Recombinant human thyrotropin reduces serum vascular endothelial growth factor levels in patients monitored for thyroid carcinoma even in the absence of thyroid tissue

In this study, we have investigated in vivo the time-dependent effects of TSH on vascular endothelial growth factor (VEGF) production in patients monitored for thyroid carcinoma. Serum VEGF, thyroglobulin (Tg), and TSH levels were assayed at baseline and 6, 24, 30, 48, 72, and 96 h and 1 wk after administration of recombinant human TSH (rhTSH) in 45 thyroidectomized patients affected by differentiated thyroid carcinoma. At baseline, the patients with metastasis (18 cases) showed serum Tg and VEGF values significantly higher than those seen in the cured patients (27 cases). During rhTSH stimulation, the mean VEGF levels decreased significantly in both patient groups. In 60% of patients with metastasis, VEGF nadir occurred at the same time as serum TSH reached the highest values, whereas in 85.7% of the cured patients VEGF decreased after the TSH peak (P = 0.003). In conclusion, we demonstrate for the first time that short-term administration of rhTSH in patients monitored for differentiated thyroid carcinoma induces a significant reduction in serum VEGF values even in the absence of thyroid tissue. This result would suggest that TSH may be able in vivo to regulate VEGF production from tissues other than the thyroid gland.     

Topical methyl nicotinate-induced skin vasodilation in diabetic neuropathy

OBJECTIVE: To evaluate the vasodilation induced by topical application of methyl nicotinate (MN) and to compare it with the vasodilatory response to acetylcholine (ACh) and sodium nitroprusside (SNP) in healthy subjects and diabetic neuropathic patients. RESEARCH DESIGN AND METHODS: Ten diabetic patients with peripheral neuropathy (DN) and 10 age- and sex-matched healthy control subjects (C) were enrolled. The vasodilatory response to topical application of 1% MN and a placebo emulsion at the forearm and dorsum of the foot skin at 5, 15, 30, 60 and 120 min was measured using Laser Doppler Perfusion Imaging. The vasodilatory response to iontophoresis of 1% ACh and 1% SNP solutions was also evaluated. RESULTS: The maximal vasodilatory response to ACh, SNP and MN was similar at the forearm and foot level in the diabetic patients. In the control group, the responses to MN, ACh and SNP were similar on the forearm but in the foot, the MN vasodilatory response was higher when compared to the ACh and SNP responses. MN-related vasodilation was present 5 min after the application, reached its peak at 15-30 min and declined to pre-application levels 120 min afterward. CONCLUSIONS: Topical application of MN at the forearm and foot levels of diabetic neuropathic patients results in skin vasodilation that is comparable to the maximal vasodilation that can be induced by iontophoresis of ACh or SNP and lasts for less than 2 h. Further studies will be required to explore the potential of MN to increase blood flow and to prevent diabetic foot problems in clinical practice.     

P-glycoprotein, lung resistance-related protein and multidrug resistance-associated protein in de novo adult acute lymphoblastic leukaemia

P-glycoprotein (P-gp), lung resistance-related protein (LRP) and multidrug resistance-associated protein (MRP) expression, and blast cell intracellular daunorubicin accumulation (IDA) were evaluated in 95 previously untreated cases of adult acute lymphoblastic leukaemia (ALL) using flow cytometry. Forty-five out of 95 (47%) patients were P-gp positive (+), 12/66 (18%) were LRP+ and 11/66 (17%) were MRP+. Eighteen out of 66 (28%) patients showed a simultaneous multidrug resistance (MDR)-related protein expression higher than controls for more than one protein, while 24/66 (36%) cases did not overexpress any protein. Twenty-one out of 24 (87%) cases overexpressing at least one MDR-related protein had a defect in accumulating daunorubicin into their blast cells, while only 4/24 (16%) cases who did not overexpress any protein had similar features. The complete remission rates were similar in MDR-positive and -negative (-) patients but relapses within 6 months were more frequent in P-gp+ cases, and therefore the disease-free survival duration was shorter in P-gp+ than in P-gp- patients (P = 0.01). The number of MRP+ and/or LRP+ cases was too small to be able to draw any conclusion on their role in affecting or predicting therapy outcome. In conclusion, P-gp overexpression associated with a defect in daunorubicin accumulation is a frequent feature in adult ALL at onset and seems to be related to poorer therapy outcome and, consequently, a shorter disease-free survival. LRP and MRP overexpression seems to be a rare event and no conclusion can be drawn on its prognostic role.     

Genetic haemochromatosis: genes and mutations associated with iron loading

Haemochromatosis is an autosomal recessive disorder common among Caucasians that leads to iron overload. Molecular studies have shown that the disease is prevalently due to a mutation in the HFE gene. Although C282Y in the homozygous state remains the most common patient's genotype, other genes and genetic mutations are associated with haemochromatosis. Haemochromatosis type 2, a severe form with juvenile onset, is due to mutations in an unidentified gene on chromosome 1q. Haemochromatosis type 3 is linked to a locus on 7q22 and is due to mutations in the transferrin receptor 2. Haemochromatosis type 4, the only autosomal dominant form, is caused by mutations in ferroportin 1 on 2q32. The genes responsible for African and neonatal forms of iron overload are still unknown. The identification of all of the genes associated with haemochromatosis is critical for molecular-based diagnosis and central to our understanding of the regulation of iron homeostasis.     

Nonarteritic anterior ischemic optic neuropathy treated with intravenous prostaglandin E1 and steroids

BACKGROUND:

Acute nonarteritic anterior ischemic optic neuropathy (NAION) is considered to be acute ischemia of the posterior ciliary arteries. Prostaglandin E1 (PGE1), a powerful microcirculation vasodilator, has been shown to improve ocular blood flow.

DESIGN:

A nonrandomized, comparative trial.

METHODS:

Eight consecutive cases of NAION were treated with intravenous steroids and PGE1. Seven control cases of NAION were treated with acetylsalicylic acid and oral steroids. Fisher’s exact test was used for statistical analysis.

RESULTS:

The visual acuity improved in seven cases of NAION treated with PGE1 and was unchanged in one. Of the seven control cases, four had no change in vision and three lost further visual acuity on follow-up visits.

CONCLUSIONS:

Intravenous PGE1 and steroids should be considered in cases of NAION to immediately restore blood flow to the optic nerve and improve visual acuity.     

HIV type 1 protease inhibitors enhance bone marrow progenitor cell activity in normal subjects and in HIV type 1-infected patients

HIV-1 protease inhibitors (PIs) may improve hematopoietic functions owing to their direct effects on bone marrow (BM) progenitor cells. In this study we investigated this hypothesis evaluating the effect of adding ritonavir (RTV) and indinavir (IND) on hematopoietic colony formation assays by colony-forming cell (CFC) and long-term culture-initiating cell (LTC-IC) assays, on apoptosis, on cytokine production and stromal cells, in subjects with HIV-1 infection, and in seronegative controls. After PI addition, CFC and LTC-IC assays in HIV-1-infected patients showed levels of colony growth significantly higher than those observed at baseline; the same PI activity on colony formation was observed in healthy subjects. No significant modifications on Fas, the membrane form of Fas (mFas) and Fas-ligand (FasL) expression, and on cytokine production were observed at BM level after the addition of PIs. At baseline, in HIV-1-infected patients, the majority of the stromal cells appeared as large and rounded, whereas after the addition of RTV or IND the stromal cells exhibited a "fibroblast-like" morphology and produced higher stem cell factor (SCF) and lower MIP-1alpha levels when compared with the stromal production without the addition of IND. RTV and IND increased colony growth of BM obtained either from HIV-1-infected patients or from normal individuals, in parallel with the normalization of functional and morphological characteristics of stromal cells.     

Lytic Growth of Human Herpesvirus 8: Morphological Aspects

The human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus, is a gamma herpesvirus associated with AIDS-related body cavity-based lymphomas (BCBL), also called primary effusion lymphomas (PEL). These are a rare form of non-Hodgkin lymphomas in which HHV-8 is present, often associated with Epstein-Barr virus (EBV) infection. HHV-8 is also present in a latent state or in a state of low-level persistence in different primary effusion lymphoma-derived cell lines, such BCBL-1 cells, that lack EBV infection. This cell line was induced to produce mature virions by treatment with 12- O -tetradecanoyl phorbol-13-acetate (TPA) and the characteristic ultrastructural features of HHV-8 lytic replication were identified and compared to those of the other members of Herpesviridae family.