The analysis of mitral annular disjunction detected by echocardiography and comparison with previously reported pathological data

Background

Mitral annular disjunction is a structural abnormality of the mitral annulus fibrosus and is pathologically defined by a separation between the atrial wall–mitral valve junction and the left ventricular attachment. Mitral annular disjunction can cause hypermobility of the mitral valve apparatus and is often associated with mitral valve prolapse (MVP). The aim of this study was to investigate the frequency and characteristics of mitral annular disjunction in the patients referred to an echocardiography laboratory and to compare these with previously reported pathological data.

Methods and results

We retrospectively studied 1439 patients (mean age 65 ± 17 years, 58% male) referred to our echocardiography laboratory from 6 January 2014 to 31 March 2014. The echocardiographic parameters were compared between the patients with and without mitral annular disjunction. There were 125 cases (8.7%) with mitral annular disjunction, of which 15 (12%) also had MVP. The number of MVP patients in the group with mitral annular disjunction was significantly larger than in the group without mitral annular disjunction (p < 0.0001). The grade of mitral regurgitation was not significantly different between the two groups.

Conclusions

Mitral annular disjunction was detected not only in patients with a myxomatous mitral valve but also in normal cases. The number of MVPs was significantly larger in patients with mitral annular disjunction than patients without mitral annular disjunction. Further investigation is needed to clarify the clinical significance of the mitral annular disjunction detected by routine echocardiography.

     

Spontaneous closure of a large left ventricular pseudoaneurysm after mitral valve replacement

Left ventricular pseudoaneurysm is a rare, but potentially fatal, condition that generally occurs as a complication of myocardial infarction, infective endocarditis, or cardiac surgery. Surgical repair is the treatment of first choice because of the marked risk of rupture, but deteriorated hemodynamics and complicated procedures to treat the pseudoaneurysm may lead to a high mortality rate. We report a 62-year-old woman with a large left ventricular pseudoaneurysm after mitral valve replacement for rheumatic mitral valve stenosis. Surgical repair was not performed due to the patient’s refusal, but her pseudoaneurysm resolved spontaneously by 2 years after mitral valve replacement. Spontaneous obliteration of a large left ventricular pseudoaneurysm is very rare in a patient on warfarin therapy. This case suggests that a left ventricular pseudoaneurysm with a narrow neck may resolve spontaneously in rare settings.     

Weight gain in childhood and bone mass in female college students

The attainment of maximal peak bone mass early on in life is one of the most important strategies for the prevention of osteoporosis in women. The aim of this study was to clarify the correlation between gains in body size in all growth phases in childhood and adult bone mass in women. The subjects were 86 female first-year university students, aged 18–21 years. We measured the subjects bone mineral content (BMC) and bone mineral density (BMD) at the lumbar spine and the left hip, including the femoral neck, with dual energy X-ray absorptiometry. Each subject was measured for current height and weight. Height and weight at birth, and at 1.5, and 3 years were obtained from each maternity record book, and those between 6 and 18 years were obtained from their school health records. Other information, including physical activity and calcium intake, was obtained through an interview. Bivariate analysis showed that weight gains during the periods from birth to 1.5 years and from 9 to 12 years significantly correlated with both BMC and BMD values at any site. The stepwise method of multiple regression analysis showed that a weight gain during the period from birth to 1.5 years was significantly associated with BMC at the lumbar spine (P = 0.0001) and at the femoral neck (P = 0.0290) and with BMD at the lumbar spine (P = 0.0387). Birth weight was significantly associated with BMC at the lumbar spine (P = 0.0474) and the total hip (P = 0.0352), and weight gain during the period from 9 to 12 years was significantly associated with BMC at the femoral neck (P = 0.0376). In conclusion, birth weight and weight gain in infancy are important determinants of bone mass in young women. Additionally, a girls prepubertal growth spurt is likely to be a key phase for the acquisition of bone mass in relation to body weight. Our findings suggest that osteoporosis prevention programs may need to start very early in the life cycle.     

Surgical treatment of lumbar ossification of the posterior longitudinal ligament. Report of two cases and description of surgical technique

The authors report two cases of patients with lumbar ossification of the posterior longitudinal ligament (OPLL). One patient underwent surgery via the single posterior approach, and the other patient underwent combined anterior-posterior surgery. The authors consider the anterior approach for excision of the ossified lesion to be the most reasonable for treatment of lumbar OPLL. It is extremely important, however, to select the surgical procedure according to the individual patient's condition.     

Developmental study of tethered spinal cord in murine embryos with anorectal malformations

Background/Purpose

Tethered spinal cord is frequently associated with anorectal malformations (ARMs). However, it remains unknown how the tethered spinal cord develops and relates to the severity of ARM. We studied the development of the spinal cord in ARM mouse embryos induced by all-trans retinoic acid (ATRA).

Methods

Pregnant ICR-Slc mice were administered 100 mg/kg of ATRA on the ninth embryonic day (E9.0). Embryonic specimens were obtained from the uteri between E11.0 and E18.5. Midsagittal histologic sections focusing on the spinal cord and pelvis were prepared for immuonhistochemistry specific for neurofilament and Protein Gene Product 9.5 molecules.

Results

More than 98% of ATRA-treated embryos demonstrated ARM with rectourethral or rectocloacal fistula. Normal embryos exhibited progressive ascent of the spinal cord from E14.5. However, in ARM embryos, the distal spinal cord ended with meningomyelocelelike or atypical hamartomatous lesions at E11.5 to E13.5, which later caused stretch force that damaged the spinal cord, resulting in tethered cord between E16.0 and E16.5.

Conclusions

In ATRA-induced ARM mouse embryos, tethered spinal cord was mostly established, accompanied by caudal neural maldevelopment, during early fetal development. This experimental model may be useful for researching detailed neuropathologic conditions in ARM children accompanied with tethered spinal cord.     

The detection of cerebral hypoperfusion with bispectral index monitoring during general anesthesia

We describe a patient in whom the bispectral index (BIS) decreased to 0 during surgery. A 42-yr-old man with chronic renal failure was scheduled to undergo construction of an arteriovenous shunt. He had a history of acute cerebral hemorrhage. An intracranial hematoma had been removed a month earlier with almost complete neurological recovery. He had uncontrolled hypertension. His systolic blood pressure was 180 mm Hg before anesthesia induction. Anesthesia was induced with 100 mg of propofol and 3% sevoflurane. After laryngeal mask insertion, anesthesia was maintained with nitrous oxide 60% in oxygen and sevoflurane. BIS decreased to near 0 on 2 occasions: after anesthesia induction and shortly after the start of the surgery. His systolic blood pressure decreased to 110 mm Hg and BIS increased when his blood pressure was increased to 130-140 mm Hg. The decrease in BIS was suspected to be the result of decreased cerebral blood flow. The systolic blood pressure of 110 mm Hg (mean blood pressure, 80 mm Hg) was probably less than the lower limit of autoregulation. Although BIS has some limitations as a cerebral monitor, it was useful for detecting possible cerebral hypoperfusion in this case.     

Donor cell engraftment in recipient lymphoid tissues after rat limb allograft

BACKGROUND: The movement of cells from a transplanted tissue into the host organs, the so-called systemic chimerism, is a phenomenon known to occur and be associated with the development of immunologic tolerance in allotransplantation cases. The purpose of this study was to identify donor cell engraftment in recipient lymphoid tissues after performing rat hind limb allograft. MATERIALS AND METHODS: Fifty-five whole-limb allotransplantations were performed in sex-mismatched pairs of rats. Syngeneic male Lewis and allogeneic Dark Agouti donors were transplanted to female Lewis recipients. FK506 was used for immunosuppression. Donor male cells could be identified in the recipient female tissues by semiquantitative polymerase chain reaction analysis for a Y chromosome-specific DNA sequence. Chimerism was assessed at 1, 24, and 48 weeks after transplantation. RESULTS: There was no rejection episode in any of the limb grafts. Although levels of chimerism were highly variable in each lymphoid tissue, a gradual increase was noticed in all during the course of time. At 1 week after the transplant period, only intrasplenic chimerism was at high level (1%) in three groups. At 48 weeks after the transplant, all recipients with allografts showed very high level (10%) of chimerism in the bone marrow. Two, two, and two of six recipients showed very high levels in the spleen, lymph node, and liver, respectively, at 48 weeks. Intrathymic chimerism was higher at 24 weeks after transplant rather than at 48 weeks. CONCLUSION: We demonstrated donor cell engraftment into recipient lymphoid tissues after successful whole limb transplantation. We conclude that limb allograft can work as a vascularized carrier for the bone marrow transplantation, provide a continuous source of donor cells and contribute to chimerism in the recipient.     

微型Doppler和内窥镜在脑动脉瘤手术中的应用

目的 探讨Doppler微型探头和硬性神经内窥镜在脑动脉瘤手术中的应用价值.方法 2005 年4月至 2006年7月,96位脑动脉瘤患者在手术中同时应用Doppler和内窥镜,动脉瘤数为107个.Doppler探头的直径为 1.5 mm,频率为 20 MHz;内窥镜有0、30、70三种角度.在动脉瘤夹闭前和(或)夹闭后使用Doppler和神经内窥镜.结果 107个动脉瘤中的39个动脉瘤,内窥镜提供了显微镜所没有提供的信息;19例在内窥镜和Doppler探查后对动脉瘤夹进行了调整,其中10例因瘤颈不完全夹闭, 9例因穿通支受到动脉瘤夹的影响.结论 Doppler和神经内窥镜在动脉瘤手术中具有应用价值,可在夹闭前和(或)夹闭后应用.     

Optical mapping reveals developmental dynamics of Mg2+-/APV-sensitive components of glossopharyngeal glutamatergic EPSPs in the embryonic chick NTS

To examine whether there are any differences in functional organization between the glossopharyngeal nerve (N. IX)- and vagus nerve (N. X)-projecting areas in the nucleus of the tractus solitarius (NTS), we performed optical recording of neural responses evoked by N. IX stimulation in 5- to 9-day-old embryonic chick brain stem preparations and compared the results with those in our previous studies concerning the N. X-related NTS. First, we investigated DL-2-amino-5-phosphonovaleric acid (APV)/Mg2+ sensitivity of the glutamatergic excitatory postsynaptic potentials (EPSPs) in the N. IX-related NTS. In 7- to 9-day-old preparations, we found regional differences in the degree of both the APV-induced reduction and Mg2+-free-induced enhancement of the EPSPs. We constructed developmental maps of spatial patterns of the APV- and Mg2+-sensitive components and showed that functional expression of the N-methyl-D-aspartate (NMDA) receptor dynamically changed during development. Second, we studied initial expression of synaptic functions in the N. IX-related NTS. In 6-day-old preparations, although action potentials alone were usually detected in normal Ringer solution, small EPSPs were elicited in a Mg2+-free solution. This result suggests that the NMDA receptor-mediated synaptic function is latently generated in the N. IX-related NTS at the 6-day-old embryonic stage and that external Mg2+ regulates the onset of synaptic functions. Developmental patterns of APV/Mg2+ sensitivity and the stage of initial expression of the glossopharyngeal EPSP were similar to those of the N. X, suggesting that the developmental sequence of the synaptic function in the NTS is the same for the N. IX- and N. X-related NTS.