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Biomedical subjects

H Ratech

Publications and source records attributed to H Ratech.

48 records · Page 3Linked to original sources
PubMed1984

Effects of deoxycoformycin in mice. I. Suppression and enhancement of in vivo antibody responses to thymus-dependent and -independent antigens.

The effect of 2'-deoxycoformycin (DCF) on the PFC responses of AKR mice to SE, TNP-Ficoll, and TNP-B. abortus was examined. Subcutaneous injection of DCF 4 days before antigen caused suppression of all three responses by 70 to 78%. In contrast, injection of DCF 1 day after antigen caused enhancement of both the anti-SE and the anti-TNP-Ficoll responses. Although a single high dose of cortisone acetate injected 4 days before antigen caused a similar suppression, the effect of DCF was not mediated via a steroid release, inasmuch as DCF also suppressed the immune response in adrenalectomized mice. The response of BALB/c mice to TNP-Ficoll was also inhibited by DCF pretreatment and enhanced by injection of DCF after antigen. In contrast, in athymic mice DCF caused suppression of the anti-TNP-Ficoll PFC response, whether injected before or after antigen. These results are interpreted as suggesting that DCF causes suppression primarily via an effect on B cells. The enhancement seen in normal but not in athymic mice may possibly be ascribed to an effect on suppressor T cells. Apparently the enhancement of both TD and TI responses caused by DCF injected 1 day after antigen in normal mice is the net result of these two opposing effects. The results imply that helper T cells are resistant to DCF.

Adrenalectomy↗
PubMed1982

Pathologic predictors of recurrence in stage 1 (TINOMO) breast cancer.

A group of 122 consecutively treated pathologic Stage 1 (TINOMO) patients with cancer of the breast were studied to define histopathologic predictors of recurrence. Lymphatic invasion was the most significant predictor of recurrence; recurrence was present in 32% (8/25) of patients who had lymphatic invasion and in 10.3% (10/97) of patients who did not (P = 0.006). Histologic type was also predictive of recurrent disease. Eighteen per cent (18/101) of patients with invasive ductal or lobular carcinoma developed recurrent disease, while none of the group of 21 patients with medullary carcinoma, tubular carcinoma, colloid carcinoma, Paget's disease, and intraductal carcinoma with minimal invasion suffered a recurrence (P = 0.036). Vascular invasion, grade of malignancy, cellularity, presence or absence of circumscription, cellular infiltrate, fibroblastic response, neural invasion, and necrosis were not significant predictors of recurrence. Multiple logistic regression analysis of patients with invasive ductal or lobular carcinoma confirmed the results for individual factors, that only patients with lymphatic invasion were at higher risk of recurrence.

Breast Neoplasms↗
PubMed1982

Increased excretion of modified adenine nucleosides by children with adenosine deaminase deficiency.

We have identified seven adenine nucleosides in urines of untreated adenosine deaminase (ADA) deficient patients, four of which (adenosine, 2'-deoxyadenosine, 1-methyladenosine and N6-methyladenosine) have been previously identified in urines of normals and/or ADA deficient patients. We confirm that ADA deficient patients excrete markedly increased amounts of 2'-deoxyadenosine (582 +/- 363 versus normal of less than 0.1 nmoles/mg creatinine) and increased amounts of adenosine (29.4 +/- 5.7 versus normal of 4.12 +/- 1.0 nmoles/mg creatinine). We have found three modified adenine nucleosides previously undetected in human urine. These three compounds are 2'-O-methyladenosine, N6, 2'-O-dimethyladenosine and an as yet incompletely characterized modified adenine nucleoside, R-adenosine. Only ADA deficient patients excrete detectable amounts of 2'-O-methyladenosine (2.1 +/- 1.1 versus normal of less than 0.1 nmoles/ mg creatinine), whereas both normals and ADA deficient children excrete N6, 2'-O-dimethyladenosine and R-adenosine. However, ADA deficient patients do excrete increased amounts of R-adenosine (5.5 +/- 1.0 versus normal of 1.4 +/- 0.4 nmoles/mg creatinine).

Adenine Nucleotides↗
PubMed1982

Uterine leiomyomas, serum cholesterol, and oral contraceptives. A preliminary study of epidemiologic differences in Los Angeles, California and Albany, New York.

In order to determine the feasibility of a large-scale study to investigate the relationship of serum cholesterol levels to the presence or absence of uterine leiomyomas, the medical records of 67 women aged from 30 to 39 who underwent hysterectomies at UCLA Hospital, Los Angeles, and Albany Medical Center, Albany, New York were reviewed. The women at UCLA were more likely to have a history of oral contraceptive use than were the women in Albany; they also had higher serum cholesterol values. In both hospitals, increasing age was associated with the presence of leiomyomas, and oral contraceptive use was associated with absence of pathology in the resected uterus. In Albany, but not in Los Angeles, oral contraceptive uterus. In Albany, but not in Los Angeles, oral contraceptive use was associated with elevated serum cholesterol, As expected, uterine weight and presence of leiomyomas were strongly associated. It was concluded that serum cholesterol levels were apparently unrelated to presence of uterine leiomyomas and to uterine weight in this group of women. Recommendations are made for the design of a case-control study to further investigate both the cholesterol-leiomyoma relationship and the other results reported here.

Adult↗
PubMed1981

Comparison and possible homology of isozymes of adenosine deaminase in Aves and humans.

Two kinetically distinct adenosine deaminase (ADA) isozymes with different molecular weights (35,000 and 100,000 daltons) are found in chicken liver in approximately equal amounts. The 100,000-dalton ADA has a markedly higher Km for adenosine and a markedly lower deaminating activity for deoxyadenosine relative to adenosine than does the 35,000-dalton ADA. A 100,000-dalton ADA isozyme has only recently been detected in mammalian tissues, where, in contrast to the chicken, it is only a trace component of total ADA activity. The human 100,000-dalton ADA isozyme, compared to the human 35,000-dalton ADA isozyme, has been reported to have a higher Km, a lower pH optimum, and a greater resistance to inhibition by erythro-9-(2-hydroxy-2-nonyl) adenine (EHNA). The similarity in KmS of the 100,000-dalton ADA isozyme in man and aves led us to hypothesize that these isozymes might be descended from a common ancestor and therefore also be similar as to other kinetic parameters. We now report that the chicken 100,000-dalton ADA, like the human 100,000-dalton isozyme, has a lower pH optimum and a greater resistance to inhibition by EHNA than does the avian or human 35,000-dalton isozyme. In addition, the avian 100,000-dalton isozyme is relatively resistant to inhibition by deoxycoformycin and has a cathodal rather than an anodal electrophoretic mobility at pH 6.5. Conversely, we report that the human 100,000-dalton ADA isozyme, similar to the avian 100,000-dalton ADA, has markedly lower relative deaminating activity for deoxyadenosine than does the 35,000-dalton ADA human isozyme. Thus, despite the marked difference in the relative amount of the 100,000- and 35,000-dalton ADA isozymes in man as compared to aves, the 100,000-dalton ADA isozymes from both species exhibit several similar kinetic properties, all of which are different from those of the 35,000-dalton ADA isozymes. We also report using a new sensitive assay, relative rates of degradation by the two chicken isozymes of several naturally occurring modified adenine nucleosides which are inhibitory to in vitro human lymphocyte proliferation.

Adenosine Deaminase↗
PubMedDate not supplied

Lymph node manifestations of limited Churg-Strauss syndrome.

Churg-Strauss syndrome is a systemic vasculitis characterized by asthma, tissue and blood eosinophilia, and granulomatous vasculitis. Lymph node involvement as part of systemic disease or as the primary site of involvement is rare. We report a single case of primary (isolated) nodal Churg-Strauss syndrome occurring in an 11-year-old boy with asthma, fever, night sweats, and cervical adenopathy. The clinical diagnosis was lymphoma. The unusual presentation of Churg-Strauss syndrome limited to lymph nodes is important to recognize and diagnose correctly because the administration of steroid therapy is associated with a favorable outcome.

Child↗
PubMedDate not supplied

Non-Hodgkin's lymphoma in women with breast cancer.

PURPOSE: The purpose of this study was to describe a series of patients with breast cancer and non-Hodgkin's lymphoma and to determine the usual sequence of the diagnoses. Therapy for both neoplasms and its relationship to the development of the second neoplasm were also evaluated. PATIENTS AND METHODS: Patients were identified primarily from cancer registries at various institutions. The observed proportion of women diagnosed with breast cancer first, after, or simultaneously with non-Hodgkin's lymphoma was compared with the expected proportion by employing New York State and Surveillance, Epidemiology, and End Results program cancer incidence rates. RESULTS: The expected number of lymphoma cases that were diagnosed after or simultaneously with breast cancer was 31.6 (New York state data) to 39.1 (New York State and Surveillance, Epidemiology, and End Results data), and 78 such cases were identified from a total group of 87 (P < or = .001). There was no evidence that in this study, lymphoma as a second neoplasm was therapy induced. DISCUSSION: Anecdotal case reports suggest a relationship between breast cancer and non-Hodgkin's lymphoma. Mouse mammary tumor virus induces breast cancer and, in some circumstances, lymphoma in mice. The mouse mammary tumor virus ENV gene has been identified in approximately one third of human breast cancers. Women with both breast cancer and lymphoma are diagnosed first with breast cancer or simultaneously with both cancers more frequently than expected, and the lymphoma is not therapy induced. In some women with both breast cancer and lymphoma, the two neoplasms may have a common etiology, perhaps viral.

Adult↗