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Biomedical subjects

K Hojo

Publications and source records attributed to K Hojo.

At least 145 records · Page 8Linked to original sources

Augmentation of guinea pig T lymphocyte proliferative response to antigens in the presence of purified B cells.

The effect of supplemental B lymphocytes on the antigen-induced in vitro proliferative response of highly purified lymph node T cells was studied in two immune systems of complete Freund's adjuvant (CFA) and testicular antigen (TA) sensitized guinea pigs. When the T lymphocytes obtained from animals 2 weeks after CFA sensitization, though unresponsive to purified protein derivate of tuberculin (PPD) by themselves, were cultured together with mitomycin C-treated autologous B (Bm) lymphocytes (1:0.5 ratio), they responded well to PPD. The enhancing effect of Bm lymphocytes was less than that of mitomycin C-treated macrophages (M phi m) from the same animals. Analogous helper effect of Bm lymphocytes on the T cell proliferation was observed also in TA-sensitized animals. Additionally, it is noteworthy that the PPD-induced proliferation of T lymphocytes at 2 weeks after CFA sensitization was absolutely dependent on M phi and B lymphocytes, whereas T lymphocytes at 10--14 weeks exhibited a low but significant response by themselves, although their response to PPD was markedly augmented with supplemental M phi m or Bm lymphocytes.

Animals↗

Lymphocyte proliferative response in vitro and its cellular dependency in guinea-pigs with experimental allergic orchitis.

The development of cellular hypersensitivity was measured by the proliferative response of lymph node cells in vitro and a skin test to partly purified testicular antigen. There was a slight stimulation of lymph node cells and of the delayed cutaneous response at 1-2 weeks after sensitization with testicular antigen in Freund's complete adjuvant and then, after a decline in response, there was a pronounced peak at 6 weeks after sensitizaton. The early response coincided with the onset and active inflammatory stage of the effect on the testis, while the major peak was consistent with a state of aspermatogenesis. The proliferative response of unseparated lymph node cells could not be attributed to the function of T or B cells acting alone, although at 6 weeks after sensitization B-cell populations did become slightly responsive to antigen. The response of T lymphocytes was enhanced by the presence of B lymphocytes or peritoneal macrophages at 2 and 6 weeks after sensitization, but B cells did not appear to interact with macrophages. We conclude that T cells are essential to the proliferative response of lymph node cells during the induction of experimental allergic orchitis in guinea-pigs.

Animals↗

Macrophage requirements of PPD-induced blastogenic factor production by T and B lymphocytes in the guinea-pig.

An attempt has been made to characterize the cell type which releases blastogenic factor(s) (BF) on purified protein derivative (PPD) stimulation in complete Freund's adjuvant (CFA)-sensitized guinea-pig system and, further, to examine whether macrophages (Mphi) are required for antigen activation of T or B lymphocytes to produce this lymphokine. Both T and B lymphocyte populations from guinea-pigs 2-3 weeks after CFA sensitization (early-stage T and B cells) failed to produce significant amounts of BF in response to PPD, whereas both the populations from 10 to 14 weeks after sensitization (late-stage T and B cells) acquired the ability to produce BF by themselves. It is noteworthy that readded autologous Mphi not only functioned well to augment BF production by the late-stage T and B cells but also completely made up for the inability of the early-stage T and B cells to produce BF. From these data it is reasonable to conclude that in the guinea-pig sensitized T and B cells can both release BF on exposure to PPD and that Mphi either reconstitute or augment the BF synthetic response of T and B cells.

Animals↗

Acute diffuse interstitial fibrosing pneumonitis and bilateral renal cortical necrosis.

An autopsy case of a 69-year-old male with acute diffuse interstitial fibrosing pneumonitis complicated by bilateral renal cortical necrosis was presented. Autopsy revealed acute diffuse interstitial fibrosing pneumonitis, bilateral renal cortical necrosis, non-bacterial thrombotic endocarditis, involving the aortic and mitral valves, and some interesting vascular lesions, dissemination of fibrinoid change of arterioles and fibrin thrombus of small vessels in various organs; accumulation of polymorphonuclear leukocytes in the lumen of the smaller interlobular arteries and arterioles of the kidney with cellular infiltration and disintegration of the wall; severe disorganization of the wall with intraluminar and intramural fibrinous exudation in smaller branches of the hepatic artery; diminution and disarrangment of muscle fibers and patchy hyalinization in the media of the renal and interlobar arteries. The inter-relationship between acute diffuse interstitial fibrosing pneumonitis, bilateral renal cortical necrosis which may be regarded as a 'hallmark' of the generalized Shwartzman reaction, and disseminated intravascular coagulation was discussed.

Acute Disease↗

Effects of desensitization on different kinds of in vitro PPD-induced response of lymph node lymphocytes from tuberculin-sensitive guinea pigs.

Guinea pigs rendered hypersensitive to tuberculin 2 to 3 weeks (early stage) or 10 to 14 weeks (late stage) after sensitization with complete Freund's adjuvant could be completely desensitized by a single or double injections of a sufficient amount of PPD (purified protein derivative). Lymph node cells from such desensitized animals 48 to 72 hr after the challenge showed a considerable reduction of the ability to produce blastogenic factor and skin reactive factor upon PPD-stimulation, whereas the macrophage migration inhibitory factor activity remained still unaffected. As regards antigen-induced 3H-thymidine incorporation in vitro, lymph node cells from animals desensitized in the late stage after sensitization showed no substantial reduction in the degree of enhanced DNA synthesis upon PPD-stimulation, although the desensitization in the early stage resulted in a significant loss of this activity. These results suggest the possibility that desensitizing challenge does not bring about a uniform and regular effect on every lymphocyte subpopulations relevant to different functions and, in addition, indicate that there are some exceptions to the compartmentalization concept of antigen-reactive lymphocytes.

Animals↗

[Neuropsychological studies of two subjects after the transection of the splenium of the corpus callosum. (Part 2. The auditory recognition by the dichotic listening test) (author's transl)].

We made the neuropsychological auditory studies of two right-handed subjects who had undergone the transection of the splenium of the corpus callosum for the pineal operation (the teratoma by the histopathological examination). The transection grades were 2.0 cm and 2.5 cm. The truncus and splenium of the second subject were flat by the compression of the tumor. We examined these subjects by the some audiolocigal methods. 1. Pure tone audiometry. 2. Fixed frequency Békésy audiometry. 3. SISI test (short increment sensitivity index test). 4. Speech audiometry. 5. Distorted speech test (filtered speech test). 6. Binaural fusion test. 7. Dichotic listening test. The tasks used for the dichotic listening test were following. Different digits (one pair, three pairs), different words (from two to four syllables) and different vowels and consonants were presented simultaneously to the two ears by means of a dual-channel tape recorder with stereophonic earphone. The result shows that the first subject (whose section of the spelenium was 2.0 cm) shows a slight but not significant superiority on the right ear to the one pair digits and words (p less than 0.1), and the second subject (whose section of the splenium was 2.5 cm and whose splenium and truncus of the corpus callusum were flatten by the compression of the tumor) shows a significant superiority on the right ear to the one pair digits, words, three pairs digits and vowels (p less than 0.05). But there was no definitive abnormalities at the pure tone audiometry, the fixed frequency Békésy audiometry, SISI test, distorted speech test and binaural fusion test of two cases. The result shows that the commissure fibres of the auditory perception of the speech of two hemispheres connect through from splenium to the truncus of the corpus callosum.

Brain Neoplasms↗

[Neuropsychological studies of two subjects after the transection of the splenium of the corpus callosum (Part 3. The tactile recognition) (author's transl)].

We made the neuropsychological tactile studies of two right-handed subjects who had undergone the transection of the splenium of the corpus callosum for the pineal operation (the teratoma by the histopathological examination). The transaction grade was 2.0 cm and 2.5 cm. In this paper we examined the tactile recognition neuropsychologically: A. Superficial sensory modalities: light touch, pain perception, temperature discriminations. B. Deep sensory modalities: vibration perception, position sense, motor sense. C. Perception of material: rough or smooth, heavy or light, hard or soft. D. Perception of size: appreciation of shape in two dimentions: circle, triangle, square, cross, rhomb, appreciation of form in three dimensions: ball, column, cone, trignonal prism, cube. E. Identification of simple objects: eraser, pencil, hair pencil, fountainpen, telephone, glasses. F. Identification of japanese letters: Kana (phonetic symbols) and Kanji (essentially nonphonetic logographic symbols representing lexical morphemes). According to the papers of Akelaitis, Van Vleuten, Goldstein, the subjects after the transection of the corpus callosum could name the objects and the card board letters placed in their right hands with their eyes closed, but they could not name in their left hand by contrast. In our subjects, the identification of simple objects and the identification of japanese letters were complete good. But they had the neuropsychological visual and auditive disorders. The result shows that the commissure fibres of the identification of the simple objects and letters of two hemispheres does not connect through the splenium of the corpus callosum.

Agnosia↗

A safe method of intrahepatic biliary drainage in obstructive jaundice.

In malignant disease with severe obstructive jaundice, survival after operative intervention is extremely low. Simple external biliary drainage is desirable for these patients, as a preliminary procedure for radical operation or long-term palliation. Intrahepatic biliary drainage at the anterior edge of the liver can be performed easily and safely under local anesthesia in case of obstruction of the proximal bile ducts, just as cholecystostomy is indicated for obstruction of the common bile duct.

Bile Duct Neoplasms↗

Dissociation of blastogenic factor production and lymphocyte transformation of guinea pig lymphocytes stimulated with tuberculin PPD.

In vitro lymphocyte transformation of guinea pig lymph node cells induced by tuberculin PPD was essentially eliminated by treatment with 5-bromo-2-deoxyuridine and light. The remaining cell population was still capable of producing blastogenic factor and further, the amount of blastogenic factor released was comparable to that from the intact population in the same interval of culture. This result favors the conception that cells producing blastogenic factor in response to antigen are distinct from the cells responding to the antigen by DNA synthesis and proliferation.

Bromodeoxyuridine↗