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Lichen Planopilaris Responsive to a Novel Phytoactive Botanical Treatment: A Case Series. Dermatol Ther (Heidelb) 2022; 12:1697-1710. [PMID: 35674981 PMCID: PMC9276860 DOI: 10.1007/s13555-022-00749-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/17/2022] [Indexed: 11/28/2022] Open
Abstract
INTRODUCTION Lichen planopilaris (LPP) is characterized by chronic scarring alopecia that is progressive and typically refractory to therapy. Current drug treatments are suboptimal and not applicable for long-term use because of the high potential for adverse effects, warranting safer and more effective treatment alternatives. METHODS Based on our previous success in treating a patient with central centrifugal cicatricial alopecia using a topical botanical formulation (Gashee), we reviewed records of four patients with biopsy-proven LPP treated with the topical formulation alone or in combination with its oral preparation. Three patients had failed previous treatment with intralesional steroid injections, topical minoxidil, tacrolimus, and clobetasol. Physical examination and photographic documentation were also used as outcome measures. Treatment duration with the botanical formulations ranged from 6 weeks to 9.5 months. RESULTS All patients showed overall improvement in surrogate indicators of LPP activity as evidenced by the disappearance of symptoms (pruritus, tenderness, scalp irritation, and hair shedding), improvement in hair growth, and reduction in redness. All reported a high satisfaction level and no adverse effects. CONCLUSIONS Patients with treatment-refractory LPP responded to a novel botanical treatment. To the best of our knowledge, this is the first published report of LPP responding to a plant-based natural treatment. Further evaluation of this treatment in a controlled trial with a larger number of patients is warranted.
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Treatment-Refractory Central Centrifugal Cicatricial Alopecia Responsive to a Novel Botanical Treatment. Clin Cosmet Investig Dermatol 2022; 15:609-619. [PMID: 35422647 PMCID: PMC9004676 DOI: 10.2147/ccid.s358618] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 03/31/2022] [Indexed: 01/06/2023]
Abstract
Purpose Central centrifugal cicatricial alopecia (CCCA) is the most common cause of scarring alopecia in women of African descent. However, current treatments for CCCA, such as immunosuppressants and immunomodulatory pharmaceutical agents, have suboptimal efficacy and undesirable side effects. This case series reports the therapeutic effect of a new botanical formulation (Dr. UGro Gashee) in four patients with histologically supported diagnoses of CCCA. The formulations contain at least three phytoactive ingredients that affect multiple targets in the cascade of pathophysiologic events contributing to CCCA. Possible mechanisms of action include anti-inflammatory effects, inhibiting proinflammatory cytokines, and the net antifibrotic effect of inhibiting transforming growth factor-beta while upregulating AMP-activated protein kinase and peroxisome proliferator-associated receptor-gamma activity. Patients and Methods Four African American women with treatment-refractory CCCA were treated with a new topical botanical formula (cosmeceutical) alone or in combination with its oral formulation (nutraceutical) for 8 weeks to 1 year. The cosmeceutical and nutraceutical treatments contain similar phytoactive ingredient profiles. Treatment outcomes were collected using documented patient reports and images and by direct observation. Results In all patients, scalp pruritus cessation occurred within 2 weeks of treatment, and significant hair regrowth was observed within 2 months. All patients reported a high satisfaction level without adverse effects. Conclusion Patients with treatment-refractory CCCA responded to the novel botanical treatment reported in this study. Further evaluations in a controlled trial with more patients are warranted.
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Early Postmarket Results with EmboTrap II Stent Retriever for Mechanical Thrombectomy: A Multicenter Experience. AJNR Am J Neuroradiol 2021; 42:904-909. [PMID: 33707283 DOI: 10.3174/ajnr.a7067] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 11/23/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE EmboTrap II is a novel stent retriever with a dual-layer design and distal mesh designed for acute ischemic stroke emergent large-vessel occlusions. We present the first postmarket prospective multicenter experience with the EmboTrap II stent retriever. MATERIALS AND METHODS A prospective registry of patients treated with EmboTrap II at 7 centers following FDA approval was maintained with baseline patient characteristics, treatment details, and clinical/radiographic follow-up. RESULTS Seventy patients were treated with EmboTrap II (mean age, 69.9 years; 48.6% women). Intravenous thrombolysis was given in 34.3%, and emergent large-vessel occlusions were located in the ICA (n = 18), M1 (n = 38), M2 or M3 (n = 13), and basilar artery (n = 1). The 5 × 33 mm device was used in 88% of cases. TICI ≥ 2b recanalization was achieved in 95.7% (82.3% in EmboTrap II-only cases), and first-pass efficacy was achieved in 35.7%. The NIHSS score improved from a preoperative average of 16.3 to 12.1 postprocedure and to 10.5 at discharge. An average of 2.5 [SD, 1.8] passes was recorded per treatment, including non-EmboTrap attempts. Definitive treatment was performed with an alternative device (aspiration or stent retriever) in 9 cases (12.9%). Some hemorrhagic conversion was noted in 22.9% of cases, of which 4.3% were symptomatic. There were no device-related complications. CONCLUSIONS Initial postmarket results with the EmboTrap II stent retriever are favorable and comparable with those of other commercially available stent retrievers. Compared with EmboTrap II, the first-generation EmboTrap may have a higher first-pass efficacy; however, data are limited by retrospective case analysis, incomplete clinical follow-up, and small sample size, necessitating future trials.
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Applications of a Novel Microangioscope for Neuroendovascular Intervention. AJNR Am J Neuroradiol 2020; 42:347-353. [PMID: 33361372 DOI: 10.3174/ajnr.a6900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/05/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Visualization in neuroendovascular intervention currently relies on biplanar fluoroscopy and contrast administration. With the advent of endoscopy, direct visualization of the intracranial intravascular space has become possible with microangioscopes. We analyzed the efficacy of our novel microangioscope to enable direct observation and inspection of the cerebrovasculature, complementary to a standard fluoroscopic technique. MATERIALS AND METHODS Iterations of microangioscopes were systematically evaluated for use in neurodiagnostics and neurointerventions in both live animal and human cadaveric models. Imaging quality, trackability, and navigability were assessed. Diagnostic procedures assessed included clot identification and differentiation, plaque identification, inspection for vessel wall injury, and assessment of stent apposition. Interventions performed included angioscope-assisted stent-retriever thrombectomy, clot aspiration, and coil embolization. RESULTS The microangioscope was found helpful in both diagnosis and interventions by independent evaluators. Mean ratings of the imaging quality on a 5-point scale ranged from 3.0 (clot identification) to 4.7 (Pipeline follow-up). Mean ratings for clinical utility ranged from 3.0 (aspiration thrombectomy) to 4.7 (aneurysm treatment by coil embolization and WEB device). CONCLUSIONS This fiber optic microangioscope can safely navigate and visualize the intravascular space in human cadaveric and in vivo animal models with satisfactory resolution. It has potential value in diagnostic and neurointerventional applications.
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Multicenter Postmarket Analysis of the Neuroform Atlas Stent for Stent-Assisted Coil Embolization of Intracranial Aneurysms. AJNR Am J Neuroradiol 2020; 41:1037-1042. [PMID: 32467183 DOI: 10.3174/ajnr.a6581] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 03/29/2020] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The Neuroform Atlas is a new microstent to assist coil embolization of intracranial aneurysms that recently gained FDA approval. We present a postmarket multicenter analysis of the Neuroform Atlas stent. MATERIALS AND METHODS On the basis of retrospective chart review from 11 academic centers, we analyzed patients treated with the Neuroform Atlas after FDA exemption from January 2018 to June 2019. Clinical and radiologic parameters included patient demographics, aneurysm characteristics, stent parameters, complications, and outcomes at discharge and last follow-up. RESULTS Overall, 128 aneurysms in 128 patients (median age, 62 years) were treated with 138 stents. Risk factors included smoking (59.4%), multiple aneurysms (27.3%), and family history of aneurysms (16.4%). Most patients were treated electively (93.7%), and 8 (6.3%) underwent treatment within 2 weeks of subarachnoid hemorrhage. Previous aneurysm treatment failure was present in 21% of cases. Wide-neck aneurysms (80.5%), small aneurysm size (<7 mm, 76.6%), and bifurcation aneurysm location (basilar apex, 28.9%; anterior communicating artery, 27.3%; and middle cerebral artery bifurcation, 12.5%) were common. A single stent was used in 92.2% of cases, and a single catheter for both stent placement and coiling was used in 59.4% of cases. Technical complications during stent deployment occurred in 4.7% of cases; symptomatic thromboembolic stroke, in 2.3%; and symptomatic hemorrhage, in 0.8%. Favorable Raymond grades (Raymond-Roy occlusion classification) I and II were achieved in 82.9% at discharge and 89.5% at last follow-up. mRS ≤2 was determined in 96.9% of patients at last follow-up. The immediate Raymond-Roy occlusion classification grade correlated with aneurysm location (P < .0001) and rupture status during treatment (P = .03). CONCLUSIONS This multicenter analysis provides a real-world safety and efficacy profile for the treatment of intracranial aneurysms with the Neuroform Atlas stent.
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Surpass Flow Diverter for Treatment of Posterior Circulation Aneurysms. AJNR Am J Neuroradiol 2016; 38:582-589. [PMID: 28007769 DOI: 10.3174/ajnr.a5029] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/11/2016] [Indexed: 12/30/2022]
Abstract
BACKGROUND AND PURPOSE Flow diverters for the treatment of posterior circulation aneurysms remain controversial. We aimed to identify factors contributing to outcome measures in patients treated with the Surpass flow diverter for aneurysms in this location. MATERIALS AND METHODS We conducted an observational study of 53 patients who underwent flow-diverter treatment for posterior circulation aneurysms at 15 centers. Key outcome measures were mortality, complete aneurysm occlusion, and modified Rankin Scale score at follow-up. RESULTS At follow-up (median, 11.3 months; interquartile range, 5.9-12.7 months), 9 patients had died, resulting in an all-cause mortality rate of 17.3% (95% CI, 7%-27.6%); 7 deaths (14%) were directly related to the procedure and none occurred in patients with a baseline mRS score of zero. After adjusting for covariates, a baseline mRS of 3-5 was more significantly (P = .003) associated with a higher hazard ratio for death than a baseline mRS of 0-2 (hazard ratio, 17.11; 95% CI, 2.69-109.02). After adjusting for follow-up duration, a 1-point increase in the baseline mRS was significantly (P < .001) associated with higher values of mRS at follow-up (odds ratio, 2.93; 95% CI, 1.79-4.79). Follow-up angiography in 44 patients (median, 11.3 months; interquartile range, 5.9-12.7 months) showed complete aneurysm occlusion in 29 (66%; 95% CI, 50.1%-79.5%). CONCLUSIONS Clinical results of flow-diverter treatment of posterior circulation aneurysms depend very much on patient selection. In this study, poorer outcomes were related to the treatment of aneurysms in patients with higher baseline mRS scores. Angiographic results showed a high occlusion rate for this subset of complex aneurysms.
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Characteristics of neonatal transports in California. J Perinatol 2016; 36:1122-1127. [PMID: 27684413 DOI: 10.1038/jp.2016.102] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 04/15/2016] [Accepted: 04/28/2016] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To describe the current scope of neonatal inter-facility transports. STUDY DESIGN California databases were used to characterize infants transported in the first week after birth from 2009 to 2012. RESULTS Transport of the 22 550 neonates was classified as emergent 9383 (41.6%), urgent 8844 (39.2%), scheduled 2082 (9.2%) and other 85 (0.4%). In addition, 2152 (9.5%) were initiated for delivery attendance. Most transports originated from hospitals without a neonatal intensive care unit (68%), with the majority transferred to regional centers (66%). Compared with those born and cared for at the birth hospital, the odds of being transported were higher if the patient's mother was Hispanic, <20 years old, or had a previous C-section. An Apgar score <3 at 10 min of age, cardiac compressions in the delivery room, or major birth defect were also risk factors for neonatal transport. CONCLUSION As many neonates receive transport within the first week after birth, there may be opportunities for quality improvement activities in this area.
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E-091 Treatment of Aneurysms of the Pericallosal Artery with the Pipeline Embolization Device. J Neurointerv Surg 2016. [DOI: 10.1136/neurintsurg-2016-012589.163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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E-022 The Surpass™ IntraCranial Aneurysm Embolization System Pivotal Trial to treat large OR giant wide neck aneurysms (SCENT Trial). J Neurointerv Surg 2016. [DOI: 10.1136/neurintsurg-2016-012589.94] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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E-070 Endovascular Techniques for Achievement of Better Flow Diverter Wall Apposition. J Neurointerv Surg 2016. [DOI: 10.1136/neurintsurg-2016-012589.142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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E-131 endovascular reconstruction of intradural vertebral artery fusiform dissecting aneurysms with the pipeline embolization device. J Neurointerv Surg 2015. [DOI: 10.1136/neurintsurg-2015-011917.205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Regional variation in antenatal corticosteroid use: a network-level quality improvement study. Pediatrics 2015; 135:e397-404. [PMID: 25601974 PMCID: PMC4306799 DOI: 10.1542/peds.2014-2177] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/20/2014] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Examination of regional care patterns in antenatal corticosteroid use (ACU) rates may be salient for the development of targeted interventions. Our objective was to assess network-level variation using California perinatal care regions as a proxy. We hypothesized that (1) significant variation in ACU exists within and between California perinatal care regions, and (2) lower performing regions exhibit greater NICU-level variability in ACU than higher performing regions. METHODS We undertook cross-sectional analysis of 33,610 very low birth weight infants cared for at 120 hospitals in 11 California perinatal care regions from 2005 to 2011. We computed risk-adjusted median ACU rates and interquartile ranges (IQR) for each perinatal care region. The degree of variation was assessed using hierarchical multivariate regression analysis with NICU as a random effect and region as a fixed effect. RESULTS From 2005 to 2011, mean ACU rates across California increased from 82% to 87.9%. Regional median (IQR) ACU rates ranged from 68.4% (24.3) to 92.9% (4.8). We found significant variation in ACU rates among regions (P < .0001). Compared with Level IV NICUs, care in a lower level of care was a strongly significant predictor of lower odds of receiving antenatal corticosteroids in a multilevel model (Level III, 0.65 [0.45-0.95]; Level II, 0.39 [0.24-0.64]; P < .001). Regions with lower performance in ACU exhibited greater variability in performance. CONCLUSIONS We found significant variation in ACU rates among California perinatal regions. Regional quality improvement approaches may offer a new avenue to spread best practice.
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E-079 Retrospective multicentre analysis of treatment strategies and outcomes with Solitaire FF for acute ischaemic stroke after FDA approval. J Neurointerv Surg 2013. [DOI: 10.1136/neurintsurg-2013-010870.137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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E-074 Intravenous thrombolysis and endovascular therapy for acute ischemic stroke with internal carotid artery occlusion: a systematic review of clinical outcomes. J Neurointerv Surg 2012. [DOI: 10.1136/neurintsurg-2012-010455c.74] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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E-022 Tandem symptomatic internal carotid artery and persistent hypoglossal artery stenosis treated by endovascular stenting and flow reversal: case report: Abstract E-022 Figure 1. J Neurointerv Surg 2012. [DOI: 10.1136/neurintsurg-2012-010455c.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Radiographic features of tumefactive giant cavernous angiomas. Acta Neurochir (Wien) 2008; 150:49-55; discussion 55. [PMID: 18066488 DOI: 10.1007/s00701-007-1455-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Accepted: 10/22/2007] [Indexed: 12/25/2022]
Abstract
BACKGROUND Giant cavernous angiomas (GCAs) are very rare, and imaging features of GCAs can be very different from those of typical cavernous angiomas (CAs), making them a diagnostic challenge. The purpose of the study was to evaluate the radiographic features of GCAs, with an emphasis on the differentiating features from neoplastic lesions. METHODS The neuroradiological findings of 18 patients who harbored a histologically verified GCA (CA of 4 cm or larger) were reviewed retrospectively. The magnetic resonance imaging (MRI) appearance, enhancement pattern, presence of edema or mass effect, size, and location of each lesion were recorded. When available, pertinent clinical information, including age, sex, and mode of presentation, was obtained. FINDINGS Seizures, neurologic deficits, hemorrhage, and hydrocephalus were the most common presenting symptoms. The lesions were hyperdense and nonenhancing on computed tomography with frequent calcifications. On MRI, the lesions most commonly had a multicystic appearance, representing blood of various ages, and multiple complete hemosiderin rings. GCAs can present in any location with associating edema and mass effect, giving them a tumefactive appearance. No developmental venous anomaly was observed with any lesion. CONCLUSIONS Most GCAs in our series presented as multicystic lesions with complete hemosiderin rings on MRI, giving a "bubbles of blood" appearance. Although this characteristic feature is helpful in the diagnosis of many cases of GCAs, the correct diagnosis in the remaining cases may not be apparent until histopathological evaluation of the specimen is made.
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Incidental giant arachnoid granulation. AJNR Am J Neuroradiol 2006; 27:1491-2. [PMID: 16908565 PMCID: PMC7977517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Arachnoid granulations may expand the dural sinuses or inner table of the skull. Although usually incidental, giant arachnoid granulations that are of sufficient size to fill the lumen of a dural sinus and cause local dilation or filling defects can rarely cause symptoms due to sinus obstruction leading to venous hypertension. This 31-year-old man presented with a 3-month history of progressive bifrontal headaches and a giant arachnoid granulation at the posterior superior sagittal sinus. Intrasinus pressure measurements showed no significant pressure difference across the lesion to explain the headaches, which were then treated medically. Dural sinus pressure measurement, in certain cases of giant arachnoid granulations, can be used to exclude the lesion as the cause of the patient's symptoms.
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Poster Abstracts. J Liposome Res 2003. [DOI: 10.1081/lpr-120017490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Distinct sites of origin of oligodendrocytes and somatic motoneurons in the chick spinal cord: oligodendrocytes arise from Nkx2.2-expressing progenitors by a Shh-dependent mechanism. Development 2001; 128:1369-79. [PMID: 11262237 DOI: 10.1242/dev.128.8.1369] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In the vertebrate spinal cord, oligodendrocytes arise from the ventral part of the neuroepithelium, a region also known to generate somatic motoneurons. The emergence of oligodendrocytes, like that of motoneurons, depends on an inductive signal mediated by Sonic hedgehog. We have defined the precise timing of oligodendrocyte progenitor specification in the cervico-brachial spinal cord of the chick embryo. We show that ventral neuroepithelial explants, isolated at various development stages, are unable to generate oligodendrocytes in culture until E5 but become able to do so in an autonomous way from E5.5. This indicates that the induction of oligodendrocyte precursors is a late event that occurs between E5 and E5.5, precisely at the time when the ventral neuroepithelium stops producing somatic motoneurons. Analysis of the spatial restriction of oligodendrocyte progenitors, evidenced by their expression of O4 or PDGFR(α), indicate that they always lie within the most ventral Nkx2.2-expressing domain of the neuroepithelium, and not in the adjacent domain characterized by Pax6 expression from which somatic motoneurons emerge. We then confirm that Shh is necessary between E5 and E5.5 to specify oligodendrocyte precursors but is no longer required beyond this stage to maintain ongoing oligodendrocyte production. Furthermore, Shh is sufficient to induce oligodendrocyte formation from ventral neuroepithelial explants dissected at E5. Newly induced oligodendrocytes expressed Nkx2.2 but not Pax6, correlating with the in vivo observation. Altogether, our results show that, in the chick spinal cord, oligodendrocytes originate from Nkx2.2-expressing progenitors.
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Pleurodeles waltl, amphibian, Urodele, is a suitable biological model for embryological and physiological space experiments on a vertebrate. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 2001; 28:569-578. [PMID: 11799990 DOI: 10.1016/s0273-1177(01)00384-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Pleurodeles waltl (amphibian, Urodele) is an appropriate biological model for space experiments on a vertebrate. One reason for interest in this animal concerns the study of the effects of absence of gravity on embryonic development. First, after mating (on Earth) the females retain live, functional sperm in their cloacum for up to 5 months, allowing normal in vivo fertilisation after hormonal stimulation. Second, their development is slow, which allows analyses of all the key stages of ontogenesis from the oocyte to swimming tailbud embryos or larvae. We have performed detailed studies and analyses of the effects of weightlessness on amphibian Pleurodeles embryos, fertilised and allowed to develop until the swimming larvae stage. These experiments were performed in space during three missions on the MIR-station: FERTILE I, FERTILE II and NEUROGENESIS respectively in 1996, 1998 and 1999. We show that in microgravity abnormalities appeared at specific stages of development compared to 1g-centrifuge control embryos and 1g-ground control embryos. In this report we describe abnormalities occurring in the central nervous system. These modifications occur during the neurulation process (delay in the closure of the neural tube and failure of closure of this tube in the cephalic area) and at the early tailbud stage (microcephaly observed in 40% of the microgravity-embryos). However, if acephalic and microcephalic embryos are not taken into account, these abnormalities did not disturb further morphological, biochemical and functional development and the embryos were able to regulate and a majority of normal hatching and swimming larvae were obtained in weightlessness with a developmental time-course equivalent to that of 1g-centrifuge control embryos (on the MIR station) and 1g-ground control embryos.
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Structure determination of porcine haemoglobin. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2000; 56:304-12. [PMID: 10713517 DOI: 10.1107/s0907444900000093] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
To investigate a potential candidate material for making artificial red blood cells to supplement blood transfusion, the X-ray structure of porcine haemoglobin at 1.8 A resolution was determined as part of research towards synthesizing human blood. Porcine haemoglobin was crystallized by the vapor-diffusion method, producing crystals of dimensions 0.3-0.5 mm after successive seeding. The crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 68.10, b = 72.27, c = 114.85 A. The initial phase was determined by the molecular-replacement method, using human oxyhaemoglobin as a model. The final R factor was 21.1% for 36 820 reflections after validation of 574 water molecules. The r.m.s. deviations of bond lengths, angles, torsion angles and improper angles from their ideal values are 0.017 A, 3.0, 20.6 and 1.8 degrees, respectively. The average B factor is 33.63 A(2) for the haemoglobin molecule and 50.53 A(2) for the water molecules. The structure could be superimposed on a 2.8 A resolution structure with an r.m.s. difference of 0.59 A in main-chain atomic positions and 1. 27 A in side-chain atomic positions. Porcine and human haemoglobins are compared. A tentative model for artificial blood is proposed based on the complementarity relationship of the surface charges between haemoglobin and the surrounding cell membrane.
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Abstract
Paclitaxel is an anticancer agent with low aqueous solubility. More extensive clinical use of this drug is somewhat delayed due to lack of appropriate delivery vehicles. An attempt was made to adopt an o/w emulsion as the drug carrier which incorporated paclitaxel in the triacylglycerol stabilized by a mixed-emulsifier system. A suitable formulation was found in this study: 0.75 mg/ml paclitaxel, 10% (w/v) oil blend, 4% (w/v) EPC, 3% (w/v) Tween 80 in 2.25% (w/v) glycerol solution. The formulated emulsion has very good stability when stored at 4 degrees C, and the paclitaxel containment efficiency can be maintained above 95% and the mean emulsion diameter around 150 nm for at least 3 months. Paclitaxel-emulsion displayed cytotoxicity against HeLa cells with IC50 at 30 nM. The average life span of ascitic-tumor-bearing mice was prolonged significantly by the treatment of paclitaxel-emulsion (P<0.05). The formulated emulsion is a promising carrier for paclitaxel and other lipophilic drugs.
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Effects of shear stress on metabolic function of the co-culture system of hepatocyte/nonparenchymal cells for a bioartificial liver. ASAIO J 1998; 44:M441-4. [PMID: 9804468 DOI: 10.1097/00002480-199809000-00023] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
To improve the culture conditions of hepatocytes for use as a bioartificial liver, the effects of shear flow on the co-culture system of hepatocytes/nonparenchymal cells (NPC) were investigated. A flow chamber with a collagen coated rectangular glass plate, where hepatocytes (5 x 10(4) cell/cm2) and NPC (2 x 10(5) cell/cm2) were seeded, was used to attain a shear stress of 4.7 dyne/cm2. Concentrations of ammonia and urea in the medium were measured daily during the 2 week experiment. The metabolic activity of hepatocytes in the homotypic culture were lower than those of the co-culture, especially when the cultivation time exceeded 1 week. In addition, the applied shear flow promoted activity of the co-culture system. An enhancement in the rates of ammonium removal and urea synthesis was obtained in the perfusion systems. Morphologic observation revealed that aggregates of hepatocytes formed abundantly in the perfusion system and hepatocytes developed a cuboid shape. This suggested that perfusion affected the function and morphology of hepatocytes in the co-culture system. Shear flow could induce cell-cell interactions and secretion of extracellular matrix through the activation of NPC.
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High-efficiency prism light guides with confocal parabolic cross sections. APPLIED OPTICS 1998; 37:5227-5233. [PMID: 18286001 DOI: 10.1364/ao.37.005227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Prism light guides are often used for transporting and distributing light. Typically such guides are tubular structures lined with a flexible prismatic sheet material that confines light by means of total internal reflection. Inasmuch as the prismatic material is produced as a flat sheet, such guides require at least one seam in formation of the tubular structure, and the optical imperfection associated with seams is often a dominant loss mechanism. We present a new configuration for the cross-sectional shape of a prism light guide that substantially reduces the loss caused by such seams.
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Differentiation in microgravity of neural and muscle cells of a vertebrate (amphibian). ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 1998; 22:303-308. [PMID: 11541410 DOI: 10.1016/s0273-1177(98)80024-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The CELIMENE space experiment (CELulles en Impesanteur: Muscle Et Neurone Embryonnaires) was devoted to the study of the influence of gravity on the differentiation, the organisation and the maintenance of the highly specialised nervous system and muscular system. CELIMENE was carried out during the first flight of the IBIS hardware (Instrument for BIology in Space) with the fully automatic space mission PHOTON 10 in February 1995. Using the amphibian Pleurodeles waltl as a vertebrate model, in vitro experiments involved immunocytochemical detection of glial-, neuronal- and muscle-specific markers, and neurotransmitters in cells developed under conditions of microgravity compared with 1g controls, on-board and on the ground. We observed that the altered gravity did not disturb cell morphogenesis or differentiation.
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Induction of oligodendrocyte progenitors in the trunk neural tube by ventralizing signals: effects of notochord and floor plate grafts, and of sonic hedgehog. Mech Dev 1996; 60:13-32. [PMID: 9025058 DOI: 10.1016/s0925-4773(96)00595-3] [Citation(s) in RCA: 123] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Recent evidence indicates that oligodendrocytes originate initially from the ventral neural tube. We have documented in chick embryos the effect of early ventralization of the dorsal neural tube on oligodendrocyte differentiation. Notochord or floor plate grafted at stage 10 in dorsal position induced the development of oligodendrocyte precursors in the dorsal spinal cord. In vitro, oligodendrocytes differentiated from medial but not intermediate neural plate explants, suggesting that the ventral restriction of oligodendrogenesis is established early. Furthermore, quail fibroblasts overexpressing the ventralizing signal Sonic Hedgehog induced oligodendrocyte differentiation in both the intermediate neural plate and the E4 dorsal spinal cord. These results strongly suggest that the emergence of the oligodendrocyte lineage is related to the establishment of the dorso-ventral polarity of the neural tube.
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Simulation of oxygen saturation of hemoglobin solution, RBC suspension and hemosome by a neural network system. ARTIFICIAL CELLS, BLOOD SUBSTITUTES, AND IMMOBILIZATION BIOTECHNOLOGY 1996; 24:143-51. [PMID: 8907692 DOI: 10.3109/10731199609118880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Hemoglobin-based artificial blood substitutes as oxygen carrier is advantageous over current plasma expander. In this study, oxygen saturation of hemoglobin solution, red blood cell suspension and artificial blood substitute under various conditions were measured by yeast-consuming-oxygen experiments instead of spectrophotometer. The empirical results were assigned into training feedforward back-propagation neural network system in order to simulate the oxygen saturation model modulated by those factors such as pH, [Cl-], [2,3-DPG], pO2 and pCO2. Consequently, this neural network is able to simulate accurately the oxygen saturation of Hb solution. The prediction of hemosome is not agreed well possible because of the resistance of transport of oxygen. However, the results showed neural net can offer a simple and convenient way in comparison with the conventional methods, especially in dealing with complex and ambiguous problem.
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Prevalence of hypothalamic-pituitary imaging abnormalities in impotent men with secondary hypogonadism. J Urol 1996; 155:529-33. [PMID: 8558653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
PURPOSE Because prevalence of structural lesions of the pituitary and hypothalamus in impotent men with secondary hypogonadism was undefined, we evaluated 164 men 27 to 79 years old whose chief complaint was erectile dysfunction and who repeatedly had low serum testosterone levels (less than 230 ng./dl.). MATERIALS AND METHODS With computerized tomography or magnetic resonance imaging of the sella we detected potentially serious lesions (pituitary lesions greater than 5 mm. or any hypothalamic lesion) in 11 men (6.7%, 95% confidence interval 2.9 to 10.5%), including 5 pituitary microadenomas (5 mm. or larger), 4 pituitary macroadenomas and 2 hypothalamic lesions. RESULTS Mean serum testosterone was lower in patients with (121 +/- 66 ng./dl., standard deviation) than without (177 +/- 39 ng./dl.) hypothalamic or pituitary imaging abnormalities (p < 0.001). For every 10 ng./dl. decrease in testosterone the risk of hypothalamic or pituitary imaging abnormalities increased 1.2-fold (p < 0.005). Macroadenomas and hypothalamic lesions were confined to 6 subjects with testosterone levels of 104 ng./dl. or less. CONCLUSIONS The risk of hypothalamic or pituitary imaging abnormalities is low among men evaluated for erectile dysfunction and secondary hypogonadism. However, this risk increases markedly when the serum testosterone level is markedly decreased.
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The pleurodele, an animal model for space biology studies. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 1996; 17:265-268. [PMID: 11538625 DOI: 10.1016/0273-1177(95)00643-s] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Pleurodeles waltl, an Urodele amphibian is proposed as a model for space biology studies. Our laboratory is developing three types of experiments in space using this animal: 1) in vivo fertilization and development ("FERTILE" project); 2) influence of microgravity and space radiation on the organization and preservation of specialized structures in the neurons and muscle cells (in vitro; "CELIMENE" PROJECT); 3) influence of microgravity on tissue regeneration (muscle, bone, epidermis and spinal cord).
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[Fibroblast growth factors (FGF-2) and delayed involution of the posterior limbs of the slow-worm embryo (Anguis fragilis, L.)]. COMPTES RENDUS DE L'ACADEMIE DES SCIENCES. SERIE III, SCIENCES DE LA VIE 1995; 318:573-8. [PMID: 7671004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Administration at doses of 1,800 ng to 6,200 ng of basic fibroblast growth factor (bFGF), around the posterior limb buds of young slow-worm (Anguis fragilis, L.) embryos developing in cultured eggs has, after 4 to 6 days, in several embryos (10 among 15, treated at stage of allantoic bud, from 3 to 9 mm long), delayed the involution of these posterior limbs: their anlagen are larger than the control ones and histological examination shows an increase, between 20% and 30%, of cell density in the mesodermal component of the limb bud. These results bring into light the possibility to control, to some degree, the regressive evolution of the limbs.
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[Fibroblast growth factor (FGF-2) and delayed involution of the posterior limbs of the slow-worm embryo (Anguis fragilis, L.)]. COMPTES RENDUS DE L'ACADEMIE DES SCIENCES. SERIE III, SCIENCES DE LA VIE 1995; 318:51-6. [PMID: 7757804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Administration at doses of 1,800 ng to 6,200 ng of basic fibroblast growth factor (bFGF), around the posterior limb buds of young slow-worm (Anguis fragilis, L.) embryos developing in cultured eggs has, after 4 to 6 days, in several embryos (10 among 15, treated at stage of allantoic bud, from 3 to 9 mm long), delayed the involution of these posterior limbs: their anlagen are larger than the control ones and histological examination shows an increase, between 20% and 30%, of cell density in the mesodermal component of the limb bud. These results bring into light the possibility to control, to some degree, the regressive evolution of the limbs.
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Application of aqueous two-phase systems in separation/purification of stroma free hemoglobin from animal blood. ARTIFICIAL CELLS, BLOOD SUBSTITUTES, AND IMMOBILIZATION BIOTECHNOLOGY 1994; 22:641-9. [PMID: 7994385 DOI: 10.3109/10731199409117894] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Aqueous two-phase system (ATPS) is suitable for treatment of biological materials. It has been traditionally employed in the separation of product from fermentation broth, and in the extraction of large-molecule proteins from colloid solution. The separation method based on ATPS features simple, rapid and continuous operation with low equipment cost. A PEG/Salt aqueous two-phase system is studied, and developed for hemoglobin (Hb) separation from animal bloods. Stroma free hemoglobin (SFHb) was extracted from 200ml packed red blood cells by the two-stage aqueous two-phase system and subsequently was desalted and dialyzed by ultrafiltration. It took only 2.5hr to complete overall process to purify SFHb. The purity of SFHb was analyzed by HPLC and IEF (silver staining). Large partition coefficients of Hb have been observed with proper selection of PEG molecular weight, added concentrations of PEG and salt in each phase. The SFHb of very high purity which is free of other proteins (< 0.1% impurity) and phospholipids (< 2% impurities) may be obtained from human packed RBCs. A two-stage extraction design using ATPS separation concept is very simple and useful for purification of SFHb. The method may be further developed to offer potent technology for hemoglobin separation from animal blood and future production industry of blood substitutes.
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DNA synthesis decline involved in the developmental arrest of the limb buds in the embryos of the slow worm, Anguis fragilis (L.). THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 1992; 36:303-10. [PMID: 1525018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The present study was carried out to try and detect the biochemical mechanism involved in the developmental arrest of the limb bud in a serpentiform Reptile. Autoradiograpy, following tritiated thymidine incorporation, in embryos of the slow-worm (Anguis fragilis, L.) reveals a strong decrease in the rate of DNA synthesis in the mesodermal cells of the limb bud, after the degeneration of the apical ectodermal ridge (AER); the curve (a function of Gompertz) visualizing this decline shows that the drop in DNA synthesis becomes accentuated just after the degeneration of the AER. This decrease precedes the reduction of the mitotic index, the cell degeneration in the mesoderm and the other regressive changes occurring in the limb bud; it thus appears as the main causative factor of the developmental arrest of the limb bud. Furthermore, these results suggest that one of the functions of the AER would be to maintain a high level of DNA synthesis in the mesoderm underlying the AER in a normal limb bud.
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The purification and comparative analysis of hemoglobin from animal bloods. BIOMATERIALS, ARTIFICIAL CELLS, AND IMMOBILIZATION BIOTECHNOLOGY : OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY FOR ARTIFICIAL CELLS AND IMMOBILIZATION BIOTECHNOLOGY 1992; 20:477-88. [PMID: 1391467 DOI: 10.3109/10731199209119672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Various methods for the separation and purification of Hb from animal blood have been investigated to establish the optimal and highly reliable purification process. The Hb obtained from various sources, i.e., bovine, pig and human bloods were analyzed and compared using simple and fast analytical methods, including, electrophoresis, isoelectric focusing, and spectroscopy to study the characterization of protein structure. Further investigation along this line will enable us to realize the ultimate objectives of development for artificial RBC substitutes.
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Extracellular matrix: an immunological and biochemical (CAT and TOH activity) survey of in vitro differentiation of isolated amphibian neuroblasts. CELL DIFFERENTIATION AND DEVELOPMENT : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF DEVELOPMENTAL BIOLOGISTS 1990; 30:219-33. [PMID: 1976426 DOI: 10.1016/0922-3371(90)90141-i] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
After neural induction certain cells in the neuroepithelium immediately acquire the property to express certain neural phenotypes (Duprat et al., 1984, 1987). However, the activity of almost all the specific enzymes involved in the biosynthesis of neurotransmitters is considerably higher when neurectodermal cells are cultured with chordamesodermal cells than when they are cultured alone. The stimulating effects of chordamesoderm do not appear to be due to diffusible factors (Duprat et al., 1985b). The present study was designed to investigate the role of extracellular matrix components in neuronal cell differentiation. We showed that the extracellular matrix cannot replace chordamesoderm in stimulating the biochemical differentiation of neuroblasts, although fibronectin and especially laminin stimulate morphological differentiation. We suggest that interaction between neuronal and non-neuronal cells plays an important part in functional biochemical differentiation, whereas the molecules of extracellular matrix are important for morphological differentiation.
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From presumptive ectoderm to neural cells in an amphibian. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 1990; 34:149-56. [PMID: 2203454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
As an immediate consequence of neural induction during gastrulation, some neuroectodermal cells acquire the ability to develop a number of specific neuronal and astroglial features, without requiring subsequent chordamesodermal cues. Thus, cholinergic, dopaminergic, noradrenergic, gabaergic, somatostatinergic, enkephalinergic, etc. traits are expressed in cultures of neural plate and neural fold isolated from amphibian late gastrulae immediately after induction and cultured in a defined medium. These results strongly suggest that at the late gastrula stage, the neural precursor population does not yet constitute a homogeneous set of cells. It was of interest to know the origin of this heterogeneity. Is it a direct result of the process of neural induction itself, stochastic phenomena being involved or not at the cellular level, or does it reflect a pre-existing heterogeneity in the presumptive ectoderm? At the early gastrula state, presumptive ectoderm can be neuralized consecutively to its dissociation into single cells. Using this experimental model, we have demonstrated by means of immunological probes that neuralized presumptive ectodermal cells, without any intervention of the chordamesoderm (natural inducing tissue), can develop autonomously into glial and neuronal lineages. These data suggest the existence of diverse predispositions of presumptive ectodermal cells. Competent ectoderm seems to be a heterogeneous structure with cells presenting distinct neural predispositions that can emerge as a consequence of a permissive inductive signal without real specificity (such as a target tissue dissociation). Moreover, such a differentiated neuronal population includes neurons of the GABAergic and enkephalinergic phenotypes but not of the cholinergic, catecholaminergic, somatostatinergic, etc. phenotypes. These data show that the developmental program of ectodermal cells induced without interaction with the chordamesoderm appears restricted compared to the naturally induced ectoderm. Experiments are now under way to analyze such sequential neural events.
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Initial GABAergic expression in embryonic amphibian neuroblasts after neural induction. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 1989; 33:445-53. [PMID: 2701425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
At the late gastrula-early neurula stage some embryonic neuroblasts from neural plate and neural fold present apparently as a consequence of neural induction, the capability to develop in vitro into different neuronal subpopulations (cholinergic, dopaminergic, noradrenergic, somatostatinergic and some other peptidergic subpopulations without ongoing influences from the chordamesoderm (Duprat et al., 1987). Using the same in vitro model system, the aim of the present work was to delineate the abilities of these neuroblasts to develop GABAergic traits. The initial appearance and development of GABAergic phenotype has been quantitated by assaying the activity of glutamic acid decarboxylase (GAD). GAD activity was undetectable at the early gastrula stage (stage 8a) and was slightly measurable at the early neurula stage (stage 14- onset of the culture). It increased subsequently over the next 14 days in vitro. The temporal pattern of appearance and development of GAD activity in culture was in agreement with that observed in vivo. Immunocytochemical studies showed that GABA-like immunoreactivity was expressed in vitro in a subpopulation of neurons. Thus the developmental program for GAD expression and GABA phenotype maturation is acquired at least in some neuronal precursors. These data together with previously reported results on the expression of cholinergic, catecholaminergic and peptidergic phenotypes demonstrate that different neuronal subpopulations emerge near the end of gastrulation i.e. immediately after neural induction. The embryonic origin of this neuroblast heterogeneity remains to be determined.
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Neural induction: embryonic determination elicits full expression of specific neuronal traits. Development 1985. [DOI: 10.1242/dev.89.supplement.167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In Pleurodeles waltl, the early neuronal differentiation of precursor cells from late gastrula stage has been studied by culture in vitro from either isolated neural plate (NP) or isolated neural fold (NF).
The aim of this study was to delineate the information acquired by ectodermal target cells during neural induction. By culturing these cells in vitro either with or without the underlying chordamesoderm, we showed that in the absence of chordamesodermal influence such NP or NF cells exhibited a high degree of biochemical and morphological differentiation as revealed by the synthesis and the storage of neurotransmitters, the activity of specific enzymes, as well as by the expression of neuronal markers: specific changes in cell surface carbohydrates, tetanus toxin binding sites and neurofilament polypeptides. Remarkable changes in the cell adhesive properties were the first events observed in the different central (NP) and peripheral (NF) types.
In cocultures the chordamesodermal cells exert a beneficial influence on this differentiation, specially increasing acetylcholine synthesis. There are some differences between central (NP) or peripheral (NF) neuroblast response to this further notochord or mesodermal influence.
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Neural induction: embryonic determination elicits full expression of specific neuronal traits. JOURNAL OF EMBRYOLOGY AND EXPERIMENTAL MORPHOLOGY 1985; 89 Suppl:167-83. [PMID: 3831212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
In Pleurodeles waltl, the early neuronal differentiation of precursor cells from late gastrula stage has been studied by culture in vitro from either isolated neural plate (NP) or isolated neural fold (NF). The aim of this study was to delineate the information acquired by ectodermal target cells during neural induction. By culturing these cells in vitro either with or without the underlying chordamesoderm, we showed that in the absence of chordamesodermal influence such NP or NF cells exhibited a high degree of biochemical and morphological differentiation as revealed by the synthesis and the storage of neurotransmitters, the activity of specific enzymes, as well as by the expression of neuronal markers: specific changes in cell surface carbohydrates, tetanus toxin binding sites and neurofilament polypeptides. Remarkable changes in the cell adhesive properties were the first events observed in the different central (NP) and peripheral (NF) types. In cocultures the chordamesodermal cells exert a beneficial influence on this differentiation, specially increasing acetylcholine synthesis. There are some differences between central (NP) or peripheral (NF) neuroblast response to this further notochord or mesodermal influence.
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Abstract
Adrenal rest tumors of the testes may occur in conditions associated with increased circulating adrenocorticotropic hormone (ACTH), including congenital adrenal hyperplasia (CAH) and Addison disease. Sonographically, these tumors appear as multiple round, hypoechoic nodules near the testicular hilus and are usually bilateral. They may undergo extensive fibrosis and become hyperechoic with acoustic shadowing. In the absence of excess ACTH or characteristic ultrasound findings, biopsy is recommended to exclude malignancy. Because malignant degeneration is very rare, close clinical and sonographic follow-up without biopsy is generally sufficient. Serial sonograms are useful to document stability or regression of tumor size during glucocorticoid replacement therapy.
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In vitro differentiation of neuronal precursor cells from amphibian late gastrulae; morphological, immunocytochemical studies, biosynthesis, accumulation and uptake of neurotransmitters. JOURNAL OF EMBRYOLOGY AND EXPERIMENTAL MORPHOLOGY 1985; 86:71-87. [PMID: 2863321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Neuronal differentiation has been studied in dissociated cell cultures from early neurulae of Pleurodeles waltl and Ambystoma mexicanum. Cocultures were prepared from the neural primordium and underlying chordamesoderm. NP and NF cultures were prepared from isolated neural plate and neural folds, respectively. Neuronal precursors in NP and NF cultures had distinctive aggregation properties already evident after 1-2 days in culture. After 10-15 days, mature neurones and synapses were observed by electron microscopy in the three culture types. The expression of neurofilament polypeptides and tetanus-toxin-binding sites was also present in these cultures. A small percentage of neurones contained cytochemically detectable catecholamine. Many neurones took up tritiated dopamine with a high affinity. Quantitative measurement of [3H]acetylcholine synthesis and storage from [3H]choline were negative at the early neurula stage and in 5 to 15-day-old NF cultures, and remained low in 5 to 15-day-old NP cultures. Acetylcholine production in cocultures increased linearly with time and was always much higher than in NP cultures. These results suggest that, at the early neurula stage, some neuronal precursors have acquired the capacity to express a high degree of morphological and biochemical differentiation even in the absence of further chordamesoderm influence. However, the chordamesodermal cells in the cultures increased acetylcholine synthesis.
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Stimulating effect of the divalent cation ionophore A 23187 on in vitro neuroblast differentiation; comparative studies with myoblasts. EXPERIENTIA 1981; 37:154-8. [PMID: 6786913 DOI: 10.1007/bf01963205] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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Abstract
The case of a 72-year-old female with a retroperitoneal abscess which contained cholesterol gallstones is presented. The pathogenesis of this unusual complication of gallbladder disease is discussed.
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Comparative study of the activity of boric, benzene-boronic and methyl-benzene-boronic acids upon respiration, general metabolism and systemic hemodynamics of the anesthetized dog. ARZNEIMITTEL-FORSCHUNG 1975; 25:1023-8. [PMID: 1174408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The authors compared the action of boric, benzene-boronic and p-methyl-benzene-boronic acids on respiration and general metabolism and on systemic hemodynamics of the anesthetized dog. They further investigated the effects on the arterial blood pressure in the rat and on the isolated rabbit heart. In the dogs, the three acids were shown to have no significant action on the systolic, diastolic and mean arterial blood pressures and a slight stimulating action on the differential arterial blood pressure. On the contrary, in the rat, all the acids were hypotensive. This action was dose dependent. In the entire animal, as well as in the isolated rabbit heart, benzene-boronic and p-methyl-benzene-boronic acids depressed the myocardial contractility. Whereas boric acid did not act on the heart contractility in situ in anesthetized dogs, it slightly stimulated the myocardial contractility of the isolated rabbit heart. The two acids seemed to be directly active on the myocardial cell. In the anesthetized dog, cardiac performances were first depressed then stimulated. Both benzene-boronic and p-methyl-benzene-boronic acids were ventilatory depressors: they reduced ventilatory output and rhythm, they first decreased then increased total O2 consumption and CO2 production.
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Effects of zinc-nitrosylpentacyanoferrate on the cardiovascular system. ARZNEIMITTEL-FORSCHUNG 1974; 24:308-12. [PMID: 4407422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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46
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[Study of formamide and methylformamide effect on ventilation and systemic hemodynamics in the dog]. AGRESSOLOGIE: REVUE INTERNATIONALE DE PHYSIO-BIOLOGIE ET DE PHARMACOLOGIE APPLIQUEES AUX EFFETS DE L'AGRESSION 1973; 14:251-8. [PMID: 4794731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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47
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[Study of the toxic aggressiveness of zinc on respiration, geneal metabolism and systemic hemodyamics in chloralose treated dogs]. Therapie 1971; 26:1049-58. [PMID: 5160345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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[Comparative study of the action of hydroxy 2 methoxy 3 benzaldoxime and of the corresponding aldehyde on the smooth muscle]. Therapie 1970; 25:649-54. [PMID: 4394068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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[Studies on antibilharzial drugs. Synthesis of substituted-(4-amino-1-naphthylazo)benzenes and substituted-[4-(diethylaminoethylamino)-1-naphthylazo]benzenes]. YAO XUE XUE BAO = ACTA PHARMACEUTICA SINICA 1966; 13:30-37. [PMID: 5952717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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