Morphological Investigation of Cavity Formation in Articular Cartilage Induced by Oiloxacin in Rats

Morphological Investigation of Cavity Formation in ArticularCartilage Induced by Ofloxacin in Rats. Kato, M., andOnodera,T.( 1988).Fundam. Appl Toxwol. 11, 110–119. Ofloxacin,a quinolone antibacterial agent, induced blisters and/or erosionsin the articular cartilage of the humeral trochlea, femoralcondyle, and femoral head of immature rats. Histologically,cavity formation was seen in the middle zone of the articularcartilage. Changes were detected as early as 5 hr after a singleoral administration of 1000 or 3000 mg/kg. These changes werecharacterized by condensation, atrophy, and deformation of thenuclei of chondrocytes distributed in the middle zone. In suchnuclei, aggregation of heterochromatin was observed. Degeneratedcells with vacuolated and partially disintegrated cytoplasmswere also seen in this zone. These lesions were followed byedema of the matrix accompanied with markedly decreased stainabilitywith safranin-O, and a cavity was formed later by liquefactionof the cartilage. The changes were reversible, with reboundingoccurring even with continued treatment with ofloxacin. Theproliferation of chondrocytes around the lesion chiefly contributedto the repair. Ofloxacin had no adverse effects on the articularcartilage in rats when treatment was initiated at 8 weeks ofage or later.     

Potentiations of N-Methylcarbamate Toxicities by Organophosphorus Insecticides in Male Mice

Potentiations of N-Methylcarbamate Toxicities by OrganophosphorusInsecticides in Male Mice. TAKAHASHI, H., KATO, A., YAMASHITA,E., NAITO, Y., TSUDA, S., and SHIRASU, Y. (1987). Fundam. Appl.Toxicol. 8, 139–146. A N-methylcarbamate insecticide,2-sec-butylphe-nyl N-methylcarbamate (BPMC), is markedly potentiatedby low-dose treatments of P=S type organophosphorus insecticides.As a mechanism of this potentiation, the increase of plasmaBPMC concentrations due to the inhibited metabolic degradationhas been suggested. In this study, acute toxicities of fiveN-methylcarbamates structurally related to BPMC were studiedafter low-dose treatments of three P=S type organophosphorusinsecticides (cyanophos, feni-trothion, and malathion) and oneP=O type organophosphorus insecticide (dichlorvos), and therole of plasma concentrations of N-methylcarbamates in the potentiationswas examined. Acute toxicities of five N-methylcarbamates werepotentiated by the treatments of the P=S types, among whichthe potentiation of BPMC was strongest. BPMC toxicity was notpotentiated by the treatment of the P=O type. Plasma concentrationsof BPMC were increased by the treatments of the P=S types, butnot by the treatment of the P=O type. The acute toxicity andplasma concentrations of BPMC were increased by SKF 525-A (aninhibitor of mixed-function oxidase). These results suggestthat the increase of plasma BPMC concentrations may be relatedto the potentiation of BPMC toxicity. The treatment of fenitrothionincreased plasma concentrations of other N-methylcarbamatesmore than those of BPMC, although the potentiation of BPMC toxicitywas strongest. SKF 525-A and fenitrothion treatments increasedplasma BPMC concentrations to a similar degree, but the potentiationof BPMC toxicity by SKF 525-A was significantly less than thatby fenitrothion. Thus, some other mechanism(s) may be responsiblefor the potentiations of the N-methylcarbamate toxicities.     

Natural Killer (NK) and Lymphokine-Activated Killer (LAK) Cell Activity in Healthy Volunteers with Special Emphasis on the Familial Incidence of Cancer

Natural killer (NK) and lymphokine activated killer (LAK) cellactivities in 133 healthy volunteers were analyzed with regardto the volunteer's sex, age, smoking history and the familialincidence of cancer. None of these factors had any influence on NK and LAK cell activities.It was concluded that identifying individuals with increasedrisk of cancer development by examining NK and LAK activitieswould be difficult.     

Immunohistochemical evidence of insulin-like growth factor II in human small hepatocellular carcinoma with hepatitis C virus infection: Relationship to fatty change in carcinoma cells

It has recently been reported that insulin-like growth factor II (IGF-II) may play a role in the pathogenesis of hepatocellular carcinoma (HCC). We studied the relationship between the expression of IGF-II and fatty change in human small HCC using immunohistochemical staining techniques. Liver biopsy specimens were obtained from 35 patients with HCC (consisting of 15 patients with fatty change and 20 patients without fatty change). All patients had serum markers for the hepatitis C virus (HCV) and histological findings obtained from non-tumourous lesions showed liver cirrhosis or chronic active hepatitis. Immunohistochemical staining was performed using a monoclonal antibody against rat IGF-II. A positive immunoreaction was found in 69% (24/35) of HCC. Insulin-like growth factor II was immunodetected in 80% (12/15) of HCC with fatty change but only in 60% (12/20) of those without fatty change. In most cases, IGF-II was not found in hepatocytes from non-tumourous lesions. We believe this to be the first time that IGF-II has been detected immunohistochemically in small HCC derived from HCV infection. This growth factor was more frequently immunodetected in HCC with fatty change than without. As insulin is an essential factor for the metabolism of fatty acids, IGF-II may play an important role in both fatty degeneration and in the proliferation of HCC cells. Furthermore, immunohistochemical IGF-II staining may contribute to the diagnosis of HCC, particularly in early stages accompanied by fatty change.     

Immunotherapy Affects the Seasonal Increase in Specific IgE and Interleukin-4 in Serum of Patients with Seasonal Allergic Rhinitis

This study was designed to determine seasonal changes in cytokines, soluble CD23 and specific IgE in the serum of patients with seasonal allergic rhinitis, and the effect of immunotherapy on these seasonal changes. Fifty-four patients with seasonal allergic rhinitis caused by Japanese cedar pollens were divided into a medication group and an immunotherapy group. The patients of the medication group were treated with non-sedating antihistamines alone during the pollen season. The patients of the immunotherapy group had been treated for variable periods (mean, 5.0 ± 3.2 years) with immunotherapy using Japanese cedar pollen antigens. Serum samples were collected before and during the pollen season from each patient, to determine specific IgE, interleukin-4 (IL-4), interferon-γ (IFN-γ) and soluble CD23 levels in serum. A significant increase in specific IgE and IL-4 and a significant decrease in IFN-γ were observed during the pollen season in the medication group. In contrast, in the immunotherapy group, none of specific IgE, IL-4 and IFN-γ was significantly changed following natural exposure to pollens. However, these effects were not significant in patients undergoing immunotherapy for 3 or fewer years. Seasonal rates of increase in specific IgE and IL-4 differed significantly between good responders and poor responders to immunotherapy, but seasonal rates of decrease in IFN-γ did not. A seasonal rate of increase in soluble CD23 was significantly correlated with a seasonal rate of increase in specific IgE, in both the medication and the immunotherapy groups. The seasonal rate of increase in soluble CD23 was significantly smaller in the good responders than in the poor responders to immunotherapy. In conclusion, pollen immunotherapy reduces the seasonal increase in specific IgE, IL-4 and soluble CD23 in serum, and in addition switches the seasonal preferential activation of Th-2 cells to reciprocal activation of Th-1 cells with treatment over several years. It is likely that the mechanisms responsible for the clinically beneficial effects of immunotherapy principally involve the modulation of Th-2 rather than Th-1 cytokines.     

Mexiletine and Propafenone: A Comparative Study of Monotherapy, Low, and Full Dose Combination Therapy

The electrophysiological effects of combination therapy of mexiletine and propafenone were assessed using standard 12-Iead electrocardiogram (standard ECG), signal-averaged EGG (SAECG), and ambulatory ECG in 31 patients with ventricular arrhythmias. All patients underwent mexiletine monotherapy (M-mono), propafenone monotherapy (P-mono), low dose combination therapy (low M 4- P), and full dose combination therapy (full M + P). Full M + P increased the PQ interval and QRS duration to the same extent as P-mono did. Low M + P increased PQ interval and QRS duration to a lesser extent than P-mono and full M + P did. P-mono and full M + P significantly decreased root mean square (RMS) and increased f-QRS in SAECG, while M-mono and low M + P showed only a weak trend. SAECGs with late potentials increased in number with treatments; 9 in predrug control, 11 on M-mono, 15 on P-mono, 10 on low M + P, and 14 on full M + P. The percent suppression of frequent premature ventricular contractions (PVCs) (> 1,000/day) with M-mono, P-mono, low M + P, and full M + P were 46.4 ± 9.0,56.6 ± 10.4,64.4 ± 9.2, and 71.4 ± 7.1, respectively, and those of frequent couplets (> 10/day) were 58.3 ± 17.7, 62.6 ± 23.6, 87.5 ± 6.2, and 92.1 ± 4.0, respectively. Thus, full dose combination of mexiletine and propafenone exhibited the maximum antiarrhythmic efficacy without enhancement of effects on standard ECG and SAECG. Low dose combination therapy showed better antiarrhythmic efficacy in association with lesser effects on standard ECG and SAECG compared with propafenone monotherapy.     

Anatomical and histological studies of so-called Müllerian duct cyst

BACKGROUND: We examined so-called Müllerian duct cysts both histologically and immunohistochemically with anatomical observation to investigate the etiology of the 'Müllerian duct cyst'. METHODS: Five cystic lesions located in the prostatic midline were obtained from surgical specimens. A communication between the cystic lesion and the urethra via the utricular orifice was looked for and the specimens were subjected to histological and immunohistochemical testing. RESULTS: A communication between the cyst and the urethra was confirmed in four cases, but not in one case. Histological and immunohistochemical examinations of the epithelium lining indicated that its characteristics were identical to those of the prostatic utricle in all cases. CONCLUSIONS: The so-called Müllerian duct cyst exhibits features comparable to those previously described in the prostatic utricle. There is no evidence that these cystic lesions originate from the Müllerian duct remnant, at least in the epithelial lining. We suggest that they should be termed a prostatic utricular cyst or cystic dilation of the prostatic utricle, depending on whether an outlet to the urethra is absent or present, respectively.     

Posttraumatic symptoms among victims of the Great Hanshin–Awaji Earthquake in Japan

Two comparative studies conducted in the early and reconstruction stages following the 1995 Hanshin–Awaji earthquake in Japan are presented. In the first study, posttraumatic symptoms among younger evacuees (<60 years) were compared with the symptoms among the elderly evacuees (≥ 60 years) in the same shelter. In the first study, though most of the symptoms remained unchanged among the younger subjects from the time of the third-week assessment to that of the eighth week, the symptoms improved among the elderly subjects. In the second study, the psychological effects of those who were living in temporary housing and those who were not were compared during the reconstruction stage. That study demonstrated that the temporary housing residents had high exposure to the traumatic event, poor socioeconomic status, and various secondary stressors. The result of these factors is that they have a higher chance of facing various types of mental health problems. By examining the data obtained from these studies, the characteristics of psychological distress and coping among survivors at the different stages after the earthquake, and matters of future concern relating to the kind of mental health care required at each stage, are discussed.     

Large intestinal type-urachal adenocarcinoma with focal expression of prostatic specific antigen

We present a case of colonic-type adenocarcinoma, which might arise from an urachal remnant through a villous adenoma. The cancer tissue in the present case showed focal immunoreaction to prostate-specific antigen (PSA). This is the first report of urachal adenocarcinoma expressing PSA.