Specific blockade of muscle acetylcholine receptor by α-conotoxin MIA and MIB / 药学学报

The α-conotoxins are peptide toxins that are identified from the venom of marine cone snails and they hold outstanding potency on various subtypes of nicotinic acetylcholine receptors (nAChRs). nAChRs have an important role in regulating transmitter release, cell excitability, and neuronal integration, so nAChR dysfunctions have been involved in a variety of severe pathologies. Four types of α-3/5 conotoxins MI, MIA, MIB and MIC have been found from Conus magus. Among them, the activity and selectivity of MIA and MIB have not been well studied. In this study, four α-3/5 conotoxins MI, MIA, MIB and MIC were synthesized by solid peptide synthesis method, and the bioactivities of them were screened by double electrode voltage clamp electrophysiology. The results showed that MIA and MIB selectively inhibited muscle type acetylcholine receptors with IC50 values of 14.45 and 72.78 nmol·L-1, respectively, which are slightly weaker than MI and MIC. Molecular docking results have shown MIA and MIB interact with muscle-type nAChRs with similar mechanism. The reasons for activity differences may relate to the size of the N-terminal amino acids. Together, the conotoxins MIA and MIB may have the potential to develop as a tool for detect the function of muscle type nAChRs, as well as the diagnosis or treat of related diseases.

Isolation and characterization of five novel disulfide-poor conopeptides from Conus marmoreus venom

Background: Conopeptides from cone snail venom have aroused great interest related to the discovery of novel bioactive candidates, due to their excellent prospects for the treatment of various health problems such as pain, addiction, psychosis and epilepsy. In order to explore novel biopeptides, we investigated the structure and function of five novel conopeptides isolated from the venom of Conus marmoreus from South China Sea. Methods: C. marmoreus crude venom was prepared, fractionated and purified by HPLC system. The primary sequences of the five novel disulfide-poor conopeptides Mr-1 to Mr-5 were identified by comprehensive analysis of de novo MALDI-TOF tandem mass spectrometry and Edman degradation data. In order to investigate their function, these five conopeptides were synthesized by Fmoc-SPPS chemistry, and their biological effects at several heterologous rat nicotinic acetylcholine receptor (nAChR) subtypes (α1β1δε, α3β2, α3β4, α4β2) were determined by electrophysiological technique. Results: Five novel disulfide-poor conopeptides were identified and named as follows: Mr-1 (DWEYHAHPKPNSFWT), Mr-2 (YPTRAYPSNKFG), Mr-3 (NVIQAPAQSVAPP NTST), Mr-4 [KENVLNKLKSK(L/I)] and Mr-5 [NAVAAAN(L/I)PG(L/I)V]. None of them contains a disulfide bond. The sequences of conopeptides Mr-2 to Mr-5 do not belong to any category of the known disulfide-poor conopeptides. No significant activity against the above nAChR subtypes were observed for the five conopeptides at 100 µM. Conclusion: We purified and structurally characterized five novel disulfide-poor conopeptides from C. marmoreus crude venom and first investigated their nAChR inhibitory effects. This work expanded our knowledge on the structure and function of disulfide-poor conopeptides from this cone snail venom.(AU)

Counting of fetal caudal vertebral body ossification center below terminal conus medullaris in the screening of the closed spine bifida and tethered cord syndrome / 中华超声影像学杂志

Objective:To assess the significance of counting the number of caudal vertebral ossification centers (OCN) below fetal terminal conus medullaris in the screening for closed spina bifida and tethered cord syndrome (TCS).Methods:The OCN was counted in 961 normal fetuses(normal group) between 17 and 41 gestational weeks and in 140 fetuses with closed spina bifida or tethered cord syndrome(abnormal group) from Jan.2013 to Dec.2020 in Affiliated Shenzhen Maternity & Child Healthcare Hospital, Southern Medical University, Women and Children′s Hospital, School of Medicine, Xiamen University and Maternity and Child Health Care of Guangxi Zhuang Autonomous Region. The OCN was counted in the dorsal mid-sagittal section of fetal caudal spine.The reliability and agreement test were evaluated by intraclass correlation coefficients in another 50 normal fetuses. The OCN was compared between two groups. ROC curve and the cut-off value were constructed and calculated.Results:In normal group, the N increased with the growing of gestational age.In the subgroup of 17-20 weeks, the OCN ranged from 5 to 7 in most fetuses. In the others subgroups, the OCN was equal to or greater than 6 in 99.9% cases and more than 6 in 97.1% cases. In abnormal group, OCN was less than 7 in 93.0% fetuses and less than 6 in 82.8% cases. There were statistical differences between the two groups except for the subgroup of 17-20 gestational weeks( P<0.05). With the cut-off value of 6.5, the specificity and sensitivity were 93.0% and 94.3% respectively for predicting the presence of closed spinal dysraphism or TCS. Conclusions:OCN is a simple way to evaluate the position of conus medullaris and to screen for the skin-covered spine dysraphism or TSC. OCN is more than 6 in most normal fetuses. Further evaluation of spine is required in fetuses with N less than or equal to 6.

Proteomic analysis of Red Sea Conus taeniatus venom reveals potential biological applications

Diverse and unique bioactive neurotoxins known as conopeptides or conotoxins are produced by venomous marine cone snails. Currently, these small and stable molecules are of great importance as research tools and platforms for discovering new drugs and therapeutics. Therefore, the characterization of Conus venom is of great significance, especially for poorly studied species. Methods: In this study, we used bioanalytical techniques to determine the venom profile and emphasize the functional composition of conopeptides in Conus taeniatus, a neglected worm-hunting cone snail. Results: The proteomic analysis revealed that 84.0% of the venom proteins were between 500 and 4,000 Da, and 16.0% were > 4,000 Da. In C. taeniatus venom, 234 peptide fragments were identified and classified as conotoxin precursors or non-conotoxin proteins. In this process, 153 conotoxin precursors were identified and matched to 23 conotoxin precursors and hormone superfamilies. Notably, the four conotoxin superfamilies T (22.87%), O1 (17.65%), M (13.1%) and O2 (9.8%) were the most abundant peptides in C. taeniatus venom, accounting for 63.40% of the total conotoxin diversity. On the other hand, 48 non-conotoxin proteins were identified in the venom of C. taeniatus. Moreover, several possibly biologically active peptide matches were identified, and putative applications of the peptides were assigned. Conclusion: Our study showed that the composition of the C. taeniatus-derived proteome is comparable to that of other Conus species and contains an effective mix of toxins, ionic channel inhibitors and antimicrobials. Additionally, it provides a guidepost for identifying novel conopeptides from the venom of C. taeniatus and discovering conopeptides of potential pharmaceutical importance.(AU)

Proteomic analysis of Red Sea Conus taeniatus venom reveals potential biological applications

Abstract Background: Diverse and unique bioactive neurotoxins known as conopeptides or conotoxins are produced by venomous marine cone snails. Currently, these small and stable molecules are of great importance as research tools and platforms for discovering new drugs and therapeutics. Therefore, the characterization of Conus venom is of great significance, especially for poorly studied species. Methods: In this study, we used bioanalytical techniques to determine the venom profile and emphasize the functional composition of conopeptides in Conus taeniatus, a neglected worm-hunting cone snail. Results: The proteomic analysis revealed that 84.0% of the venom proteins were between 500 and 4,000 Da, and 16.0% were > 4,000 Da. In C. taeniatus venom, 234 peptide fragments were identified and classified as conotoxin precursors or non-conotoxin proteins. In this process, 153 conotoxin precursors were identified and matched to 23 conotoxin precursors and hormone superfamilies. Notably, the four conotoxin superfamilies T (22.87%), O1 (17.65%), M (13.1%) and O2 (9.8%) were the most abundant peptides in C. taeniatus venom, accounting for 63.40% of the total conotoxin diversity. On the other hand, 48 non-conotoxin proteins were identified in the venom of C. taeniatus. Moreover, several possibly biologically active peptide matches were identified, and putative applications of the peptides were assigned. Conclusion: Our study showed that the composition of the C. taeniatus-derived proteome is comparable to that of other Conus species and contains an effective mix of toxins, ionic channel inhibitors and antimicrobials. Additionally, it provides a guidepost for identifying novel conopeptides from the venom of C. taeniatus and discovering conopeptides of potential pharmaceutical importance.

Clinical analysis of 56 cases with surgical operation of congenital tumor in conus medullaris position / 中国医师杂志

Objective@#To analyze the curative effect of 56 cases with surgical operation of congenital tumor in conus medullaris position, to provide valuable reference information for the surgical operation of congenital tumor in conus medullaris position.@*Methods@#The cases were from 56 patients with congenital tumors in conus medullaris position in Xinjiang Uygur municipal people's hospital from January 2015 to February 2018. According to the classifications of congenital tumors in the conus medullaris position, surgical operation was performed on patients. The curative effect of patients with all kinds of congenital tumors in the conus medullaris position was analyzed and summarized.@*Results@#After 9 months of the follow-up: ⑴ There were totally 18 cases of epidermoid cysts, 16 cases with obvious improvement in lower limb numbness and lower limb motor function, 13 cases with the pain degree effectively relieved and 3 cases without significant improvement in early defecation function. ⑵ There were 15 cases of teratomas, 13 cases without significant improvement in lower extremity numbness, 2 cases with reduced lower extremity numbness, 3 cases with reduced urination and defecation function disturbance and 1 case not recovered. There was no recurrence of tumor. ⑶ There were 8 lipoma patients who were cured and discharged without urination and defecation function disturbance. Life was basically self-sustaining. ⑷ There were 9 cases of hemangioblastoma with significant improvement in spinal cord function, 5 cases without postoperative pain symptoms and 1 case with significant improvement in pain degree. ⑸ There were 6 cases of ependymoma, 2 cases with significant reduction on limb numbness symptoms, 1 case with urinary retention after surgery. There was no significant change in muscle strength of the 2 cases before and after surgery.@*Conclusions@#The clinical effect of surgical operation of congenital tumor in conus medullaris position is clear. Combined with imaging examination and attention to surgical precautions, the surgical treatment effect of congenital tumors in the conus region of the spinal cord can be effectively improved.

Isolation and structural identification of a new T1-conotoxin with unique disulfide connectivities derived from Conus bandanus

Conopeptides are neuropharmacological peptides derived from the venomous salivary glands of cone snails. Among 29 superfamilies based on conserved signal sequences, T-superfamily conotoxins, which belong to the smallest group, include four different frameworks that contain four cysteines denominated I, V, X and XVI. In this work, the primary structure and the cysteine connectivity of novel conotoxin of Conus bandanus were determined by tandem mass spectrometry using collision-induced dissociation. Methods: The venom glands of C. bandanus snails were dissected, pooled, and extracted with 0.1% trifluoroacetic acid in three steps and lyophilized. The venom was fractionated and purified in an HPLC system with an analytical reversed-phase C18 column. The primary peptide structure was analyzed by MALDI TOF MS/MS using collision-induced dissociation and confirmed by Edman's degradation. The peptide's cysteine connectivity was determined by rapid partial reduction-alkylation technique. Results: The novel conotoxin, NGC1C2(I/L)VREC3C4, was firstly derived from de novo sequencing by MS/MS. The presence of isoleucine residues in this conotoxin was confirmed by the Edman degradation method. The conotoxin, denominated Bn5a, belongs to the T1-subfamily of conotoxins. However, the disulfide bonds (C1-C4/C2-C3) of Bn5a were not the same as found in other T1-subfamily conopeptides but shared common connectivities with T2-subfamily conotoxins. The T1-conotoxin of C. bandanus proved the complexity of the disulfide bond pattern of conopeptides. The homological analysis revealed that the novel conotoxin could serve as a valuable probe compound for the human-nervous-system norepinephrine transporter. Conclusion: We identified the first T1-conotoxin, denominated Bn5a, isolated from C. bandanus venom. However, Bn5a conotoxin exhibited unique C1-C4/C2-C3 disulfide connectivity, unlike other T1-conotoxins (C1-C3/C2-C4). The structural and homological analyses herein have evidenced novel conotoxin Bn5a that may require further investigation.(AU)

Isolation and characterization of five novel mini-M conotoxins from the venom of mollusk-hunter snail Conus bandanus

Objective: To determine the new M-superfamily conotoxins from molluscivorous snail Conus bandanus in Vietnam. Methods: Conus bandanus venom was fractionated and purified on HPLC system with an analytical reversed-phase C18 column in order to screen small conotoxins. The primary structure of peptide was analyzed by matrix-assisted laser desorption/ionization time of flight tandem mass spectrometry using collision-induced dissociation and confirmed by Edman's degradation method. Results: Five new conotoxins were biochemically characterized from the crude venom of the mollusk-hunting cone snail Conus bandanus, which were collected at Ke Ga reef of the Nha Trang Bay (Vietnam). Each conotoxin had 15 or 16 amino acid residues and shared the same characteristic cysteine framework V as -CC-C-C-CC-. They were termed as Bn3b, Bn3c, Bn3d, Bn3e and Bn3f following the conotoxins nomenclature. Conclusions: The conotoxins Bn3b, Bn3e, and Bn3f are categorized in the mini-M conotoxins of the M1 branch, while conotoxins Bn3c and Bn3d are categorized in the mini-M conotoxins of the M2 branch. The homological analysis reveals that these conotoxins could serve as promising probe compounds for voltage-gated sodium channels.

Clinical analysis of 56 cases with surgical operation of congenital tumor in conus medullaris position / 中国医师杂志

Objective To analyze the curative effect of 56 cases with surgical operation of congenital tumor in conus medullaris position,to provide valuable reference information for the surgical operation of congenital tumor in conus medullaris position.Methods The cases were from 56 patients with congenital tumors in conus medullaris position in Xinjiang Uygur municipal people's hospital from January 2015 to February 2018.According to the classifications of congenital tumors in the conus medullaris position,surgical operation was performed on patients.The curative effect of patients with all kinds of congenital tumors in the conus medullaris position was analyzed and summarized.Results After 9 months of the follow-up:(1) There were totally 18 cases of epidermoid cysts,16 cases with obvious improvement in lower limb numbness and lower limb motor function,13 cases with the pain degree effectively relieved and 3 cases without significant improvement in early defecation function.(2) There were 15 cases of teratomas,13 cases without significant improvement in lower extremity numbness,2 cases with reduced lower extremity numbness,3 cases with reduced urination and defecation function disturbance and 1 case not recovered.There was no recurrence of tumor.(3) There were 8 lipoma patients who were cured and discharged without urination and defecation function disturbance.Life was basically self-sustaining.(4) There were 9 cases of hemangioblastoma with significant improvement in spinal cord function,5 cases without postoperative pain symptoms and 1 case with significant improvement in pain degree.(5) There were 6 cases of ependymoma,2 cases with significant reduction on limb numbness symptoms,1 case with urinary retention after surgery.There was no significant change in muscle strength of the 2 cases before and after surgery.Conclusions The clinical effect of surgical operation of congenital tumor in conus medullaris position is clear.Combined with imaging examination and attention to surgical precautions,the surgical treatment effect of congenital tumors in the conus region of the spinal cord can be effectively improved.

Isolation and characterization of five novel mini-M conotoxins from the venom of mollusk-hunter snail Conus bandanus

Objective: To determine the new M-superfamily conotoxins from molluscivorous snail Conus bandanus in Vietnam. Methods: Conus bandanus venom was fractionated and purified on HPLC system with an analytical reversed-phase C18 column in order to screen small conotoxins. The primary structure of peptide was analyzed by matrix-assisted laser desorption/ionization time of flight tandem mass spectrometry using collision-induced dissociation and confirmed by Edman's degradation method. Results: Five new conotoxins were biochemically characterized from the crude venom of the mollusk-hunting cone snail Conus bandanus, which were collected at Ke Ga reef of the Nha Trang Bay (Vietnam). Each conotoxin had 15 or 16 amino acid residues and shared the same characteristic cysteine framework V as-CC-C-C-CC-. They were termed as Bn3b, Bn3c, Bn3d, Bn3e and Bn3f following the conotoxins nomenclature. Conclusions: The conotoxins Bn3b, Bn3e, and Bn3f are categorized in the mini-M conotoxins of the M1 branch, while conotoxins Bn3c and Bn3d are categorized in the mini-M conotoxins of the M2 branch. The homological analysis reveals that these conotoxins could serve as promising probe compounds for voltage-gated sodium channels.

Influence of age, sex, height and lumber stenosis on the position of the conus medullaris in adults / Influencia de la edad, sexo, altura y estenosis lumbar en la posición del cono medular en adultos

Anatomical orientation of the termination level of Conus Medullaris (CM) has imperative role clinically for anesthetists and neurosurgeons which is considered as an objective guide to perform spinal anesthesia and spinal punctures circumspectly with less chance to have serious injuries. The current retrospective study was carried on to determine the location of the CM and how its termination level can be influenced by age, sex, height and lumber stenosis spine disease. The study included 462 participants that consisted of 199 men and 263 women range from 21 to 80 years of age and height range between 150-190 cm. Also, it included 150 lumber stenosis patients. The location of the CM was imaged using a series of magnetic resonance images (MRI) for the lumbosacral spine at different levels including, T12, T12-L1, L1, L1-L2, and L2. The measurements revealed inconsiderable differences in the CM termination level in relation to age, sex and height in a healthy study population. Moreover, the results showed insignificant differences in the CM termination level between men and women whether they are healthy or having lumbar spinal stenosis. In conclusion, the most common level of CM termination is at L1 followed by L1-L2. It is safe to perform a lumbar neuraxial procedures at the level of L3-L4.

La orientación anatómica del nivel de terminación del Conus medullaris (CM) tiene un importante papel clínico para los anestesistas y neurocirujanos, que se considera una guía objetiva para realizar la anestesia espinal y las punciones de la columna circunspectivamente con menos posibilidades de provocar lesiones graves. Se llevó a cabo un estudio retrospectivo para determinar la ubicación del CM y cómo su nivel de terminación puede verse afectado por la edad, el sexo, la altura y una patología de la columna vertebral, la estenosis lumbar. El estudio incluyó 462 participantes que consistían en 199 hombres y 263 mujeres de 21 a 80 años de edad y una altura de entre 150-190 cm. Además, se incluyeron 150 pacientes con estenosis lumbar. La ubicación del CM se determinó mediante una serie de imágenes de resonancia magnética (RM) de la columna lumbosacra a diferentes niveles, incluidos T12, T12-L1, L1, L1-L2 y L2. Las mediciones revelaron diferencias considerables en el nivel de terminación de CM en relación con la edad, el sexo o la altura en una población de estudio saludable. Además, los resultados mostraron diferencias poco significativas en el nivel de terminación de CM entre hombres y mujeres, sanos o con estenosis espinal lumbar. En conclusión, se encontró que el nivel más común de terminación del CM es L1 seguido de L1-L2, considerándose seguro realizar procedimientos neuroaxiales lumbares a nivel de L3-L4.

Magnetic Resonance Imaging Observations of the Conus Medullaris in a Korean Population

STUDY DESIGN: Retrospective study (level of evidence: level 3). PURPOSE: To study the anatomy of the conus medullaris in Koreans. OVERVIEW OF LITERATURE: The anatomical position of the conus medullaris is well-documented in anatomy textbooks; however, the shape of the conus in the canal rarely described. Furthermore, to our knowledge, no study in Korea has not yet assessed the shape of the conus as well as its position in the canal via cadavaric dissection and/or magnetic resonance imaging (MRI). METHODS: MRI findings of 189 Korean patients aged 2–94 years (93 men and 94 women) were assessed. No subjects from other ethnicities were included. The method proposed by Arai and colleagues was used to assess the termination point and shape of the conus in the canal. The position of the intervertebral disc trisection of the vertebral body closest to the tip of the conus was recorded at the canal level. RESULTS: The tip of the conus medullaris was positioned from the upper T12 body to the L2–L3 disc, mostly in L1 bodies (52.4%), followed by the L2 bodies (22.5%), the L1–L2 disc, and the L2–L3 disc (1.1%). The shape of the conus was classified as type A in 74 (39.6%), type B in 58 (31%), and type C in 55 patients (29.4%). The conus did not terminate at the L3 body in any patient. In the first decade ones (five children) conus positioned rather lowly from L1 bodies to L2–L3 disc, and no type A conus shape, and mostly type B (80%). CONCLUSIONS: The conus medullaris was positioned mostly in the lower one-third of L1 and it in the first decades terminated lowly. No type A in the first decade one, and type B was mostly frequently formed which was followed by type C.

Conus Medullaris Syndrome Due to Posterior Spinal Artery Infarction

A 77-year-old female with a history of osteoarthritis visited our clinic complaining of lower back pain, paresthesia in both legs, and voiding difficulty. Her pain and temperature sensations were diminished below the L1 dermatome, and proprioception was decreased in both feet. The findings of a routine laboratory workup, echocardiogram, and cerebrospinal fluid studies were normal. Spine magnetic resonance imaging revealed high T2-weighted signal intensities and diffusion restriction in the posterior conus medullaris. The patient was diagnosed and treated for posterior spinal artery infarction.

Conus Medullaris Levels on Ultrasonography in Term Newborns : Normal Levels and Dermatological Findings

OBJECTIVE: Ultrasonography (US) is the most non-invasive, safe, and, especially in the period of infancy, best method for visualizing and examining the spinal cord. Furthermore, US is the primary work-up for development of the spinal canal, and for follow-up on issues relating to subcutaneous tissues, bone development, and the spinal cord. Conus medullaris terminates at the second lumbar vertebra, according to a consensus in the literature. METHODS: Healthy children under the age of 6 months who were admitted to the radiology clinic for routine USG follow-ups between the dates of March 2012 to December 2014 were included in this study. RESULTS: Our study includes data from 1125 lumbosacral ultrasounds. The terminal point of the conus level of the attended infants, superior, middle part, inferior of the vertebrae L1, L2, and L3. Furthermore, the termination of the discal distance ratio did not differ significantly between genders. CONCLUSION: Therefore, according to our results, gender is not an influencing factor in the termination of the spinal cord. Based on the study we performed, as well as the previous literature, in infants without a recognized spinal pathology, the spinal cord is detected below the vertebra L3.

Conus Medullaris Levels on Ultrasonography in Term Newborns : Normal Levels and Dermatological Findings

OBJECTIVE: Ultrasonography (US) is the most non-invasive, safe, and, especially in the period of infancy, best method for visualizing and examining the spinal cord. Furthermore, US is the primary work-up for development of the spinal canal, and for follow-up on issues relating to subcutaneous tissues, bone development, and the spinal cord. Conus medullaris terminates at the second lumbar vertebra, according to a consensus in the literature.METHODS: Healthy children under the age of 6 months who were admitted to the radiology clinic for routine USG follow-ups between the dates of March 2012 to December 2014 were included in this study.RESULTS: Our study includes data from 1125 lumbosacral ultrasounds. The terminal point of the conus level of the attended infants, superior, middle part, inferior of the vertebrae L1, L2, and L3. Furthermore, the termination of the discal distance ratio did not differ significantly between genders.CONCLUSION: Therefore, according to our results, gender is not an influencing factor in the termination of the spinal cord. Based on the study we performed, as well as the previous literature, in infants without a recognized spinal pathology, the spinal cord is detected below the vertebra L3.

Trifurcation of right coronary artery and its huge right ventricular branch: can it be hazardous? / 대한해부학회지

The objective of this case report is to alert the cardiologists and radiologists about the possibility of an extremely rare trifurcation of the right coronary artery. During dissection classes, an early trifurcation of the right coronary artery (RCA) was observed in an adult male cadaver aged approximately 65 years. The RCA had a normal origin from the anterior aortic sinus. After a course of just 2 mm, it trifurcated into a conus artery, a huge right ventricular branch and then a main continuation of the RCA. The conus artery entered the myocardium of the conus after a short course. The huge ventricular branch had a downward and left course almost till the apex of the heart. Right marginal artery was absent. No other vascular variations of heart were observed apart from this. Knowledge of this trifurcation could be useful in coronary angioplasty and bypass procedures.

The new approach in the location of the fetal conus medullaris and its application in tethered cord syndrome / 中华超声影像学杂志

Objective To evaluate the position of the fetal conus medullaris during pregnancy and its value in detecting tethered cord syndrome(TCS). Methods Nine hundred and seventy-four normal fetuses and 46 fetuses with TCS between 15 and 41 weeks gestation were involved in the study.Parameters D 1 (the distance between the end of the conus medullaris and the caudal edge of last vertebral body ossification center) and D2 (the distance from the end of the conus medullaris to the caudal skin namely the intersection point of the extending line of D1 and the skin) were measured in the caudal midsagittal plane of the spine. Sixty normal fetuses were chosed randomly for interobserver variability.Correlation analysis between these two parameters and gestational age(GA) were conducted and the normal reference value of these parameters were calculated in normal group. The ratios of growth parameters ( Biparietal diameter, Head circumference,Abdominal circumference,Femur length) to D1 and D2 were calculated separately to observe the difference of the ratios between two groups. All the parameters and ratios of normal fetuses were compared with that of TCS cases.Results There was no significant difference in D1 and D2 between two observers.A significant linear correlation between the parameters and GA was found in normal group,linear regression equations were D1=0.251 GA -2.265 cm (R2=0.926,P <0.01) and D2=0.267 GA -1.812 cm(R2=0.928,P <0.01),respectively.D1 and D2 were much lower in normal group than in abnormal group (all P <0.01). The ratios of the growth parameters to D1 and D2 were relatively stable and had statistically differences between two groups in different gestational age. Conclusions The methods that determination of D1 and D2 are simple and feasible,and could help to the prenatal diagnosis of TCS.

Study of recognition of atlanto-axial intervertebral space for the localization of fetal vertebrae with three-dimensional ultrasound / 中华超声影像学杂志

Objective To study the feasibility of visualization of atlanto-axial intervertebral space for the localization of fetal centrums with three-dimensional ultrasound and to explore the relationship of intervertebral space with gestational weeks. Methods A total of 223 cases of normal single pregnancy in the second trimester were enrolled in the study to acquire the 3D volume of fetal spines. The distances between the transverse processes of cervical vertebra were measured in vertical horizontal line.The distance between the first and second cervical vertebra was labeled C1,and then labelled C2,C3,C4,C5 and C6 as follows.Results The successful rate of 3D acquisition of 206 cases was 92.4%.The distance between ICC values of C1 -C6 were 0.985,0.984,0.971,0.956,0.978,0.923,respectively and the consistency data measuring was well.The atlanto-axial intervertebral space was significantly larger than other intervertebral space ( P =0.012) and the mean ratios of C1 to C2 -C6 were 1.41,1.39,1.37,1.40,1.39,respectively, which had no correlation with gestational ages ( P = 0.877,0.915,0.838,0.859,0.908,respectively). Conclusions Visualization of the atlanto-axial intervertebral space with three-dimensional ultrasound is a direct and simple method without any consumption,which can help to quickly locate the axial vertebra and other vertebras and conus medullaris.

Experimental study of insulin receptor change from bladder after conus medullaris injury in rats / 中华显微外科杂志

Objective To observe the change rules of insulin receptor from rat bladders after losing lower cen-tal innervations so as to explore the function of insulin receptor in denervated bladder. Methods From January, 2016 to June, 2017, 40 Sprague-Dawley rats were randomly divided into experimental group and control group,each group was 20. The conus medullaris of rats in experimental group were damaged, and rats in control group received sham opera-tion. The rats in 2 groups were sacrificed at different time after surgery (1 day, 1 week, 1 month, 3 months). Bladder specimens were harvested to perform wet weight measurement and immunohistochemical detection of insulin receptor. Results Corresponding to 1 day, 1 week, 1 month and 3 months after surgery, the bladder wet weight of control group were (0.089±0.022)g, (0.094±0.038)g, (0.106±0.112)g and(0.102±0.048)g, and of experimental group were (0.092± 0.026)g, (0.110 ±0.034)g, (0.538 ±0.098)g and (1.528 ±0.462)g. One month and 3 months after surgery, bladder wet weight of experiment group were significantly increased as compared with those of control group (P<0.05). One day, 1 week, 1 month and 3 months after the operation, the positive rate of insulin receptor expression was 60％, 100％, 100％and 80％. And strongly positive rate was 55％. In control group, the positive rate of insulin receptor expression was 20％, 40％, 40％, and 0％. The expression of insulin receptor in experimental group was significantly higher than that in con-trol group in every stage(P<0.05). Conclusion The expression of insulin receptor is significantly increased after den-ervation of bladder. The defections of insulin receptor might lead to apoptosis and muscle wasting after denervation. Re-store insulin receptor function might be key point to prevent bladder tissue from irreversible damage.

Three-dimensional ultrasound volume contrast imaging and tomography ultrasound imaging techniques in observing fetal tethered cord / 中国医学影像技术

Objective To evaluate the value of three-dimensional ultrasound volume contrast imaging (VCI) and tomo graphy ultrasound imaging (TUI) techniques in observing fetal spinal conus medullaris (CM) position and lumbar enlargement of spinal cord morphologic changes,for assessment of tethered cord (TC).Methods Totally 17 abnormal fetuses of spinal diseases combined with TC (abnormal group) were examined by three dimensional ultrasound VCI and TUI techniques.The position of CM was recorded,and the transverse and anteroposterior diameters of lumbar enlargement of spinal cord were measured and compared with 300 cases of normal fetuses (normal group).Results As the growth of the gestational age (CA),CM terminal position increased.All the ends of CM located at L3 or L3 above level in normal.The transverse and anteroposterior diameters of lumbar enlargement in normal group showed good linear relationship with GA.Transverse diameter (mm) =0.677+0.147 ×GA (R2 =0.836,P＜0.05),anteroposterior diameter (mm)-0.994+ 0.152× GA (R2=0.894,P＜0.05).Compared with the corresponding GA fetuses in normal group,the anteroposterior diameter of lumbar enlargement decreased in abnormal group (P=0.002),while no statistical difference of the transverse diameter was found between the two groups (P=0.082).Conclusion Position of CM and lumbar enlargement measure ment can provide valuable reference information for clinical prenatal diagnosis of fetal spinal TC.