Genetic aberrations detected by comparative genomic hybridization in biliary tract cancers

In order to elucidate cytogenetic changes characteristic of biliary tract cancer, we examined the genetic imbalances in 18 biliary tract cancers using comparative genomic hybridization (CGH). The most common sites of increases in copy number, in order of frequency, were 17q (33% of the cases), 5p (28%), 3q (22%), 7p (22%), 8q (22%), and 12p (22%), whereas copy number decreases of 6q (28%), 18q (28%), 4q (22%), 5q (22%), and 9p (22%) were frequent. The average number of chromosomal aberrations was significantly greater in stage IV than in stage III tumors (7.9 vs. 2.2/tumor, p < 0.05). The frequent aberrations detected in this study may be related to the development and/or progression of biliary tract cancers. This is the first report on CGH of biliary tract cancers.

[Granular lymphocyte-proliferative disorder following initiation of protease inhibitor therapy in a patient with acquired immunodeficiency syndrome]

The authors experienced granular lymphocyte-proliferative disorder (GLPD) with increased lymphocyte and CD4 cell counts after HIV treatment with a protease inhibitor indinavir in a 51-year-old male AIDS patient. GLPD proved to be the chronic type, but we could not differentiate whether it was the T-cell type or the NK-cell type. EB virus was found to be activated and its chronic activity was suggested. We should note in this case that EB virus was involved in the GLPD onset and that GLPD followed the treatment with a protease inhibitor.

[Multivariate analyses by quantitative method II of subjective pitch and tonality of tinnitus]

Factors affecting subjective tinnitus pitch and tinnitus tonality were analyzed with the use of the quantitative method II. Ninety-one patients with unilateral tinnitus of a single kind were studied. Major factors affecting subjective tinnitus pitch were pitch matched frequency, age, puerility and impurity of tinnitus tonality, and loudness of tinnitus. In addition, major factors affecting puerility and impurity of tinnitus tonality were pitch matched frequency, loudness of tinnitus, and nature of the test tone. Furthermore, subjective puerility of tinnitus was associated with middle-pitched frequency and high-pitched frequency, and a loudness level of tinnitus between 25 and 49 dB HL. Whereas impurity of tinnitus was related to low-pitched frequency and noise of the test tone. These results may contribute to the clinical evaluation of tinnitus.

p16/MTS1/INK4A gene is frequently inactivated by hypermethylation in childhood acute lymphoblastic leukemia with 11q23 translocation

The p16 gene encoding a specific inhibitor of cyclin-dependent kinases 4 and 6 has been reported to be inactivated at a variety of rates in malignant tumors. We studied frequency and mechanism of inactivation of the p16 gene in various types of childhood acute lymphoblastic leukemia (ALL) using 36 leukemic cell lines established from children (B precursor-ALL, 28; B-ALL/Burkitt's lymphoma, 3; and T-ALL, 5). On Southern blot, homozygous deletions or hemizygous deletions with rearrangement were detected in 14 cell lines. The expression of p16 protein was not observed on Western blot in 18 of 22 cell lines with intact p16 gene, but induced in 16 cell lines after treatment with the demethylating agent, indicating the silencing of the p16 gene by hypermethylation. Of note, the p16 gene was inactivated by hypermethylation of the 5' CpG island in nine of nine cell lines with 11q23 translocation, but was restored with the treatment of the demethylating agent. Partial methylation of the p16 gene was also demonstrated in three of eight primary leukemia samples with this translocation, suggesting that the p16 gene inactivation by hypermethylation might play a role in the leukemogenesis and disease progression of ALL with 11q23 translocation.

[A case of multiple endocrine neoplasia type 2A (MEN2A) with a mutation in the RET gene]

A 44-year-old woman complained of headache and palpitation. Magnetic resonance imaging showed bilateral adrenal tumors 10 x 9 cm in size on the left side and 8 x 4 cm in size on the right side. CT scan revealed a 0.7 x 0.7 cm mass in the thyroid. Hormonal examinations showed high values of urinary cathecholamines and serum calcitonin. DNA sequence analysis of peripheral white blood cells revealed that codon 634 in exon 11 of the RET gene was mutated from TGC (Cys) to TAC (Tyr). From these findings, a diagnosis was made of MEN2A with bilateral adrenal pheochromocytomas and medullary thyroid carcinoma. Bilateral adrenalectomy and thyroidectomy were performed. The same mutation of the RET gene was detected in all her 3 children, in two of whom, early stage medullary thyroid carcinoma was detected and thyroidectomy was performed. DNA analysis of the RET gene was useful for the diagnosis of carriers of MEN2A and the early detection of medullary thyroid carcinoma.

Genetic aberrations detected by comparative genomic hybridization in hepatocellular carcinomas: their relationship to clinicopathological features

To elucidate cytogenetic alterations underlying human hepatocellular carcinomas (HCCs), we used a comparative genomic hybridization (CGH) method to analyze 41 cases of hepatocellular carcinoma (HCC) including 15 well differentiated HCCs, 14 moderately differentiated HCCs, and 12 poorly differentiated HCCs. Of these, 27 patients were chronically infected with hepatitis C virus (HCV), and the remaining patients were positive for hepatitis B virus (HBV). The most common sites of increase in DNA copy number were 1q (78% of the cases) and 8q (66%) with minimal overlapping regions at 1q24-25 and 8q24, respectively. Frequent decreases in copy number were observed at 17p (51%), 16q (46%), 13q13-14 (37%), 4q13-22 (32%), 8p (29%), and 10q (17%). In 6 cases (15%), an amplification was found in the region of 11q13. A gain of 8q24 was significantly associated with well-differentiated HCCs (P<.05), whereas a loss of 13q13-14 and amplification of 11q13 were linked to moderately and poorly differentiated HCCs (P<.01). These observations suggest that a gain of 8q24 is an early event and that a loss of 13q13-14 and amplification of 11q13 are a late event in the course of liver carcinogenesis. A gain of 10q (7/41) was detected exclusively in cases with HCV infection. In contrast, an amplification of 11q13 was preferentially found in HBV-positive HCCs. These findings raise the hypothesis that, although many genetic alterations are basically common to both HCV-positive and HBV-positive tumors, the process of carcinogenesis may be to some extent different between these two types of tumors.

The KOR-SA3544 antigen predominantly expressed on the surface of Philadelphia chromosome-positive acute lymphoblastic leukemia cells is nonspecific cross-reacting antigen-50/90 (CD66c) and invariably expressed in cytoplasm of human leukemia cells

We previously reported a novel monoclonal antibody KOR-SA3544 which predominantly reacted with a surface antigen (sSA3544) expressed on Philadelphia chromosome (Ph1)-positive acute lymphoblastic leukemia (ALL). In the present study, we demonstrate that the antibody specifically recognized nonspecific cross-reacting antigen (NCA)-50/90 (CD66c), one of the carcinoembryonic antigen (CEA)-related glycoproteins encoded by a member of the CEA gene family. In addition, we show that the SA3544 antigen (NCA-50/90) was invariably expressed in cytoplasm of all of the human leukemic cell lines examined (sSA3544-positive B-lymphoid two, sSA3544-negative T or B-lymphoid and non-lymphoid 24) regardless of the presence or absence of surface expression of this antigen. Immunoelectromicroscopic examination revealed that the cytoplasmic antigen was mainly present in granules in sSA3544-positive leukemia cells, whereas it was diffusely present in cytosol in sSA3544-negative leukemia cells. Thus, among members of the CEA family, NCA-50/90 was first demonstrated to be expressed not only on the surface of some leukemia cells, but also in cytoplasm of various types of leukemia cells.

[Efficacy of zonisamide in West syndrome]

The efficacy of zonisamide (ZNS) was studied in 16 patients (11 males, 5 females) with West syndrome (WS), symptomatic in 13 and cryptogenic in 3. They did not respond to pyridoxal phosphate (12 cases) or valproate (16 cases). The mean age of onset of WS was 4.4 (2-9) months. ZNS was administered from 3 to 9 months of age (mean 6.1). Four cases (2 cryptogenic and 2 symptomatic) became seizure free. Two had more than 50% seizure reduction. Ten infants remained unchanged or showed less than 50% seizure reduction. In the 4 responders, the effective dose was 4-8 mg/kg (mean 5.8), and the serum ZNS concentration was 10-21 micrograms/ml (mean 13.8). One had relapse of WS after 4 months. Three with normalized EEG remained seizure-free during the follow-up period (12-26 months). One case developed a transient drowsiness, but no serious side effects were observed. These data suggest ZNS may be regarded as a therapy of choice before synthesized ACTH therapy in the management of WS.

Hepatic uptake of polystyrene microspheres in rats: effect of particle size on intrahepatic distribution

The in vivo disposition of polystyrene microsphere (MS) with the particle size of 50 nm (MS-50) or 500 nm (MS-500) was characterized after intravenous administration to rats. A rapid elimination from systemic circulation was observed for both MSs. Tissue distribution of MS-50 and MS-500 at 1 h after intravenous injection indicated that both MSs were exclusively distributed to liver and that small but significant amounts of MS-50 and MS-500 were also distributed to lung and spleen, respectively. To investigate the intrahepatic distribution of MS, liver was separated into liver parenchymal cells (PC) and non-parenchymal cells (NPC) at 1 or 6 h after intravenous administration. The contribution of each cell fraction was dependent on both the size of MS and the time after administration. Furthermore, by separating the NPC into endothelial cells and Kupffer cells using a centrifugal elutriation method, their contribution was also evaluated. For both MSs, Kupffer cells were recognized to be mostly responsible for the hepatic uptake, although a significant amount of MS-50 (about 28% of total uptake) was taken up by PC. On the other hand, there was little contribution of PC (about 5%) to the hepatic uptake of MS-500. The endothelial cells were contributed larger to the uptake of MS-500 (about 24%) than that of MS-50 (13%).

Co-localization of mitochondrial and double minute DNA in the nuclei of HL-60 cells but not normal cells

In an attempt to isolate genes located on double minute (Dmin) DNA in HL-60 cells, we prepared DNA probe from purified micronuclei. Micronucleation was induced in HL-60 cells by treatment with hydroxyurea. Screening of a cDNA library unexpectedly produced a number of clones containing mitochondrial DNA (mtDNA) sequences. Here, we show that amplified mtDNA sequences were localized in nuclei and micronuclei of HL-60 and COLO 320DM cells, but not in nuclei of WI-38 normal human fibroblasts or peripheral blood T-cells. To unequivocally demonstrate the presence of mtDNA inside of nuclei and micronuclei, we obtained tomographic fluorescence in situ hybridization (FISH) images of mtDNA by confocal microscopy of consecutive sections of paraformaldehyde (PFA)-fixed material. We also located mtDNA in nuclear buds and purified micronuclei. Dmin DNA and mtDNA were always located at similar sites. The mechanisms of nuclear retention of mtDNA and Dmin DNA and the resulting influence on tumorigenesis are discussed.

Surface phenotype analysis of CD16+ monocytes from leukapheresis collections for peripheral blood progenitors

In peripheral blood progenitor cell (PBPC) collections from patients with solid tumour or haematological malignancy, monocytes were separated into two subpopulations. The majority of monocytes expressed CD14 at a high density without CD16 antigen (the CD14+CD16- monocytes). The remaining monocytes co-expressed CD14 and CD16 (the CD14+CD16+ monocytes). These CD14+CD16+ monocytes amounted to 20.6 +/- 15.8%, while those in peripheral blood (PB) obtained from healthy volunteers were 7.3 +/- 3.1% (P < 0.05). When subdividing the CD14+CD16+ monocytes into CD14brightCD16dim and CD14dimCD16bright cells, both populations were found to be increased in PBPC collections. Since typical CD14+CD16+ monocytes are the CD14dimCD16bright population, we compared the additional surface antigens on CD14dimCD16bright monocytes with those of CD14+CD16- monocytes. In PBPC collections, the CD14dimCD16bright monocytes exhibited lower levels of CD11b, CD15, CD33 and CD38 expression and higher levels of CD4, CD11a, CD11c and MHC class II, and also revealed a higher percentage of CD4+ cells and a lower percentage of CD15+ cells and CD38+ cells, compared with the CD14+CD16- monocytes. When compared with the CD14dimCD16bright monocytes in PB, those in PBPC collections exhibited higher expression of CD4 and lower expression of CD11b, and also showed higher percentages of CD4+ cells and CD38+ cells and a lower percentage of CD11b+ cells. These results suggest that PBPC collections may be rich in the CD14+CD16+ monocytes in which the proportion of the immature population is increased. It is likely that these monocytes participate in the haematological and immune recovery after PBPC transplantation.

Detection of K-ras and p53 gene mutations in pancreatic juice for the diagnosis of intraductal papillary mucinous tumors

The aim of this study was to investigate mutations of the K-ras oncogene and the p53 tumor suppressor gene in pancreatic juice and to evaluate our method for the diagnosis of intraductal papillary mucinous tumors (IPMT). Pancreatic juice was collected endoscopically from 12 patients with IPMT who underwent surgical resection (eight carcinomas and four adenomas) and eight cases without evident pancreatic diseases. DNA was extracted and both genes were examined by polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing. In addition, surgically resected specimens were analyzed for both genes by the same methods, and p53 overexpression was investigated immunohistochemically. K-ras point mutations were detected in pancreatic juice from all 12 patients (100%) and p53 mutations were detected in five of 12 (42%). They were detected not only in carcinoma but also in adenoma and there was no difference between the mutations detected in pancreatic juice and surgical specimens. No mutations were found in any cases without pancreatic diseases. These findings suggest that alterations of K-ras and p53 gene are common events in the development of IPMT and that genetic analysis of them in pancreatic juice can be a useful tool for the clinical diagnosis of IPMT before surgery.

[Two cases of testicular infarction: the usefulness of enhanced MRI for preoperative diagnosis]

The differential diagnosis in acute scrotum, particularly torsion of spermatic cord and epididymitis, is sometimes difficult. An erroneous diagnosis may result in unnecessary and improper treatment. We report two cases of testicular infarction including torsion of spermatic cord, preoperatively diagnosed by enhanced magnetic resonance imaging (MRI). Case 1: A 16-year-old boy presented with a 3-day history of left scrotal swelling and left lower abdominal pain. He had fever and leukocytosis. Antibiotics for 2 days failed to relieve the symptoms. Enhanced MRI showed absence of blood flow in the left testis. Scrotal exploration revealed hemorrhage and necrosis in the left testis. Left orchiectomy and right orchiopexy were performed. Case 2: A 12-year-old boy visited with scrotal swelling and fever 30 hours after an acute onset of left scrotal pain. Enhanced MRI showed absence of blood flow in the left testis. Exploration revealed left necrotic testis with torsion of spermatic cord. Left orchiectomy and right orchiopexy were performed. Our two cases suggested that enhanced MRI, by which the intratesticular blood flow can be evaluated, may be useful for the diagnosis of testicular infarction.

[Multivariate analyses using quantitative method II of annoyance due to tinnitus]

Factors affecting annoyance due to tinnitus were analyzed using quantitative method II. Ninety-one patients with unilateral tinnitus of single kind were studied. Major factors affecting annoyance due to tinnitus were found to be subjective loudness of tinnitus, age, degree of hearing loss, tinnitus loudness level in dB HL, pitch matched frequency, puerility and impurity of tinnitus tonality, and subjective tinnitus pitch. Increased annoyance due to tinnitus was associated with an age of 30-49 years, a tinnitus loudness level between 25 and 49 dB HL, a tinnitus loudness level more than 15dB SL, impurity of tinnitus tonality, larger subjective loudness, and high-pitched tones above 4000Hz. Decreased annoyance due to tinnitus was related to the smaller subjective loudness, loudness level below 25dB HL, low-pitched tones below 250Hz, and purity of tinnitus tonality. Our results suggest that these factors are responsible for individual differences in annoyance caused by tinnitus.

Regulation of DNA-replication origins during cell-cycle progression

We have shown previously that chromosome VI of Saccharomyces cerevisiae contains nine origins of DNA replication that differ in initiation frequency and replicate sequentially during the S phase of the cell cycle. Here we show that there are links between activation of these multiple origins and regulation of S-phase progression. We study the effects of a DNA-damaging agent, methyl methane sulphonate (MMS), and of mutations in checkpoint genes such as rad53 on the activity of origins, measured by two-dimensional gel analysis, and on cell-cycle progression, measured by fluorescence-activated cell sorting. We find that when MMS slows down S-phase progression it also selectively blocks initiation from late origins. A rad53 mutation enhances late and/or inefficient origins and releases the initiation block by MMS. Mutation of rad53 also results in a late origin becoming early replicating. We conclude that rad53 regulates the timing of initiation of replication from late origins during normal cell growth and blocks initiation from late origins in MMS-treated cells. rad53 is, therefore, involved in the cell's surveillance of S-phase progression. We also find that orc2, which encodes subunit 2 of the origin-recognition complex, is involved in suppression of late origins.

[Urolithiasis associated with Crohn's disease: a case report]

We report a case of urolithiasis caused by surgical treatment for Crohn's disease. A 28-year-old woman was referred to our department for further examination of renal stones from the medical department in September, 1995. She suffered from Crohn's disease and had a history of jejuno-ileal resection because of perforation of the ileum in 1988. Radiographs revealed multiple bilateral renal stones, and the urine oxalate concentration was elevated. She was treated with extracorporeal shock wave lithotripsy and the administration of sodium bicarbonate and citrate, but these treatments did not prevent recurrence and enlargement of stones. Renal function was gradually worsened and we performed transurethral lithotomy and percutaneous nephrolithotripsy. The stones were mainly composed of oxalate calcium monohydrate. A renal biopsy was performed at the operation, showing deposition of crystals in almost all renal tubules. Diet therapy (low oxalate and low fat) and the administration of sodium bicarbonate and citrate were performed strictly and recurrence was not recognized 10 months after complete removal of the stones.

[The effect of cervical sympathectomy on the pituitary and pineal endocrine system]

It was reported previously that continuous exposure to light in male rats increased serum luteinizing hormone (LH) and bilateral cervical sympathectomy inhibited such a change. In the present report, to examine the effect of cervical sympathectomy on the pineal endocrine function, 30 male rats were assigned to five groups. The control (C) group and the light (L) group underwent sham sympathectomy as well as sham pinealectomy. The sympathectomy (S) group underwent sympathectomy and sham pinealectomy. The pinealectomy (P) group and pinealectomy-melatonine (PM) group underwent sympathectomy and pinealectomy. The C group was kept under a normal circadian rhythm for 10 days, and the other groups were kept under continuous exposure to light for the same period. The PM group received subcutaneously 10 mg.kg-1 of melatonine every day. Serum LH levels were measured 10 days following these experiments. With regard to serum LH levels, the differences among C group, L group, and S group were similar to those previously reported. It was higher in P group (2.53 +/- 0.40 ng.ml-1) than in S group (1.58 +/- 0.61 ng.ml-1), and lower in PM group (2.08 +/- 0.31 ng.ml-1) than in P group. In conclusion, it is suggested that the endocrine activity of melatonine from the pineal gland plays an important role in the appearance of the effect of cervical sympathectomy.

Fabrication of spatial walk-off polarizing film exhibiting a large split angle by oblique silicon deposition

A spatial walk-off polarizing film with a large split angle was fabricated by use of the oblique deposition method. The film is composed of slanted needlelike microcolumns of a-Si that are separated by resultant fine voids. The polarization-splitting characteristics of the film were clearly observed. The maximum split angle at a wavelength of 1.55 microm was as large as 20 degrees , more than three times greater than those of existing polarizers such as those constructed of rutile and calcite.

A 'neural' response with 3-ms latency evoked by loud sound in profoundly deaf patients

A large negative deflection with a latency of 3 ms was observed in the auditory brainstem response (ABR) waveforms of some patients with peripheral profound deafness. This deflection was termed the N3 potential. In this paper, we review patients with the N3 potential and discuss the characteristics of abnormal ABR waveforms. The origin of the N3 potential was also discussed, especially with respect to vestibular evoked potentials. In most of the patients, audiograms showed no response to the maximum output of an audiometer in the high-frequency range and a residual response in the low-frequency range. The N3 potentials were noted at intensities of 80 dB nHL or greater. As the stimulus intensity increased, the amplitude of the potential increased and the latency decreased. A high repetition rate (83.3/s) of the click stimulus influenced the latency and amplitude of the N3 potential. The potential was replicated on retest within less than a month, and had a consistent latency and amplitude over the scalp. The results indicate that the N3 potential is not an electrical artifact but a physiological neural response evoked by a loud sound. The N3 potential is most likely not an auditory evoked response from cochlear or a response from a semicircular canal, because it has a 3-ms latency, a sharp waveform, and is unassociated with vertigo. The results suggest that the N3 potential may be a saccular acoustic response.

Total respiratory system compliance after thoracoplasty

Recent attention has been directed towards the deleterious effects of the sequelae of pulmonary tuberculosis on respiratory function. Thus, a study was undertaken to find out to what extent the deformity of thorax after thoracoplasty increases the mechanical work of breathing. Compliance of the total respiratory system (Crs) was measured with a pressure-type body plethysmograph in nine post-thoracoplasty tuberculosis patients, 15 patients with pulmonary tuberculosis and three patients with pleural diseases. Mean Crs in nine post-thoracoplasty tuberculosis patients was 0.0861 cmH2O-1, and that in six patients with moderately advanced pulmonary tuberculosis was 0.0841 cmH2O-1. Mean Crs (0.1301 cmH2O-1) in nine patients with a minimum lesion of tuberculosis was not different from the reference Crs values reported to date by several authors. Crs was significantly correlated with vital capacity, but not with functional residual capacity. There was no difference in specific Crs between post-thoracoplasty tuberculosis patients and patients with moderately advanced pulmonary tuberculosis. Crs of patients with a pleural disease was smaller than Crs of patients with a minimal lesion of pulmonary tuberculosis. The deformity of thorax after thoracoplasty caused a decrease of Crs. However, ventilation is not as severely impaired as anticipated from the degree of thorax deformity on chest X-ray film, providing that movement of the diaphragm is unrestricted.

Relationship between platelet membrane lipid compositions and platelet aggregability in alcoholic liver disease

We studied the relationship between changes in platelet aggregability and platelet membrane lipid in alcoholic liver disease. The maximal rate of ADP-induced platelet aggregation was significantly increased in the alcoholic liver disease group than in the control group. No significant difference was observed in the maximal rate of collagen-induced platelet aggregation. However, a lag time required for the start of platelet aggregation was significantly shortened in the alcoholic liver disease group, indicating increased platelet aggregability. Results of the platelet aggregation test suggested that alcoholic liver disease patients have their platelet aggregation affected by the abnormality of prostaglandin metabolism. The alcoholic liver disease group was further divided into two subgroups: the hyperaggregation group and the unchanged aggregation group. Both free cholesterol and phospholipid in the platelet membrane were significantly increased in the alcoholic liver disease group. In phospholipid compositions, phosphatidylserine plus phosphatidylinositol were significantly decreased in the alcoholic liver disease group, whereas a significant decrease in phosphatidylserine plus phosphatidylinositol was observed in the hyperaggregation group of alcoholic liver disease. Analysis of fatty acid compositions of platelet membrane showed significantly decreased palmitic acid in the alcoholic group. There was no significant change of arachidonic acid, which directly affects platelet aggregation. Eicosapentaenoic acid significantly decreased in the alcoholic liver disease group, but there was no difference in docosahexaenoic acid. Meanwhile, the thrombogenic index, calculated from the fatty acids of platelet membrane, showed no difference between the alcoholic liver disease group and the control group. However, the thrombogenic index was significantly increased in the hyperaggregation group than in the unchanged aggregation group. These data suggested that platelet aggregation is affected by not only a change in arachidonic acid, but also changes in fatty acid compositions of the platelet membrane.

Expression of vascular endothelial growth factor correlates with tumor progression in gallbladder cancer

Angiogenesis must occur for malignant tumors to proliferate and vascular endothelial growth factor (VEGF) is now believed to be central to this process. Immunohistochemical staining for VEGF was performed on surgical resection specimens from 50 patients with gallbladder cancer. VEGF-positive rate was 38%. Comparison of clinicopathologic parameters between the groups with and without VEGF expression showed significant differences in tumor size, lymphatic invasion and disease stage. Survival rate was worse in the patients whose tumors demonstrated VEGF expression. It is suggested that VEGF is correlated with tumor progression and may be used as a prognostic indicator.

Prostaglandin E1 from the tip of an intraaortic balloon catheter for lower limb ischemia

A method to treat lower limb ischemia associated with the insertion of an intraaortic balloon catheter is herein reported. A low dose of prostaglandin E1 was administered into the descending aorta continuously from the tip of the intraaortic balloon catheter. Immediately after the administration of prostaglandin E1 in patients whose lower limbs were ischemic due to obstruction with the catheter, the peripheral circulation of the ischemic limbs recovered with minimal changes in the systemic arterial blood pressure. This method is simple and noninvasive and was found to induce a satisfactory effect.