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Experimental studies on ozonation of ethylenethiourea

Xinyu Dong,Junwang Meng,Bo Yang,Yang Zhang,Jie Gan,Xi Shu,Jinian Shu,

环境科学学报(英文版) , 2011,
Abstract: The experimental study on ozonation of ethylenethiourea (ETU) is conducted. The reaction of gas-phase ETU with 0.63×10-6 mol/L ozone is carried out in a 200-L reaction chamber. The secondary organic aerosol (SOA) resulted from the ozonation of gas-phase ETU is observed with a scanning mobility particle size (SMPS). The rapid exponential growth of SOA reveals that the atmospheric lifetime of ETU vapor towards ozone reaction is less than four days. The ozonation of dry ETU particles, ETU-contained water droplets and ETU aqueous solution is investigated with a vacuum ultraviolet photoionization aerosol time-of-flight mass spectrometer (VUV-ATOFMS). The formation of 2-imidazoline is observed in the ozonation of dry ETU particles and ETU-contained water droplets. The formation of 2-imidazoline and ethylenerea is observed in the ozonation of ETU aqueous solution.
Egr3 Dependent Sympathetic Target Tissue Innervation in the Absence of Neuron Death  [PDF]
Lin Li,Laurie C. Eldredge,David H. Quach,Avinash Honasoge,Katherine Gruner,Warren G. Tourtellotte
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0025696
Abstract: Nerve Growth Factor (NGF) is a target tissue derived neurotrophin required for normal sympathetic neuron survival and target tissue innervation. NGF signaling regulates gene expression in sympathetic neurons, which in turn mediates critical aspects of neuron survival, axon extension and terminal axon branching during sympathetic nervous system (SNS) development. Egr3 is a transcription factor regulated by NGF signaling in sympathetic neurons that is essential for normal SNS development. Germline Egr3-deficient mice have physiologic dysautonomia characterized by apoptotic sympathetic neuron death and abnormal innervation to many target tissues. The extent to which sympathetic innervation abnormalities in the absence of Egr3 is caused by altered innervation or by neuron death during development is unknown. Using Bax-deficient mice to abrogate apoptotic sympathetic neuron death in vivo, we show that Egr3 has an essential role in target tissue innervation in the absence of neuron death. Sympathetic target tissue innervation is abnormal in many target tissues in the absence of neuron death, and like NGF, Egr3 also appears to effect target tissue innervation heterogeneously. In some tissues, such as heart, spleen, bowel, kidney, pineal gland and the eye, Egr3 is essential for normal innervation, whereas in other tissues such as lung, stomach, pancreas and liver, Egr3 appears to have little role in innervation. Moreover, in salivary glands and heart, two tissues where Egr3 has an essential role in sympathetic innervation, NGF and NT-3 are expressed normally in the absence of Egr3 indicating that abnormal target tissue innervation is not due to deregulation of these neurotrophins in target tissues. Taken together, these results clearly demonstrate a role for Egr3 in mediating sympathetic target tissue innervation that is independent of neuron survival or neurotrophin deregulation.
Development of Postural Muscles and Their Innervation  [PDF]
J. IJkema-Paassen,A. Gramsbergen
Neural Plasticity , 2005, DOI: 10.1155/np.2005.141
Abstract: Control of posture is a prerequisite for efficient motor performance. Posture depends on muscles capable of enduring contractions, whereas movements often require quick, forceful muscle actions. To serve these different goals, muscles contain fibers that meet these different tasks. Muscles with strong postural functions mainly consist of slow muscle fibers with a great resistance against fatigue. Flexor muscles in the leg and arm muscles are mainly composed of fast muscle fibers producing relatively large forces that are rapidly fatigable. Development of the neuromuscular system continues after birth. We discuss in the human baby and in animal experiments changes in muscle fiber properties, regression from polyneural into mononeural innervation, and developmental changes in the motoneurons of postural muscles during that period. The regression of poly-neural innervation in postural muscles and the development of dendrite bundles of their motoneurons seem to be linked to the transition from the immature into the adult-like patterns of moving and postural control.
A Case of Fetus in Fetu  [cached]
Ghulam Mustafa,Bilal Mirza,Shahid Iqbal,Afzal Sheikh
APSP Journal of Case Reports , 2012,
Abstract: Fetus in fetu is a rare developmental aberration, characterized by encasement of partially developed monozygotic, diamniotic, and monochorionic fetus into the normally developing host. A 4-month-old boy presented with abdominal mass. Radiological investigations gave the suspicion of fetus in fetu. At surgery a fetus enclosed in an amnion like membrane at upper retroperitoneal location was found and excised. The patient is doing well after the operation.
Alves,Nilton; Candido,Paulo Laino; Fraz?o,Renata;
International Journal of Morphology , 2004, DOI: 10.4067/S0717-95022004000300011
Abstract: the pronator quadratus is the principal muscle responsible for pronation of forearm, helped by the pronator teres. to study the innervation of the pronator teres, eighteen forearms from a formol fixed corpses were dissected and the relationship of the median nerve to the pronator teres was examined. the elbow articular line was used as reference point. in all cases the most branches of the median nerve to the pronator teres began in the arm distal third part, whereas the most branches penetrated at the distal half of the forearm proximal third part (75% in right upper limb and 75.8% in left upper limb). the treatment of pronator syndrome could be making easier with the knowledge of the anatomical distribution of nerves
The Professional Medical Journal , 2006,
Abstract: Objective: To evaluate the role of Colour Doppler Ultrasound in the management of small forgestational age fetus. SGA or IUGR. Design: Descriptive study. Place & duration of study: Study performed in theDeptt. of Radiology & Deptt. of Gynae. & Obstetrics in Allied Hospital, Faisalabad from August 2005 to July 2006.Material & Methods: This study was carried out on 45 patients admitted through antenatal clinic having suspicion ofcarrying small for gestational age fetus. A brief clinical record including age, parity, nutritional status, intercurrent illness,per-vaginum bleeding, history of drug intake, smoking, past obstetrical history was recorded. Methods involved inscreening SGA fetuses were measurement of Symphyseal Fundal Height chart & Ultrasound biometry, Biophysicalprofile (BPP), Cardiotocography (CTG), Middle cerebral and Umbilical Arteries Doppler studies were performed afteradmission in the management of SGA fetuses. All these information were recorded in a specially designed Performa.Results: Out of 45 SGA fetuses 15(33.3%) were constitutionally small, 20(44.4%) had history of pre-eclampsia,2(4.4%) had cardiac disease, 3(6.6%) had placental abnormalities, 5(11.1%) had multiple gestations. Gestation ofpatients ranged between 30-36 weeks. Umbilical Artery Doppler was used as the primary surveillance tool. Smallfetuses with normal Doppler and anomaly scan were managed on out-patient basis with fortnightly Doppler ultrasound.15 patients (33.3%) with normal end-diastolic flow were delivered at 37 weeks. 20 patients (44.47%) with absent orreversed end-diastolic flow were delivered at 34-35 weeks. 10 patients (22.2%) at 30 weeks gestation with abnormalDoppler study were managed on CTG (Cardiotocography) & biophysical profile over a period ranging between 1-14days. Perinatal mortality was 8.8% (4 cases) mostly due to extreme prematurity. Conclusion: Doppler ultrasound isa very helpful tool in the management of small for gestational age fetuses & it reduces perinatal morbidity & Mortality.
Alves,Nilton; Laino Candido,Paulo; Fraz?o,Renata;
International Journal of Morphology , 2004, DOI: 10.4067/S0717-95022004000400002
Abstract: the pronator quadratus is the main muscle responsible for pronation of forearm, helped by the pronator teres. to study the innervation of the pronator quadratus, eighteen forearms from a formol fixed corpses were dissected. we examined the relationship between the anterior interosseous nerve and the pronator quadratus. the wrist articular line was used as reference point. the branch which had the most proximal penetration into the pronator quadratus was 5.4 cm above the wrist articular line in a right forearm and 5.6 cm in a left one, and the branch which had the most distal penetration was 2.5 cm above the wrist articular line in a right forearm and 2.4 cm in a left one. the length of the anterior interosseous nerve and the width of the pronator quadratus muscle were measured. a great knowledge of the anatomical distribution of nerves could be of great help in treatment of the anterior interosseous syndrome
Metabolic scaling law for fetus and placenta  [PDF]
Carolyn M. Salafia,Michael Yampolsky
Quantitative Biology , 2008,
Abstract: We present a version of Kleiber's scaling law for fetus and placenta.
Development of Cortical GABAergic Innervation  [PDF]
Alex M. Thomson
Frontiers in Cellular Neuroscience , 2011, DOI: 10.3389/fncel.2011.00014
Abstract: The mature neocortex contains many different classes of GABAergic inhibitory interneurons, distributed, with some degree of selectivity, through six layers, and through many different regions. Some of the events in the early lives of these neurones that may determine their ultimate destination, their maturation and their selective innervation of targets appropriate for each subtype, are discussed. Both time and place of birth influence the class of interneuron that an early post-mitotic interneuronal precursor will become, driven by the selective expression of different combinations of transcription factors in different regions of their birth places in the ganglionic eminence and ventricular zone. The long distance migration of these precursors along tangential routes in marginal, subventricular, and intermediate zones and their final radial movement, into the developing cortex, is regulated by chemical cues, both attractant and repellent. Once they arrive at their final destination, they must integrate into the developing circuitry. As they mature within the cortex, their axons grow and branch in highly specific patterns that may be partially determined by the genetic blueprint for each interneuronal class and partly by the environment in which they find themselves. Finally, as each interneuron class begins to form synapses with only certain postsynaptic targets, cell–cell recognition, most probably via protein–protein interactions across the synaptic cleft, facilitate the formation of appropriate synapses.
Acardiac fetus: a challenge to pathologists, obstetricians and neonatologists Acardiac fetus: a challenge to pathologists, obstetricians and neonatologists  [cached]
Cristiane Rúbia Ferreira,Angélica Braz Sim?es,Maria Cláudia Nogueira Zerbini,Virgínia Spínola Quintal
Autopsy and Case Reports , 2012,
Abstract: nulo Acardius is one of the most severe human malformations, a rare complication present only in monozygotic and monochorionic multiple pregnancies. In this disorder, the major defect is the lack of well-defined cardiac structure in acardiac fetus, whose irrigation is maintained through placental vascular anastomoses with the normal fetus, called fetal donor, thereby establishing a reverse arterial perfusion in the umbilical cord of the acardiac twin (TRAP sequence). The poor circulation leads to a state of hypoxia in the early stages of fetal development, causing structural abnormalities, with different phenotypes, which are classified as: Acardius acephalus, anceps, and acormus amorphus. We relate a case of an acardiac anceps fetus that interestingly was reported by the physicians to present spasmodic movements just after the delivery. Due to severe malformations observed in an acardiac twin by the time of delivery, it is likely that many cases go unnoticed or misdiagnosed. The pathological findings are briefly reviewed to provide an adequate post mortem diagnosis of acardiac fetus and placental examination.
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