Strontium enhances BMP-2 mediated bone regeneration in a femoral murine bone defect model.

The application of strontium is one option for the clinical treatment of osteoporosis-a disease characterized by reduced bone density and quality-in order to reduce the risk of vertebral and nonvertebral fractures. Unlike other drugs used in osteoporosis therapy, strontium shows a dual effect on bone metabolism by attenuating cellular resorption and simultaneously enhancing new bone tissue formation. Current concerns regarding the systemic application of highly dosed strontium ranelate led to the development of strontium-modified scaffolds based on mineralized collagen (MCM) capable to release biologically active Sr2+ ions directly at the fracture site. In this study, we investigated the regenerative potential of these scaffolds. For in vitro investigations, human mesenchymal stromal cells were cultivated on the scaffolds for 21 days (w/ and w/o osteogenic supplements). Biochemical analysis revealed a significant promoting effect on proliferation rate and osteogenic differentiation on strontium-modified scaffolds. In vivo, scaffolds were implanted in a murine segmental bone defect model-partly additionally functionalized with the osteogenic growth factor bone morphogenetic protein 2 (BMP-2). After 6 weeks, bridging calluses were obtained in BMP-2 functionalized scaffolds; the quality of the newly formed bone tissue by means of morphological scores was clearly enhanced in strontium-modified scaffolds. Histological analysis revealed increased numbers of osteoblasts and blood vessels, decreased numbers of osteoclasts, and significantly enhanced mechanical properties. These results indicate that the combined release of Sr2+ ions and BMP-2 from the biomimetic scaffolds is a promising strategy to enhance bone regeneration, especially in patients suffering from osteoporosis. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:174-182, 2020.

Tracking Cell Transplants in Femoral Osteonecrosis with Magnetic Resonance Imaging: A Proof-of-Concept Study in Patients.

PURPOSE: Osteonecrosis is a devastating complication of high-dose corticosteroid therapy in patients with cancer. Core decompression for prevention of bone collapse has been recently combined with the delivery of autologous concentrated bone marrow aspirates. The purpose of our study was to develop an imaging test for the detection of transplanted bone marrow cells in osteonecrosis lesions. EXPERIMENTAL DESIGN: In a prospective proof-of-concept clinical trial (NCT02893293), we performed serial MRI studies of nine hip joints of 7 patients with osteonecrosis before and after core decompression. Twenty-four to 48 hours prior to the surgery, we injected ferumoxytol nanoparticles intravenously to label cells in normal bone marrow with iron oxides. During the surgery, iron-labeled bone marrow cells were aspirated from the iliac crest, concentrated, and then injected into the decompression track. Following surgery, patients received follow-up MRI up to 6 months after bone marrow cell transplantation. RESULTS: Iron-labeled cells could be detected in the access canal by a dark (negative) signal on T2-weighted MR images. T2* relaxation times of iron-labeled cell transplants were significantly lower compared with unlabeled cell transplants of control patients who were not injected with ferumoxytol (P = 0.02). Clinical outcomes of patients who received ferumoxytol-labeled or unlabeled cell transplants were not significantly different (P = 1), suggesting that the added ferumoxytol administration did not negatively affect bone repair. CONCLUSIONS: This immediately clinically applicable imaging test could become a powerful new tool to monitor the effect of therapeutic cells on bone repair outcomes after corticosteroid-induced osteonecrosis.

Treating Cough Due to Non-CF and CF Bronchiectasis With Nonpharmacological Airway Clearance: CHEST Expert Panel Report.

BACKGROUND: In bronchiectasis due to cystic fibrosis (CF) and other causes, airway clearance is one of the mainstays of management. We conducted a systematic review on airway clearance by using non-pharmacological methods as recommended by international guidelines to develop recommendations or suggestions to update the 2006 CHEST guideline on cough. METHODS: The systematic search for evidence examined the question, "Is there evidence of clinically important treatment effects for non-pharmacological therapies in cough treatment for patients with bronchiectasis?" Populations selected were all patients with bronchiectasis due to CF or non-CF bronchiectasis. The interventions explored were the non-pharmacological airway clearance therapies. The comparison populations included those receiving standard therapy and/or placebo. Clinically important outcomes that were explored were exacerbation rates, quality of life, hospitalizations, and mortality. RESULTS: In both CF and non-CF bronchiectasis, there were systematic reviews and overviews of systematic reviews identified. Despite these findings, there were no large randomized controlled trials that explored the impact of airway clearance on exacerbation rates, quality of life, hospitalizations, or mortality. CONCLUSIONS: Although the cough panel was not able to make recommendations, they have made consensus-based suggestions and provided direction for future studies to fill the gaps in knowledge.

The value of synchro-cystourethrometry for evaluating the relationship between urethral instability and overactive bladder.

PURPOSE: To investigate the correlation between urethral instability (URI) and overactive bladder (OAB) in children. METHODS: We retrospectively investigated 126 children with OAB and 36 children without OAB using synchro-cystourethrometry. The prevalence of detrusor overactivity (DO) and URI, and the diagnostic sensitivity of DO alone and DO combined with URI, was compared. The OAB children with URI voluntarily received transcutaneous electrical pudendal nerve stimulation with anisodamine (stimulation group, SG) or anisodamine alone (non-stimulation group, NSG). The effectiveness of treatment was evaluated. Average voided volume (AVV), maximum voided volume (MVV), and number of voids per day (NV) were collected and analyzed. RESULTS: In OAB children, the prevalence of DO and URI was 51.6 and 32.5%, respectively. The prevalence of URI was 5.6% in controls. The prevalence of URI was significantly higher in OAB children. The diagnostic sensitivity and Youden index of DO combined with URI were higher than DO alone. In SG, 45.7% of children were cured, with a ≥ 50% improvement rate of 82.9%, while no child was cured, with a ≥ 50% improvement rate of 36.8% in NSG. A significant increase in AVV and MVV together, with a decrease in NV, was seen in SG. There was a significant difference in visual analogue scale values between SG and NSG (P < 0.01). CONCLUSIONS: Urethral instability plays an essential role in the pathogenesis and progression of OAB in children. Synchro-cystourethrometry is a useful urodynamic technology to precisely diagnose OAB, and transcutaneous electrical pudendal nerve stimulation may be an effective treatment for OAB children induced by URI.

The Contribution of Social Media to Body Dissatisfaction, Eating Disorder Symptoms, and Anabolic Steroid Use Among Sexual Minority Men.

Social media has been associated with body dissatisfaction and eating disorder symptoms among young women and adolescent girls. However, despite notable evidence of susceptibility to body image pressures, it remains unknown whether these associations generalize to sexual minority men. A nationwide sample of 2,733 sexual minority men completed an online survey advertised to Australian and New Zealand users of a popular dating app. Participants answered questions about how frequently they used 11 different social media platforms in addition to questions about their dating app use, body image, eating disorder symptoms, and anabolic steroids. Facebook, Youtube, Instagram, and Snapchat were the most frequently used social media platforms. A pattern of small-sized and positive associations emerged between social media use and body dissatisfaction, eating disorder symptoms, and thoughts about using anabolic steroids. Facebook, Instagram, and Snapchat evidenced the strongest associations. The associations of social media use with both muscularity dissatisfaction and eating disorder symptoms were stronger for image-centric social media platforms (e.g., Instagram) than nonimage-centric platforms (e.g., Wordpress); no differences were observed for body fat dissatisfaction, height dissatisfaction, or thoughts about using anabolic steroids. Previously documented associations of social media use with body dissatisfaction and related variables among women and girls appear to generalize to sexual minority men. Social media platforms that more centrally involve imagery may be of greater concern than nonimage-centric platforms. Additional research with sexual minority men is needed to elucidate the distinctions between adaptive and maladaptive social media use in the context of body dissatisfaction, eating disorders, and anabolic steroid use.

Disruptions of the genes involved in lysine biosynthesis, iron acquisition, and secondary metabolisms affect virulence and fitness in Metarhizium robertsii.

Based on genomic analysis, polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) pathways account for biosynthesis of the majority of the secondary metabolites produced by the entomopathogenic fungus Metarhizium robertsii. To evaluate the contribution of these pathways to M. robertsii fitness and/or virulence, mutants deleted for mrpptA, the Sfp-type 4' phosphopantetheinyl transferase gene required for their activation were generated. ΔmrpptA strains were deficient in PKS and NRPS activity resulting in colonies that lacked the typical green pigment and failed to produce the nonribosomal peptides (destruxins, serinocylins, and the siderophores ferricrocin and metachelins) as well as the hybrid polyketide-peptides (NG-39x) that are all produced by the wild type (WT) M. robertsii. The ΔmrpptA colonies were also auxotrophic for lysine. Two other mutant strains were generated: ΔmraarA, in which the α-aminoadipate reductase gene critical for lysine biosynthesis was disrupted, and ΔmrsidA, in which the L-ornithine N5-oxygenase gene that is critical for hydroxamate siderophore biosynthesis was disrupted. The phenotypes of these mutants were compared to those of ΔmrpptA to separate effects of the loss of lysine or siderophore production from the overall effect of losing all polyketide and non-ribosomal peptide production. Loss of lysine biosynthesis marginally increased resistance to H2O2 while it had little effect on the sensitivity to the cell wall disruptor sodium dodecyl sulfate (SDS) and no effect on sensitivity to iron deprivation. In contrast, combined loss of metachelin and ferricrocin through the inactivation of mrsidA resulted in mutants that were as hypersensitive or slightly more sensitive to H2O2, iron deprivation, and SDS, and were either identical or marginally higher in ΔmrpptA strains. In contrast to ΔmrpptA, loss of mrsidA did not completely abolish siderophore activity, which suggests the production of one or more non-hydroxamate iron-chelating compounds. Deletion of mrpptA, mrsidA, and mraarA reduced conidium production and conidia of a GFP-tagged ΔmrpptA strain displayed a longer germination delay than WT on insect cuticles, a deficiency that was rescued by lysine supplementation. Compared with WT, ΔmrpptA strains displayed ∼19-fold reduction in virulence against Drosophila suzukii. In contrast, lysine auxotrophy and loss of siderophores accounted for ∼2 and ∼6-fold decreases in virulence, respectively. Deletion of mrpptA had no significant effect on growth inhibition of Bacillus cereus. Our results suggest that PKS and NRPS metabolism plays a significant role in M. robertsii virulence, depresses conidium production, and contributes marginally to resistance to oxidative stress and iron homeostasis, but has no significant antibacterial effect.

Complementary and alternative healthcare use by participants in the PACE trial of treatments for chronic fatigue syndrome.

BACKGROUND: Chronic Fatigue Syndrome (CFS) is characterised by persistent fatigue, disability and a range of other symptoms. The PACE trial was randomised to compare four non-pharmacological treatments for patients with CFS in secondary care clinics. The aims of this sub study were to describe the use of complementary and alternative medicine (CAM) in the trial sample and to test whether CAM use correlated with an improved outcome. METHOD: CAM use was recorded at baseline and 52weeks. Logistic and multiple regression models explored relationships between CAM use and both patient characteristics and trial outcomes. RESULTS: At baseline, 450/640 (70%) of participants used any sort of CAM; 199/640 (31%) participants were seeing a CAM practitioner and 410/640 (64%) were taking a CAM medication. At 52weeks, those using any CAM fell to 379/589 (64%). Independent predictors of CAM use at baseline were female gender, local ME group membership, prior duration of CFS and treatment preference. At 52weeks, the associated variables were being female, local ME group membership, and not being randomised to the preferred trial arm. There were no significant associations between any CAM use and fatigue at either baseline or 52weeks. CAM use at baseline was associated with a mean (CI) difference of 4.10 (1.28, 6.91; p=0.024) increased SF36 physical function score at 52weeks, which did not reach the threshold for a clinically important difference. CONCLUSION: CAM use is common in patients with CFS. It was not associated with any clinically important trial outcomes.

The effect of SDF-1α on low dose BMP-2 mediated bone regeneration by release from heparinized mineralized collagen type I matrix scaffolds in a murine critical size bone defect model.

The treatment of critical size bone defects represents a challenge. The growth factor bone morphogenetic protein 2 (BMP-2) is clinically established but has potentially adverse effects when used at high doses. The aim of this study was to evaluate if stromal derived factor-1 alpha (SDF-1α) and BMP-2 released from heparinized mineralized collagen type I matrix (MCM) scaffolds have a cumulative effect on bone regeneration. MCM scaffolds were functionalized with heparin, loaded with BMP-2 and/or SDF-1α and implanted into a murine critical size femoral bone defect (control group, low dose BMP-2 group, low dose BMP-2 + SDF-1α group, and high dose BMP-2 group). After 6 weeks, both the low dose BMP-2 + SDF-1α group (5.8 ± 0.6 mm³, p = 0.0479) and the high dose BMP-2 group (6.5 ± 0.7 mm³, p = 0.008) had a significantly increased regenerated bone volume compared to the control group (4.2 ± 0.5 mm³). There was a higher healing score in the low dose BMP-2 + SDF-1α group (median grade 8; Q1-Q3 7-9; p = 0.0357) than in the low dose BMP-2 group (7; Q1-Q3 5-9) histologically. This study showed that release of BMP-2 and SDF-1α from heparinized MCM scaffolds allows for the reduction of the applied BMP-2 concentration since SDF-1α seems to enhance the osteoinductive potential of BMP-2. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2126-2134, 2016.

Reductive iron assimilation and intracellular siderophores assist extracellular siderophore-driven iron homeostasis and virulence.

Iron is an essential nutrient and prudent iron acquisition and management are key traits of a successful pathogen. Fungi use nonribosomally synthesized secreted iron chelators (siderophores) or reductive iron assimilation (RIA) mechanisms to acquire iron in a high affinity manner. Previous studies with the maize pathogen Cochliobolus heterostrophus identified two genes, NPS2 and NPS6, encoding different nonribosomal peptide synthetases responsible for biosynthesis of intra- and extracellular siderophores, respectively. Deletion of NPS6 results in loss of extracellular siderophore biosynthesis, attenuated virulence, hypersensitivity to oxidative and iron-depletion stress, and reduced asexual sporulation, while nps2 mutants are phenotypically wild type in all of these traits but defective in sexual spore development when NPS2 is missing from both mating partners. Here, it is reported that nps2nps6 mutants have more severe phenotypes than both nps2 and nps6 single mutants. In contrast, mutants lacking the FTR1 or FET3 genes encoding the permease and ferroxidase components, respectively, of the alternate RIA system, are like wild type in all of the above phenotypes. However, without supplemental iron, combinatorial nps6ftr1 and nps2nps6ftr1 mutants are less virulent, are reduced in growth, and are less able to combat oxidative stress and to sporulate asexually, compared with nps6 mutants alone. These findings demonstrate that, while the role of RIA in metabolism and virulence is overshadowed by that of extracellular siderophores as a high-affinity iron acquisition mechanism in C. heterostrophus, it functions as a critical backup for the fungus.

Discovery of an irreversible HCV NS5B polymerase inhibitor.

The discovery of lead compound 2e was described. Its covalent binding to HCV NS5B polymerase enzyme was investigated by X-ray analysis. The results of distribution, metabolism and pharmacokinetics were reported. Compound 2e was demonstrated to be potent (replicon GT-1b EC50 = 0.003 µM), highly selective, and safe in in vitro and in vivo assays.

Management of functional constipation in children with lower urinary tract symptoms: report from the Standardization Committee of the International Children's Continence Society.

PURPOSE: We present a consensus view of members of the International Children's Continence Society (ICCS) together with pediatric gastroenterologists, experts in the field of functional gastrointestinal disorders, on the management of functional constipation in children with lower urinary tract symptoms. MATERIALS AND METHODS: Discussions were held by the board of the ICCS and a multidisciplinary core group of authors was appointed. The draft document review process was open to all ICCS members via the website. Feedback was considered by the core authors and, by agreement, amendments were made as necessary. RESULTS: Guidelines on the assessment, and pharmacological and nonpharmacological management of functional constipation in children with lower urinary tract symptoms are outlined. CONCLUSIONS: The final document is not a systematic literature review. It includes relevant research when available, as well as expert opinion on the current understanding of functional constipation in children with lower urinary tract symptoms. The document is intended to be clinically useful in primary, secondary and tertiary care settings.

Pseudomonas syringae pv. tomato DC3000 CmaL (PSPTO4723), a DUF1330 family member, is needed to produce L-allo-isoleucine, a precursor for the phytotoxin coronatine.

Pseudomonas syringae pv. tomato DC3000 produces the phytotoxin coronatine, a major determinant of the leaf chlorosis associated with DC3000 pathogenesis. The DC3000 PSPTO4723 (cmaL) gene is located in a genomic region encoding type III effectors; however, it promotes chlorosis in the model plant Nicotiana benthamiana in a manner independent of type III secretion. Coronatine is produced by the ligation of two moieties, coronafacic acid (CFA) and coronamic acid (CMA), which are produced by biosynthetic pathways encoded in separate operons. Cross-feeding experiments, performed in N. benthamiana with cfa, cma, and cmaL mutants, implicate CmaL in CMA production. Furthermore, analysis of bacterial supernatants under coronatine-inducing conditions revealed that mutants lacking either the cma operon or cmaL accumulate CFA rather than coronatine, supporting a role for CmaL in the regulation or biosynthesis of CMA. CmaL does not appear to regulate CMA production, since the expression of proteins with known roles in CMA production is unaltered in cmaL mutants. Rather, CmaL is needed for the first step in CMA synthesis, as evidenced by the fact that wild-type levels of coronatine production are restored to a ΔcmaL mutant when it is supplemented with 50 µg/ml l-allo-isoleucine, the starting unit for CMA production. cmaL is found in all other sequenced P. syringae strains with coronatine biosynthesis genes. This characterization of CmaL identifies a critical missing factor in coronatine production and provides a foundation for further investigation of a member of the widespread DUF1330 protein family.

Phytotoxicity of antofine from invasive swallow-worts.

Pale swallow-wort (Vincetoxicum rossicum) and black swallow-wort (V. nigrum) are two emerging invasive plant species in the northeastern United States and southeastern Canada that have shown rapid population expansion over the past 20 years. Using bioassay-guided fractionation, the known phytochemical phenanthroindolizidine alkaloid, (-)-antofine, was identified as a potent phytotoxin in roots, leaves, and seeds of both swallow-wort species. In seedling bioassays, (-)-antofine, at µM concentrations, resulted in greatly reduced root growth of Asclepias tuberosa, A. syriaca, and Apocynum cannabinum, three related, native plant species typically found in habitats where large stands of swallow-wort are present. In contrast, antofine exhibited moderate activity against lettuce, and it had little effect on germination and root growth of either black or pale swallow-wort. In disk diffusion assays, antifungal activity was observed at 10 µg and 100 µg, while antibacterial activity was seen only at the higher level. Although both swallow-wort species display multiple growth and reproductive characteristics that may play an important role in their invasiveness, the presence of the highly bioactive phytochemical (-)-antofine in root and seed tissues indicates a potential allelopathic role in swallow-worts' invasiveness.

Long-term follow-up of patients after antegrade continence enema procedure.

BACKGROUND: Antegrade continence enema (ACE) has become an important therapeutic modality in the treatment of intractable constipation and fecal incontinence. There are little data available on the long-term performance of the ACE procedure in children. METHODS: A retrospective review of patients who underwent the ACE procedure was conducted. Irrigation characteristics and complications were noted. Outcome was assessed for individual encounters based on frequency of bowel movements, incontinence, pain, and predictability. RESULTS: One hundred seventeen patients underwent an ACE. One hundred five patients had at least 6 months of follow-up, and were included in the analysis. Diagnoses included myelodysplasia (39%), functional intractable constipation (26%), anorectal malformations (21%), nonrelaxing internal anal sphincter (7%), cerebral palsy (3%), and other diagnoses (4%). The average follow-up was 68 months (range 7-178 months). At the last follow-up, 69% of patients had successful bowel management. Of the 31% of patients who did not have successful bowel management, 20% were using the ACE despite suboptimal results, 10% required surgical removal, and 2% were not using the ACE because of behavioral opposition to it. Patients were started on normal saline, but were switched to GoLYTELY (PEG-3350 and electrolyte solution) if there was an inadequate response (61% at final encounter). Additives were needed in 34% of patients. The average irrigation dose was 23 ± 0.7 mL/kg. The average toilet sitting time was 51.7 ± 3.5 minutes, with infusions running for 12.1 ± 1.2 minutes. Stomal complications occurred in 63% (infection, leakage, and stenosis) of patients, 33% required surgical revision and 6% eventually required diverting ostomies. CONCLUSIONS: Long-term use of the ACE gives successful results in 69% of patients, whereas 63% had a stoma-related complication and 33% required surgical revision of the stoma.

Effects of systemic capsaicin treatment on TRPV1 and Tachykinin NK(1) receptor distribution and function in the nucleus of the solitary tract of the adult rat.

Vanilloids including capsaicin and resiniferatoxin (RTX) have been identified as potential novel anti-inflammatory and analgesic compounds. We have previously shown that systemic capsaicin administration to neonatal rats evokes profound long-term alterations in transient receptor potential vanilloid 1 (TRPV1)- and neurokinin 1 (NK(1)) receptor-mediated respiratory responses in the commissural nucleus of the solitary tract (cNTS). Whether this effect of capsaicin is unique to developmentally immature animals is unknown. Therefore, in the present study, we investigated the effects of systemic capsaicin administration to adult rats on NK(1) receptor binding sites, TRPV1 and NK(1) immunoreactivity and function in the cNTS. Microinjection of capsaicin (1 nmol) or RTX (75 pmol) into the cNTS of vehicle-pretreated rats produced a profound bradypnoea (maximum change: -45 breaths·min(-1)) and a small increase in tidal volume (VT). Similarly, microinjection of the selective NK(1) receptor agonists [Sar(9), Met(O(2))(11)]substance P (SP; 66 pmol) and septide (20 pmol) decreased respiratory frequency and increased VT. Thirteen to 18 days after systemic administration of capsaicin (125 mg·kg(-1) s.c.), the bradypnoeic responses to both capsaicin and RTX were absent (p < 0.05), indicative of sensory neuron ablation/desensitisation. Systemic capsaicin pretreatment significantly (p < 0.05) reduced the density of both [(125)I]Bolton-Hunter SP binding sites (NK(1) receptors) and NK(1) receptor immunoreactivity in the cNTS, but did not alter the respiratory responses evoked by microinjection of [Sar(9), Met(O(2))(11)]SP and septide into this region. These studies show that systemic capsaicin administration reduces NK(1) receptor density in the cNTS without adversely affecting NK(1) receptor function at this site. We speculate that adult rats may be more resistant than neonatal rats to the neuroplastic effects of systemic capsaicin administration.

Biofeedback training for lower urinary tract symptoms: factors affecting efficacy.

PURPOSE: Biofeedback therapy is a valuable modality in children with dysfunctional voiding. However, it is unclear what factors contribute to the outcome. To define who may or may not benefit from biofeedback therapy we reviewed our experience with this treatment. MATERIALS AND METHODS: We retrospectively reviewed the charts of 77 children referred between July 2005 and September 2008 for biofeedback therapy. An MR 20 Synergy trainer (Prometheus Group, Dover, New Hampshire) provided nonanimated and animated biofeedback. Uroflowmetry was performed at the start and end of each session. A total of 67 females and 10 males with a mean age of 9.0 years (range 4.8 to 18.2) comprised the cohort group. The primary referral diagnosis was nonfebrile urinary tract infection in 52 patients (67.5%), daytime and nighttime wetting in 47 (61%), voiding postponement in 14 (18.2%) and daytime incontinence in 10 (13%). Children were categorized by an outcome of success, improvement or failure. Results were analyzed using the chi-square, Fisher exact probability and Student t tests. RESULTS: Success, improvement and failure were achieved in 22 (26.8%), 29 (37.7%) and 26 cases (33.7%), respectively. Age and gender were not statistically significant predictors of outcome. A median of 3.0 sessions (range 1 to 8) was administered. Children with 3 or greater sessions were more likely to succeed (p <0.005). The improvement in urinary tract infections was statistically significant (p <0.001). Of 37 children 20 (54%) transformed a staccato voiding pattern to a normal one on uroflowmetry. CONCLUSIONS: Biofeedback therapy can be effective in children with dysfunctional voiding and urinary tract infection. Children with a staccato voiding pattern may require a minimum of 3 visits to improve the voiding pattern. Children who complete 3 sessions are more likely to succeed.

Extracellular adenosine 5'-triphosphate alters motility and improves the fertilizing capability of mouse sperm.

Extracellular adenosine 5'-triphosphate (ATPe) treatment of human sperm has been implicated in improving in vitro fertilization (IVF) results. We used the mouse model to investigate mechanisms of action of ATPe on sperm. ATPe treatment significantly enhanced IVF success as indicated by both rate of pronuclear formation and percentage cleavage to the 2-cell stage. However, ATPe did not increase the percentage of sperm undergoing spontaneous acrosomal exocytosis nor change the pattern of protein tyrosine phosphorylation normally observed in capacitated sperm. ATPe altered sperm motility parameters; in particular, both noncapacitated and capacitated sperm swam faster and straighter. The percentage of hyperactivated sperm did not increase in capacitated ATPe-treated sperm compared to control sperm. ATPe induced a rapid increase in the level of intracellular calcium that was inhibited by two distinct P2 purinergic receptor inhibitors, confirming that these receptors have an ionotropic role in sperm function. The observed motility changes likely explain, in part, the improved fertilizing capability when ATPe-treated sperm were used in IVF procedures and suggest a mechanism by which ATPe treatment may be beneficial for artificial reproductive techniques.