Long-term follow-up after aortic valve replacement with a small aortic prosthesis.

Although aortic valve replacement (AVR) is an effective treatment for patients with aortic valvular disease, the implantation of a small aortic prosthesis may result in residual left ventricular outflow stenosis and transvalvular gradient. In this study, the outcome in the long-term period of patients treated with a small aortic prosthesis was analyzed retrospectively. Twenty-four patients with AVR were divided into two groups, group A and group B. Group A consisted of 16 patients with 21 mm-sized prosthetic valves, and group B consisted of 8 patients with 19 or 16 mm-sized prosthetic valves. There were no significant differences in preoperative cardiac function or operative procedure in the two groups. The mean follow-up period (months) was 55.0 in group A and 51.3 in group B. RESULTS: One patient died of cerebral infarction in group A. There were no significant differences in cardiothoracic ratio (CTR), left ventricular ejection fraction (LVEF), and left ventricular mass index (LVMI) between the two groups. Postoperative physical activity according to the New York Heart Association (NYHA) classification showed no significant differences in the two groups. Despite using a small prostheses for AVR, the postoperative course was good in the long-term period, although careful follow-up is necessary.     

Clinical Outcome of Cytoreductive Surgery Prior to Bevacizumab for Patients with Recurrent Glioblastoma: A Single-center Retrospective Analysis

Bevacizumab (BEV) is a key anti-angiogenic agent used in the treatment for recurrent glioblastoma multiforme (GBM). The aim of this study was to investigate whether cytoreductive surgery prior to treatment with BEV contributes to prolongation of survival for patients with recurrent GBM. We retrospectively analyzed the treatment outcomes of 124 patients with recurrent GBM who were initially treated with the Stupp protocol between 2006 and 2019. Given that BEV has only been available in Japan since 2013, we grouped the patients into two groups according to the time of first recurrence: the pre-BEV group (N = 51) included patients who had recurrence before BEV approval, and the BEV group (N = 73) included patients with recurrence after BEV approval. The overall survival after first recurrence (OS-R) was analyzed according to the treatment strategy. Among 124 patients, 27 patients (19.4%) received cytoreductive surgery. There were nine cases in the pre-BEV group and 18 cases in the BEV group. Although the mean extent of resection for both groups was almost equal, OS-R was significantly different. The median OS-R was 8.1 m in the pre-BEV group and 16.3 m in the BEV group (P = 0.007). Multivariate analysis revealed that the unavailability of BEV postoperatively (P = 0.03) and decreasing performance status by surgery (P = 0.01) were significant poor prognostic factors for survival after surgery. With the advent of BEV, cytoreductive surgery might provide superior survival benefit at the time of GBM recurrence, especially in cases where surgery can be performed without deteriorating the patient’s condition.     

Telemedicine in neurosurgery using international digital telephone services between Japan and Malaysia--technical note

A new image transmission and teleconference system using international digital telephone services was established between Japan and Malaysia. This new system consists of an ordinary personal computer, image scanner, and terminal adapter for digital telephone lines. The quality of images transferred using this system was high enough for diagnosis and discussion except for images such as radiographs requiring huge data transfer. Transmission of one image took approximately 20 seconds. The cost performance was almost equal to the conventional mailing system. The most remarkable advantage of this new system is the high quality of transferred images, the cost and time performance, and security of the medical information. New communication systems using international digital networks including the internet may allow re-distribution of medical resources between advanced countries and developing countries in neurosurgery.     

Rebound alkalosis and persistent lactate: multinuclear (1H, 13C, 31P) NMR spectroscopic studies in rats

Intracellular pH levels of infarcted brain determined by phosphorus-31 nuclear magnetic resonance (NMR) spectroscopy disclosed a notable phenomenon. The acidotic brain pH seen in the acute stage of infarction was observed to rebound into the alkalotic range in the subacute phase before returning to the normal range in the chronic phase. This "rebound alkalosis" which was usually observed between the 24th and the 48th hour after experimental induction of infarction in rats was accompanied by significant lactate levels as detected by proton NMR spectroscopy. Analysis of the satellite methyl resonance of 13C-lactate using high-resolution proton NMR spectroscopy after 13C-glucose infusion indicated that no lactate was produced in the subacute phase of infarction and that the lactate detected during this phase must have been generated prior to this phase of infarction.     

Improved PCR amplification for molecular analysis using DNA from long-term preserved formalin-fixed,paraffin-embedded lung cancer tissue specimens

Archival tissue specimens are valuable resources of materials for molecular biological analyses in retrospective studies, especially for rare diseases or those associated with exposure to uncommon environmental events. Although successful amplification with PCR is essential for analysis of DNA extracted from archival formalin-fixed, paraffin-embedded (FFPE) tissue specimens, we have often encountered problems with poor PCR amplification of target fragments. To overcome this, we examined whether heat treatment in alkaline solution could efficiently restore the PCR template activity of DNA that had already been extracted from FFPE lung cancer tissue specimens. The effect of the heat treatment was assessed by PCR for the TP53 gene and other lung cancer-related gene loci. The heat treatment of DNA samples in borate buffer resulted in successful PCR amplification of DNA fragments ranging from 91 to 152 bp. This technique for restoration of template activity of DNA for PCR amplification is very simple and economical, and requires no special apparatus, so it may be applicable for molecular analysis of DNA samples from FFPE tissue specimens at various laboratories.     

Inhibition of growth and induction of apoptosis by all-trans retinoic acid in lymphoid cell lines transfected with the PML/RARα fusion gene

The interaction of an exogenous PML/RARα fusion gene associated with acute promyelocytic leukaemia, with all- trans retinoic acid (ATRA) was examined in two lymphoid cell lines. L1210 and MOLT-4 cells were transfected with PML/RARα cDNA in the expression vector pGD and stable transformants (L1210 PML/RAR α and MOLT-4 PML/RAR α) were selected with G418. ATRA inhibited the growth of these stable transformants, as assessed by [³H]thymidine incorporation, in a dose-dependent manner, but had no effect on the growth of control cells stably transformed with neomycin resistant gene alone. ATRA also induced apoptosis, as assessed by fragmentation of genomic DNA, in L1210 PML/RAR α and MOLT-4 PML/RAR α cells but not in control cells. The exogenous PML/RARα fusion gene therefore probably mediates the effects of ATRA on cell growth and apoptosis in these cell lines.     

CD3 down-regulating factor in sera and culture supernatants of leukaemic cells from patients with adult T cell leukaemia

Immunological abnormality of T lymphocytes in patients with adult T cell leukaemia (ATL) is characterized by abnormal expression of the 55 kD chain of the receptor for interleukin 2 (IL-2R/p55) (Tac), and the down-regulation of CD 3 expression. Using serum and culture supernatants of leukaemic cells from ATL patients (Group A) whose CD 3 expression was down-regulated and those (Group B) whose CD 3 was not low, the possible mechanism of CD 3 down-regulation on ATL cells was discussed. When PBMC from normal individuals were cultured with sera from ATL patients for 24 h, CD 3 expression revealed by mean fluorescent intensity (MFI) was down-regulated by sera from ATL patients in Group A (MFI: Pt 1 = 51.6 ± 4.5, Pt 2 = 48.0 ± 6.9, control = 96.5 ± 6.6), not by sera from patients in Group B (MFI: Pt 3 = 105.5 ± 7.9, Pt 4 = 102.5 ± 8.3, control = 96.5 ± 6.6). When normal PBMC were cultured with supernatants of leukaemic cells from ATL patients in Group A, this CD 3 down-regulating activity was also detected (MFI: Pt 1 = 78.0 ± 10.2, Pt 2 = 70.6 ± 8.7, control = 94.0 ± 6.6). By using gel-chromatography, the fractionated supernatants from ATL patients in Group A decreased CD 3 expression of normal PBMC significantly (MFI: Pt 1 = 22.9 ± 5.8, Pt 2 = 28.8 ± 7.4, control = 92.1 ± 9.6). This CD 3 down-regulating activity in fractionated supernatant was not inhibited by any lymphokine antibodies, anti-IL-1α antibody (Ab), anti-IL-1B Ab, anti-IL-2 Ab, anti-IL-3 Ab, anti-IL-4 Ab, anti-IL-6 Ab, anti-TNF-α Ab and anti-IFN-γ Ab. Any known cytokines (IL-1, IL-2, IL-3, IL-4, IL-6, TNF-α and IFN-γ) could not modulate CD 3 expression of normal PBMC. These findings suggested that there are novel factor(s) with CD 3 down-regulating activity in the serum and culture supernatant of ATL patient and those factor(s) are involved in progression of ATL.     

Temperature changes caused by the difference in the distance between the ultrasound transducer and bone during 1?mhz and 3?mhz continuous ultrasound: a phantom study

[Purpose] This study aimed to use a thermograph to observe temperature changes caused by different distances between an ultrasound transducer and bone during 1 MHz and 3 MHz continuous ultrasound emission on a phantom. [Materials and Methods] We observed the distribution of temperature elevations on a phantom consisting of pig ribs and tissue-mimicking material. One megahertz and 3 MHz ultrasound were delivered at 2.0 W/cm² for 5 minutes. To record the temperature changes on the phantom, we took a screenshot of the thermograph with a digital camera every 20 seconds. [Results] With 1 MHz ultrasound at the distances of 2 and 3 cm, the temperature elevation near the bone was higher than that near the transducer. However, with 3 MHz ultrasound, the temperature elevation was higher near the transducer rather than near the bone. At this point, we consider that there is a possibility of heat injury to internal organs in spite of there being no elevation of skin temperature. [Conclusion] When performing ultrasonic therapy, not only should the frequency be taken into consideration, but also the influence of the absorption coefficient and the reflection of the tissue. We visually confirmed the thermal ultrasound effect by thermography. Special attention to the temperature elevation of the internal organs is necessary to avoid injuries.Key words: Ultrasound, Thermal effect, Thermography