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Biomedical subjects

K Kitamura

Publications and source records attributed to K Kitamura.

At least 865 records · Page 48Linked to original sources

[Experimental head injury of rabbits using pendulum impactor. An electron microscopic study].

Brain damage in the early stage of experimental head injury was studied under electron microscope, especially with respect to the permeability of the blood brain barrier and damage to nerve fibers. Lightly anesthetized rabbits were treated by intravenous injection of horseradish peroxidase (150-250 mg/kg) and were subjected to occipital impacts with a pendulum impactor. The animals were then perfused with a 2.5% glutaraldehyde mixture. Small blocks of the brain were sampled, incubated, postfixed, and embedded in Epon. These sections were observed under an electron microscope without staining. The authors' criteria of concussion have been previously published. There were three nonconcussion, 11 nonlethal concussion and seven lethal concussion animals. All cases of lethal concussion showed subarachnoid hemorrhage (SAH) in the brainstem and 57% of them showed microscopic parenchymal perivascular hemorrhages in the brainstem. Fifty-five percent of the nonlethal concussion cases showed SAH in the brainstem with a little parenchymal hemorrhage. The nonconcussion cases showed no hemorrhagic change except contusions and/or SAH of the cerebellum. Hemorrhagic changes were frequently seen in the cerebrum and cerebellum of nonlethal and lethal concussion cases without correlation to the severity of concussion. Under electron microscope, nonconcussion cases showed mild splitting of myelins. In nonlethal concussion cases, swelling of perivascular astrocytic feet was seen to a moderate degree in the cerebrum, pons, and medulla oblongata and damage to axons and myelins were mainly seen in the pons and medulla oblongata. Many cored dense bodies containing peroxidase were diffusely recognized in vascular endothelial cells. In lethal concussion cases, beside findings seen in nonlethal concussion, intravascular peroxidase was seen to leak from the intravascular space through an opened tight junction to the extracellular space, axons and neurophils.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Clivus epidural hematoma. Case report.

A rare case of epidural hematoma of the clivus is reported in an 11-year-old girl involved in a traffic accident which caused a severe hyperextension injury. Only one similar case has been reported in the literature. The mechanism for the formation of the hematoma of this region is discussed.

Child↗

[Auricular hematoma--case report of ruptured othematoma and bibliographic review].

Auricular hematoma is not rare condition and its prognosis has been considered to be good in Japanese textbooks. Recurrence of the hematoma, however, frequently occurs by use of simple aspiration or incision, and a pressure dressing. In this paper, we report a case of ruptured othematoma and review the biliographies concerning the pathology and treatment of othematomas. A 37-year-old man sustained a fist blow to his left ear at the beginning of May, 1989. He was first seen with auricular hematoma on July 4, but refused a surgical treatment. The laceration of the skin overlying the hematoma occurred by once more fist blow on July 26, with the upper auricle divided into anterior and posterior parts. The auricular cartilage was broken into several pieces, some of which attached to the anterior side and the others to the posteriors side. Under general anesthesia, fibrin glue was applied to the dead space after irrigation, minimal debridement, and removal of the clots. Four horizontal mattress sutures were put through the entire pinna after the anterior skin was protected by fluffed gauze with antibiotic ointment and the posterior skin by buttons. The dressing was allowed to remain in place ten days and was then removed. Nine months after the operation the pinna appeared almost normal. In recent reports, the othematoma is considered to occur between the perichondrium and the cartilage, or within the cartilage. Various techniques have been applied to treat the othematoma, which are classified into three types: incision and drainage, pressure dressing with splinting mold, or with mattress suture. Treatment of choice is discussed, with reviewing the advantages and disadvantages of each method.

Adult↗

Actions of cromakalim on ionic currents recorded from single smooth muscle cells of the rat portal vein.

The effects of cromakalim (BRL34915), a novel K channel opener, on ionic currents in dispersed smooth muscle cells of the rat portal vein were investigated. Application of cromakalim (greater than 3 microM) generated an outward current, the reversal potential of which (-79 mV) was almost the same as the theoretical K equilibrium potential (-80 mV) under the experimental conditions used. When the Ca in the physiological salt solution (PSS) was replaced with Mn, the cromakalim-induced outward current was inhibited markedly. When 4 mM ethylene glycol bis(beta-aminoethyl ether(N,N'-N,N'-tetraacetic acid (EGTA) was added to the pipette solution (bath solution, Ca-free PSS + Mn), cromakalim inhibited the outward current evoked by command pulses. Using a pipette solution containing high Cs with 4 mM EGTA and a bath PSS containing 2.5 mM Ca with 1 microM tetrodotoxin, the Ca inward current was isolated. Cromakalim (greater than 3 microM) inhibited the Ca inward current in a voltage- dependent manner. Cromakalim (30 microM) inhibited the Ca inward current to 0.6 times the control. The decay of the inward Ca current comprised fast and slow components. Cromakalim inhibited the latter component and shifted the voltage-dependent inactivation curve of this current to the left (more hyperpolarized direction) in a parallel manner and delayed recovery from inactivation as estimated using a double pulse protocol. By using a pipette solution containing high Cs with 4 mM EGTA and Ca-free PSS containing 2.5 mM Mn in the bath, Na inward currents, blocked by tetrodotoxin (IC50 = 10 nM), were evoked by depolarizing pulses. Cromakalim (up to 30 microM) had no effect on the Na inward current.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗

[Myelin proteins].

Explore the source record for details and available documents.

2',3'-Cyclic-Nucleotide Phosphodiesterases↗

[A case of non-paralytic pontine exotropia due to pontine tegmentum lesion confirmed by magnetic resonance imaging and electronystagmography].

A case with non-paralytic pontine exotropia (NPPE) due to brainstem infarction is reported. A 77-year-old hypertensive man suddenly developed dizziness, double vision, dysarthria, and right ataxic hemiparesis. Oculomotor findings on admission consisted of: (1) full right exotropia in the primary position; (2) complete adductive paralysis of the left eye with slight preservation of convergence; (3) tonic deviation of the right eye to the full abducting position with right-beating nystagmus after an immediate forward gaze. The leftward saccades showed multiple saccades with slow velocity on electronystagmography (ENG). The right exotropia disappeared and the slight adductive paresis of the left eye remained with right monocular nystagmus seven weeks after the onset. Magnetic resonance imaging (MRI), which was performed nine weeks after the onset, disclosed a small lesion with high intensity involving the left medial longitudinal fasciculus (MLF) on T2-weighted spin echo image. The leftward saccades showed multiple saccades with normal velocity eleven weeks after the onset. The hypofunction of unilateral PPRF with ipsilateral MLF lesion probably causes the contralateral NPPE.

Aged↗

[A case with reconstruction of the floor of the oral cavity and mandibular region with the D-P flap after resection of giant keloid and radiation scar of the mandibular].

The floor of the oral cavity and mandibular of a 27-year-old female was reconstructed with the D-P flap after resection of a giant keloid in the submandibular region and a radiation scar of the mandibular. The mandibular was reconstructed with a transplantation graft of the iliac bone and the functional properties and appearance were good.

Adult↗

[Inhibitory effects of a hot water extract from Japanese tea on the cell growth of mutans streptococci].

This study was undertaken to examine the effect of a hot water extract from Japanese tea on the cellular growth of mutans streptococci in vitro. The extract contained polyphenol compounds, mainly catechin derivatives. Few fluoride components were contained in the extract. Streptococcus mutans MT8148R (serotype c) and S. sobrinus MT6715 (serotype g) strains were used in the present study. The organisms (10-10(7) CFU/ml) were cultured in brain heart infusion (BHI) and tryptose phosphate (TP) broths containing the tea extract (0-8 mg/ml). After incubation for 24-48 hours the cell numbers in the cultures were determined. Furthermore, cell growth of these strains on BHI agar plates containing the extract (0-2 mg/ml) were examined. The results obtained were as follows: 1. The tea extract (2-8 mg/ml) in BHI broth inhibited remarkably the growth of S. mutans and S. sobrinus (inoculum size; 10(6) CFU/ml). No difference in susceptibility to the tea extract between S. mutans and S. sobrinus was noted. 2. The cell growth of both strains in TP broth was inhibited by the tea extract. However S. sobrinus was found to be more sensitive to the extract than S. mutans. 3. Growth of S. sobrinus cells on the BHI agar plate was suppressed by the tea extract more effectively than that of S. mutans. These results suggest that the tea extract would be useful as an anti-cariogenic agent.

Catechin↗

[Host factors that changes the distribution of immunotoxin].

Mouse monoclonal antibody A 7, which was raised against human colon cancer, was used for preparing the conjugates with neocarzinostatin, mitomycin C and adriamycin. The tissue distribution of these three conjugates were examined in athymic nude mice transplanted with human colon cancer. The distribution in tumor was different in these three conjugates. The route of administration of the conjugate affected its distribution in tumor tissues. In the case of tumor transplanted in the back of mice, intravenous administration seemed to superior to intraperitoneal one. In clinical trials of immunoconjugate composed of A 7 and polypeptide anticancer drug neocarzinostatin (A 7-NCS), human anti-mouse antibody (HAMA) was observed in most cases without serious immune response such as anaphylactic shock. Human antibody against neocarzinostatin could not be detected in any case receiving A 7-NCS.

Animals↗

[Missile therapy of colorectal and pancreatic cancers--clinical trial of monoclonal antibody, A7-NCS, in 73 patients with colorectal and pancreatic cancers].

Monoclonal antibody-drug conjugate, A7-NCS, was applied for 73 patients with colorectal and pancreatic cancer, including metastasis of liver, lung and peritoneum. Monoclonal antibody A7, from a mouse splenocyte immunized against human colon cancer was bound covalently to Neocarzinostatin (NCS), Mitomycin C (MMC) and Adriamycin (ADM) to form A7-NCS, A7-MMC and A7-ADM, respectively. Fifty-four patients with colon cancer, fifteen patients with postoperative liver metastasis of colorectal cancer and one patient with advanced pancreatic cancer were given A7-NCS intra-arterially. Two patients with postoperative lung metastasis of colon cancer were injected intra-venously and one patient with postoperative peritoneal metastasis of colon cancer was given it intraperitoneally. Three patients with liver metastasis showed evidence of tumor reduction on CT scan and three claimed pain relief. Postoperative survival of the patients with distant metastasis exhibited slightly higher survival rate in the patients with A7-NCS, as compared with the patients without A7-NCS. There was no serious adverse effect in the patients given A7-NCS. Human anti-mouse antibody (HAMA) was detected in all patients given the conjugate. Repeated injections of A7-NCS for several consecutive days following the first injection brought about the same A7 pattern as the first injection.

Aged↗

[Immunoresponses and efficacy after arterial infusion of immunoconjugate A7-NCS in patients with colon cancer].

We prepared an immunoconjugate, A7-NCS, of a mouse-derived anti-human colon cancer monoclonal antibody A7 and the macromolecular protein anticancer agent neocarzinostatin (NCS), and evaluated changes in human anti-mouse antibody (HAMA) by ELISA in the serum of patients intraarterially administered this agent. IgG and IgM class HAMA were detected in all patients, but no IgE class HAMA. In patients with stage V disease, the survival rate was higher in a group treated with A7-NCS at an NCS dose of 4,000 units or more than in that treated at an NCS dose of less than 4,000 units. In these patients, the survival rate was higher in a group treated with A7-NCS at an NCS dose of 4,000 units or more than in one not treated with it. These results suggest the usefulness of A7-NCS administration at high dose for prolonging survival of patients with advanced colon cancer.

Animals↗

Nicorandil opens a calcium-dependent potassium channel in smooth muscle cells of the rat portal vein.

The actions of nicorandil on ionic currents recorded from smooth muscle cells of the rat portal vein were investigated using patch-clamp technique. In the whole-cell voltage clamp experiments, nicorandil (greater than 30 microM) produced an outward current in a concentration-dependent manner. The reversal potential was -80 mV. The nicorandil-induced outward current was suppressed in the nominally Ca-free (2.5 mM Mn-containing) solution. Tetraethylammonium (greater than 1 mM) and 4-aminopyridine (greater than 1 mM) inhibited the nicorandil-induced outward current. Recordings of single K-channels showed that there were two types of K currents with different conductance (132 pS and 10 pS) in the smooth muscle cell membrane. Both channels were sensitive to intracellular Ca concentration. The 10-pS K-channel but not the 132-pS K-channel was activated by lowering the ATP concentration inside of the membrane. Low concentrations of tetraethylammonium (less than 1 mM) completely inhibited the 132-pS K-channel, but had no effect on the 10-pS K-channel. On the other hand, 4-aminopyridine (10 mM) inhibited the 10-pS K-channel but not 132-pS K-channel. Nicorandil (500 microM) applied to outside of the membrane increased the mean open-time and number of appearances but reduced slow component of the mean closed time of the 10-pS K-channel current, without affecting their amplitudes. Nicorandil (less than 500 microM) did not modify the 132-pS K-channel. From above results we concluded that nicorandil activates the Ca-dependent and ATP-sensitive K-channel in smooth muscle cells of the rat portal vein.(ABSTRACT TRUNCATED AT 250 WORDS)

4-Aminopyridine↗

Mucinous cystic neoplasm of the pancreas. Estimation of grade of malignancy with imaging techniques and its surgical implications.

The results of diagnostic imaging procedures, macroscopic and microscopic findings and clinical follow up data of 20 mucinous cystic neoplasms of the pancreas were retrospectively reviewed to determine the grade of malignancy and its surgical implications. The largest mean diameter was 8.9 cm for 10 malignant cases, 5.0 cm for two premalignant cases, and 3.1 cm for eight benign tumours. Ultrasonography or computed tomography or both, corresponded well with macroscopy. The 10 malignant and two premalignant lesions had intracystic mural nodules or extracystic solid components, while the eight benign specimens had neither nodules nor solid portions. Structural complexity seen on ultrasonography or computed tomography, which reflected the irregularity in size and shape of the cysts, internal septa, walls, and solid components, was severe in the 10 malignant and two borderline tumours and mild or moderate in the eight benign lesions. Angiography showed that five of the nine malignant tumours were hypervascular, while the two premalignant and four benign lesions were all avascular. Five of 10 patients with malignant tumours died of local recurrence or remote hematogenous metastases, and one with malignant disease was still alive with liver metastases at the time of writing. We propose that a careful preoperative estimate of the malignant potential of such cysts should be made based on the size of the tumour, the presence of mural nodules and solid areas, and the structural complexity on ultrasonography or computed tomography, as well as the amount of vascularity seen on angiography. Attention should be paid at follow up to the presence of local recurrence and haematogenous metastases in cases of malignant disease.

Adenocarcinoma, Mucinous↗

[A case of thymolipoma on the cervicomediastinal area].

Thymolipoma is a very rare mediastinal tumor. We reported a case of 52-year-old female with thymolipoma which was located in the cervicomediastinal area. The chest X-ray film revealed an abnormal shadow in the superior mediastinum. Computed Tomography (CT) clearly showed the existence of a large mass in the left side of the trachea. The angiogram showed that there was a stenosis on the left brachiocephalic vein. On June 13, 1988, median sternotomy was performed. A large tumor, about 5.5 x 13 x 5.5 cm, was found arising from the left cervical area. This tumor was excised completely and thymolipoma was diagnosed histopathologically. The post-operative course was very satisfactory.

Female↗

[Vesico-prostatic calculi treated by microexplosion lithotripsy: a case report].

A 48-year-old male suffering from neurogenic bladder due to spinal injury was admitted to our clinic with a chief complaint of macrohematuria. Examinations revealed some calculi located in the bladder and in the prostate. Microexplosion lithotripsy for the prostatic calculi (29 x 23 mm etc.) was performed via the urethra and for the vesical calculus (65 x 55 mm) via the suprapubic cystostomy channel. The calculi were fragmented and removed out completely.

Calculi↗