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Biomedical subjects

K Onishi

Publications and source records attributed to K Onishi.

At least 19 recordsLinked to original sources
PubMed2005

HLA-haploidentical nonmyeloablative stem cell transplantation: induction to tolerance without passing through mixed chimaerism.

There are few reports of unmanipulated HLA-haploidentical nonmyeloablative stem cell transplantation (NST) using only pharmacological acute graft-vs.-host disease (GVHD) prophylaxis. We present here a successful case of unmanipulated HLA-haploidentical NST for mediastinal large B cell lymphoma that was resistant to autologous peripheral blood stem cell transplantation (PBSCT). The conditioning regimen consisted of fludarabine, busulfan and rabbit anti-T-lymphocyte globulin (ATG) in addition to rituximab. GVHD prophylaxis was performed using tacrolimus and methylprednisolone 1 mg/kg. The patient had rapid engraftment, with 100% donor chimaerism in the lineages of both T cells and granulocytes on day +12, but developed no GVHD clinically. The patient is still in complete remission past day +1020, with no sign of chronic GVHD without receiving immunosuppressive agents. HLA-haploidentical NST may be performed without utilizing mixed chimaerism.

Adult↗
PubMed2002

Circadian rhythm of blood pressure is transformed from a dipper to a non-dipper pattern in shift workers with hypertension.

Shift workers make great use of health care services because they are associated with increased cardiovascular morbidity and mortality. Whether the circadian rhythm of blood pressure rapidly adapts to shift work is controversial. It is unknown if shift work has adverse effects on blood pressure in patients with hypertension. To evaluate the effects of shift work, we examined 12 male shift workers with untreated hypertension aged 53.6 +/- 2.5 years. Twenty-four hour ambulatory blood pressure monitoring was performed three times as follows: the last day of a 4-day period of day shifts (09.00 to 21.00), the first day of a 4-day period of night shifts (21.00 to 09.00), and the fourth day of night shifts (21.00 to 09.00). Blood pressure at night-time dropped significantly in the day-shift workers, showing a dipper pattern. Average differences in blood pressure in the sleep-wake cycle were decreased by 8.5% at the beginning of night shift work showing a non-dipper pattern. After 4 days the pattern was completely reversed to a dipper pattern. The results indicate that the circadian blood pressure pattern is changed from a dipper to a non-dipper pattern on the first day of the night shift and reverses to a dipper pattern within a few days. We suggest that night shift work may have unfavourable effects on blood pressure in patients with hypertension.

Blood Pressure↗
PubMed2001

Effects of therapeutic doses of human atrial natriuretic peptide on load and myocardial performance in patients with congestive heart failure.

The benefits of atrial natriuretic peptide (ANP) in patients with congestive heart failure (CHF) have been demonstrated. However, the myocardial actions of ANP remain unclear. Using relatively load-insensitive left ventricular pressure-volume analysis, the myocardial and load-altering actions of ANP in patients with moderate CHF were studied. After obtaining steady-state data using micromanometers and conductance catheters, ANP was infused in 9 patients with CHF at 0.01 and 0.1 microg/kg/min for 30 minutes, respectively. Hemodynamic variables, plasma ANP, and cyclic guanosine monophosphate (cGMP) levels were determined before and 30 minutes after each ANP infusion. ANP at 0.01 microg/kg/min increased plasma ANP and cGMP levels from 73 +/- 34 to 139 +/- 34 pg/ml and from 4 +/- 1 to 8 +/- 2 pmol/ml, respectively. ANP infusion caused a significant decrease in end-systolic pressure without any changes in heart rate. End-diastolic pressure was significantly decreased but there was no significant change in left ventricular end-diastolic volume. The time constant for isovolumetric relaxation was decreased. ANP infusion at 0.1microg/kg/min caused further decreases in end-systolic pressure, end-diastolic pressure and volume, and the time constant for isovolumetric relaxation (p <0.05) without any changes in heart rate. The slope of the end-systolic pressure-volume relation was increased from 1.3 +/- 0.2 to 1.6 +/- 0.3 mm Hg/ml (p <0.05), indicating increased contractility. Plasma ANP and cGMP levels were increased to 422 +/- 44 pg/ml and 16 +/- 3 pmol/ml, respectively. Thus, ANP infusion increased cGMP generation, decreased afterload and preload, and improved left ventricular systolic and diastolic function.

Atrial Natriuretic Factor↗
PubMed2001

Upregulation of functional beta(3)-adrenergic receptor in the failing canine myocardium.

Altered expression and functional responses to cardiac beta(3)-adrenergic receptors (ARs) may contribute to progressive cardiac dysfunction in heart failure (CHF). We compared myocyte beta(3)-AR mRNA and protein levels and myocyte contractile, [Ca(2+)](i) transient, and Ca(2+) current (I(Ca,L)) responses to BRL-37344 (BRL, 10(-8) mol/L), a selective beta(3)-AR agonist, in 9 instrumented dogs before and after pacing-induced CHF. Myocytes were isolated from left ventricular myocardium biopsy tissues. Using reverse transcription-polymerase chain reaction, we detected beta(3)-AR mRNA from myocyte total RNA in each animal. Using a cloned canine beta(3)-AR cDNA probe and myocyte poly A(+) RNA, we detected a single band about 3.4 kb in normal and CHF myocytes. beta(3)-AR protein was detected by Western blot. beta(3)-AR mRNA and protein levels were significantly greater in CHF myocytes than in normal myocytes. Importantly, these changes were associated with enhanced beta(3)-AR-mediated negative modulation on myocyte contractile response and [Ca(2+)](i) regulation. Compared with normal myocytes, CHF myocytes had much greater decreases in the velocity of shortening and relengthening with BRL accompanied by larger reductions in the peak systolic [Ca(2+)](i) transient and I(Ca,L). These responses were not modified by pretreating myocytes with metoprolol (a beta(1)-AR antagonist) or nadolol (a beta(1)- and beta(2)-AR antagonist), but were nearly prevented by bupranolol or L-748,337 (beta(3)-AR antagonists). We conclude that in dogs with pacing-induced CHF, beta(3)-AR gene expression and protein levels are upregulated, and the functional response to beta(3)-AR stimulation is increased. This may contribute to progression of cardiac dysfunction in CHF.

Adrenergic beta-1 Receptor Antagonists↗
PubMed2001

Correction of pectus excavatum using a sternal elevator: preliminary report.

Operative procedures to correct the deformity caused by pectus excavatum are generally based on either sternal elevation or turnover. In either case, the operation is highly invasive. By considering the softness of the costal cartilages in early childhood, we have developed an endoscopically assisted procedure that applies external traction continuously in order to elevate the depressed sternum and costal cartilages. Since August 1993, we have performed this operation in 11 patients with pectus excavatum who ranged in age from 3 years 1 month to 28 years. The traction screws came loose spontaneously in two early cases. Augmentation transfer of a latissimus dorsi muscle flap and dermal fat grafting were subsequently performed in these two patients, respectively. We achieved an excellent cosmetic outcome in the other nine patients, with results similar to those achieved with the conventional operation. Our technique is a two-stage procedure and the patient is limited in performing daily activities while wearing the traction device. Despite this drawback it can achieve permanent correction of the deformity. Accordingly, this method should be considered when pectus excavatum is corrected surgically, particularly in infants and young children.

Adolescent↗
PubMed2001

Sacral adipofascial turn-over flap for the excisional defect of pilonidal sinus.

The aim of pilonidal sinus surgery includes complete resection of the lesion and filling of the resultant soft-tissue defect by some means; this has a major influence on whether a lesion will occur after surgical treatment. The creation of a sacral adipofascial turn-over flap for the excisional defect has been performed in seven cases of pilonidal sinus since November of 1992. During the postoperative follow-up period, which ranged from 10 months to 7 years 11 months (mean duration, 5 years 2 months), partial dehiscence of the wound as a result of fatlysis was observed and treated conservatively in one case; however, primary healing was obtained in the other cases. No recurrence was seen in any of the seven cases. This procedure is not indicated in patients in whom wide skin resection is required because of the excessive tension associated with skin closure in such cases. However, the method is convenient, less invasive, and reliable, and therefore considered to be useful in the treatment of pilonidal sinus.

Adipose Tissue↗
PubMed2001

The role of ANG II and endothelin-1 in exercise-induced diastolic dysfunction in heart failure.

The diastolic dysfunction present at rest in congestive heart failure (CHF) is exacerbated during exercise (Ex). Increases in circulating ANG II and endothelin-1 (ET-1) during Ex may contribute to this response. We assessed the effect of Ex on circulating plasma levels of ANG II and ET-1 and left ventricular (LV) dynamics before and after pacing-induced CHF at rest and during Ex in nine conscious, instrumented dogs. Before CHF, there were modest increases in circulating levels of ANG II (but not ET-1) during Ex. LV diastolic performance was enhanced during Ex with decreases in the time constant of LV relaxation (tau), LV end-systolic volume (V(ES)), and LV minimum pressure with a downward shift of the LV early diastolic portion of the pressure-volume (P-V) loop. This produced an increase in peak LV filling rate without an increase in mean left atrial (LA) pressure. After CHF, the resting values of ANG II and ET-1 were elevated and increased to very high levels during Ex. After CHF, mean LA pressure, tau, and LV minimum pressure were elevated at rest and increased further during Ex. Treatment with L-754,142, a potent ET-1 antagonist, or losartan, an ANG II AT(1)-receptor blocker, decreased these abnormal Ex responses in CHF more effectively than an equally vasodilatory dose of sodium nitroprusside. Combined treatment with both ANG II- and ET-1-receptor blockers was more effective than either agent alone. We conclude that in CHF, circulating ANG II and ET-1 increase to very high levels during Ex and exacerbate the diastolic dysfunction present at rest.

Acetamides↗
PubMed2001

Multiple pulmonary emboli with pulmonary hypertension caused by effort thrombosis and effective balloon venoplasty of the subclavian vein.

A 36-year-old woman with effort thrombosis of the subclavian vein associated with multiple pulmonary emboli was successfully treated with local thrombolysis of the subclavian vein using a pulse-spray catheter and systemic anticoagulation. Balloon venoplasty of the residual stenosis of subclavian vein was carried out and in follow-up venography 6 months later, there was no restenosis, and the patient has been asymptomatic for 12 months. Pulmonary embolism is not a rare complication of upper extremity deep vein thrombosis and should be managed as aggressively as lower extremity deep vein thrombosis.

Adult↗
PubMed2001

Oxidation of bisphenol A and related compounds.

Bisphenol A was oxidized to monoquinone and bisquinone derivatives by Fremy's salt, a radical oxidant, though salcomine and alkali did not catalyze the oxidation by molecular oxygen. Bisphenol A, bisphenol B, and 3,4'-(1-methylethylidene)bisphenol were converted to their monoquinone derivatives in the presence of tyrosinase at 25 degrees C at pH 6.5, but not to the bisquinone derivatives under these conditions.

Benzhydryl Compounds↗
PubMed2001

Functional role of endogenous endothelin-1 in congestive heart failure treated with angiotensin II receptor antagonist.

Interactions between angiotensin (ANG) II and endothelin (ET)-1 receptor transduction pathways have been unclear in congestive heart failure (CHF). Therefore the objects of this study are, in CHF, whether production of ET-1 is modulated by ANG II and/or whether hemodynamic effects of endogenous ET-1 are modulated by ANG II. Twelve dogs were randomly assigned to two groups: untreated (n = 6) and treated with ANG II type 1 (AT1) receptor antagonist (TCV116, 1.5 mg/kg/d) (n = 6). After rapid ventricular pacing (240 bpm) for 4 weeks, plasma and cardiac ET-1 levels were compared between the two groups. Acute hemodynamic effects of a nonspecific ET(A&B) receptor antagonist, TAK044 (3 mg/kg plus 3 mg/kg/h i.v.) were examined in both groups by a conductance catheter and a micromanometer. After 4 weeks of pacing, plasma and cardiac tissue ET-1 levels were elevated in both groups to a similar degree. In the group treated with TCV116, TAK044 produced an increase in stroke volume and a decrease in total systemic resistance; heart rate was unchanged. The time constant of left ventricular (LV) relaxation was significantly decreased. The slope of LV end-systolic pressure-volume relation (E(ES)) was increased (p < 0.05), indicating an increased LV contractility. Thus endogenous ET-1 produces an arterial vasoconstriction and impairs LV contractility and relaxation in CHF with AT1 receptor antagonism. These hemodynamic responses to TAK044 in CHF treated with TCV116 were similar in untreated CHF. These results suggest that the production of ET-1 and the cardiac effects of endogenous ET-1 in CHF may be unaffected by ANG II acting through AT1 receptors.

Angiotensin Receptor Antagonists↗
PubMed2001

SMRT as a T3SF-binding protein.

p53-binding consensus-like sequence (T3SF) is located in the murine promoter region of tissue inhibitor of metalloproteinase 3 gene. To identify the genes that encode proteins that bind to T3SF DNA sequence, we screened a cDNA library using the Southwestern technique. The SMRT gene was cloned as one of the candidates. Addition of antibody against SMRT reduced the intensity of a band that is supposed to contain SMRT in electrophoresis mobility shift assay, although antibody against p53 had no effect. Ultraviolet (UV)-irradiation reduced the intensity of the SMRT complex whereas p53 complex was stabilized by UV-irradiation. These results suggest that SMRT may bind to T3SF sequence in p53-independent manner and dissociate from the sequence by UV irradiation.

Binding Sites↗
PubMed2000

The negative inotropic effect of beta3-adrenoceptor stimulation in the beating guinea pig heart.

Although beta3-adrenoceptors (ARs) have been extensively characterized in brown and white adipocytes, their actions in the beating heart are unclear. We examined the effects of a beta3-AR agonist, BRL37344, on cardiac function and calcium transients in Langendorff-perfused guinea pig hearts by simultaneously measuring left ventricular (LV) pressure and Ca2+-dependent indo-1 fluorescence. BRL37344 induced a dose-dependent negative inotropic effect at concentrations from 10(-11) to 10(-8) M. Maximally, LV developed pressure decreased to 80+/-2%, +dP/dt to 81+/-2%. and -dP/dt to 81+/-3% of their respective control values (p < 0.01). The amplitude of the Ca2+ transient also decreased (to 92+/-3% of the control level; p < 0.01). The BRL37344 dose-response curve was not altered by nadolol (10(-5) M), a potent beta1- and beta2-AR antagonist, but completely suppressed by bupranolol (10(-6) M), a potent beta1-, beta2- and beta3-AR antagonist. To assess the potential role of a nitric oxide synthase (NOS) pathway, we determined whether the NOS inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), modified the contractile response to BRL37344. L-NAME (10(-7) and 10(-4) M) attenuated the negative inotropic effects on LV developed pressure by 35 and 50%, suggesting that beta3-AR stimulation induces a negative inotropic effect on guinea pig hearts partly through a decrease in the Ca2+ transient and partly by the NOS pathway.

Adrenergic beta-Agonists↗
PubMed2000

Chiari malformation and syringomyelia in monozygotic twins: birth injury as a possible cause of syringomyelia--case report.

A 26-year-old female, the elder of monozygotic twins, presented with slow progressive numbness and pain in her left arm. Magnetic resonance (MR) imaging showed syringomyelia with Chiari malformation. The patient's birth had been difficult with prolonged delivery time, breech delivery, and neonatal asphyxia. MR imaging of the patient's twin sister showed mild tonsillar ectopia, but absence of syringomyelia. This younger sister was born without problems. The patient underwent syringosubarachnoid shunt at the C5-6 level. The syrinx was collapsed promptly, and her symptoms disappeared. This case of syringomyelia with Chiari malformation in one of twins suggests that birth injury is likely to be a cause of the pathogenesis of syringomyelia.

Adult↗
PubMed2000

Repertoire selection by pre-B-cell receptors and B-cell receptors, and genetic control of B-cell development from immature to mature B cells.

During B-cell development the surrogate light (SL) chain is selectively expressed in progenitor and precursor B cells during the developmental stages of D(H) to J(H) and V(H) to D(H)J(H) rearrangements. Approximately half of all muH chains produced by these rearrangements cannot pair with SL chains and cannot form a pre-B-cell receptor (pre-BCR). A spectrum of affinities between VpreB and individual V(H) domains generates preB cells with pre-BCR of different fitness which, in turn, determines the extent of the pre-B II-cell proliferation and the fidelity of allelic exclusion of the H chain locus. Once pre-BCR is expressed, SL chain expression is turned off. As pre-B II cells proliferate, SL is diluted out, thus limiting pre-BCR formation. As a consequence, pre-B II cells stop proliferating, become small and resting and begin to rearrange the L chain loci. Multiple rearrangements of the kappaL chain alleles are often detected in wild-type small pre-B II cells. Around 20% of the muH chain-expressing small pre-B II cells also express L chains but do not display the Ig on the surface. Hence, it is likely that not all L chains originally generated in resting pre-B II cells can pair with the muH chain previously present in that cell. The best fitting ones are selected preferentially to generate sIg+ B cells. Furthermore, the transition of immature B cells from the bone marrow to spleen and their development to mature cells appear as two separate steps controlled by different genes.

Alleles↗