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Biomedical subjects

T Kato

Publications and source records attributed to T Kato.

At least 127 records · Page 7Linked to original sources

Bacterial infections after intestine and multivisceral transplantation.

BACKGROUND: The frequency of bacterial infections (BI) in intestinal transplant (IT) patients is high with sepsis being the leading cause of death after this procedure. We herein report our experience with major BI to ascertain the incidence, microbiological and clinical factors, risk factors and outcome. MATERIALS AND METHODS: 124 patients (72 children and 52 adults) received 135 grafts: namely, 39 isolated intestine, 33 liver-intestine and 63 multivisceral. Only major BI were considered, namely, those associated with serious morbidity/mortality requiring specific therapy. Patient data were retrieved from computerized databases, flow-charts, and medical records. RESULTS: 92.7% patients showed BI. There were 327 episodes, representing 2.6 episodes/patient (2.8/patients with infection): 193 episodes of bacteremia (1.7/patient with BI) including 29.5% due to catheter related sepsis, 16.5% from abdominal source, 5.7% from respiratory origin and 4.1% from the wound. The organ locations includes 46 respiratory infections, 33 intraabdominal abscesses or infected fluid collections, 8 diffuse peritonitis, 34 wound infections and other miscellaneous sites: empyema, soft tissue infections, cholangitis em leader etc. Median time of infection was nine days after surgery (mean 22+/-3 days), with 67.7% patients having at least one BI before the end of the first month. Infection was present in 76.2% of the 63 deceased patients. An infectious episode during month 1, a clinically manifest abdominal infection and a positive intraabdominal culture had negative impacts on patient survival. CONCLUSIONS: BI are common and early complications after IT. The high rate of bacteremia, line sepsis and abdominal and respiratory infections reflect the recipient's condition, with chronic deterioration superimposed with the effects of prolonged abdominal visceral surgery.

Adult↗

Intestinal transplantation: advances in immunosuppression and surgical techniques.

Campath-1H is being used as induction immunosuppression for intestinal/multivisceral transplantation. Patient and graft survival in this preliminary experience is similar to previous studies but there has been a significant decrease in the incidence and severity of acute rejections without increase of opportunistic infections. Collage of the abdominal wall (transplantation of a composite graft of the abdominal wall) can provide biologic coverage of the newly transplanted abdominal organs if necessary. Partial abdominal exenteration, ex vivo resection, and intestinal autotransplantation may be useful in removing otherwise unresectable lesions of the root of the mesentery.

Graft Rejection↗

A metal dispersed sol-gel biocomposite amperometric glucose biosensor.

A new glucose biosensor has been fabricated by immobilizing glucose oxidase into a copper dispersed sol-gel derived ceramic-graphite composite. The copper in the biocomposite offers excellent electrocatalytic activity towards the reduction (at -0.2 V) as well as oxidation (at +0.45 V) of hydrogen peroxide liberated in the enzymatic reaction enabling sensitive and selective determination of glucose. A linear response to glucose in the concentration range between 2.7 x 10(-5) to 4.0 x 10(-3) M with a correlation coefficient of 0.9987 and 4.0 x 10(-5) to 5.6 x 10(-3) M with a correlation coefficient of 0.9989 were observed with the electrocatalytic reduction and oxidation, respectively. Ascorbic acid and uric acid did not interfere with the glucose measurement during catalytic reduction at -0.2 V, a Nafion membrane was used to eliminate these interferences during the electrocatalytic oxidation at +0.45 V. The combination of copper catalysis and the promising feature of sol-gel biocomposite favor the sensitive and selective determination of glucose with improved analytical capabilities.

Biosensing Techniques↗

A case of inflammatory demyelinating polyradiculoneuropathy associated with T-cell lymphoma.

Malignant lymphoma may present prominent peripheral nervous system disorders with variable etiologies. We describe a patient who presented with chronic relapsing polyradiculoneuropathy accompanied by right facial nerve palsy. Gadolinium enhancement of the right facial nerve and cervical spinal roots was noted on magnetic resonance imaging (MRI). Sural nerve biopsy specimens showed mononuclear cell infiltration around the vessels in the epineurium. Histopathological and immunohistochemical investigations of sural nerve specimens revealed perivascular infiltration of lymphocytes with T-cell dominancy. No apparent direct invasion of lymphoma cells was seen. The results of nerve conduction studies, sural nerve biopsy and cerebrospinal fluid examination were suggestive of immune-mediated inflammatory demyelinating neuropathy. The chronic and relapsing fashion and unique radiological findings in our patient expand on the previously reported features of peripheral neuropathy associated with peripheral T-cell lymphoma.

Biopsy↗

Small cell carcinoma of the esophagus; clinicopathological and immunohistochemical analysis of six cases.

Small cell carcinoma arising in the esophagus is a relatively rare disease. In the more common small cell carcinoma of the lung, the diagnostic significance of several new markers has been recently reported. This study used immunohistochemical techniques in addition to clinicopathological analysis, in order to clarify the utility of newer markers as biological parameters or as diagnostic tools. Six patients with small cell carcinoma of the esophagus were clinicopathologically analyzed. Immunohistochemical staining was performed using primary antibodies for bombesin, CD56 and CD57 in addition to conventional endocrine markers chromogranin A, neuron specific enolase and synaptophysin. All patients died within 2 years of surgery due to cancer recurrence, whether or not they had received adjuvant therapy. Pathological stages ranged from IIa to IVb and lymph node metastasis was observed in five cases. Of the six cases, four showed a positive reaction for bombesin and five were positive for CD57. In contrast, no cases revealed a positive reaction for CD56. The one case to survive 24 months after surgery was not shown to express bombesin, CD56 or CD57. Small cell carcinoma of the esophagus demonstrated an unfavorable prognosis. The study suggested that in this disease, bombesin and CD57 (but not CD56) were useful as biological markers, predicting clinical outcome rather than having diagnostic significance.

Aged↗

Clinical evaluation of pioglitazone in patients with type 2 diabetes using alpha-glucosidase inhibitor and examination of its efficacy profile.

AIM: Pioglitazone is considered to reduce insulin resistance. This study was conducted to evaluate the efficacy, safety and clinical profile of pioglitazone in patients whose type 2 diabetes were poorly controlled with alpha-glucosidase inhibitor alone or alpha-glucosidase in combination with sulfonylurea. METHODS: Twenty patients with type 2 diabetes were treated with pioglitazone (30 mg q.d.) orally for 16 weeks. RESULTS: There were significant reductions in HbA1C, FPG and postprandial plasma glucose at week 16. As adverse events, oedema, hypoglycaemia-like reaction, increases in LDH, CPK, etc. were noted. There was no significant change in TNF-alpha. Leptin levels increased significantly at week 16 and were still increasing 4 weeks after the treatment. Per cent body fat was almost constant throughout the study period. When efficacy was classified by demographic variables, pioglitazone was found to be more effective in the subjects who had a higher postprandial 2-h plasma glucose level, leptin level or per cent body fat value. CONCLUSION: Pioglitazone was considered to be effective when used in patients whose type 2 diabetes were poorly controlled with alpha-glucosidase inhibitor alone or alpha-glucosidase in combination with sulfonylurea.

Adult↗

Presence of pannus-like tissue on osteoarthritic cartilage and its histological character.

OBJECTIVE: To investigate and characterize pannus-like tissue which is often present on osteoarthritic articular cartilage. DESIGN: Cartilage specimens from 15 knee and five hip joints of patients with osteoarthritis (OA) undergoing arthroplasty were stained for HE and Safranin-O. They were also immunostained by antitype I collagen, type II collagen, CD68, IL-1beta and MMP3 antibodies. RESULTS: Ninety percent of joints have pannus-like tissue on the articular surface, preferentially in a marginal area. The articular cartilage was divided into three regions according to the location: the marginal zone, the intermediate zone and the paraeburnated zone. Pannuslike tissue in OA knee joint occurred 45.9%, 27.5% and 11.1% of the surface of each region respectively. Histologically, pannus-like tissue could be classified into the vascular type and the fibrous type. Extracellular matrix of both types of tissues were negative for Safranin-O and type II collagen, but positive for type I collagen. IL-1beta and MMP3 expressing cells are predominant in pannus-like tissue, whereas CD68 positive cells were infiltrated in only a few samples. Vascular type tissue kept continuity with bone marrow suggesting mesenchymal origin. CONCLUSION: Pannus-like tissue exists in advanced OA cartilage, preferentially in the marginal zone. It expressed IL-1beta and MMP3, which strongly suggests that it contributes to cartilage degradation.

Aged↗

Rectosigmoidal bladder utilizing an intussuscepted ileal segment: a surgical technique for urinary diversion.

A novel technique of urinary diversion was designed by interposition of an intussuscepted ileal segment between the ureters and the rectosigmoidal pouch, thus preventing ureteral reflux as well as stenosis at the uretero-enteric anastomosis, possible occurrence of urocolonic carcinoma, and frequent evacuation or incontinence. Since all the procedures were limited to the lower abdominal cavity, the surgical invasiveness was compatible with that of an ileal conduit. Our early experience in 15 patients showed that this technique can be considered for those in whom the urethra is not available.

Adult↗

Total cystoprostatectomy in the treatment of locally advanced prostate carcinoma.

OBJECTIVE: Locally advanced prostate carcinoma frequently causes lower urinary tract symptoms and is a clinical challenge when radiation and/or hormone therapy fail. We investigated whether cystoprostatectomy with urinary diversion benefits patients with locally advanced prostate carcinoma in terms of quality of life and prognostic outcome. PATIENTS AND METHODS: Between 1989 and 2001, we performed 15 cystoprostatectomies for stage C-D1 prostate carcinoma with bladder neck involvement. Of these patients, 5 underwent ileal conduit, 8 rectal bladder, 1 Koch pouch, and 1 ureterocutaneostomy. All the patients received neoadjuvant and/or adjuvant hormonal therapy. In the same period, 28 patients underwent retropubic prostatectomies and 15 patients received hormone therapy alone for stage C-Dl disease. These patients were included as references. RESULTS: Lower urinary tract symptoms caused by bladder involvement were controlled well until the end of follow-up for all the patients in the cystoprostatectomy group. There was no statistically significant difference in QOL score assessed with the EORTC QLQ-C30 questionnaire between the prostatectomy group and the cystoprostatectomy group, while that in the hormone therapy group was lower than those in the surgery groups. There was no statistically significant difference in 5-year PSA-relapse-free survival among cystoprostatectomy, prostatectomy, and hormone therapy groups. Patients in the hormone therapy group died earlier than those in the prostatectomy group (p = 0.02), while those in the cystoprostatectomy group did not. CONCLUSION: These results suggest that total cystoprostatectomy with urinary diversion is a valid option, in terms of disease control and QOL, for prostate cancer patients whose tumor is infiltrating into the bladder.

Aged↗

Molecular cloning of porcine neuronatin and analysis of its expression during pituitary ontogeny.

We cloned and sequenced two types (alpha and beta type) of cDNA from the porcine anterior pituitary cDNA library, encoding neuronatin that has been cloned as a gene expressed by the fetal developing brain. Nucleotide sequences of alpha and beta type were identical except for two gaps, suggesting that they were produced by an alternative splicing. The amino acid sequences showed a high homology (more than 94 %) compared to those of other mammals, including human, rat, and mouse. In this study, RT-PCR was performed for the RNA samples prepared from the porcine fetal and postnatal pituitaries. The results showed that two types of neuronatin are expressed through the fetal stages, from day 40 to day 110 in both sexes. The relative amounts of alpha to beta type reversed just after birth in both sexes, and both amounts increased further in the postnatal anterior pituitary. This increased expression after birth is quite different from the brain in which the expression of neuronatins decreased, indicating the distinct role of the neuronatin in pituitary and brain. Finally, we found a pituitary cell type specific localization, especially in gonadotroph cell lines LbetaT2, of beta-neuronatins.

Amino Acid Sequence↗

Occipital hypoperfusion in Parkinson's disease without dementia: correlation to impaired cortical visual processing.

OBJECTIVE: The purpose of this study was to analyse changes in regional cerebral blood flow (rCBF) in Parkinson's disease (PD) without dementia. METHODS: Twenty eight non-demented patients with PD and 17 age matched normal subjects underwent single photon emission computed tomography with N-isopropyl-p-[(123)I]iodoamphetamine to measure rCBF. The statistical parametric mapping 96 programme was used for statistical analysis. RESULTS: The PD patients showed significantly reduced rCBF in the bilateral occipital and posterior parietal cortices (p<0.01, corrected for multiple comparison p<0.05), when compared with the control subjects. There was a strong positive correlation between the score of Raven's coloured progressive matrices (RCPM) and the rCBF in the right visual association area (p<0.01, corrected for multiple comparison p<0.05) among the PD patients. CONCLUSIONS: This study showed occipital and posterior parietal hypoperfusion in PD patients without dementia. Furthermore, it was demonstrated that occipital hypoperfusion is likely to underlie impairment of visual cognition according to the RCPM test, which is not related to motor impairment.

Aged↗

Attenuated nuclear shrinkage in neurones with nuclear inclusions of SCA1 brains.

BACKGROUND: Spinocerebellar ataxia type 1 (SCA1) is one of the autosomal dominant neurodegenerative disorders commonly linked to pathological expansion of the CAG repeat of the relevant gene. Nuclear inclusions and neurodegeneration are both triggered by this pathological expansion of the CAG/polyglutamine repeat on ataxin-1, but it remains to be determined whether or not nuclear inclusion formation is associated with accelerated neurodegeneration. OBJECTIVE: To examine the influence of nuclear inclusions on nuclear size and deformity in human brains from patients suffering from SCA1. MATERIAL: Pontine sections of brains obtained at necropsy from seven patients with SCA1 and five controls. METHODS: The size and deformity of each neuronal nucleus was quantified. Nuclei with and without inclusions were examined separately to assess the possible influence of nuclear inclusions on neurodegeneration. RESULTS: Nuclear shrinkage and deformity were more marked in SCA1 brains than in controls. This shrinkage was attenuated in neurones containing nuclear inclusions. CONCLUSIONS: The existence of nuclear inclusions in SCA1 is presumably linked to a mechanism that attenuates rather than accelerates nuclear shrinkage. This in vivo finding may provide a clue to constructing a rational therapeutic strategy for combating neurodegeneration associated with nuclear inclusions.

Adult↗

Evidence that experimentally induced sleep bruxism is a consequence of transient arousal.

Spontaneous rhythmic masticatory muscle activity (RMMA) during sleep occurs more frequently following spontaneous transient micro-arousal in patients with sleep bruxism (SB) and normal controls. Here, we tested the hypothesis that an experimental arousal would be followed by an increase in RMMA. We identified RMMA on polygraphic recordings taken before and after sensory stimulation to induce experimental arousal in eight SB patients and eight matched normal subjects. The rate of experimental arousal and the level of resting electromyographic activity in masseter and suprahyoid muscles during sleep did not differ between the groups. In both, muscle tone and heart rate increased during the experimental arousal. Although post-arousal RMMA occurred in all SB patients, it was seen in only one normal subject. Moreover, tooth-grinding occurred during 71% of the evoked RMMA in SB patients. These results support the hypothesis that SB is an exaggerated form of oromotor activity associated with sleep micro-arousal.

Adult↗

Neurobiological mechanisms involved in sleep bruxism.

Sleep bruxism (SB) is reported by 8% of the adult population and is mainly associated with rhythmic masticatory muscle activity (RMMA) characterized by repetitive jaw muscle contractions (3 bursts or more at a frequency of 1 Hz). The consequences of SB may include tooth destruction, jaw pain, headaches, or the limitation of mandibular movement, as well as tooth-grinding sounds that disrupt the sleep of bed partners. SB is probably an extreme manifestation of a masticatory muscle activity occurring during the sleep of most normal subjects, since RMMA is observed in 60% of normal sleepers in the absence of grinding sounds. The pathophysiology of SB is becoming clearer, and there is an abundance of evidence outlining the neurophysiology and neurochemistry of rhythmic jaw movements (RJM) in relation to chewing, swallowing, and breathing. The sleep literature provides much evidence describing the mechanisms involved in the reduction of muscle tone, from sleep onset to the atonia that characterizes rapid eye movement (REM) sleep. Several brainstem structures (e.g., reticular pontis oralis, pontis caudalis, parvocellularis) and neurochemicals (e.g., serotonin, dopamine, gamma aminobutyric acid [GABA], noradrenaline) are involved in both the genesis of RJM and the modulation of muscle tone during sleep. It remains unknown why a high percentage of normal subjects present RMMA during sleep and why this activity is three times more frequent and higher in amplitude in SB patients. It is also unclear why RMMA during sleep is characterized by co-activation of both jaw-opening and jaw-closing muscles instead of the alternating jaw-opening and jaw-closing muscle activity pattern typical of chewing. The final section of this review proposes that RMMA during sleep has a role in lubricating the upper alimentary tract and increasing airway patency. The review concludes with an outline of questions for future research.

Adult↗

Retrievable vena cava filter placement during treatment for deep venous thrombosis.

The purpose of our study is to evaluate the safety of insertion and removal of the retrievable vena cava filter and the efficacy of this filter in preventing pulmonary embolism during treatment of stenosis or obstruction of the lower extremity due to deep venous thrombosis. We retrospectively evaluated placement of 10 filters in 6 patients with lower extremity deep venous thrombosis who had undergone various treatments, including those utilizing techniques of interventional radiology. Worsening of or the new formation of pulmonary embolism was prevented in all patients. All attempts at both implantation and retrieval of the filter were safely accomplished. No complication related to filter placement occurred. Filters were left in the vena cava for permanent use when deep venous thrombosis was refractory to treatment. These results demonstrate that both placement and removal of the retrievable vena cava filter can be accomplished safely and that this type of filter is useful to prevent pulmonary embolism during treatment of deep venous thrombosis of the lower extremity. Further, the use of a retrievable vena cava filter might be preferred over that of a temporary vena cava filter, especially if further implantation of a filter becomes necessary since replacement with a permanent filter would not be required when using a retrievable vena cava filter.

Adult↗