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T Koga

Publications and source records attributed to T Koga.

809 records · Page 45Linked to original sources
PubMedDate not supplied

Lung cyst formation in lymphocytic interstitial pneumonia: CT features.

OBJECTIVE: We performed this study to identify and characterize the CT findings of lymphocytic interstitial pneumonia (LIP). MATERIALS AND METHODS: The CT findings of two patients with LIP were reviewed and correlated with their histologic specimens. RESULTS: Chest CT of the two patients showed areas of increased attenuation in both lung fields which were associated with nodular and cystic lesions surrounding the peribronchovascular bundles. The most characteristic abnormality identified on CT was the presence of multiple cysts throughout both lungs. Macroscopic findings of lung biopsy specimens included multiple nodular and cystic lesions. CONCLUSION: This description of multiple pulmonary cysts formation in LIP is new.

Adult↗
PubMedDate not supplied

Spontaneous fall in blood pressure and reactivity of sympathetic nervous system in hospitalized patients with essential hypertension.

We evaluated whether reduction in sympathetic reactivity plays a major role in the spontaneous falls in blood pressure (BP) experienced during hospitalization by patients with essential hypertension. In the present case BP fell on the 2nd day of hospitalization. The responses of plasma catecholamines (CA) and BP to both handgrip and tilting were not altered during either the first 24 hours or the entire 7 days of hospitalization. The effect of phentolamine on BP was similar on the 1st, 2nd and 7th days. However, the resting levels of plasma norepinephrine before handgrip, tilting and phentolamine were significantly diminished on the 7th day, but not on the 2nd day. In conclusion, the diminution of sympathetic activity may be partly responsible for the hospitalization-induced fall in BP in the late stages.

Adult↗
PubMedDate not supplied

Renal failure due to cholesterol embolization following percutaneous transluminal renal angioplasty.

Percutaneous transluminal renal angioplasty was performed in a 63-year-old diabetic woman who had renovascular hypertension with solitary functioning kidney and diffuse atherosclerosis. Angioplasty was technically successful, while thereafter, fever and myalgia of legs occurred with gradual increases in blood urea nitrogen and creatinine. The patient became uremic over a month after angioplasty and was placed on dialysis. She died six months after angioplasty. Autopsy revealed cholesterol embolization in bilateral kidney, pancreas and spleen, causing subacute renal failure. It is suggested that careful assessment of the patient should be made when determining the need for renal angioplasty for renovascular hypertension with a solitary functioning kidney.

Aged↗
PubMedDate not supplied

Vitamin D3 analogues improve café au lait spots in patients with von Recklinghausen's disease: experimental and clinical studies.

Topical application of vitamin D3 analogues for 6 months was found to be effective in improving the pigmentation of café au lait spots in patients with von Recklinghausen's disease. Treatment of café au lait spots grafted onto nude mice with a vitamin D3 analogue caused suppression of bromodeoxy- uridine uptake in the cells of the basal layer. Vitamin D3 analogues also decreased melanin pigment in café au lait spots after 4 weeks of treatment. Thus, it is considered that long-term application of vitamin D3 analogues is effective both for improving the pigmentation of café au lait spots and suppressing the development of neurofibromas in patients with von Recklinghausen's disease.

Administration, Topical↗
PubMedDate not supplied

In vitro released interferon-gamma in the diagnosis of drug-induced anaphylaxis.

A 17-year-old Japanese male was referred with acute urticaria and anaphylaxis after the administration of PL (salicylamide, acetaminophen, anhydrous caffeine and promethazine methylene disalicylate) and Bufferin (aspirin and dialminate) for headache and a high grade fever. The results of prick test, patch test and drug-induced lymphocyte stimulation test with PL and Bufferin were all negative. The patient's peripheral blood mononuclear cells (PBMC) were cultured with or without PL for 72 hours, and the activity of interferon-gamma (IFN-gamma) in the culture supernatant was measured with EIA. A significantly high level of IFN-gamma was detected in PBMC from the patient, but very little in those from healthy control subjects with a history of exposure to PL. This finding may indicate the presence of drug-specific IFN-gamma producing T cells in patients with an anaphylactic shock reaction to medication. Assays that measure the drug-induced IFN-gamma production may thus be a useful diagnostic tool not only for identifying delayed-type hypersensitivity (DTH) to drugs, but also for predicting anaphylactic shock reaction to drugs.

Acetaminophen↗
PubMedDate not supplied

Gastric cancer with high telomerase activity shows rapid development and invasiveness.

Telomerase activity was reported to be activated in most immortal cells and cancers. As the clinical significance of telomerase activity in human gastric cancer is controversial, we investigated this activity using a telomeric repeat amplification protocol. The telomerase activity was tentatively defined by strength of activity as follows: 3+, observed with 0.06 microg of protein; 2+, observed with 0.6 microg of protein; 1+, observed with 6 microg of protein; 0, not observed under these three conditions. Telomerase activity was detected in 35 of 39 (89.7%) gastric cancer specimens. Tumors with high telomerase activities (2+/3+) tended to have a deeper invasion, lymphatic and vascular invasion, lymph node metastasis, liver metastasis, and peritoneal dissemination, as compared to findings in case of low telomerase activities (-/1+). Thus, telomerase activity of gastric cancer tissue may reflect the malignant potential of the tumor and intensive postoperative care might be required for such patients.

Adult↗
PubMedDate not supplied

Erythema induratum in a patient with active tuberculosis of the axillary lymph node: IFN-gamma release of specific T cells.

A 57-year-old woman with tender nodular lesions on her legs, arms, buttocks and face is reported as a case of erythema induratum (EI) with active tuberculosis of axillary lymph nodes. Both skin nodular lesions and lymph nodes responded positively to antituberculous therapy. The patient's peripheral blood mononuclear cells showed a high proliferation and produced interferon-gamma (IFN-gamma) in response to purified protein derivative (PPD). These findings indicate the possibility that PPD-specific T cells, capable of producing IFN-gamma, are likely to be involved in the formation of EI as a type of delayed-type hypersensitivity response to mycobacterial antigens at the site of skin lesions.

Axilla↗
PubMedDate not supplied

Immunohistochemical detection of interferon-gamma-producing cells in dermatophytosis.

Skin lesions of dermatophytosis are thought to be a result of a T cell-dependent inflammatory response that is mediated by various cytokines. We examined whether IFN-gamma-positive cells (as expression of Th1 response) were present in the skin lesions of dermatophytosis in situ by immunohistochemical techniques. Mixtures of CD4-positive T cells and CD8-positive T cells were found to be present in the dermal infiltrates of the lesions. Considerable numbers of CD1a-positive cells were detected in the upper dermis and epidermis. A marked accumulation of CD68-positive cells was found in the upper dermis. IFN-gamma-positive cells were present in the upper dermis of the lesions. The pattern of IFN-gamma staining appeared to be intracellular in mononuclear lymphoid cells. The staining was considered to be highly specific because it could be completely blocked by preabsorption with recombinant IFN-gamma. Our data support the hypothesis that the skin lesions of dermatophytosis may be associated with a Th1 response. Th1 response, which is characterized by IFN-gamma release, is thought to be involved in the host defense against dermatophytes and to reflect cutaneous reaction in dermatophytosis.

Animals↗
PubMedDate not supplied

Immunohistochemical localization of activated and mature CD83+ dendritic cells in granulomas of sporotrichosis.

Dendritic cells (DC) are considered to be the most potent antigen-presenting cells (APC) and CD83 is expressed at a high level on immune-competent, activated and mature DC. In order to obtain insight into the immune response in sporotrichosis, we searched immunohistochemically for CD83+ DC in the granulomatous skin lesions of patients. A small but significant subpopulation of CD83+ DC (approximately 0.2 to 0.8% of inflammatory cells) was found. The most common distribution pattern of CD83+ DC was as clusters with mononuclear lymphoid cells within the granulomas. In addition, CD83+ DC were occasionally scattered around the granulomas. High-intensity staining of CD83 antigens was detected not only on the surface, but also in the cytoplasm of DC. No CD83+ DC were observed in the epidermis. A considerable amount of CD1a+ cells were detected in the epidermis, papillary dermis and around the granulomas, but CD1a+ cells were rarely found within the granulomas. There were large numbers of CD68+ monocytes and macrophages in the granulomas. These results indicate that activated and mature DC may play a role in the immune response to sporotrichosis.

Antigens, CD↗
PubMedDate not supplied

Heparanase gene expression and metastatic potential in human gastric cancer.

BACKGROUND: Heparanase has been reported to play an important role in tumor progression and metastasis. We examined the relationship between heparanase mRNA expression and biological factors regarding invasion and metastasis of human gastric cancer. MATERIALS AND METHODS: In 63 human gastric carcinomas, 42 adjacent normal gastric tissues and four gastric cancer cell lines, heparanase mRNA expression was evaluated using reverse transcription PCR (RT-PCR). Total RNA obtained from human peripheral blood (PB) leucocyte and placenta were used as positive controls. The relationship between heparanase mRNA expression and various clinicopathological factors were analyzed. RESULTS: The heparanase mRNA expression evaluated with RT-PCR revealed that 31 out of 63 gastric cancer tissues (49%), 11 out of 42 normal gastric tissues (26%) and 4 gastric cancer cell lines were positive. The positive rate in cancer tissues was significantly higher than that in normal tissues (p<0.05). In the heparanase mRNA-positive cancer tissues, venous invasion was frequent (p<0.05) and the histological differential grade was significantly poorer than in negative cases (p<0.01). CONCLUSION: We propose that heparanase mRNA expression is involved in invasion and development of human gastric cancer and detection of this expression may be a factor related to metastasis and prognosis of such patients.

Female↗
PubMedDate not supplied

Alpha-adrenoceptor antagonistic effects and antihypertensive activity of SGB-1534 in conscious normotensive and deoxycorticosterone acetate (DOCA)-salt hypertensive dogs: comparison with prazosin.

In conscious normotensive and deoxycorticosterone acetate (DOCA)-salt hypertensive dogs, alpha-adrenoceptor antagonistic and antihypertensive actions of SGB-1534, given orally, were compared with those of prazosin. SGB-1534 and prazosin did not markedly influence systemic blood pressure (SBP) and heart rate (HR) in normotensive dogs. These alpha 1-adrenoceptor antagonists inhibited SBP and HR increases induced by i.v. adrenaline in a dose-dependent manner. In DOCA-salt hypertensive dogs, persistent hypotension, accompanied by a reflex tachycardia, occurred after oral administration of SGB-1534 and prazosin. The hypotensive activity of SGB-1534 was much more potent in magnitude and duration than that of prazosin. In isolated canine mesenteric and femoral arteries, SGB-1534, compared to prazosin, elicited a more potent inhibition on the contractile response to a relatively selective alpha 1-adrenoceptor agonist, phenylephrine. It appears that the antihypertensive activity of SGB-1534, like prazosin, is nearly in parallel with its alpha 1-adrenoceptor antagonistic effect.

Adrenergic alpha-Antagonists↗
PubMedDate not supplied

Tissue angiotensin-converting enzyme blockade by MC-838 (altiopril calcium) infused intravenously to miniature pigs: comparison with captopril.

The effect of a new orally active angiotensin-converting enzyme (ACE) inhibitor, calcium(-)-N-[(S)-3-[(N-cyclohexyl-carbonyl-D-alanyl)thio]-2-methyl- prolinate (MC-838, altiopril calcium), on cardiohemodynamics and tissue ACE activity was compared with that of captopril in the anesthetized miniature pig. MC-838 and captopril were infused i.v. for 1 or 3 hr at an equimolar rate of 20 and 10 micrograms/kg.hr-1, respectively. When MC-838 was infused i.v., captopril appeared in approximately 40% of MC-838 in serum, indicating that the amount of serum captopril during the equimolar concentration treatment with MC-838 corresponds to half of serum captopril after the dosing of captopril. During the infusion, the drugs did not significantly affect systemic blood pressure (SBP), heart rate (HR), renal blood flow (RBF) and renal vascular resistance (RVR). MC-838 and captopril, in a similar degree, attenuated the vasoconstrictor response to angiotensin-I (A-I) injected into the renal artery (i.a.), and enhanced the vasodilator one to i.a. bradykinin, 3 hr after the onset of the drug infusion. The animals were sacrificed at 1 and 3 hr after the onset of the infusion of MC-838 or captopril, and the ACE activity in serum and some target organs (lung, kidney, heart, brain and aorta) was determined. Effective activities of MC-838 and captopril occurred in the lung and kidney (only at 3 hr for captopril) where higher ACE activity in a variety of tissues was found, to a lesser degree in the serum (only by captopril) and not at all in the brain, heart and aorta.

Angiotensin-Converting Enzyme Inhibitors↗
PubMedDate not supplied

Antihypertensive action of a novel orally active angiotensin converting enzyme inhibitor altiopril calcium (MC-838) in several hypertensive models of rats: comparison with captopril.

The antihypertensive effects of altiopril calcium (MC-838), calcium(-)-N-[(S)-3-[(N-cyclohexylcarbonyl-D-alanyl)thio]-2-methyl- propionyl]-L-prolinate, a novel inhibitor of angiotensin converting enzyme, compared with captopril, were evaluated in conscious rat models of experimental hypertension. MC-838 (3-30 mg/kg p.o.) as well as captopril (3 and 10 mg/kg p.o.) dose-dependently lowered systemic blood pressure (SBP) with no consistent changes in heart rate (HR) in two-kidney renal hypertensive rats (2 KG-RHRs) and spontaneously hypertensive rats (SHRs). However, MC-838 and captopril, unlike hydralazine, did not significantly produce hypotension in DOCA-salt hypertensive rats. The antihypertensive effect of MC-838, compared with captopril, was characterized by a slower onset and longer duration. When compared on a weight basis of 3 mg/kg, the antihypertensive effect of MC-838 was comparable to that of captopril in magnitude, but the duration of action was approximately 2 times longer than that of captopril. MC-838, like captopril, attenuated angiotensin-I (A-I)-induced pressor response, and augmented bradykinin (BK)-induced depressor one in SHRs. However, no correlation was observed between the modification of the SBP response to exogenous i.v. A-I or BK, and the SBP lowering caused by MC-838 or captopril given orally. In contrast, there was a close correlation between inhibition of lung angiotensin converting enzyme (ACE) (but not plasma ACE) and SBP reduction induced by the 2 ACE inhibitors in SHRs. When administered orally once a day for 9 weeks in 2 KG-RHRs and SHRs, MC-838 dose-dependently reduced SBP throughout the treatment period. After withdrawal of treatment with MC-838 there was no rebound increase in SBP. These studies indicate that MC-838 is a promising antihypertensive agent.

Angiotensin I↗
PubMedDate not supplied

Dural ectasia of the optic nerve sheath in neurofibromatosis type 1: MRI manifestations.

Patients with neurofibromatosis type 1 (NF-1) have an increased incidence of optic glioma. Although spinal dural ectasia or meningocele is well represented in the NF-1 literature, radiologists are not as familiar with dural ectasia of the optic nerve sheath as spinal dural ectasia. This is a report of a pediatric patient with NF-1 with dural ectasia of the optic nerve sheath. This is the second reported case of dural ectasia of the optic nerve sheath demonstrated by magnetic resonance imaging.

Cheek↗
PubMedDate not supplied

Control of epithelial immune-response genes and implications for airway immunity and inflammation.

A major goal of our research is to understand how immune cells (especially T cells) infiltrate the pulmonary airway during host defense and inflammatory disease (especially asthma). In that context, we have proposed that epithelial cells lining the airway provide critical biochemical signals for immune-cell influx and activation and that this epithelial-immune cell interaction is a critical feature of airway inflammation and hyperreactivity. In this brief report, we describe our progress in defining a subset of epithelial immune-response genes the expression of which is coordinated for viral defense both directly in response to replicating virus and indirectly under the control of a specific interferon-gamma signal transduction pathway featuring the Stat1 transcription factor as a critical relay signal between cytoplasm and nucleus. Unexpectedly, the same pathway is also activated during asthmatic airway inflammation in a setting where there is no apparent infection and no increase in interferon-gamma levels. The findings provide the first evidence of an overactive Stat1-dependent gene network in asthmatic airways and a novel molecular link between mucosal immunity and inflammation. The findings also offer the possibility that overactivity of Stat1-dependent genes might augment a subsequent T helper cell (Th1)-type response to virus or might combine with a heightened Th2-type response to allergen to account for more severe exacerbations of asthma.

Animals↗