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Roongroj Bhidayasiri - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of nocturnal Hypokinesia in parkinson s disease using a novel patient proxy questionnaire and correlations with objective monitoring
    Parkinsonism & Related Disorders, 2019
    Co-Authors: Roongroj Bhidayasiri, Jirada Sringean, Onanong Phokaewvarangkul, Pablo Martinezmartin, Chanawat Anan, Nitinan Kantachadvanich, Ray K Chaudhuri, Nobutaka Hattori
    Abstract:

    Abstract Background Nocturnal Hypokinesia is a decreased ability to perform sufficient axial rotation and/or trunk flexion to turn in or get out of bed. Currently, there are no validated questionnaires specifically to assess nocturnal Hypokinesia in PD patients. Objective To develop and validate a questionnaire to assess PD patients’ problems associated with turning or getting out of bed. Methods The nocturnal Hypokinesia questionnaire (NHQ) consists of 10 items, completed independently by patients and their caregivers. For validation, 76 patient-caregiver pairs completed the questionnaire and validity, agreement levels, and internal consistency assessed. In addition, 76 healthy couples served as controls. The NHQ and Modified Parkinson's Disease Sleep Scale (PDSS-2) were compared and 25 random patients-caregiver pairs were also assessed with objective night-time monitoring. Results Patient and caregiver scores showed a high level of agreement (Intra-class correlation: 0.84) with high internal consistency (KR-20 coefficient of 0.73 for patients and 0.69 for caregivers). No significant difference between the mean total NHQ scores as rated by patients and caregivers was observed. Mean NHQ scores from patients and caregivers were significantly higher than healthy controls (p  Conclusion The NHQ is a reliable instrument to identify symptoms of nocturnal Hypokinesia amongst PD patients. Strong patient-caregiver agreement supports the use of proxy evaluation by caregivers when patient's information is unobtainable.

  • getting a good night sleep the importance of recognizing and treating nocturnal Hypokinesia in parkinson s disease
    Parkinsonism & Related Disorders, 2018
    Co-Authors: Roongroj Bhidayasiri, Claudia Trenkwalder
    Abstract:

    When Parkinson's disease (PD) patients are asked about the quality of their sleep, their answers are dominated by difficulties associated with impaired mobility in bed, medically referred to as nocturnal Hypokinesia. Nocturnal Hypokinesia is symptomatic from the mid-stage of the disease, affecting up to 70% of PD patients, and contributes to poor sleep quality, and increased carer burden. Here we explore four areas of nocturnal Hypokinesia that are relevant to clinical practice, namely: manifestations and definition; clinical assessment and objective monitoring; etiologies and contributing factors; and evidence-based therapeutic approaches. In addition, we provide an operational definition of what constitutes nocturnal Hypokinesia and outline different methods of assessment, ranging from clinical interviews and rating scales to objective night-time monitoring with inertial sensors. Optimal management of nocturnal Hypokinesia in PD begins with recognizing its manifestation by inquiring about cardinal symptoms and contributing factors from, not only patients, but also carers, followed by formal assessment, and the application of individualized evidence-based treatment. Night-time dopaminergic treatment is the primary therapy; however, careful clinical judgment is required to balance the benefits with the potential adverse events related to nocturnal dopaminergic stimulation. Future studies are needed to explore the practicality of home-based objective assessment of nocturnal Hypokinesia, new therapeutic options not limited to dopaminergic medications, and non-pharmacologic approaches, including training on compensatory strategies and bedroom adaptations.

  • time for a strategy in night time dopaminergic therapy an objective sensor based analysis of nocturnal Hypokinesia and sleeping positions in parkinson s disease
    Journal of the Neurological Sciences, 2017
    Co-Authors: Jirada Sringean, Roongroj Bhidayasiri, Chusak Thanawattano, Chanawat Anan
    Abstract:

    Abstract Background Nocturnal Hypokinesia is a common night-time symptom in patients with Parkinson's disease (PD). However, there is still little understanding of the nature, and variations of severity of this symptom. Objectives To evaluate the severity of nocturnal Hypokinesia and sleep positions in PD patients using multisite wearable sensors. Methods Nocturnal parameters and sleep positions in 18 PD couples were assessed and compared using wearable sensors (limbs and trunk) for one night in their homes. Nocturnal parameters included number, velocity, acceleration, degree, limb movements and the number of times they got out of bed. Results PD patients had significantly fewer episodes of turns in bed than their spouses ( p  = 0.043), which was associated with significantly slower speed ( p  = 0.005), acceleration ( p  = 0.005) and fewer degrees ( p  = 0.017). When we split the night into the first and second half, significant findings were mainly demonstrated in the second half of the night, including significantly fewer turns ( p  = 0.02) with smaller degrees ( p  = 0.017), slower speed ( p  = 0.005) and acceleration ( p  = 0.007). No significant differences in these parameters were shown in the first half of the night except for smaller degrees of turn in bed in PD patients ( p  = 0.028) and slower acceleration ( p  = 0.037). In addition, PD patients spent significantly more time in a supine position compared to their spouses ( p  = 0.031) with significantly less time in a prone position ( p  = 0.041). Conclusion Nocturnal Hypokinesia gets worse as the night progresses. Treatment of nocturnal Hypokinesia should aim at providing a continuous dopaminergic delivery that can achieve a sustained therapeutic level of dopamine throughout the night.

  • quantitative demonstration of the efficacy of night time apomorphine infusion to treat nocturnal Hypokinesia in parkinson s disease using wearable sensors
    Parkinsonism & Related Disorders, 2016
    Co-Authors: Roongroj Bhidayasiri, Jirada Sringean, Chusak Thanawattano, Chanawat Anan, Kamolwan Boonpang, Ray K Chaudhuri
    Abstract:

    Abstract Background Nocturnal Hypokinesia/akinesia is one of the common night-time symptoms in patients with Parkinson's disease (PD), negatively affecting quality of life of patients and caregivers. The recognition of this problem and treatment options are limited in clinical practice. Objectives To evaluate the efficacy of nocturnal apomorphine infusion, using a wearable sensor, in patients who are already on daytime continuous subcutaneous apomorphine infusion and still suffer from nocturnal Hypokinesia. Methods Nocturnal parameters in 10 PD patients before and during nocturnal infusion were assessed over two nights at their homes, using a wearable sensor (trunk). Nocturnal parameters included number, velocity, acceleration, degree, and duration of rolling over, and number of times they got out of bed. Correlations with validated clinical rating scales were performed. Results Following nocturnal apomorphine infusion (34.8 ± 6.5 mg per night), there were significant improvements in the number of turns in bed (p = 0.027), turning velocity (p = 0.046), and the degree of turning (p = 0.028) in PD patients. Significant improvements of Modified Parkinson's Disease Sleep Scale (p = 0.005), the axial score of Unified Parkinson's Disease Rating Scale (p = 0.013), and Nocturnal Akinesia Dystonia and Cramp Scale (p = 0.014) were also observed. Conclusion Our study was able to demonstrate quantitatively the efficacy of nocturnal apomorphine infusion in PD patients with nocturnal Hypokinesia and demonstrated the feasibility of using wearable sensors to yield objective and quantifiable outcomes in a clinical trial setting. More studies are needed to determine the long-term efficacy of this treatment in a large prospective cohort of PD patients.

  • how well do parkinson s disease patients turn in bed quantitative analysis of nocturnal Hypokinesia using multisite wearable inertial sensors
    Parkinsonism & Related Disorders, 2016
    Co-Authors: Jirada Sringean, Roongroj Bhidayasiri, Chusak Thanawattano, Poonpak Taechalertpaisarn
    Abstract:

    Abstract Background Nocturnal Hypokinesia/akinesia is a distressing symptom in patients with Parkinson's disease (PD). However, it is difficult to accurately monitor these symptoms based on clinical interviews alone. Objectives To quantitatively compare nocturnal movements of PD patients with their spouses by using multisite inertial sensors and to correlate these parameters with disease severity scores. Methods Nocturnal movements in 19 PD couples (mild-moderate stage) were assessed and compared using wearable sensors (limbs and trunk) for one night at their homes. Nocturnal parameters included number, velocity, acceleration, degree, and duration of rolling over, number of getting out of bed, and limb movements. Each activity was compared to sleep diary, and video recording for accuracy. Results PD patients significantly had fewer rolling over (p = 0.048), turned with smaller degree (p = 0.007), less velocity (p = 0.011), and acceleration (p  Conclusion Our study was able to demonstrate quantitatively the presence of nocturnal Hypokinesia in PD patients. This problem correlated with daytime axial motor and nonmotor symptoms. Treatment strategy for PD should be based on a comprehensive review of both day- and nighttime symptoms.

Frederic Libersat - One of the best experts on this subject based on the ideXlab platform.

  • Parasitoid Jewel Wasp Mounts Multipronged Neurochemical Attack to Hijack a Host Brain
    Molecular & Cellular Proteomics, 2019
    Co-Authors: Ryan Arvidson, Maayan Kaiser, Jean Paul Urenda, Haroun Mohammed, Christopher Dail, Cebrina Nolan, Songqin Pan, Jason E Stajich, Sang-soo Lee, Frederic Libersat
    Abstract:

    The parasitoid emerald jewel wasp Ampulex compressa induces a compliant state of Hypokinesia in its host, the American cockroach Periplaneta americana through direct envenomation of the central nervous system (CNS). To elucidate the biochemical strategy underlying venom-induced Hypokinesia, we subjected the venom apparatus and milked venom to RNAseq and proteomics analyses to construct a comprehensive "venome", consisting of 264 proteins. Abundant in the venome are enzymes endogenous to the host brain, including M13 family metalloproteases, phospholipases, adenosine deaminase, hyaluronidase, and neuropeptide precursors. The amphipathic, alpha-helical ampulexins are among the most abundant venom components. Also prominent are members of the Toll/NF-κB signaling pathway, including proteases Persephone, Snake, Easter, and the Toll receptor ligand Spätzle. We find evidence that venom components are processed following envenomation. The acidic (pH~4) venom contains unprocessed neuropeptide tachykinin and corazonin precursors and is conspicuously devoid of the corresponding processed, biologically active peptides. Neutralization of venom leads to appearance of mature tachykinin and corazonin, suggesting that the wasp employs precursors as a prolonged time-release strategy within the host brain post-envenomation. Injection of fully processed tachykinin into host cephalic ganglia elicits short-term Hypokinesia. Ion channel modifiers and cytolytic toxins are absent in A. compressa venom, which appears to hijack control of the host brain by introducing a "storm" of its own neurochemicals. Our findings deepen understanding of the chemical warfare underlying host-parasitoid interactions and in particular neuromodulatory mechanisms that enable manipulation of host behavior to suit the nutritional needs of opportunistic parasitoid progeny.

  • a parasitoid wasp manipulates the drive for walking of its cockroach prey
    Current Biology, 2008
    Co-Authors: Ram Gal, Frederic Libersat
    Abstract:

    The parasitoid wasp A. compressa hunts cockroaches as a live food supply for its offspring. The wasp selectively injects venom into the cerebral ganglia of the prey to induce long-term Hypokinesia [1-5], during which the stung cockroach, although not paralyzed, does not initiate spontaneous walking and fails to escape aversive stimuli. This allows the wasp to grab the cockroach by the antenna and walk it to a nest much like a dog on a leash. There, the wasp lays an egg on the prey, seals the nest, and leaves. The stung cockroach, however, does not fight to escape its tomb but rather awaits its fate, being consumed alive by the hatching larva over several days. We investigated whether the venom-induced Hypokinesia is a result of an overall decrease in arousal or, alternatively, a specific decrease in the drive to initiate or maintain walking. We found that the venom specifically affects both the threshold for the initiation and the maintenance of walking-related behaviors. Nevertheless, the walking pattern generator itself appears to be intact. We thus report that the venom, rather than decreasing overall arousal, manipulates neuronal centers within the cerebral ganglia that are specifically involved in the initiation and maintenance of walking.

  • are monoaminergic systems involved in the lethargy induced by a parasitoid wasp in the cockroach prey
    Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2002
    Co-Authors: Aviva Weiseleichler, Frederic Libersat
    Abstract:

    The venom of the parasitoid wasp Ampulex compressa induces long-lasting Hypokinesia in the cockroach prey. Previous work indicates that the venom acts in the subesophageal ganglion to indirectly affect modulation of thoracic circuits for locomotion. However, the target of the venom in the subesophageal ganglion, and the mechanism by which the venom achieves its effects are as yet unknown. While the stung cockroaches appear generally lethargic, not all behaviors were affected, indicating that the venom targets specific motor systems and not behavior in general. Stung cockroaches were observed "freezing" in abnormal positions. Reserpine, which depletes monoamines, mimics the behavioral effects of the venom. We treated cockroaches with antagonists to dopamine and octopamine receptors, and found that the dopamine system is required for normal escape response. Dopamine injection induces prolonged grooming in normal cockroaches, but not in stung, suggesting that the venom is affecting dopamine receptors, or targets downstream of these receptors, in the subesophageal ganglion. This dopamine blocking effect fades slowly over the course of several weeks, similar to the time course of recovery from Hypokinesia. The similarity in the time courses suggests that the mechanism underlying the Hypokinesia may be the block of the dopamine receptors.

Samuel Z Goldhaber - One of the best experts on this subject based on the ideXlab platform.

  • prognostic role of echocardiography among patients with acute pulmonary embolism and a systolic arterial pressure of 90 mm hg or higher
    JAMA Internal Medicine, 2005
    Co-Authors: Nils Kucher, Elisa Rossi, Marisa De Rosa, Samuel Z Goldhaber
    Abstract:

    Background: The prognostic role of echocardiographic right ventricular (RV) dysfunction for predicting mortality in patients with acute pulmonary embolism and a preserved systemic arterial pressure remains controversial. Methods: We evaluated 1035 patients with pulmonary embolism from the International Cooperative Pulmonary Embolism Registry who (1) presented with systolic systemic arterial pressure of 90 mm Hg or higher and (2) who underwent echocardiography within 24 hours of a diagnosis of pulmonary embolism, showing presence (n=405) or absence (n=630) of RV hypokinesis. The main outcome measure was the cumulative survival rate through 30 days in patients with and without RV hypokinesis. Results:In patients with RV hypokinesis, the initial systolic systemic pressure was lower (125±22 mm Hg vs 131±22 mm Hg; P.001), and the initial heart rate was higher (104±21 beats per minute vs 99±22 beats per minute; P.001) than in patients without RV hypokinesis. Cancer was less often present (14.1% vs 22.5%, P=.001). The 30-day survival rates in patients with and withoutRVhypokinesiswere83.7%(95%confidenceinterval [CI], 79.3%-87.0%) and 90.6% (95% CI, 88.0%92.6%), respectively (log-rankP value.001). The univariate hazard ratio of RV hypokinesis for predicting 30daymortalitywas2.11(95%CI,1.41-3.16;P.001).Right ventricular hypokinesis remained an independent predictor of 30-day mortality (hazard ratio, 1.94; 95% CI, 1.23-3.06) after adjusting for univariately significant predictors, including cancer, congestive heart failure, chronic lung disease, age older than 70 years, systolic arterial pressure of 100 mm Hg or lower, administration of thrombolytic therapy, and heart rate greater than 100 beats per minutes. Conclusion: Among patients with pulmonary embolism who present with a systolic arterial pressure greater than or equal to 90 mm Hg, echocardiographic RV hypokinesis is an independent predictor of early death. Arch Intern Med. 2005;165:1777-1781

  • prognostic role of echocardiography among patients with acute pulmonary embolism and a systolic arterial pressure of 90 mm hg or higher
    JAMA Internal Medicine, 2005
    Co-Authors: Nils Kucher, Elisa Rossi, Marisa De Rosa, Samuel Z Goldhaber
    Abstract:

    Background: The prognostic role of echocardiographic right ventricular (RV) dysfunction for predicting mortality in patients with acute pulmonary embolism and a preserved systemic arterial pressure remains controversial. Methods: We evaluated 1035 patients with pulmonary embolism from the International Cooperative Pulmonary Embolism Registry who (1) presented with systolic systemic arterial pressure of 90 mm Hg or higher and (2) who underwent echocardiography within 24 hours of a diagnosis of pulmonary embolism, showing presence (n=405) or absence (n=630) of RV hypokinesis. The main outcome measure was the cumulative survival rate through 30 days in patients with and without RV hypokinesis. Results:In patients with RV hypokinesis, the initial systolic systemic pressure was lower (125±22 mm Hg vs 131±22 mm Hg; P.001), and the initial heart rate was higher (104±21 beats per minute vs 99±22 beats per minute; P.001) than in patients without RV hypokinesis. Cancer was less often present (14.1% vs 22.5%, P=.001). The 30-day survival rates in patients with and withoutRVhypokinesiswere83.7%(95%confidenceinterval [CI], 79.3%-87.0%) and 90.6% (95% CI, 88.0%92.6%), respectively (log-rankP value.001). The univariate hazard ratio of RV hypokinesis for predicting 30daymortalitywas2.11(95%CI,1.41-3.16;P.001).Right ventricular hypokinesis remained an independent predictor of 30-day mortality (hazard ratio, 1.94; 95% CI, 1.23-3.06) after adjusting for univariately significant predictors, including cancer, congestive heart failure, chronic lung disease, age older than 70 years, systolic arterial pressure of 100 mm Hg or lower, administration of thrombolytic therapy, and heart rate greater than 100 beats per minutes. Conclusion: Among patients with pulmonary embolism who present with a systolic arterial pressure greater than or equal to 90 mm Hg, echocardiographic RV hypokinesis is an independent predictor of early death. Arch Intern Med. 2005;165:1777-1781

  • prognostic significance of right ventricular hypokinesis and perfusion lung scan defects in pulmonary embolism
    American Heart Journal, 1994
    Co-Authors: Mark W Wolfe, Richard T Lee, Michael L Feldstein, Anthony J Parker, Patricia C Come, Samuel Z Goldhaber
    Abstract:

    We studied the relation between right ventricular (RV) hypokinesis on echocardiography and defects on the initial perfusion lung scan among 90 hemodynamically stable patients with pulmonary embolism (PE). Of the 90, 38 had qualitative evidence of RV hypokinesis, with a mean RV end-diastolic area significantly larger than those with normal RV wall motion (40.0 +/- 10.2 cm2 vs 20.1 +/- 6.4 cm2; p or = 0.3 appears to identify patients at increased risk for recurrent PE.

Ryan Arvidson - One of the best experts on this subject based on the ideXlab platform.

  • Parasitoid Jewel Wasp Mounts Multipronged Neurochemical Attack to Hijack a Host Brain
    Molecular & Cellular Proteomics, 2019
    Co-Authors: Ryan Arvidson, Maayan Kaiser, Jean Paul Urenda, Haroun Mohammed, Christopher Dail, Cebrina Nolan, Songqin Pan, Jason E Stajich, Sang-soo Lee, Frederic Libersat
    Abstract:

    The parasitoid emerald jewel wasp Ampulex compressa induces a compliant state of Hypokinesia in its host, the American cockroach Periplaneta americana through direct envenomation of the central nervous system (CNS). To elucidate the biochemical strategy underlying venom-induced Hypokinesia, we subjected the venom apparatus and milked venom to RNAseq and proteomics analyses to construct a comprehensive "venome", consisting of 264 proteins. Abundant in the venome are enzymes endogenous to the host brain, including M13 family metalloproteases, phospholipases, adenosine deaminase, hyaluronidase, and neuropeptide precursors. The amphipathic, alpha-helical ampulexins are among the most abundant venom components. Also prominent are members of the Toll/NF-κB signaling pathway, including proteases Persephone, Snake, Easter, and the Toll receptor ligand Spätzle. We find evidence that venom components are processed following envenomation. The acidic (pH~4) venom contains unprocessed neuropeptide tachykinin and corazonin precursors and is conspicuously devoid of the corresponding processed, biologically active peptides. Neutralization of venom leads to appearance of mature tachykinin and corazonin, suggesting that the wasp employs precursors as a prolonged time-release strategy within the host brain post-envenomation. Injection of fully processed tachykinin into host cephalic ganglia elicits short-term Hypokinesia. Ion channel modifiers and cytolytic toxins are absent in A. compressa venom, which appears to hijack control of the host brain by introducing a "storm" of its own neurochemicals. Our findings deepen understanding of the chemical warfare underlying host-parasitoid interactions and in particular neuromodulatory mechanisms that enable manipulation of host behavior to suit the nutritional needs of opportunistic parasitoid progeny.

  • ampulexins a new family of peptides in venom of the emerald jewel wasp ampulex compressa
    Biochemistry, 2018
    Co-Authors: Eugene L Moore, Ryan Arvidson, Jean Paul Urenda, Haroun Mohammed, Christopher N Banks, Elizabeth Duong, Michael E Adams
    Abstract:

    The parasitoid wasp Ampulex compressa injects venom directly into the brain and subesophageal ganglion of the cockroach Periplaneta americana, inducing a 7 to 10 day lethargy termed Hypokinesia. Hypokinesia presents as a significant reduction in both escape response and spontaneous walking. We examined aminergic and peptidergic components of milked venom with HPLC and MALDI-TOF mass spectrometry. HPLC coupled with electrochemical detection confirmed the presence of dopamine in milked venom, while mass spectrometry revealed that the venom gland and venom sac have distinct peptide profiles, with milked venom predominantly composed of venom sac peptides. We isolated and characterized novel α-helical, amphipathic venom sac peptides that constitute a new family of venom toxins termed ampulexins. Injection of the most abundant venom peptide, ampulexin 1, into the subesophageal ganglion of cockroaches resulted in a short-term increase in escape threshold. Neither milked venom nor venom peptides interfered with g...

  • Life History of the Emerald Jewel Wasp Ampulex compressa
    Journal of Hymenoptera Research, 2018
    Co-Authors: Ryan Arvidson, Victor Landa, Stephen Frankenberg, Michael E Adams
    Abstract:

    The Emerald Jewel Wasp Ampulexcompressa (Fabricius) is an endoparasitoid of the American cockroach Periplanetaamericana (Linnaeus). Its host subjugation strategy is unusual in that envenomation is directed into the host central nervous system, eliciting a long-term behavior modification termed Hypokinesia, turning stung cockroaches into a lethargic and compliant, but not paralyzed, living food supply for wasp offspring. A.compressa manipulates hypokinesic cockroaches into a burrow, where it oviposits a single egg onto a mesothoracic leg, hatching three days later. Herein we describe the life history and developmental timing of A.compressa . Using head capsule measurements and observations of mandibular morphology, we found that the larvae develop through three instars, the first two ectoparasitoid, and the third exclusively endoparasitoid. The first two instars have mandibles sufficient for piercing and cutting the cuticle respectively, while the third instar has a larger and blunter mandibular structure. During ecdysis to the third instar, the larva enters the body cavity of the cockroach, consuming internal tissues selectively, including fat body and skeletal muscle, but sparing the gut and Malpighian tubules. The developmental timing to pupation is similar between males and females, but cocoon volume and mass, and pupation duration are sexually dimorphic. Further, we show that the difference in cocoon mass and volume can be used to predict sex before eclosion, which is valuable for studies in venom pharmacology, as only females produce venom.

  • Ampulexins: A New Family of Peptides in Venom of the Emerald Jewel Wasp, Ampulex compressa
    2018
    Co-Authors: Eugene L. Moore, Ryan Arvidson, Jean Paul Urenda, Haroun Mohammed, Elizabeth Duong, Christopher Banks, Michael E Adams
    Abstract:

    The parasitoid wasp Ampulex compressa injects venom directly into the brain and subesophageal ganglion of the cockroach Periplaneta americana, inducing a 7 to 10 day lethargy termed Hypokinesia. Hypokinesia presents as a significant reduction in both escape response and spontaneous walking. We examined aminergic and peptidergic components of milked venom with HPLC and MALDI-TOF mass spectrometry. HPLC coupled with electrochemical detection confirmed the presence of dopamine in milked venom, while mass spectrometry revealed that the venom gland and venom sac have distinct peptide profiles, with milked venom predominantly composed of venom sac peptides. We isolated and characterized novel α-helical, amphipathic venom sac peptides that constitute a new family of venom toxins termed ampulexins. Injection of the most abundant venom peptide, ampulexin 1, into the subesophageal ganglion of cockroaches resulted in a short-term increase in escape threshold. Neither milked venom nor venom peptides interfered with growth of Escherichia coli or Bacillus thuringiensis on agar plates, and exposure to ampulexins or milked venom did not induce cell death in Chinese hamster ovary cells (CHO-K1) or Hi5 cells (Trichoplusia ni)

Michael E Adams - One of the best experts on this subject based on the ideXlab platform.

  • ampulexins a new family of peptides in venom of the emerald jewel wasp ampulex compressa
    Biochemistry, 2018
    Co-Authors: Eugene L Moore, Ryan Arvidson, Jean Paul Urenda, Haroun Mohammed, Christopher N Banks, Elizabeth Duong, Michael E Adams
    Abstract:

    The parasitoid wasp Ampulex compressa injects venom directly into the brain and subesophageal ganglion of the cockroach Periplaneta americana, inducing a 7 to 10 day lethargy termed Hypokinesia. Hypokinesia presents as a significant reduction in both escape response and spontaneous walking. We examined aminergic and peptidergic components of milked venom with HPLC and MALDI-TOF mass spectrometry. HPLC coupled with electrochemical detection confirmed the presence of dopamine in milked venom, while mass spectrometry revealed that the venom gland and venom sac have distinct peptide profiles, with milked venom predominantly composed of venom sac peptides. We isolated and characterized novel α-helical, amphipathic venom sac peptides that constitute a new family of venom toxins termed ampulexins. Injection of the most abundant venom peptide, ampulexin 1, into the subesophageal ganglion of cockroaches resulted in a short-term increase in escape threshold. Neither milked venom nor venom peptides interfered with g...

  • Life History of the Emerald Jewel Wasp Ampulex compressa
    Journal of Hymenoptera Research, 2018
    Co-Authors: Ryan Arvidson, Victor Landa, Stephen Frankenberg, Michael E Adams
    Abstract:

    The Emerald Jewel Wasp Ampulexcompressa (Fabricius) is an endoparasitoid of the American cockroach Periplanetaamericana (Linnaeus). Its host subjugation strategy is unusual in that envenomation is directed into the host central nervous system, eliciting a long-term behavior modification termed Hypokinesia, turning stung cockroaches into a lethargic and compliant, but not paralyzed, living food supply for wasp offspring. A.compressa manipulates hypokinesic cockroaches into a burrow, where it oviposits a single egg onto a mesothoracic leg, hatching three days later. Herein we describe the life history and developmental timing of A.compressa . Using head capsule measurements and observations of mandibular morphology, we found that the larvae develop through three instars, the first two ectoparasitoid, and the third exclusively endoparasitoid. The first two instars have mandibles sufficient for piercing and cutting the cuticle respectively, while the third instar has a larger and blunter mandibular structure. During ecdysis to the third instar, the larva enters the body cavity of the cockroach, consuming internal tissues selectively, including fat body and skeletal muscle, but sparing the gut and Malpighian tubules. The developmental timing to pupation is similar between males and females, but cocoon volume and mass, and pupation duration are sexually dimorphic. Further, we show that the difference in cocoon mass and volume can be used to predict sex before eclosion, which is valuable for studies in venom pharmacology, as only females produce venom.

  • Ampulexins: A New Family of Peptides in Venom of the Emerald Jewel Wasp, Ampulex compressa
    2018
    Co-Authors: Eugene L. Moore, Ryan Arvidson, Jean Paul Urenda, Haroun Mohammed, Elizabeth Duong, Christopher Banks, Michael E Adams
    Abstract:

    The parasitoid wasp Ampulex compressa injects venom directly into the brain and subesophageal ganglion of the cockroach Periplaneta americana, inducing a 7 to 10 day lethargy termed Hypokinesia. Hypokinesia presents as a significant reduction in both escape response and spontaneous walking. We examined aminergic and peptidergic components of milked venom with HPLC and MALDI-TOF mass spectrometry. HPLC coupled with electrochemical detection confirmed the presence of dopamine in milked venom, while mass spectrometry revealed that the venom gland and venom sac have distinct peptide profiles, with milked venom predominantly composed of venom sac peptides. We isolated and characterized novel α-helical, amphipathic venom sac peptides that constitute a new family of venom toxins termed ampulexins. Injection of the most abundant venom peptide, ampulexin 1, into the subesophageal ganglion of cockroaches resulted in a short-term increase in escape threshold. Neither milked venom nor venom peptides interfered with growth of Escherichia coli or Bacillus thuringiensis on agar plates, and exposure to ampulexins or milked venom did not induce cell death in Chinese hamster ovary cells (CHO-K1) or Hi5 cells (Trichoplusia ni)