triple-blind placebo-controlled clinical trial study, we opted for a triple-blind controlled clinical trial design. Considering the study's inclusion criteria for the level of sperm DNA fragmentation (higher than the threshold of 30 and 15%), 70% of participants were selected for this clinical research study. Subjects were divided into case and control groups receiving oral ALA (600 mg/day) and placebo for eighty days, respectively. Sperm parameters and functional tests were examined and compared before and after treatment. The final sample size was 34 and 29 for ALA and placebo receivers, respectively.

RESULTS

No significant differences were observed about anthropometrics and baseline measures of semen analysis, DNA damage, OS, and chromatin integrity between the two groups. Conventional semen parameters were enhanced insignificantly in both groups (P>0.05). DNA damage decreased significantly in the ALA group, as per sperm chromatin structure assay (SCSA, P<0.001). Moreover, chromomycin A3 (CMA3) staining results indicated a decrease in nuclear protamine deficiency post-ALA therapy (P=0.004). Lipid peroxidation decreased significantly after treatment with ALA (P=0.003). Further, seminal antioxidant capacity/activity did not differ significantly in either of the groups (registration number: IRCT20190406043177N1).

CONCLUSION

An 80-day course of oral ALA supplementation (600 mg/day) alleviates sperm OS, DNA damage, and chromatin integrity in men with high sperm DNA damage.

Sublethal Xanthine Oxidase Stress Prefreezing of Bull Sperm Improves the Post-Thaw Functionality and Fertility Potential Parameters

Oxidative stress during cryopreservation causes mechanical, biochemical, and structural damage to the sperm, leading to lower viability and fertility potential. In recent years, a novel method based on the use of mild stress for preconditioning of sperm before cryopreservation has been applied to improve the quality of thawed sperm, although its molecular mechanism remains unknown. In this study, we investigated the protective effects of sublethal oxidative stress by xanthine oxidase (XO) on thawed bull sperm performance through modulations of mitochondrial uncoupling protein 2 (UCP2) expression. Semen samples were collected from six bulls, then mixed and divided into four aliquots: frozen control (XO-0) and frozen groups treated with different concentrations of XO, 0.01 μM (XO-0.01), 0.1 μM (XO-0.1), and 1 μM (XO-1). Thawed sperm were evaluated for motion parameters, viability, acrosome integrity, mitochondria activity, membrane integrity, and UCP2 expression. A significant increase of total motility and viability rate was observed in XO-0.1 compared with other frozen groups (p < 0.05). The highest percentage of progressive motility was in XO-0.01 and XO-0.1 compared with other groups (p < 0.05). Moreover, a significantly higher level of sperm mitochondrial membrane potential and membrane integrity was observed in XO-0.1 (p < 0.05). We also found the lowest percentage of sperm mitochondria activity in XO-1 (p < 0.05). In addition, the highest expression of UCP2 was observed in XO-1 (p < 0.05). Our findings suggest that stress preconditioning of bull sperm before cryopreservation can improve thawed sperm functions, which might be mediated through an increase of UCP2 expression.

Direct visualization of pre-protamine 2 detects protamine assembly failures and predicts ICSI success

Histone-to-protamine transition is an essential step in the generation of fully functional spermatozoa in various mammalian species. In human and mouse, one of the two protamine-encoding genes produces a precursor pre-protamine 2 (pre-PRM2) protein, which is then processed and assembled. Here we design an original approach based on the generation of pre-PRM2-specific antibodies to visualize the unprocessed pre-PRM2 by microscopy, flow cytometry and immunoblotting. Using mouse models with characterized failures in histone-to-protamine replacement, we show that pre-Prm2 retention is tightly linked to nucleosome disassembly. Additionally, in elongating/condensing spermatids, we observe that pre-Prm2 and transition protein are co-expressed spatiotemporally, and their physical interaction suggests that these proteins act simultaneously rather than successively during histone replacement. By using our anti-human pre-PRM2 antibody we also measured pre-PRM2 retention rates in the spermatozoa from 49 men of a series of infertile couples undergoing ICSI, which shed new light on the debated relation between pre-PRM2 retention and sperm parameters. Finally, by monitoring 2-pronuclei (2PN) embryo formation following ICSI, we evaluated the fertilization ability of the sperm in these 49 patients. Our results suggest that the extent of pre-PRM2 retention in sperm, rather than pre-PRM2 accumulation per se, is associated with fertilization failure. Hence, anti-pre-PRM2/pre-Prm2 antibodies are valuable tools which could be used in routine monitoring of sperm parameters in fertility clinics, as well as in experimental research programmes to better understand the obscure process of histone-to-protamine transition.

Rapid suppression and sustained activation of distinct cortical regions for a delayed sensory-triggered motor response

The neuronal mechanisms generating a delayed motor response initiated by a sensory cue remain elusive. Here, we tracked the precise sequence of cortical activity in mice transforming a brief whisker stimulus into delayed licking using wide-field calcium imaging, multiregion high-density electrophysiology, and time-resolved optogenetic manipulation. Rapid activity evoked by whisker deflection acquired two prominent features for task performance: (1) an enhanced excitation of secondary whisker motor cortex, suggesting its important role connecting whisker sensory processing to lick motor planning; and (2) a transient reduction of activity in orofacial sensorimotor cortex, which contributed to suppressing premature licking. Subsequent widespread cortical activity during the delay period largely correlated with anticipatory movements, but when these were accounted for, a focal sustained activity remained in frontal cortex, which was causally essential for licking in the response period. Our results demonstrate key cortical nodes for motor plan generation and timely execution in delayed goal-directed licking.

Cortical circuits for transforming whisker sensation into goal-directed licking

Animals can learn to use sensory stimuli to generate motor actions in order to obtain rewards. However, the precise neuronal circuits driving learning and execution of a specific goal-directed sensory-to-motor transformation remain to be elucidated. Here, we review progress in understanding the contribution of cortical neuronal circuits to a task in which head-restrained water-restricted mice learn to lick a reward spout in response to whisker deflection. We first examine 'innate' pathways for whisker sensory processing and licking motor control, and then discuss how these might become linked through reward-based learning, perhaps enabled by cholinergic-gated and dopaminergic-gated plasticity. The aim is to uncover the synaptically connected neuronal pathways that mediate reward-based learning and execution of a well-defined sensory-to-motor transformation.

Neuronal Correlates of Tactile Working Memory in Prefrontal and Vibrissal Somatosensory Cortex

Tactile working memory engages a broad network of cortical regions in primates. To assess whether the conclusions drawn from primates apply to rodents, we examined the vibrissal primary somatosensory cortex (vS1) and the prelimbic cortex (PL) in a delayed comparison task. Rats compared the speeds of two vibrissal vibrations, stimulus1 and stimulus2, separated by a delay of 2 s. Neuronal firing rates in vS1 and PL encode both stimuli in real time. Across the delay, the stimulus1 representation declines more precipitously in vS1 than in PL. Theta-band local field potential (LFP) coherence between vS1 and PL peaks at trial onset and remains elevated during the interstimulus interval; simultaneously, vS1 spikes become phase locked to PL LFP. Phase locking is stronger on correct (versus error) trials. Tactile working memory in rats appears to be mediated by a posterior (vS1) to anterior (PL) flow of information, with performance facilitated through coherent LFP oscillation.

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Rats compared the speeds of two sequential vibrissal vibrations, separated by 2 s

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Neurons in the primary somatosensory (vS1) and prelimbic (PL) cortex coded the stimuli

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Theta local field potential coherence between vS1 and PL peaked at trial onset

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Intracortical coherent oscillations may play a role in rat tactile working memory

Intense and unpredictable perturbations during gait training improve dynamic balance abilities in chronic hemiparetic individuals: a randomized controlled pilot trial

Background

Previous studies have assessed the effects of perturbation training on balance after stroke. However, the perturbations were either applied while standing or were small in amplitude during gait, which is not representative of the most common fall conditions. The perturbations were also combined with other challenges such as progressive increases in treadmill speed.

Objective

To determine the benefit of treadmill training with intense and unpredictable perturbations compared to treadmill walking-only training for dynamic balance and gait post-stroke.

Methods

Twenty-one individuals post-stroke with reduced dynamic balance abilities, with or without a history of fall and ability to walk on a treadmill without external support or a walking aid for at least 1 min were allocated to either an unpredictable gait perturbation (Perturb) group or a walking-only (NonPerturb) group through covariate adaptive randomization. Nine training sessions were conducted over 3 weeks. NonPerturb participants only walked on the treadmill but were offered perturbation training after the control intervention. Pre- and post-training evaluations included balance and gait abilities, maximal knee strength, balance confidence and community integration. Six-week phone follow-ups were conducted for balance confidence and community integration. Satisfaction with perturbation training was also assessed.

Results

With no baseline differences between groups (p > 0.075), perturbation training yielded large improvements in most variables in the Perturb (p < 0.05, Effect Size: ES > .46) group (n = 10) and the NonPerturb (p ≤ .089, ES > .45) group (n = 7 post-crossing), except for maximal strength (p > .23) in the NonPerturb group. Walking-only training in the NonPerturb group (n = 8, pre-crossing) mostly had no effect (p > .292, ES < .26), except on balance confidence (p = .063, ES = .46). The effects of the gait training were still present on balance confidence and community integration at follow-up. Satisfaction with the training program was high.

Conclusion

Intense and unpredictable gait perturbations have the potential to be an efficient component of training to improve balance abilities and community integration in individuals with chronic stroke. Retrospective registration: ClinicalTrials.gov. March 18th, 2020. Identifier: NCT04314830.

Inclusion of ovine enriched serum with vitamin E and polyunsaturated fatty acids in the freezing medium: a new strategy to improve human frozen-thawed sperm parameters

The objective was to evaluate the effect of inclusion of 2.5% and 5% ovine serum, enriched with vitamin E (Vit E) and fish oil (FO), in human sperm freezing medium. Serum samples were prepared from sixteen rams (n = 4) feeding on a without supplemented diet, and diets supplemented with Vit E, FO and Vit E + FO. Semen samples, from 60 normozoospermic men, were frozen in: (I) a commercial freezing medium (SpermFreeze™; control medium), (II) the commercial freezing medium containing foetal bovine serum, (III) the commercial freezing medium + nonenriched serum (serum group), (IV) the commercial freezing medium + Vit E enriched serum (Vit E group), (V) the commercial freezing medium + FO enriched serum (FO group) and (VI) the commercial freezing medium + Vit E + FO enriched serum (Vit E + FO group). Sperm total and progressive motility, morphology, viability and plasma membrane integrity were significantly higher (p ≤ .05) in Vit E and Vit E + FO groups compared with the control group. Mitochondrial membrane potential did not differ between treatments (p > .05). It was concluded that ovine serum enriched with vitamin E and vitamin E + FO improved the quality of human spermatozoa but enriched serum containing FO could not improve the sperm cryo-injuries.

The alteration of PLCζ protein expression in unexplained infertile and asthenoteratozoospermic patients: A potential effect on sperm fertilization ability

Failed oocyte activation has been observed in unexplained infertile (UI) and asthenoteratozoospermic (AT) men. The deficiency of phospholipase C-zeta (PLCζ) could be a possible reason for such failures and has not been studied yet. We investigated the expression and localization of PLCζ protein in the sperms of patients with UI and AT conditions. The relationships between PLCζ-related parameters with male age, sperm characteristics, DNA integrity, and cellular maturity were assessed. Semen samples were collected from fertile (n = 40), UI (n = 40), and AT (n = 40) men. Subsequently, semen analysis, DNA fragmentation, hyaluronic acid-binding ability, and PLCζ level along with its distribution were evaluated using computer-assisted sperm analyzer, sperm chromatin structure assay (SCSA), hyaluronic acid-binding assay (HBA), western blot analysis and immunofluorescence microscopy, respectively. Unlike SCSA, the values of HBA, and PLCζ expression were significantly reduced in UI and AT patients compared to fertile men, whereas no significant differences were observed among the experimental groups in terms of PLCζ localization patterns. The regression analysis also showed that HBA is the only variable associated with PLCζ levels. Furthermore, the correlation of male age with PLCζ localization in postacrosomal, equatorial, and acrosomal+postacrosomal+equatorial (A+PA+E) patterns, as well as the relation of normal morphology, with the (A+PA+E) pattern, remained in the regression model. Our findings indicated that reduced PLCζ level along with the increased DNA fragmentation and impaired maturation may be possible etiologies of decreased fertilization in the studied subjects.

Peroxisome Proliferator-Activated Receptors (PPARs) levels in spermatozoa of normozoospermic and asthenozoospermic men

Interest in the role of male factor in infertility continues to mount with defects related to sperm movement considered as one of the more severe forms of subfertility. The peroxisome proliferator-activated receptor gamma (PPARγ) primarily regulates the expression of target genes involved in energy control as well as lipid and glucose metabolism. Although the pivotal roles of these receptors on female fertility have been reported, there are limited studies addressing PPARs role(s) in the male. This study was designed to determine and compare PPARα, PPARβ and PPARγ mRNA expression in sperm cells of normozoospermic and asthenozoospermic men. In addition, flow cytometric analyses, immunofluorescence and western blot were used to evaluate PPARγ protein levels in spermatozoa. We have compared the sperm PPARs mRNA relative expression in 27 normozoospermic and 28 asthenozoospermic samples and monitored sperm PPARγ protein levels in 39 normozoospermic and 40 asthenozoospermic samples using flow cytometry. We have also assessed in a sub-group of seven normozoospermic and eight asthenozoospermic samples, PPARγ protein levels by western blotting. Relative expression of PPARγ mRNA in normozoospermic men was found to be significantly higher (P = 0.004) than in asthenozoospermic men while PPARα and PPARβ relative expression was similar in the two groups. Likewise, PPARγ showed a positive correlation with motility (r = 0.34; P < 0.05), sperm concentration (r = 0.33) and the percentage of progressive motile spermatozoa (r = 0.31). In agreement with the mRNA behavior, sperm PPARγ protein levels as measured by flow cytometry (P = 0.066) and western blot (P = 0.089) showed a tendency to be higher in normozoospermic than asthenozoospermic men. The present study proposes a link between PPARγ gene expression level and motility in human sperm.Abbreviations: PPARs: Peroxisome Proliferator-Activated Receptors; CASA: Computer Assisted Semen Analysis; TFA: Trans Fatty Acids; HTF: Human Tubal Fluid; PBS: Phosphate-Buffered Saline; PPP: Pentose Phosphate Pathway; PI3K: Phosphoinositide 3-Kinase; G6PDH: Glucose 6-Phosphate Dehydrogenase.

Dietary trans and saturated fatty acids effects on semen quality, hormonal levels and expression of genes related to steroid metabolism in mouse adipose tissue

Our objectives were to assess sperm alteration and adipose tissue (AT) genes expression related to steroid metabolism subsequent to fatty acids consumption. Twenty-nine mature male mice were divided into: fat diet (FD; n = 15) and the control group (n = 14). FD group was fed with low level of trans and saturated fatty acids source for 60 days. Sperm parameters, levels of hormones and the mRNA abundance of the target genes in AT were assessed. The sperm concentration, total and progressive motilities were lower in FD group compared to that of control (p < 0.01). Blood estradiol levels increased in FD (p < 0.001), whereas no significant difference was observed in testosterone. The mRNA levels of StAR, CYP11A1, CYP17A1, 17βHSD7 and 17βHSD12 in AT of FD were higher than those of the control (p < 0.05). In contrast, mRNA level of Cyp19a1 in FD was significantly (p < 0.05) lower than that of control. 17βHSD12 and 17βHSD7 (as oestrogenic genes) increased, while 17βHSD5 and 17βHSD3 (as androgenic genes) remained unchanged, indicating that dietary trans/saturated fatty acids affect AT genes expression. Probably, sperm parameters were altered by increment of expression level of genes involved in oestrogenic metabolism rather than those engaged in androgenic metabolism after fatty acids consumption.

Sperm cryopreservation: A review on current molecular cryobiology and advanced approaches

The cryopreservation of spermatozoa was introduced in the 1960s as a route to fertility preservation. Despite the extensive progress that has been made in this field, the biological and biochemical mechanisms involved in cryopreservation have not been thoroughly elucidated to date. Various factors during the freezing process, including sudden temperature changes, ice formation and osmotic stress, have been proposed as reasons for poor sperm quality post-thaw. Little is known regarding the new aspects of sperm cryobiology, such as epigenetic and proteomic modulation of sperm and trans-generational effects of sperm freezing. This article reviews recent reports on molecular and cellular modifications of spermatozoa during cryopreservation in order to collate the existing understanding in this field. The aim is to discuss current freezing techniques and novel strategies that have been developed for sperm protection against cryo-damage, as well as evaluating the probable effects of sperm freezing on offspring health.

Proteomic analysis and microtubule dynamicity of human sperm in electromagnetic cryopreservation

The proteomic changes, microtubule dynamicity, and quality parameters of human sperm were investigated during cryopreservation in an extremely low electromagnetic field (ELEF) condition. Semen samples were obtained from 210 healthy individuals with normospermia and then were divided into three experimental groups: fresh control, frozen control, and frozen ELEF group. Shotgun proteomics was performed to assess the identification of microtubule proteins of the sperm in experimental groups. Microtubule dynamicity, secondary, and tertiary structure modifications of tubulins, characteristics of transmission electron microscopy of sperm as well as sperm quality parameters were evaluated. The expression ratios of α- and β-tubulins were significantly increased after cryopreservation compared with fresh control while this ratio was not significantly different in frozen ELEF group. The expression ratio of tubulin polymerization-promoting protein was significantly decreased after cryopreservation compared with fresh control. The length, width, and the activity of microtubule, secondary, and tertiary structures of tubulins, motility, and the viability of the sperm were decreased in frozen control as compared with fresh control. The microtubule activity, secondary, and tertiary structures of sperm tubulin in frozen ELEF group were higher than frozen control. Transmission electron microscopy of microtubules showed that the size of the width and length of the microtubules in frozen ELEF group were greater than frozen control. Motility, viability, and reactive oxygen species levels were improved in frozen ELEF group when compared with frozen control. While the microtubule dynamicity of the sperm was affected by the cryopreservation, this trait was improved during the electromagnetic cryopreservation resulted in better motility and viability.

Reward-Based Learning Drives Rapid Sensory Signals in Medial Prefrontal Cortex and Dorsal Hippocampus Necessary for Goal-Directed Behavior

The neural circuits underlying learning and execution of goal-directed behaviors remain to be determined. Here, through electrophysiological recordings, we investigated fast sensory processing across multiple cortical areas as mice learned to lick a reward spout in response to a brief deflection of a single whisker. Sensory-evoked signals were absent from medial prefrontal cortex and dorsal hippocampus in naive mice, but developed with task learning and correlated with behavioral performance in mice trained in the detection task. The sensory responses in medial prefrontal cortex and dorsal hippocampus occurred with short latencies of less than 50 ms after whisker deflection. Pharmacological and optogenetic inactivation of medial prefrontal cortex or dorsal hippocampus impaired behavioral performance. Neuronal activity in medial prefrontal cortex and dorsal hippocampus thus appears to contribute directly to task performance, perhaps providing top-down control of learned, context-dependent transformation of sensory input into goal-directed motor output.

Effect of dietary fish oil supplementation on ram semen freeze ability and fertility using soybean lecithin- and egg yolk-based extenders

Ram semen cryopreservation is not efficient for artificial insemination in commercial herds. Beneficial effects of dietary fish oil have been evaluated for cryopreservation of ram semen in soybean lecithin (SL) and egg yolk (EY)-based extenders. A factorial study (two diets × two extenders) was used to analyze the effects of two diets supplemented with fish oil (n-3 fatty acid) or palm oil (saturated fatty acids; [SFAs]) to freeze ram semen in two extenders containing SL or EY. Motility characteristics, membrane integrity, abnormal morphology, mitochondria activity, acrosome integrity, apoptotic status, and fertilizing ability were assessed after freeze-thawing. Although diet had significant (P ≤ 0.05) effects on the quality parameters of frozen-thawed sperm, effects of extenders on these traits were not significant (P > 0.05). The higher significant (P ≤ 0.05) percentage of total motility and progressive motility were observed in n-3/SL (44.83 ± 1.56 and 28.33 ± 1.4) and n-3/EY (43.33 ± 1.56 and 28.50 ± 1.4) than SFA/SL (32.16 ± 1.56 and 14.00 ± 1.4) and SFA/EY (31.66 ± 1.56 and 12.66 ± 1.4) groups. Moreover, n-3/SL and n-3/EY produced the higher significant (P ≤ 0.05) percentage of membrane integrity of sperm (39.83 ± 1.4 and 37.33 ± 1.4) than SFA/SL and SFA/EY (29.83 ± 1.4 and 28.5 ± 1.4). For viability results, the higher significant percentage of live sperm was observed in n-3/SL and n-3/EY (43.16 ± 1.38 and 45.66 ± 1.38) than SFA/SL and SFA/EY (28.66 ± 1.38 and 27.5 ± 1.38). For fertility trials, n-3-based diets (n-3/SL and n-3/EY) improved significantly (P ≤ 0.05) pregnancy rate (44% and 46%), parturition rate (42% and 42%), and lambing rate (46% and 44%) compared with the SFA-based diets (SFA/SL and SFA/EY). No interaction effects have been found between diets and extenders (P > 0.05). It seems that dietary fish oil can improve the semen performance after freezing-thawing process and artificial insemination aside from type of extenders.

Fertility and flow cytometry study of frozen-thawed sperm in cryopreservation medium supplemented with soybean lecithin

Semen cryopreservation can provide genetic resources for a large number of females from a small number of superior males. Optimization of cryopreservation media to achieve the highest quality of post-thaw semen is crucial. Soybean lecithin has evaluated as a plant-based cryoprotectant for substitution of egg yolk in ram semen extender. Flow cytometric and fertility assessments were applied following cryopreservation procedure in two experimental groups (SL group: extender containing 1% w/v soybean lecithin and EY group: extender containing 20% v/v egg yolk). The higher percentage of live sperm and the lower percentage of dead sperm were obtained in SL (47.66 ± 1.38, 52.33 ± 1.69, respectively) extender compared to EY (41.16 ± 1.38, 58.83 ± 1.69). For motion characteristics, plasma membrane integrity, acrosome integrity and mitochondria activity, no significant difference was observed between SL and EY extenders. In artificial insemination experiment, there was no significant difference in pregnancy rate, lambing rate and twining rate between SL and EY extenders. It can be concluded that SL extender can be an efficient alternative extender to preserve ram sperm during cryopreservation procedure without adverse effects.

Extramedullary Plasmacytoma of the Oral Cavity in a Young Man: a Case Report

Extramedullary plasmacytomas are rare solitary soft tissue tumors that arise from proliferations of malignant transformed monoclonal plasma cells and can be diagnosed through biopsy and histopathologic examination. These lesions are closely associated with multiple myelomas, which should be ruled out in all these cases by necessary laboratory and radiographic examinations. A 25-year-old man was referred to our clinic with a rapidly-growing painless lesion measuring about 2.5×3×3 cm in the palatal side of the left maxillary second and third molar teeth. A diagnosis of solitary plasmacytoma was made on the basis of clinical, radiographic, and histopathological findings. Early diagnosis of extramedullary plasmacytomas is of great importance. Radiotherapy is the common modality of treatment with or without adjuvant chemotherapy. Progression to multiple myeloma is possible; thus, close follow-up of the patient is essential after completion of the therapeutic procedure.

Dietary Vitamin E Is More Effective than Omega-3 and Omega-6 Fatty Acid for Improving The Kinematic Characteristics of Rat Sperm

Objective

Although key roles for dietary vitamin E (VITE) and fatty acid (FA) in fertility have been confirmed, limited data are available on the effects of VITE alone, or a constant level of VITE supplemented by dietary omega-6 and omega-3 FAs in combination on male reproduction. Consequently in this paper, the effects of VITE, sunflower oil, fish oil and their combination on rat sperm were investigated.

Materials and Methods

We divided 50 mature male Wistar rats into 5 groups (n=10) in a experimental completely randomized design for eight weeks: i. Control (CTR): standard diet; ii. Vitamin E diet (VITE): 2 times greater than recommendations; iii. Sunflower oil group (n-6) [gavaged with 0.5 ml/day/rat sunflower oil+VITE diet]; iv. Fish oil group (n-3): [gavaged with 0.5 ml/day/rat fish oil+VITE diet] and v. n-3+n-6 group [gavaged with 0.3 ml fish oil/day/rat+0.2 ml sunflower oil/day/rat+VITE diet]. The sperm parameters were measured by computer assisted semen analyzer (CASA). All data were analyzed with SPSS software.

Results

Feed intake decreased in groups which were administered sunflower oil compared with the other groups (P<0.05). The groups which received only VITE or fish oil+VITE had a significantly higher concentration of sperm compared with the n-6+n-3 and CTR group (P<0.05). VITE and n-3 showed significant improved progressive motility compared to the CTR group, whereas the n-6 and n-6+n-3 groups were in the middle (P<0.05). The highest sperm kinematic parameters were observed in the VITE only group. There was no strong correlation between sperm parameters and blood lipid profiles.

Conclusion

Dietary VITE and fish oil+VITE can improve sperm quality. Our findings can be a focus for improvements in sperm quantity and motility in fertile animals using only dietary VITE.

Dietary fatty acids affect semen quality: a review

Mammalian spermatozoa are characterized by a high proportion of polyunsaturated fatty acids (PUFA) which play a crucial role in fertilization. This review focuses on analysis of sperm fatty acid profiles and the effects of omega-3, saturated and trans dietary and sperm fatty acids on sperm parameters. Two major points have been pivotal points of investigation in the field of sperm fatty acid profiles: first, the comparison between fatty acid profiles of fertile and infertile men and second, the effect of dietary fatty acids on sperm fatty acid profiles as well as sperm quality and quantity. Docosahexaenoic acid (DHA, C22:6n-3), and palmitic acid (C16:0) are the predominant PUFA and saturated fatty acids, respectively, in human sperm cells. Higher levels of DHA are concentrated on the sperm's head or tail varying among different species. However, the human sperm head contains a higher concentration of DHA. Dietary fatty acids influence on sperm fatty acid profiles and it seems that sperm fatty acid profiles are most sensitive to dietary omega-3 PUFA. Although improvements in sperm parameters are a response to omega-3 sources after more than 4 weeks of supplementation in the male diet, time-dependent and dose-dependent responses may explain the failure in some experiments. In human spermatozoa, elevated saturated or trans fatty acid concentration and a low DHA level is a concern. The regulations of the sperm fatty acid mean melting point as well as expression regulation of peroxisome proliferator-activated receptor gamma (PPARG) alongside with spermatozoon assembly, anti-apoptosis effects, eicosanoid formation, and hormone activity are the putative key factors that induce a response by inclusion of omega-3 PUFA.

Effect of cysteine and glutamine added to extender on post-thaw sperm functional parameters of buffalo bull

Amino acids seem to be crucial components for semen freezing extender due to antioxidant properties. Therefore, this study aimed to assess motility parameters, membrane integrity, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP) and DNA damage to detect the optimum concentrations of cysteine and glutamine for buffalo semen cryopreservation. Twenty ejaculates of four buffalo bulls were diluted in tris-egg yolk extender and divided into seven equal groups consisting of cysteine (5, 7.5 and 10 mmol), glutamine (10, 15 and 20 mmol) and no additive. Supplementation of 5 and 7.5 mmol cysteine and 15 mmol glutamine in cryopreservation extender significantly increased post-thaw motility and plasma membrane integrity of spermatozoa with significant reduction in intracellular ROS when compared with control groups (P < 0.05). Cysteine at 7.5 mmol concentration elevated progressive motility and MMP, compared with control (P < 0.05). No significant differences were observed for motion patterns and DNA damage of frozen-thawed buffalo spermatozoa in extender containing amino acids. The findings of this study showed that supplementation of 7.5 mmol cysteine and 15 mmol glutamine in semen cryopreservation extender has more potential to decrease intracellular ROS, and subsequently elevate motility and membrane integrity of buffalo frozen-thawed spermatozoa.

Adverse effects of formaldehyde vapor on mouse sperm parameters and testicular tissue

BACKGROUND

Formaldehyde (FA), one of the simplest organic molecules, is a flammable, pungent, irritating and colorless gas. This study aimed to investigate the effects of various concentrations of FA vapor on sperm parameters and testicular tissue.

MATERIALS AND METHODS

In this experimental study, we randomly assigned 36 adult male mice to one control and two experimental groups (n=12 for each group). The control group (C) did not receive FA. Group F1 (low concentration) was exposed to 10 ppm FA vapor and the F2 (high concentration) group was exposed to 20 ppm FA vapor. FA was administered for ten days, eight hours per day for both groups. At the end of the exposure period, half of the animals in each group were sacrificed 24 hours after exposure to detect any short-term effects; the rest of the mice were sacrificed 35 days later to assess for long-term effects. Sperm parameters were analyzed by Computer-assisted Sperm Analyzer (CASA) and histological changes determined. In addition, we studied changes in testosterone hormone. Data were analyzed by one-way ANOVA followed by the Scheffe test using SPSS software.

RESULTS

Long-term effects of FA in the experimental groups included significant reductions in sperm cell numbers and sperm viability. A drastic reduction in progressive motility and increased abnormal sperm percentage (p<0.001) compared with the control group was also noted. Histological study of testes specimens in the experimental group revealed displacement of germinal cells, along with degeneration of Leydig cells and seminiferous tubules.

CONCLUSION

Exposure to FA vapor can destroy testicular structure and decrease percentages of concentration, viability, normal morphology, and progressive motility, in addition to increasing the percentage of immotile sperm.

Effect of tertiary-butyl hydroperoxide (TBHP)-induced oxidative stress on mice sperm quality and testis histopathology

Male infertility is responsible for approximately 50% of infertility worldwide. Reactive oxygen species are one of the major causes of male infertility. In this study, the effects of oxidative stress induced by tertiary-butyl hydroperoxide (TBHP) on sperm quality and testis tissue are investigated. After determination of LD50 , TBHP with a concentration of 1 : 10 LD50 was injected in adult male mice strains Balb/c for two consecutive weeks. Their testis tissues were used for cell viability, histopathology analysis and ROS assay. The epididymis was also surveyed for sperm analysis by CASA system. The sperm motility, count and viability decreased in the TBHP-treated mice compared to the control mice. The flow cytometry analysis showed a significant increase in H2 O2 and O2 ·- levels in both testis and sperm within 2 weeks after intraperitoneal injection. Body weights revealed no treatment-related effects, but atrophy of testis and a decrease of testis cells viability were observed. The results showed that exposure to TBHP could lead to morphological changes in seminiferous tubules. TBHP-induced oxidative stress caused a decrease in sperm parameters and testis cells viability. That is due to an increase level of ROS in the testis and their deleterious effects on genomic levels.

Fatty Acid Prof iles of Ram's Sperm after Removing Some Fatty Acid Sources from the Diets and Persistency of Fatty Acids in Sperm

BACKGROUND

Mammalian spermatozoa are characterized by a high proportion of polyunsaturated fatty acids (PUFAs), but reliable data concerning dietary effects on fatty acid (FA) profile in ram's sperm and the persistency of FA in the ration to the FA in sperm has not been reported. Therefore, the aim of this study was to determine the stability of saturated and unsaturated FAs in ram's sperm despite removing FA sources from their diet.

MATERIALS AND METHODS

Nine Kalkoohi rams were used in a completely randomized design and they were assigned to 3 groups. The treatments were diet supplemented (35 g/d/ram) by C16:0 (RP-10®), C18: 2 (Sunflower oil; SO) and n-3 (Fish oil; FO) with Vitamin E. Fifteen weeks after the start of the supplemented diet, rams were offered a basal diet without any supplementary FA source for 35 days when the sperm's FA ratio was determined. The data were analyzed by ANOVA (Analysis of variance) using the General Linear Model (GLM) procedure of SAS Institute.

RESULTS

THIRTY FIVE DAYS AFTER REMOVING THE FAT SUPPLEMENT FROM THE DIET, MAJOR FA IN SPERM CONSISTED OF: C14:0, C16:0, C18:0, C18:1 cis, C18:2 cis and C22:6 n-3 docosahexaenoic acid (DHA). The percentage of C14:0 (p=0.8) and C18:1 cis (P =0.4) were similar among all the treatments. Interestingly, 35 days after the removal of fatty acid source, the percentage of C22:6 was highest in the FO treated group.

CONCLUSION

The different sperm FA profile among various groups suggests that dietary FA had significant direct or indirect impacts on sperm FA profile after 35 days which might lead to physical and chemical changes in sperm characteristics.

Model system for measuring the effects of position and curvature of fiber reinforcement within a dental composite

PURPOSE

The aim of this study was to compare the effect of fiber curvature and position on flexural strength (FS), toughness, and elastic modulus in a dental flowable composite test specimen.

METHODS AND MATERIALS

Test specimens made of composite resin (Denfil Flow) were reinforced with preimpregnated glass fibers (Interlig). Control specimens (group A) did not contain fiber reinforcement. Fibers were placed with different positions and orientations into the test specimens (2 mm x 2 mm x 25 mm) (groups B, C, D). The test specimens (n = 10) were stored in distilled water for 3 days at 37 degrees C before testing in a three-point loading test (ISO 10477) at a crosshead speed of 1 mm/min to determine FS, flexural modulus (FM), and toughness. Data were analyzed with 1-way analysis of variance and Tukey HSD (sigma= 0.05).

RESULTS

The FM varied from 4.7 +/- 0.5 to 6.7 +/- 0.5 GPa. The lowest flexural strength and toughness values in reinforced specimens resulted from compression side fiber reinforcement (132 +/- 12 MPa, 21 +/- 4 MJ) and the highest from curved fiber reinforcement (174 +/- 8 MPa, 83 +/- 28 MJ), though this was not statistically significant from tension-side reinforcement. Although the toughness of the curved reinforced group was significantly higher than other groups, the flexural strength of curved reinforcement was not significantly higher than tension-side reinforcement.

CONCLUSION

Position and fiber orientation influenced the flexural strength, FM, and toughness. The most effective in increasing toughness was curved placement of fibers.

A novel ensemble strategy for classification of prostate cancer protein mass spectra

Protein mass spectra pattern recognition is a new forum in which many machine learning algorithms have been conducted to enhance the chance of early cancer diagnosis. The high-dimensionality-small-sample (HDSS) problem of cancer proteomic datasets still requires more sophisticated approaches to improve the classification accuracy. In this study we present a simple ensemble strategy based on measuring the generalizing capability of different subsets of training data and apply it in making final decision. Using a limited number of biomarkers along with 5 classification algorithms, the proposed method achieved a promising performance over a well-known prostate cancer mass spectroscopy dataset.

Classifying depth of anesthesia using EEG features, a comparison

Various EEG features have been used in depth of anesthesia (DOA) studies. The objective of this study was to find the excellent features or combination of them than can discriminate between different anesthesia states. Conducting a clinical study on 22 patients we could define 4 distinct anesthetic states: awake, moderate, general anesthesia, and isoelectric. We examined features that have been used in earlier studies using single-channel EEG signal processing method. The maximum accuracy (99.02%) achieved using approximate entropy as the feature. Some other features could well discriminate a particular state of anesthesia. We could completely classify the patterns by means of 3 features and Bayesian classifier.