Search PubMed⌕ Search

Biomedical subjects

R Sakakibara

Publications and source records attributed to R Sakakibara.

At least 73 records · Page 4Linked to original sources

Liposome oligomannose-coated with neoglycolipid, a new candidate for a safe adjuvant for induction of CD8+ cytotoxic T lymphocytes.

The cytotoxic T lymphocyte (CTL) response has recently been shown to play a role in protection against human immunodeficiency virus (HIV) and it is therefore thought that a vaccine against HIV must be able to elicit a CTL response. The development of a safe, effective adjuvant is very important because alum, the only adjuvant available for use in humans at present, can barely induce a response of this type. We demonstrate here that liposomes that contain an immunodominant peptide (15 amino acids) of the envelope glycoprotein gp120 of HIV-1 and that are coated with mannopentaose-dipalmitoylphosphatidylethanolamine conjugate induce a major histocompatibility complex class I-restricted CD8+ CTL response in mice with a single subcutaneous immunization, whereas non-coated liposomes do not. Since no damage to the skin at the injection site was caused by the liposomes, and since the oligomannose-coated liposomes consist of innocuous materials ubiquitously distributed throughout the human body, they may be highly suitable for use as a safe adjuvant in vaccines inducing a CTL response against HIV.

Adjuvants, Immunologic↗

Expression of human placental-type 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase in various cells and cell lines.

The expression of the human placental-type 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (HP2K) in various human cells and cell lines was investigated at the levels of transcription and translation. Analyses by both Northern blotting and a reverse transcription-polymerase chain reaction (RT-PCR) showed that BeWo, U-937, SupT1, H9, HeLa, HepG2, and human mononuclear cells, as well as human placental chorionic cells, expressed HP2K mRNA. All the nucleotide sequences of RT-PCR products from these cell lines were identical to that of HP2K. The expression of HP2K protein was determined by Western blot analysis of fractions from POROS-HQ column chromatography of the cell extracts from U-937 cells, which was used as an example of HP2K-mRNA positive cell lines. As with the 6-phosphofructo-2-kinase activity of HP2K, the activity of 6-phosphofructo-2-kinase in extracts of U-937 cells was not inhibited by glycerol 3-phosphate, a known 6-phosphofructo-2-kinase inhibitor of liver- and testis-type isozymes. These results strongly suggested that various cell lines, in particular U-937 cells, express functional HP2K enzyme. Furthermore, 6-phosphofructo-2-kinase in U-937 cells was found to be activated by treatments with isoproterenol and phorbol 12-myristate 13-acetate, indicating regulation of 6-phosphofructo-2-kinase activity in U-937 cells by protein kinases A and C.

Blotting, Northern↗

Micturitional disturbance in a patient with adrenomyeloneuropathy (AMN).

We report a case of adrenomyeloneuropathy (AMN) in which serial urodynamic studies showed neurogenic bladder dysfunction. The patient was in good health until the age of 12, when he began to lose his hair. At age 25 he started to have urinary urgency, difficulty in voiding, occasional fecal incontinence, erectile impotence, and progressive gait disturbance. In his first admission to our hospital age 31, he was intelligent but childish. He showed diffuse baldness, spastic paraparesis, and disturbed vibratory sensation. Serum cortisol response to corticotropin (ACTH) was low and serum levels of very long chain fatty acids were increased. Nerve conduction studies and sural nerve biopsy showed the presence of peripheral neuropathy. These findings confirmed the diagnosis of AMN. The first urodynamic study showed residual urine volume of 50 ml, impaired bladder sensation, and detrusor hyperreflexia. At age 38 he needed diapers because he became apathetic and demented, and could no longer stand by himself. MRI disclosed high signal intensities in the bilateral cerebral white matter. The second urodynamic study showed residual urine volume of 200 ml and decreased bladder capacity with marked detrusor hyperreflexia. Demyelinating lesions of the peripheral nerve and white matter of the spinal cord and the cerebrum may be mainly responsible for the micturitional disturbance in our patient with AMN.

Adrenoleukodystrophy↗

Urinary retention due to herpes virus infections.

Urinary retention is uncommon in patients with herpes zoster and anogenital herpes simplex. Seven patients (four men, three women) with a mean age of 68.1 years (range, 35-84) with urinary retention due to herpes zoster (n = 6) or anogenital herpes simplex (n = 1) were studied. Six patients had unilateral skin eruption in the saddle area (S2-4 dermatome) and one patient with herpes zoster had a skin lesion in the L4-5 dermatome. All patients had detrusor areflexia without bladder sensation, and two of them had inactive external sphincter on electromyography at presentation. Clean intermittent catheterization was performed, and voiding function was recovered in 4-6 weeks (average, 5.4) in all patients. Urodynamic study was repeated after recovery of micturition in three patients, and they returned to normal on cystometrography and external sphincter electromyography. Acute urinary retention associated with anogenital herpes infection has been thought to occur when the meninges or sacral spinal ganglia were involved, and, in conclusion, this condition may be considered to be reversible.

Acyclovir↗

Micturitional disturbance in herpetic brainstem encephalitis; contribution of the pontine micturition centre.

Micturitional disturbance is rarely mentioned in human herpetic brainstem encephalitis although the pontine tegmentum, called the pontine micturition centre, seems to regulate the lower urinary tract in experimental animals. The case of a 45 year old man, who developed subacute coma and hiccup-like dysrhythmic breathing, and needed assisted ventilation is reported. Examination of CSF showed mononuclear pleocytosis and antibody against herpes simplex virus type 1, but the opening pressure was 90 cm H2O. Brain CT showed brain swelling, predominantly in the posterior fossa, and bilateral subdural effusion. Herpetic brainstem encephalitis was diagnosed, and he received 900 mg/day vidarabine. On regaining consciousness, he had left trochlear nerve palsy, left corectopia, ageusia, and urinary retention. Brain MRI showed right side dominant, bilateral pontine segmental lesions extending slightly to the midbrain and medulla. After two weeks he was able to urinate but showed nocturnal urinary frequency, urinary incontinence, and voiding difficulty. Urodynamic studies showed a residual urine volume of 350 ml and detrusor hyporeflexia on voiding. Micturitional disturbance gradually disappeared together with the neurological signs. The bilateral pontine tegmental lesions in this patient are similar to those in previous findings on brainstem strokes, evidence of the presence of a pontine micturition centre in humans.

Antibodies, Viral↗

Stress induced urinary incontinence in patients with spinocerebellar degeneration.

OBJECTIVES: To examine the pathophysiology of "stress induced urinary incontinence" (urinary incontinence evoked by abdominal straining) in patients with spinocerebellar degeneration. METHODS: Micturitional symptoms of 184 patients with spinocerebellar degeneration who were admitted to hospital were studied repeatedly. Urodynamic studies were made in symptomatic patients, and consisted of uroflowmetry, measurement of residual urine, urethral pressure profilometry, medium fill water cystometry, and external sphincter EMG. RESULTS: Twenty nine (15.8%) patients with spinocerebellar degeneration showed stress induced urinary incontinence. Twenty of the 29 patients had detrusor overactivity, low compliance detrusor, or residual urine, resembling urgency and overflow types of incontinence (complicated form). The other nine had none of these findings (pure form), but showed decreased maximum urethral closure pressure in four, absence of bulbocavernosus reflex in two, absence of voluntary sphincter contraction in one, incompetent urinary storage even at the first sensation in two, and high amplitude and polyphasic neurogenic changes in three of five patients studied, indicative of neurogenic sphincter dysfunction. CONCLUSIONS: Stress induced urinary incontinence in spinocerebellar degeneration had various underlying mechanisms. Some of the patients only showed evidence of pudendal denervation, which can cause external sphincter weakness and may reflect lesions of the sacral Onuf's nucleus and the pudendal nerve. Urodynamic studies are necessary to evaluate stress induced urinary incontinence in patients with spinocerebellar degeneration, to prescribe appropriate therapies.

Adolescent↗

Detrusor overactivity and penile erection in patients with lower lumbar spine lesions.

OBJECTIVES: To investigate urodynamically detrusor overactivity and evaluate surgical outcome in patients with lower lumbar spine lesions. METHODS: Eighty patients with spine lesions below the third lumbar spine including 31 patients with intervertebral disc prolapse (IDP) (mean age: 38.2 years) and 49 patients with spinal canal stenosis (SCS) (mean age: 56.7 years) were studied. Urinary symptoms and urodynamic data were recorded before and after orthopedic surgery. RESULTS: Detrusor overactivity was noted in 17 patients: 3 IDP patients (10%) and 14 SCS patients (29%). Of these 17 patients (9 males and 8 females), 14 (82%) had voiding symptoms and 15 (88%) had storage symptoms. One patient was asymptomatic. Intermittent claudication was noted in 14 patients: 8 had urgency, 11 urge incontinence and 4 male patients showed erection on walking. Of 10 patients followed up after surgery, detrusor overactivity disappeared in 5 patients, improved in 1 patient and remained unchanged in 4 patients. CONCLUSIONS: Detrusor overactivity was found in lower lumbar spine lesions. This phenomenon seemed to be caused by the irritation of sacral roots, especially on walking.

Adolescent↗

Micturitional disturbance in patients with chronic inflammatory demyelinating polyneuropathy.

Eight of 32 patients (25%) with chronic inflammatory demyelinating polyneuropathy (CIDP) had micturitional disturbance, which consisted of voiding difficulty (n = 4), urgency (n = 4), or urgency incontinence (n = 1). Urodynamic studies on four symptomatic patients showed disturbed bladder sensation in two, bladder areflexia in one, and neurogenic changes of the external sphincter in one, indicative of peripheral parasympathetic and somatic nerve dysfunctions. Cystometry also showed detrusor overactivity in two patients but no evidence of CNS involvement, evidence that bladder overactivity occurs by probable pelvic nerve irritation.

Adolescent↗

Efficiency of targeted gene delivery of ligand-poly-L-lysine hybrids with different crosslinks.

Hybrids of a ligand protein crosslinked to a DNA binding protein have been developed as gene delivery vehicles mediated by receptors. To identify the effect of the crosslinks between the ligand and DNA binding protein on gene expression caused by an internalized hybrid-DNA complex, we prepared two kinds of transferrin-poly-L-lysine (TF-PL) hybrids: one was crosslinked by probably cleavable disulfide bonds (TF-ss-PL) and the other was linked by a probably uncleavable Schiff's base (TF-Schiff-PL). The binding affinity of the hybrids to HeLa cells was not different. However, the expression of a reporter gene (for luciferase) bound to these hybrids in HeLa cells transfected with TF-Schiff-PL was greater than that of TF-ss-PL.

Asialoglycoproteins↗

A common phosphorylation site for cyclic AMP-dependent protein kinase and protein kinase C in human placental 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase.

Human placental 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (HP2K) was phosphorylated by incubation with [gamma-32P]MgATP and cyclic AMP-dependent protein kinase (PKA) or protein kinase C (PKC). Approximately 0.8 mol of phosphate per mol subunit of HP2K was incorporated by either PKA or PKC. However, with additional incubation with PKA following incubation with PKC or vice versa, no additional phosphate was incorporated into the HP2K. The phosphorylation sites for the two protein kinases were identified by peptide mapping and microsequencing following digestion of phosphorylated-HP2K with clostripain. Evidence is also suggested for a common phosphorylation site (Ser-460) for PKA and PKC.

Amino Acid Sequence↗

Effect of replacement of the amino and the carboxyl termini of rat testis fructose 6-phosphate, 2-kinase:fructose 2,6-bisphosphatase with those of the liver and heart isozymes.

Fru 6-P,2-kinase:Fru 2,6-Pase is a bifunctional enzyme, consisting of highly conserved catalytic domains and variable regulatory domains. The regulatory domains reside in either the N- or the C-terminus, depending upon the isozyme. The rat testis enzyme (RT2K) lacks the regulatory domain, but the rat liver and the bovine heart enzymes contain phosphorylation site(s) in the N- and the C-termini, respectively. In order to determine whether the regulatory domains can be swapped, we have constructed mutant enzymes in which the N- or the C-terminal tail of the testis enzyme was replaced with that of either the liver or the heart enzyme. The substitution with the N-terminus of the liver enzyme (RLN-RT2K) resulted in a small change in the kinetic properties of Fru 6-P,2-kinase, but that with the heart enzyme increased the KFru 6-P 18-fold without affecting the Vmax. The substitution with the C-terminus of the heart enzyme had little effect. The phosphorylation of RLN-RT2K increased KFru 6-P fivefold as in the liver enzyme but did not affect the Fru 2,6-Pase, unlike the liver enzyme. All these mutant enzymes were more thermally labile than the wild type testis enzyme. RLN-RT2K was more sensitive to the denaturant. These results suggest that the N-terminus of the liver enzyme could interact with the kinase domain of the testis enzyme, regulating the kinase activity but was unable to affect the phosphatase domain. These differences could be explained by the large differences in net charges of the terminal tails.

Allosteric Regulation↗

The nature of detrusor bladder neck dyssynergia in non-neurogenic bladder dysfunction.

There have been two major opinions on the pathology or nature of the bladder neck contracture. One is an organic fibrosis, and the other is an accentuated sympathetic nervous function, or detrusor bladder neck dyssynergia. The existence of active detrusor bladder neck dyssynergia in neurogenic bladder was reported in a urodynamical manner using microtip transducer catheters. However, it has not been confirmed whether or not detrusor bladder neck dyssynergia is responsible for bladder neck contracture in patient without neurogenic bladder. The present study was designed to determine by means of video urodynamic study whether or not bladder neck contracture would be of the same nature as detrusor bladder neck dyssynergia in non-neurogenic bladder subjects. The study included 32 male subjects of 16-84 years old (average 52.3): 17 bladder neck contracture subjects including 7 subjects associated with minimum complications (4 with trapped benign prostatic hyperplasia and 3 with incomplete neurological lesion) and 15 non-bladder neck contracture subjects (10 healthy volunteers, 2 chronic prostatitis, 3 prostatodynia). A 5-microtip transducer catheter was used to measure the pressure in the bladder and at the bladder neck, the external urethral sphincter and the bulbous urethra during voiding. Proper localization of the transducers was done with an image intensifier. Bladder outlet obstruction localized at the bladder neck (diameters smaller than 0.75 cm) on voiding cystourethrogram was defined as bladder neck contracture. Detrusor bladder neck dyssynergia was defined where pressures were higher at the level of bladder neck than in the bladder during detrusor contraction. An alpha-blocker, terazosin hydrochloride (0.5 mg, b.i.d., two weeks), was orally administered to subjects judged to have detrusor bladder neck dyssynergia by the above methods for the purpose of confirming whether detrusor bladder neck dyssynergia was really due to accentuated sympathetic nervous function. Detrusor bladder neck dyssynergia was found in seven cases with bladder neck contracture: 6 cases with bladder neck contracture with minimum complications and only 1 case with bladder neck contracture without complications (p < 0.01). Detrusor bladder neck dyssynergia was found at the beginning and ending of micturition, but not at maximum flow. In six cases with detrusor bladder neck dyssynergia, the condition disappeared after terazosin. In conclusion, detrusor bladder neck dyssynergia was not thought to be a major factor of voiding dysfunction in bladder neck contracture in non-neurogenic bladder. In the presence of sympathetic hyperactivity or in cases with increased number of alphareceptors, detrusor bladder neck dyssynergia occurs, being predominantly noted in trapped benign prostatic hyperplasia and neurological disorder patients.

Adolescent↗

Micturitional disturbance in Wernicke's encephalopathy.

A 24-year-old pregnant woman started to have hyperemesis gravidarum 6 weeks before admission. Four weeks later she had vertigo, diplopia, staggering gait, mild dyspnea, dysphagia, and incontinence of urine. On admission she presented with ophthalmoplegia, ptosis, ataxia, decreased tendon reflex, and memory disturbance. Brain magnetic resonance imaging revealed abnormal intensities in medial thalamic-hypothalamic regions and the periaqueductal area, and she was diagnosed with Wernicke's encephalopathy. Urodynamic studies revealed decreased bladder volume and detrusor hyperreflexia. Six weeks after the administration of 100 mg/day of thiamine, urge incontinence gradually recovered, together with neurological signs. Lesions of the medial thalamic-hypothalamic area and the periaqueductal gray matter seemed to be mainly responsible for micturitional disturbance in our patient with Wernicke's encephalopathy.

Adult↗

Urodynamic and cardiovascular measurements in patients with micturition syncope.

We describe the findings of urodynamic studies, together with blood pressure and heart rate monitoring, in five patients with micturition syncope. All patients had almost normal storage and evacuation function and no evidence of prostate hypertrophy. Conventional head-up tilt testing with an empty urinary bladder caused no change in arterial blood pressure, but a moderate increase in heart rate. Urinary bladder filling caused minimal increases of the arterial pressure and heart rate. The sitting posture with a distended bladder caused mild orthostatic hypotension. Urinary bladder evacuation caused a fall in arterial pressure with a decrease in heart rate. These responses were similar to those described in vasovagal syncope. The central mechanism for the initiation of urinary evacuation, or sensory input from the lower urinary tract, may trigger micturition syncope.

Adult↗

Orthostatic hypotension in a case with multiple sclerosis.

A 37-year-old woman with a 5-year history of multiple sclerosis is reported. She began having recurrent syncope even in the sitting position; other neurological features included hiccup, faciooro-lingual flushing and clumsiness of the hands. She had alternating Horner's syndrome, mild hypoalgesia of the right face, exaggerated deep tendon reflexes of the upper extremities, decreased deep sensation and ataxia of the upper extremities, and incomplete transverse myelopathy with a T4 sensory level. Head-up tilt testing confirmed orthostatic hypotension with relative preservation of the heart rate increase. Magnetic resonance imaging indicated abnormal intensities in the paramedian tegmentum and base of the medulla, which may have been additionally responsible for orthostatic hypotension. Steroid pulse therapy and L-threo-3,4-dihydroxyphenylserine caused regression of brainstem signs and reduced syncopal attacks.

Adult↗

Pelvic floor electrical stimulation in the treatment of stress incontinence: an investigational study and a placebo controlled double-blind trial.

PURPOSE: We designed an investigational study and a placebo controlled, double-blind study to evaluate the usefulness of electrical pelvic stimulation in stress incontinence. MATERIALS AND METHODS: We studied 44 patients with stress incontinence (six men and 38 women, age 63 +/- 13), including 9 patients in the investigational study and 35 in the double-blind study. We used 50 Hz. square waves of 1 ms. pulse duration for stimulation. A vaginal electrode was used in women and an anal electrode in men. Urethral pressure profile before, during and after 15-minute stimulation was measured in the investigational study. In the double-blind trial an active device and a dummy device were used, and efficacy was judged from patient impressions, records in frequency/volume chart, results of 1-hour pad test and urodynamic parameters after 4-week treatment. RESULTS: In the investigational study maximum urethral closure pressure (mean plus or minus standard deviation) before, during and after stimulation was 44.4 +/- 17.5, 64.5 +/- 28.8 and 46.8 +/- 25.6 cm. water, respectively. This parameter significantly increased (p = 0.0275) during stimulation. In the double-blind trial patient impressions were good in 60% of the active device group and 8% of the dummy device group (p = 0.0051). For the pad test significant improvement was noted in the active device group (p = 0.0100). Cure rate was 45% in the active device group and 7.7% in the dummy device group. There were significantly more cured or improved patients for frequency of leakage (p = 0.0196) and pad test (p = 0.0100). CONCLUSIONS: Electrical stimulation is effective for the treatment of stress incontinence.

Aged↗

Chronic intractable headache in a patient with Marfan's syndrome.

A 30-year-old woman with Marfan's syndrome had chronic intractable headaches and spontaneous intracranial hypotension. The pain was concentrated over the occipitonuchal region, had elements of both migraine and tension headache, and was often aggravated by postural change. Myelography showed multiple, large, lumbosacral arachnoid diverticula. Radioisotope cisternography revealed a halolike accumulation in the lumbosacral region and rapid uptake of isotope in the urinary bladder, indicating cerebrospinal fluid leakage. Epidural blood patching brought immediate relief from the positional headaches. We concluded that patients with Marfan's syndrome and undifferentiated chronic headaches should be radiologically evaluated for spinal meningeal defects.

Adult↗