The need of mycophenolic acid monitoring in long-term renal transplants

BACKGROUND: There is little information regarding the 12-h mycophenolic acid (MPA) pharmacokinetics (PK), a way to monitor the drug and the need of frequent monitoring, in stable patients. METHODS: A cohort of 35 adults, under long-term mycophenolate mofetil (MMF) therapy plus cyclosporin A (n = 12), TACimus (n = 12) or MMF only (n = 11); all with prednisone had a 12-h MPA-PK performed to ascertain the percentage of them within a defined therapeutic window. In 13 other patients, two PK studies undergone 1 wk apart were performed to evaluate the need for frequent measurements. RESULTS: Fourteen (40%) patients were within the defined therapeutic window (36-60 microg h/mL). Nine patients (26%) were overexposed while 12 (34%) were underexposed. A Cmax> or =10 microg/mL was seen in 20 (57%) of the patients. These percentages were equally distributed between the treatment groups both for AUC0-12 and Cmax. The equations using C0, C2 or both predict exposure, although the use of C2 seems to be more adequate in clinical practice. There were no differences in MPA exposure in patients with a repeated PK evaluated 1 wk later. CONCLUSION: The use of MMF without monitoring MPA blood levels may cause over-/underexposure to the drug in stable recipients. However, in patients under MMF for more than 1 yr, MPA levels are stable and there is no need for frequent measurements.     

Non-functioning pituitary adenomas: clinical features and immunohistochemistry

Clinically non-functioning pituitary adenomas do not produce clinical signs of hormonal hypersecretion. Therefore, signs and symptoms will depend on the mass effect of these adenomas over the central nervous system. Their etiopathogeny is complex and their development is probably influenced by several factors, such as hypothalamic hormones (GHRH), growth factors (FGF), proliferation factors (PCNA, and KI-67), protein P53 and the proto-oncogene c-erb-B2. OBJECTIVE: 1) Determining the clinical features of a population of 117 patients treated for clinically non-functioning pituitary adenoma (age, sex, tumor size, number of surgical procedures, development of hormonal deficiency and hyperprolactinemia). 2) Identifying, after the patients had been clinically characterized, those with clinically non-functioning adenomas with positive immunohistochemistry for hypophyseal hormones (PRL, LH, FSH, GH, TSH and ACTH). 3) Determining if the immunohistochemistry of this population was positive for the cellular proliferation factor Ki-67, protein P53 and protein C-erb-B2 and establishing a correlation with tumor size and tumor invasiveness. This will help in the evaluation of the prognostic value of these proliferation factors. 4) Confronting the results of immunohistochemistry using a standard block with the results of immunohistochemistry using a tissue micro-array. METHOD: Study of the clinical features of 117 patients with clinically non-functioning pituitary adenoma (age, sex, tumor size, number of surgical procedures, development of hormonal deficiency and hyperprolactinemia). Immunohistochemical study (H&E) of 39 patients for hypophyseal hormones, protein P53, protein C-erb-B2, Ki-67 to establish their correlation to tumor growth. The next step was a tissue micro-array of the 39 previously studied cases, using immunohistochemistry for hypophyseal hormones, protein P 53, protein C-erb-B2, Ki-67 to establish their correlation to tumor growth. RESULTS: There was no statistically significant difference between males and females with regards to age, tumor size and number of surgical procedures (p=0.279, p=813, p=139 respectively). There is a statistically significant correlation between the size of the tumor, the number of surgical procedures and hormonal deficiency (p=0.032, p=0.223 respectively). There was no statistically significant correlation between a positive immunohistochemistry for protein P53, protein C-erb-B2, Ki-67 and tumor size (r=0.182, p=0.396; r=-0.181, p=0.397; r=0.272, p=0.199, respectively). The tissue micro-array also did not demonstrate a correlation between positive immunohistochemistry for Ki-67 and C-erb-B2 and tumor size, but it showed a statistically significant correlation between a positive immunohistochemistry for p53 and tumor size (r=-0.696; p=001). CONCLUSION: The biological behavior of the clinically non-functioning adenoma is similar for both sexes. The larger the tumor the greater the number of surgical procedures needed. Hormonal deficiency also becomes more significant as the size of the tumor increases. This paper suggests that a positive immunohistochemistry for p53 is negatively correlated to tumor size, thus demonstrating that it has a predictor value. However, a positive immunohistochemistry for Ki-67 and protein C-erb-B2 does not seem to be a prognostic factor for clinically non-functioning pituitary adenomas, as is the case with other neoplasias.     

Conjunctival provocation tests in suspected allergic conjunctivitis: a clinical study

We examined 57 patients who showed conjunctivitis suspected of allergic pathogenesis with skin radioallergosorbent (RAST) and conjunctival provocation tests (CPT). Our aim was to define statistical correlations between those tests and their exact values for the right diagnosis. Our data show that CPT is more sensitive than skin tests or RAST to ascertain the origin of conjunctivitis.     

Synchronous Occurrence of Medullary and Papillary Carcinoma of the Thyroid in a Patient with Cutaneous Melanoma: Determination of BRAFV600E in Peripheral Blood and Tissues. Report of a Case and Review of the Literature

The purpose of this study is to describe a case of concurrent medullary and papillary thyroid carcinoma (MTC and PTC) and cutaneous melanoma and to analyze BRAF^V600E mutation in plasma and tissues. We report the clinical history and the laboratory, imaging, and histopathological findings of a 47-year-old man affected by multinodular goiter. BRAF^V600E-mutated DNA was quantified in plasma samples and in cancer sections by quantitative real-time polymerase chain reaction (qPCR). At ultrasound examination, the dominant right nodule of the thyroid was weakly hyperechoic and hypervascularized, while the left one was hypoechoic without internal vascularization. Regional lymphadenomegalia was not detected. Basal plasma calcitonin was elevated, and the patient underwent total thyroidectomy and resection of central cervical lymph nodes. Histopathological examination identified two distinct foci of MTC and PTC and micrometastasis of well-differentiated carcinoma in one of the six resected lymph nodes. RET proto-oncogene germline mutations were not detected. Cutaneous melanoma of the thorax was subsequently diagnosed. BRAF^V600E tissue DNA was detected in PTC and melanoma but not in MTC. The cell-free plasma percentage of BRAF^V600E DNA was detected in pre-thyroidectomy peripheral blood and was drastically reduced after cancer treatments. This study confirms the occurrence of synchronous MTC and PTC and is the first evidence of the co-existence of melanoma and distinct thyroid cancers of different origin. BRAF^V600E allele was detected in PTC and melanoma but not in MTC tissues. BRAF^V600E molecular quantification in pre- and post-treatment blood supports our previous data, suggesting its possible role in diagnosis and follow-up of BRAF-positive tumors.     

Identification and Characterization of Protective T Cells in hsp65 DNA-Vaccinated and Mycobacterium tuberculosis-Infected Mice

Immunization by intramuscular injection of plasmid DNA expressing mycobacterial 65-kDa heat shock protein (hsp65) protects mice against challenge with virulent Mycobacterium tuberculosis H37Rv. During infection or after immunization, CD4⁺/CD8⁻ and CD8⁺/CD4⁻ hsp65-reactive T cells increased equally in spleens. During infection, the majority of these cells were weakly CD44 positive (CD44^lo) and produced interleukin 4 (IL-4) whereas after immunization the majority were highly CD44 positive (CD44^hi) and produced gamma interferon (IFN-γ). In adoptive transfer of protection to naive mice, the total CD8⁺/CD4⁻ cell population purified from spleens of immunized mice was more protective than that from infected mice. When the cells were separated into CD4⁺/CD8⁻ and CD8⁺/CD4⁻ types and then into CD44^hi and CD44^lo types, CD44^lo cells were essentially unable to transfer protection, the most protective CD44^hi cells were CD8⁺/CD4⁻, and those from immunized mice were much more protective than those from infected mice. Thus, whereas the CD44^lo IL-4-producing phenotype prevailed during infection, protection was associated with the CD8⁺/CD44^hi IFN-γ-producing phenotype that predominated after immunization. This conclusion was confirmed and extended by analysis of 16 hsp65-reactive T-cell clones from infected mice and 16 from immunized mice; the most protective clones, in addition, displayed antigen-specific cytotoxicity.

Tuberculosis is a classic example of an infectious disease in which the disease process is caused by the immune response directed at the infectious agent. The bacteria and their products are, in themselves, not very toxic, and the extensive tissue damage, wasting, and death of the diseased individual largely constitute the immunopathology of the cell-mediated immune response. Nevertheless, it is also the cell-mediated response that protects against the disease by arresting, killing, and removing the multiplying bacteria. Whether this protective effect occurs early or late, and temporarily or permanently, determines disease progression by regulating the supply of antigen that drives the immunopathology. An important question that arises from this balance between the protective and harmful effects of the immune response is whether the antigens and immune responses that protect can be distinguished from those that harm. If so, they might be separately manipulated in new vaccines or in immunotherapy of the disease.The T lymphocytes that regulate cellular immunity can be divided not only into the CD4⁺/CD8⁻ and CD8⁺/CD4⁻ phenotypes that primarily recognize exogenous and endogenous antigens, respectively (8), or into activated (memory) and nonactivated cells according to highly CD44-positive (CD44^hi) and weakly CD44-positive (CD44^lo) expression (5) but also into two major functionally distinct types on the basis of the profiles of cytokines that they produce. Type 1 cells (Th1 or TC1) favor development of cellular immunity (typified by gamma interferon [IFN-γ], interleukin 2 [IL-2], and IL-12 production). Type 2 cells (Th2 or TC2) favor development of antibody response (typified by IL-4, IL-6, and IL-10 production). Each type promotes differentiation of precursors into the same phenotype and inhibits development of the other phenotype (2, 27), and in consequence the type of response initiated in a microenvironment tends to be self-sustaining. IFN-γ is essential for the development of protective immunity (38) and is probably the most important factor that activates macrophages for antimycobacterial action, at least in mice (13, 34, 35). Therefore protection would be expected to be associated with an immune response in which the type 1 cytokine profile predominated. We have found that immunization procedures that present mycobacterial hsp65 to the immune system as an endogenous antigen generate strong protection against tuberculosis challenge and that this is associated with the presence of a splenic T-cell population in which CD8⁺/CD44^hi IFN-γ-producing cytotoxic cells are prominent (28a). However, cells with a type 2 profile are also present in substantial numbers following infection (22, 39) or Mycobacterium bovis BCG vaccination (24), and the question of what contribution the other phenotypes make to protection arises. To help to answer this question we have used here the combined approaches of comparing the frequency of the different phenotypes in spleens of hsp65 DNA-vaccinated and Mycobacterium tuberculosis-infected mice and testing the different phenotypes, either as purified subpopulations or as T-cell clones, in adoptive transfer of protection.     

Triphenyltin hydroxide induces changes in the oxidative stress parameters of fish

Among all organotin compounds , triphenyltin hydroxide (TPhTH) is widely used as fungicide and moluscicide in Brazil. However, the effects of TPhTH on the biochemical parameters of non-target organisms, such as fish, are little known. The aim of the present study is to assess the possible toxic effects of different concentrations of waterborne TPhTH on silver catfish belonging to species Rhamdia quelen. The fish were exposed to two different concentrations of TPhTH (1.08 and 1.70?µg/L as Sn) for 15 days and then compared to the control group (triplicate, n?=?3). The antioxidant profile (catalase (CAT) and the glutathione S-transferase (GST)) and the oxidative stress parameters (TBARS—thiobarbituric acid-reactive substances and protein carbonyl (PC)) were set after the exposure to TPhTH. The TBARS level and the PC content increased in several organs of the Rhamdia quelen (brain, liver, muscle and gills) under the two concentrations of TPhTH in comparison to the control group. The CAT activity in the liver and gills has enhanced in all tested TPhTH concentrations. The GST activity increased in the brain, liver and muscle tissues under all the TPhTH concentrations. The significant changes in the biomarkers indicated that the investigated pesticide could have harmful effect on fish, in the field. However, these biomarkers were measured after the fish received doses lower than the recommended for use in agriculture.