Objective To assess subendocardial systolic circumferential strain(CS),radial strain(RS)and radial displacement(RD)of left ventricle(LV)in short-axis view and LV global systolic function in open-chest canine model with acute myocardial ischemia using velocity vector imaging(VVI),and to establish their spatial correlationships.Methods Left anterior descending coronary artery(LAD)was ligated for 20 minutes to induce acute myocardial ischemia in 12 open-chest canine model.At baseline and 20 minutes after ischemia,two-dimensional dynamic gray-scale images of three standard left ventricular short-axis views at the levels of mitral annulus,papillary muscle and apex and the images of LV apical fourchamber and two-chamber view were acquired and transfefred to VVI workstation for off-line analysis.Peak systolic CS,RS and RD of eighteen segments and of three global short-axis sections of LV were measured at subendocardium.and LV ejection fraction(LVEF)and stroke volume(SV)were calculated using Simpson's method.The differences and correlationships were analyzed between them.Resuls Compared with the value at baseline,LVEF decreased significantly(P＜0.05)after ischemia.The peak systolic subendocardial CS,RS and RD of the affected segments,global CS,RD at papillary muscle and apex views and global RS at apex view were significantly lower than those at baseline after ischemia(P＜0.05).There was a good linear correlationship between the peak systolic CS and RD of 17 segments(except the middle segment of LV lateral wall after ischemia)and each global short-axis level before and after ischemia(r=0.662-0.995,P＜0.05,P＜0.01 or P＜0.001),The peak systolic RS of six segments and each global short-axis level(except the apex level at baseline)was correlated with RD(r=0.580-0.916,P＜0.05,P＜0.01 or P＜0.001);There was not statistical correlationship between global RDs and SV as well as LVEF.Conclusions Subendocardial circumferential strain and radial displacement may sensitively reflect the changes of regional and global myocardial systolic function induced by acute myocardial ischemia.The significant correlationship between subendocardial circumferential systolic strain and radial displacement might indicate that circumferential deformation of myocardium result in the changes of the radial displacement mainly.

Objeetive To evaluate the changes of left ventricular(LV) global and segmental volume, LV outlet pressure and their co-relationship, and to access LV global and segmental systolic function and mechanical asynchrony in different LV electro-mechanical patterns using full volume three-dimensional echocardiography(3DE). Methods Nineteen open-chest canine models were employed for the acquirement of LV full volume dynamic 3DE imaging during right atrial appendage (RAA), right ventricular apical (RVA), LV lateral wall(LVL) and LV apical(LVA). LV outlet end-systolic pressure(ESP) was recorded simultaneously. End-systolic volume (ESV), end-diastolic volume (EDV), global and segmental ejection fraction(EF) and systolic dyssynchrony index(SDI) of LV were measured and calculated using a dedicated workstation. The average ascending rate of LV pressure during systole(+ dp/dt) and the average descending systolic pressure(ESP), + dp/dt and - dp/dt during RVA pacing were lower than those during RAA pacing (P <0.05). SDI during RVA pacing was higher than that during RAA pacing(P<0.05). ESP, + dp/dtand - dp/dt during LVL and LVA pacing were lower than those during RAA pacing (P <0.05). There and LVA pacing was higher than that during RVA pacing (P <0.05),SD1 during LVL pacing was lower than that during RVA pacing (P <0.05), there was no significant difference of SDI between RVA and LVA and LVL pacing. Segmental EF of septum and apex during LVI. pacing were higher than those during LVA pacing (P <0.05). @Segmental EF of anterior and post septum and all apical segments (except lateral wall) during RVA pacing were lower than those during RAA pacing (P <0.05). Segmental EF of lateral and anterior wall during I.VI. pacing were lower than those during RAA pacing (P <0.05). Segmental EF of anterior wall and anterior septum during LVA pacing were lower than those during RAA parameters. Conclusions The global and minority segmental systolic function of LV during RAA pacing could be reduced compared with normal sinus rhythm. All the ventricular pacing worsen LV systolic and diastolic function compared with RAA pacing. LV systolic function during LVL pacing was superior to RVA pacing. During ventricular pacing,the systolic function at nearby segments of the pacing site was depressed.

Objective To evaluate the changes of peak segmental and transmural radial displacement (RD) of left ventricle(LV) during acute myocardial ischemia with different LV pacing patterns. Methods Left anterior descending coronary artery (LAD) was ligated to induce acute myocardial ischemia in open-chest Beagle canine models ( n=10). Two-dimensional gray-scale images with overlaid tissue Doppler velocity imaging in three standard LV short-axis views were acquired with different pacing patterns in a randomized sequence in three complete cardiac cycles. Parameters including peak RD, peak RD time(RD-Tc) ,the standard deviation of TC(RD-TSD) of 12 segments and their myocardial layers(subend,mid,subepi) were measured and analyzed using TDI-Q workstation. Results ① There were no significant differences of peak RD between three myocardial layers of LV wall in each different pacing pattern group;There were no significant difference of peak RD from segments and transmural layers among the different LV pacing patterns. ②With acute myocardial ischemia the RD correlation of LV lateral pacing( LVL-P) and LV border pacing(LVB-P) patterns were higher than that of LV apical pacing(LVA-P) pattern between global segment and its subend, mid, subepi. ③ RD-Tc of 12 LV segments and their subend, mid, subepi appeared after T wave and there were no significant differences of RD-Tc among different LV pacing patterns. ④RD-TSD of the corresponding segments during LVL-P,LVA-P and LVB-P patterns were significant lower than those during acute yocardial ischemia(P<0. 05). Conclusions The existed RD correlation of LVA-P between subend.mid, subepi and the segment were lowest among the different ischemic LV pacing patterns; the synchronization of transmural RD could be recovered partly with LVL-P, LVA-P and LVB-P patterns. The echocardiographic study of LV transmural RD might be useful to reveal the segmental and the transmural myocardial mechanical state with different LV pacing patterns during acute ischemia in detail.

Objective To study the Hoxd 13 gene expression in the children with anorectal malformation (CAM)and normal children, and to explore the relationship between Hoxd 13 gene and CAM. Methods Hoxd 13 gene mRNAexpression was detected by RT- PCR in the rectal pouch in both 16 cases of anorectal malformations and 5 normalchildren. Results The expression level of Hoxd 13 gene mRNA was significantly higher in normal children than that inchildren with CAM (0.32+0.26 vs 0.73+0.10), ( P ＜0.01). Conclusions Hoxd 13 gene expression may beinvolved in the pathogenesis of anorectal malformation.

OBJECTIVETo investigate the structural and functional changes of internal anal sphincter (IAS) in children with functional constipation (FC), and to evaluate the association between the thickness of IAS and the severity of clinical symptoms.

METHODSA total of 35 children with FC(constipation group,17 with incontinence) between June 2008 and December 2008 at the Shengjing Hospital of China Medical University were evaluated using anal manometry and endosonography. These patients were compared to 23 hospitalized children who were excluded for digestive and endocrinal diseases(control group). A validated symptom score(SS) was used to assess the severity of symptoms. The sum of SS ranged between 0 and 65.

RESULTSAnorectal manometry showed reflex relaxation of IAS in response to distension of rectal balloon in all patients. Rectal perceptional threshold in FC group was significantly higher than that in the controls[(42.4 ± 19.5) ml vs.(29.1 ± 15.6) ml, P<0.05]. The lowest volume for inducing reflex relaxation of IAS was significantly higher than that in the controls [(55.6 ± 31.6) ml vs.(30.5 ±13.8) ml, P<0.05]. The thickening of IAS was noted in all the patients[(3.8 ± 1.7) mm vs.(2.5 ± 1.0) mm, P<0.05]. However, there was no significant difference between FC and control in median resting anal sphincter pressure[(170.8 ± 62.3) mm Hg vs. (161.3 ± 51.1) mm Hg, P>0.05]. The median symptom score was 9.3 ± 4.3 in the FC group. The thickness of IAS correlated significantly with total symptom severity score(r=0.407, P<0.05). There was no correlation between thickness of IAS and age, sex, or duration of disease(P>0.05).

CONCLUSIONSStructural and functional changes of internal anal sphincter exist in children with functional constipation. The thickness of internal anal sphincter correlates significantly with symptom severity.

Anal Canal ; diagnostic imaging ; physiopathology ; Child ; Child, Preschool ; Constipation ; diagnostic imaging ; physiopathology ; Endosonography ; Female ; Humans ; Male

OBJECTIVEUndried silver-hydroxyapatite-titania (Ag-nHA-nTiO2) nanoparticles slurry was used to make membrane with polyamide 66 (PA66) by co-polymerization method. The purpose of this study is to test the physical and chemical characteristics and antibacterial ability.

METHODSThe morphology, chemical components and structures of the membrane were characterized by atomic absorption spectrometer (AAS), X-ray diffraction (XRD), scanning electron microscope (SEM) and energy-dispersive X-ray analysis (EDX). Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), Porphyromonas gingivalis (P. gingivalis), Fusobacterium nucleatum (F. nucleatum) and Streptococcus mutans (S. mutans) were utilized to test the antibacterial effect.

RESULTSXRD results demonstrated that the membrane have characteristic diffraction peaks of pure hydroxyapatite (HA). A homogeneous distribution of the Ca, P, Ti and Ag element in the membrane was confirmed by EDX. Both surface and section showed porous structure which was confirmed by SEM and the average hole size was 20-30 microm. The bacteria assay reflected to the antibacterial effect, 50.10% of S. aureus and 56.31% of E. coli were killed. However, 91.84% of P. gingivalis, 90.64% of F. nucleatum and 90.49% of S. mutans were killed and pictures of SEM showed obviously fewer cells on the surface.

CONCLUSIONThe nanocomposite membrane could be one of the bioactive materials with antibacterial properties for oral guided bone regeneration technique.

Anti-Bacterial Agents ; Bone Regeneration ; Durapatite ; Escherichia coli ; Nanocomposites ; Nylons ; Silver ; Staphylococcus aureus ; Titanium ; X-Ray Diffraction

OBJECTIVEThe short-term efficacy of the transanal one-stage endorectal pull through operation for Hirschsprung's disease is satisfactory. However the long-term outcome of anorectal function has not been fully understood. The aim of this study was to evaluate the stooling pattern, colonic motility and anal sphincter performance after transanal one-stage pull through operation in children with Hirschsprung's disease.

METHODSFifty-eight children who underwent transanal one-stage pull through operation for Hirschsprung's disease were followed up. The mean follow-up duration was 15.8 months (range, 6-24 months). The stooling patterns of the patients were investigated by the informed questionnaire. Barium enema, defecography, total and segmental colonic transit time and the anorectal vector manometry were performed. Thirty- three healthy children were used as controls.

RESULTSMost of patients had normal stool consistency and frequency. Postoperative enterocolitis occurred in 3 patients, and constipation was found in five patients. Postoperative soiling was observed in 9 patients. None of the 58 patients had incontinence, cuff infection, anastomotic leak and mortality. The barium enema showed that the configuration of the colon recovered well in most of patients. Postopertive defecography showed the anorectal angle of all the patients was open, fixed and bigger than that of preoperation and the healthy controls (P < 0.01). Postoperatively, the mean total gastrointestinal transit time (TGITT), the left colonic transit time (LCTT) and rectosigmoid colonic transit time (RSTT) in the 58 patients were significantly shorter than preoperatively (P < 0.01) and were similar to those of the control group. The rectoanal inhibitory reflex was regained in 5 patients. The anal maximal pressure of the patients with constipation in resting and squeezing condition were significantly higher than those of the asymptomatic patients and controls (P < 0.05). The vector volume (VV) and vector symmetric index (VSI) in patients with soiling were significantly lower than those in preoperation and the controls (P < 0.05). The VSI in the patients with constipation was significantly higher compared with the controls (P < 0.05).

CONCLUSIONSThe stooling function, colonic motility and anal sphincter performance manifest well in most of the patients after the transanal endorectal pull through operation for Hirschsprung's disease. Stooling disorders in few cases are probably related to decrease or disappearance of the sigmoid loops, dysfunction of the "neorectosigmoid", an open and fixed anorectal angle and achalasia of the internal anal sphincter.

Child, Preschool ; Colon ; physiopathology ; Female ; Follow-Up Studies ; Gastrointestinal Transit ; Hirschsprung Disease ; physiopathology ; surgery ; Humans ; Infant ; Male ; Postoperative Complications ; etiology ; Pressure ; Rectum ; physiopathology ; surgery

OBJECTIVEIn the normal embryonic development of anorectum, apoptosis plays an important role. To explore the role of apoptosis in anorectal malformations (ARM), this study investigated cell apoptosis during the cloacal embryonic development in ARM embryos.

METHODSARM embryos were induced by intragastric administration of ethylenethiourea (125 mg/kg) for pregnant rats on embryonic day 10 (E10). The distribution of apoptotic cells in the cloaca was ascertained by hematoxylin and eosin and TUNEL staining in the normal control embryos (n=102) and ARM embryos (n=147) on E13, E13.5, E14, E15 and E16.

RESULTSOn E13, apoptotic cells were detected in the urorectal septum of rat embryos in the control group. With the development of embryos, the number of apoptotic cells in the mesenchyme of urorectal septum gradually increased and a large number of apoptotic cells were seen in the dorsal rectal mesenchyme. On E14, apoptotic cells appeared at the terminal rectum and the dorsal cloacal membrane. On E15, the urorectal septum fused with the cloacal membrane and apoptotic cells in the urorectal septum mesenchyme continuously extended down to the fusion region. Compared with the control group, apoptotic cells in the urorectal septum, the dorsal rectal mesenchyme and the cloacal membrane of the ARM rat embryos were significantly reduced during the embryonic development. The development of the urorectal septum was delayed and it did not fuse with the cloacal membrane in ARM embryos.

CONCLUSIONSDuring the embryonic development of cloaca, abnormal apoptosis in the urorectal septum, the dorsal rectal mesenchyme and the cloacal membrane may be one of the reasons for anorectal malformations. The proper regulation of cell apoptosis may be one of the key mechanisms for normal development of anorectum in the embryonic stage.

Anal Canal ; abnormalities ; Animals ; Apoptosis ; Cloaca ; embryology ; pathology ; Embryonic Development ; Female ; Pregnancy ; Rats ; Rats, Wistar ; Rectum ; abnormalities

OBJECTIVETo investigate the expression of Notch-1 and Jagged-2 in the normal and spastic segments of colon in patients with Hirschsprung disease(HD), and to explore the correlation of Notch-1 and Jagged-2 with pathogenesis of HD.

METHODSFrom 2005 to 2010, resected colon specimens of 30 cases with HD were selected for this study. Normal colonic segments were served as control group, while the transitional and spastic segments as experimental group. Immunohistochemical staining, Western blotting, and RT-PCR were applied to detect the expression of Notch-1 and Jagged-2.

RESULTSA large number of Notch-1 and Jagged-2 positive gangliocytes were observed in the control group, while none was observed in spastic segments. Significantly less Notch-1 and Jagged-2 positive gangliocytes were found in the transitional segments. Western blotting revealed that Notch-1 and Jagged-2 protein levels in spastic segments (0.19±0.02 and 0.13±0.04) were less than that in transitional segments and normal segments (0.58±0.05 and 0.52±0.04, 0.72±0.04 and 0.69±0.04, respectively)(P<0.05). RT-PCR revealed that Notch-1 and Jagged-2 mRNA levels were consistent with protein expression.

CONCLUSIONNotch-1 and Jagged-2 are not expressed in spastic colon segments, which may be associated with the pathogenesis of HD.

Case-Control Studies ; Female ; Hirschsprung Disease ; genetics ; metabolism ; Humans ; Infant ; Intercellular Signaling Peptides and Proteins ; genetics ; Jagged-2 Protein ; Male ; Membrane Proteins ; genetics ; RNA, Messenger ; genetics ; Receptor, Notch1 ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction

OBJECTIVETo determine the total and segmental colonic transit time of normal Chinese children and to explore its value in constipation in children.

METHODSThe subjects involved in this study were divided into 2 groups. One group was control, which had 33 healthy children (21 males and 12 females) aged 2 - 13 years (mean 5 years). The other was constipation group, which had 25 patients (15 males and 10 females) aged 3 - 14 years (mean 7 years) with constipation according to Benninga's criteria. Written informed consent was obtained from the parents of each subject. In this study the simplified method of radio opaque markers was used to determine the total gastrointestinal transit time and segmental colonic transit time of the normal and constipated children, and in part of these patients X-ray defecography was also used.

RESULTSThe total gastrointestinal transit time (TGITT), right colonic transit time (RCTT), left colonic transit time (LCTT) and rectosigmoid colonic transit time (RSTT) of the normal children were 28.7 +/- 7.7 h, 7.5 +/- 3.2 h, 6.5 +/- 3.8 h and 13.4 +/- 5.6 h, respectively. In the constipated children, the TGITT, LCTT and RSTT were significantly longer than those in controls (92.2 +/- 55.5 h vs 28.7 +/- 7.7 h, P < 0.001; 16.9 +/- 12.6 h vs 6.5 +/- 3.8 h, P < 0.01; 61.5 +/- 29.0 h vs 13.4 +/- 5.6 h, P < 0.001), while the RCTT had no significant difference. X-ray defecography demonstrated one rectocele, one perineal descent syndrome and one puborectal muscle syndrome, respectively.

CONCLUSIONThe TGITT, RCTT, LCTT and RSTT of the normal children were 28.7 +/- 7.7 h, 7.5 +/- 3.2 h, 6.5 +/- 3.8 h and 13.4 +/- 5.6 h, respectively. With the segmental colonic transit time, constipation can be divided into four types: slow-transit constipation, outlet obstruction, mixed type and normal transit constipation. X-ray defecography can demonstrate the anatomical or dynamic abnormalities within the anorectal area, with which constipation can be further divided into different subtypes, and combined use of the gastrointestinal transit time and X-ray defecography is of clinical importance in exploration of etiology of constipation.

Adolescent ; Child ; Child, Preschool ; Constipation ; physiopathology ; Defecography ; methods ; Female ; Gastrointestinal Transit ; Humans ; Male ; Time Factors