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We report a case of human anaplasmosis (HA) fulfilling the confirmation criteria: epidemiologic data and clinical picture compatible with HA; presence of a morulae within polymorphonuclear leukocyte; and positive PCR assay for Anaplasma phagocytophilum: This case report shows the presence of HA in Spain.
OBJECTIVE: All-trans-retinoic acid (ATRA) promotes cell differentiation. We have studied its effect on the local recurrence and metastatic spreading of an experimental rhabdomyosarcoma in rats. DESIGN: syngenic rhabdomyosarcoma cells (S4MH) were inoculated s.c. in male WAG/RijCrl rats. After 25 days tumors were excised and a 40% hepatectomy was performed for all animals. Ten days later the rats were sacrificed and a thorough necropsy was performed. The animals were randomly allocated to receive daily doses of ATRA (5 mg/kg, i.p.) or its solvent (Clinoleic/ethanol 90/10), starting three days before surgery until the end of the experiment. RESULTS: ATRA reduced the incidence of local recurrence from 70 to 33% (p < 0.05), but the tumor size was not altered (1.8 vs. 2.0 cc). Regarding inguinal metastasis, there was a six-fold decrease (0.2 vs. 1.2 cc; p < 0.05) in mean tumor volume, although the rate of this proliferation increased sharply (86 vs. 29%; p < 0.05) for treated animals. The volume of the retroperitoneal tumor masses also decreased with ATRA (0.7 vs. 5.1 cc; p < 0.05), but the difference in rate was not significant (71 vs. 67%). Lung metastases, which were present in 100% of control animals, were found in only 33% of treated rats, while the mean number of metastatic foci dropped from 26.7 to 5.7 (p < 0.05). CONCLUSION: Protocols including retinoid administration prior to and following primary tumor excision could help in controlling both recurrence and metastatic progression in surgically treated rhabdomyosarcoma.
INTRODUCTION: Severe episodes of steroid-refractory ulcerative colitis (UC) were considered an indication for surgery until the introduction of new immunosuppressive agents such as cyclosporine. OBJECTIVES: 1) To confirm the efficacy of intravenous cyclosporine in inducing remission in severe episodes of steroid-refractory UC; 2) To analyze the efficacy of triple immunosuppressive therapy with cyclosporine, azathioprine and prednisone in the maintenance of remission induced by intravenous cyclosporine. PATIENTS AND METHOD: Fourteen patients diagnosed with a severe episode of steroid-refractory UC were treated with intravenous cyclosporine at a dose of 4 mg/kg/day. In all patients, after response was induced, this regimen was substituted by oral cyclosporine plus azathioprine at a dose of 2-2.5 mg/kg/day and decreasing doses of corticoids. Neoral cyclosporine was progressively reduced until discontinuation within 3 months, coinciding with a simultaneous decrease of oral steroids. RESULTS: All patients showed response to intravenous cyclosporine with a significant reduction in the Truelove index calculated before and after treatment. After remission was induced, all patients followed triple immunosuppressive therapy for 3 months. In the follow-up for a mean of 24 months (range: 14-34) only two patients required admission for a new episode of UC and colectomy was finally indicated in only one. None of the 14 patients treated with cyclosporine showed severe adverse effects attributable to the drug. CONCLUSIONS: Intravenous cyclosporine is a safe and effective alternative in the treatment of severe episodes of steroid-refractory UC. Early initiation of oral administration associated with azathioprine is useful in maintaining response, reducing subsequent relapses and the need for colectomy during the follow-up of these patients.
In the early stages of metastasis, development of the disease is dependent on growth factors produced by the host. There are clinical situations associated with an increase in these factors, such as partial resection of metastasized liver. Given the important role of hepatotrophic factors in liver regeneration, we have studied the effect of partial hepatectomy on the development of residual micrometastases in the liver, and on the neoplastic process as a whole. We used a murine model in which a rabdomiosarcoma was established by subcutaneous inoculation of syngeneic tumor cells in male Wag rats. Subsequently, the primary tumor was resected and/or a 40% hepatectomy was performed. The effect of these two surgical procedures on the tumor process was analyzed on the 25th and 35th days post-inoculation, and the percentage of regenerating hepatocytes was assessed. Both the tumorectomy and liver resection, when not combined, produced an increase in regional adenopathies without modifying the evolution of metastasis in the liver. However, when tumor excision and partial hepatectomy were performed simultaneously, there was a net increase in the metastatic process. In addition to a rapid spread of the disease (lung, mediastinum, retroperitoneum), the number of liver metastases increased by 300%. This development coincided with a steep rise in the percentage of regenerating hepatocytes, which nearly doubled that of the group subjected only to liver resection. We conclude that liver resection, alone or combined with excision of the primary tumor, may enhance tumor progression, both locally and at the metastasic level.
The efficacy of sequential chemoimmunotherapy involving interleukin-2 (IL2) in metastatic melanoma is limited, in part, by the severe toxicity associated with most therapeutic regimens. Glutathione (GSH), the most prevalent intracellular non-protein thiol, plays an important role in protecting against cellular injury caused by various anticancer agents. GSH is also involved in the IL2-induced proliferative activity of immune system cells and some melanoma cells expressing IL2 receptors, such as B16 melanoma cells. The present study investigated the effect of selective manipulation of GSH using the cysteine prodrug l-2-oxothiazolidine-4-carboxylate (OTZ) on the response of B16 melanoma to sequential biochemotherapy with cyclophosphamide (CY) and IL2. We found that OTZ, by depressing GSH levels, abrogates the in vitro growth-promoting effects of IL2 on B16 melanoma cells. The combination of OTZ plus IL2 in vivo also showed antitumour activity in mice bearing B16 melanoma liver metastases, significantly increasing their life span. Schedule dependency between both compounds was found; OTZ given intermittently in combination with daily IL2 administration was found to be the best therapeutic schedule. We also observed that whereas IL2 or OTZ alone added to CY resulted in a lower or non-significant improvement in the life span of the mice compared with tolerated doses of CY alone, the addition of both OTZ and IL2 to CY produced a significantly greater increase in survival than CY alone, and markedly protected mice against CY-induced toxicity, which allowed the administration of otherwise lethal doses of CY, with the CY activity/toxicity ratio being increased by four-fold.
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Male OF1 strain mice were allocated, after 2 weeks of individual housing, to cohabitating (6 or 16 days), fixed dyadic interaction pairs (6 or 16 daily encounters) or control groups (6 or 16 days). These different social stress situations were assessed for their effects on splenic contents of NE, IL-1 and IL-2 and serum levels of corticosterone. Spleen NE contents showed no significant variations, but serum corticosterone titers were generally higher in interacting pairs and subordinates. Splenic IL-2 did not respond in the same way to the treatments as IL-1. The differences in splenic interleukin contents could not be simply related to observed changes in serum corticosterone levels. Different mechanisms appear to regulate changes in glucocorticoids and the measured cytokines. These physiological phenomena do not simply reflect in the animal's social status (dominant or submissive). The intensity and duration of the agonistic behavior displayed as well as the interaction experience accumulated may account for the observed differences between the paradigms.
AIMS: To analyze the prevalence of patients with chronic liver disease associated with hepatitis C virus (HCV) not undergoing antiviral treatment and the reasons for which this treatment was not indicated. PATIENTS AND METHODS: 718 patients with HCV infection referred for therapeutic evaluation between January 1990 and January 1998. Demographic, clinical, biological and histological variables were prospectively analyzed. The patients were divided into two groups: treated and untreated. RESULTS: 393 patients were treated and in 325 patients antiviral treatment was not considered to be indicated. The most frequent reasons for not starting therapy were advanced age, the presence of decompensated cirrhosis and the patients' refusal to undergo antiviral treatment. CONCLUSIONS: A broad subgroup of patients with chronic liver disease associated with HCV do not receive antiviral treatment. This is related with: a) patients' advanced age at diagnosis, b) diagnosis at the advanced stages of the disease, and c) patients' refusal to undergo such treatment after being informed of its potential risks and benefits.
OBJECTIVES: Dendroaspis natriuretic peptide (DNP) is a novel peptide that is structurally similar to atrial, brain, and C-type natriuretic peptides. Many natriuretic peptides are increased in hepatic cirrhosis, but the role of DNP in cirrhosis is unknown at present. The aim of the study was to investigate plasma levels of dendroaspis natriuretic-like immunoreactivity in cirrhosis. METHODS: We measured plasma concentrations of DNP by radioimmunoassay methods in 12 cirrhotic patients without ascites and 44 cirrhotic patients with ascites, and compared these values with 20 age-matched healthy subjects. Renal function, plasma cGMP concentration, plasma renin activity, and plasma endothelin concentration were measured in each patient. RESULTS: Patients without ascites had circulating levels of DNP similar to those of healthy subjects. By contrast, patients with ascites had increased circulating DNP levels compared to both patients without ascites and healthy subjects. In addition, circulating levels of DNP increased in relation to the severity of cirrhosis. Significant positive correlations were also found between DNP levels, endothelin concentrations, and plasma renin activity. CONCLUSIONS: The results of this study indicate that plasma DNP is increased in cirrhotic patients with ascites.
The interaction of vanadate with the ligand 1,2-dimethyl-3-hydroxy-4-pyridinone (Hdmpp) was studied in aqueous solution using a combination of multinuclear NMR and EPR spectroscopies, as well as potentiometry and cyclic voltammetry. The different species in solution were identified and characterized, and their pKa values and stability constants determined. The vanadium complexes formed in solution are strongly dependent on media composition (ionic strength, presence of buffer), pH and metal-to-ligand ratio (M:L). Two major species--V(V)/dmpp and V(V)/(dmpp)2--are formed in a 140 mM NaCl solution within the pH range 4.5 to 9.0, when M:L = 1:2. In the presence of excess ligand (M:L < or = 1:5), only the 1:2 complex is present, and at pH < 4 paramagnetic species are detected by EPR in solution, thus indicating a reducing capacity of the ligand. Cyclic voltammetry shows that redox processes in solution are not just electron transfer, but are accompanied by chemical reactions. The pK, values and stability constants were determined both by 51V NMR spectroscopy and potentiometry. The present results have a particular interest in the understanding of the aqueous solution chemistry in aerobic conditions of bis(1,2-dimethyl-3-hydroxy-4-pyridinonato) oxovanadium(IV) complex, VO(dmpp)2, a vanadium compound with potential insulin-mimetic properties.
BACKGROUND: Inducible adhesion molecules are involved in cell-mediated allograft rejection. In addition, the endothelium is the main target of this process. This study investigated, whether soluble (s) forms of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) are elevated during cellular rejection and whether hyaluran is a useful marker of endothelial function in liver transplantation. METHODS: Serum levels of sICAM-1, sVCAM-1, and hyaluran were determined in 24 controls and 27 hepatic transplant recipients. These patients were divided in two groups: group I, 14 patients without rejection; and group II, 13 patients with rejection. Samples were collected on day 1 and 7 after transplantation, on the day of liver biopsy, and after treatment of the rejection. RESULTS: We found a significant increase in sICAM-1 levels in the postoperative period in the rejection group compared with the non rejection group. It persisted significantly elevated until the diagnosis of rejection was made. In contrast, sVCAM-1 was only significantly elevated in the rejection group when diagnosis of rejection was evident. Hyaluran levels were also significantly elevated in the rejection group at diagnosis of rejection. We noticed a significant decline in sICAM-1, sVCAM-1, and hyaluran levels after successful treatment of rejection. In addition, we observed in the non-rejection group a stable lower levels of hyaluran during the entire postoperative period. CONCLUSIONS: The release of circulating adhesion molecules is a prominent feature coinciding with the first episode of hepatic rejection. Differential patterns of sICAM-1 and sVCAM-1 exist during rejection. In addition, hyaluran levels may be a sensitive marker of liver endothelial cell function in the postoperative period of liver transplantation.
Expression of determined Asn-bound glycans (N-glycans) in cell surface glycoproteins regulates different processes in tumour cell biology. Specific patterns of N-glycosylation are displayed by highly metastatic cells and it has been shown that inhibition of N-glycan processing restrains cell proliferation and induces cell death via apoptosis. However, the mechanisms by which different N-glycosylation states may regulate cell viability and growth are not understood. Since malignant cells express high levels of intracellular glutathione (GSH) and a reduction of intracellular GSH induces cell death via apoptosis, we investigated whether GSH was involved in the induction of apoptosis by removal of cell surface N-glycans. We found that removal of N-glycans from cell surface proteins by treating the rhabdomyosarcoma cell line S4MH with tunicamycin or N-glycosidase resulted in a reduction in intracellular GSH content and cell death via apoptosis. Moreover, GSH depletion caused by the specific inhibitor of GSH synthesis BSO induced apoptosis in S4MH cells. This data indicates that adequate N-glycosylation of cell surface glycoproteins is required for maintenance of intracellular GSH levels that are necessary for cell survival and proliferation.
A low molecular weight protease inhibitor peptide found in ovaries of the desert locust Schistocerca gregaria (SGPI-2), was purified from plasma of the same locust and sequenced. It was named SGCI. It was found active towards chymotrypsin and human leukocyte elastase. SGCI was synthesized using a solid-phase procedure and the sequence of its reactive site for chymotrypsin was determined. Compared with an inhibitor purified earlier from another locust species, the total sequence of SGCI showed 88% identity. In particular, the sequence of the reactive site of these inhibitors was identical. Our search for a closely related peptide in an insect species far removed from locusts, the lepidopteran Spodoptera littoralis, was unfruitful but a different chymotrypsin inhibitor, belonging to the Kazal family, was found whose mass is greater than that of SGCI (20 vs 3.6 kDa). Its N-terminal sequence shares 80% identity with that of a chymotrypsin inhibitor purified earlier from the haemolymph of another lepidopteran. Conservation of the amino acid sequence in the reactive site seems to be an exception among protease inhibitors.
In the title compound, [Ni(C(19)H(20)N(2)O(4))(H(2)O)(2)], the Ni atom has a distorted octahedral coordination geometry in which the tetradentate Schiff base ligand acts as a cis-N(2)O(2) donor defining an equatorial plane, and water molecules occupy the axial positions. The two parts of the molecule are related by a mirror plane that passes through the Ni atom and is perpendicular to the equatorial plane. The angular distortions from normal octahedral geometry are in the range 1-6 degrees, and the equatorial plane, defined by the donor atoms of the Schiff base, is almost square planar. The six-membered ring comprising the Ni, the imine N and the propylene C atoms adopts a half-chair conformation. The Ni-O [2.017 (2) A] and Ni-N [2.071 (2) A] distances are within the ranges expected for high-spin octahedral nickel complexes.
Glutathione (GSH) is the major non-protein thiol in cells that plays a critical role against damage from electrophilic agents such as alkylating drugs. Selective therapeutic GSH elevation in normal but not in tumour cells has been suggested as a means of protecting host tissues against more intense doses of chemotherapy. The present study investigated the response of B16 melanoma to treatment with the cysteine pro-drug L-2-oxothiazolidine-4-carboxylate (OTZ), alone and in combination with cyclophosphamide (CY). We found that OTZ decreased the GSH levels and proliferation rate of B16 melanoma cells in vitro, sensitizing them to the cytotoxic action of the activated metabolite of CY, acrolein (AC). In contrast to OTZ, the cysteine deliverer N-acetylcysteine (NAC) enhanced B16 melanoma cell proliferation by increasing GSH levels, and markedly decreased the sensitivity of these tumour cells to AC. In vivo studies showed the antitumoral activity of OTZ in B16 melanoma liver metastasis-induced mice, increasing their life span. We also observed that, whereas with CY treatment the GSH levels in peripheral blood mononuclear cells (PBMCs) were reduced and a dose-dependent leukopenia was produced, OTZ significantly increased PBMC GSH content, reducing toxicity and enhancing the survival of mice bearing established melanoma liver metastases treated with lethal dose CY. These results suggest a critical role for OTZ in protecting against alkylator agent-induced immunosuppression, which may allow the dose escalation of these cytostatic drugs to improve their therapeutic benefit in the treatment of malignant melanoma.
In an amazingly short time, electronic mail (e-mail) has become one of the most powerful and useful communication mediums in the health care workplace. However, while e-mail has added new dimensions to the communication system, which are advantageous, a concomitant effect is e-mail overload. By implementing e-mail management technique, strategies information overload can be controlled and effective productivity promoted.
BACKGROUND: The aim of our study was to evaluate the prevalence of Cys282Tyr mutation in patients with genetic haemochromatosis (GH) in Cantabria. PATIENTS AND METHODS: The HFE Cys282Tyr mutation was determined in a cohort of 60 patients with GH and 213 controls. RESULTS: The frequency of the Cys282Tyr mutation in control individuals was 4.4%. Sixty-seven percent of patients with GH were homozygous for the Cys282Tyr mutation. Twenty-seven percent of patients were normal at Cys282Tyr loci. CONCLUSIONS: The prevalence of the Cys282Tyr mutation in patients with GH in Cantabria, Spain, seems to be lower than in North America and in North Europe patients.
In this study we compare the effects of treatment with external sodium adenosine 5'-triphosphate (ATP) with the effects of L-buthionine-SR-sulfoximine (BSO) on B16 melanoma growth and on the modulation of the cytotoxic antimelanoma activity of cyclophosphamide (CY). We evaluated the in vitro effects of treatment with ATP or BSO on intracellular glutathione (GSH) levels, mitochondrial membrane potential (delta psi(m)) and the proliferation rate of the B16F10 melanoma cell line. Compared with untreated cells, delta psi(m) and GSH levels were already significantly decreased (25% and 57% reduction, respectively) after the first hour of incubation in culture cells exposed to 3 mM ATP. After 24 and 48 h a major reduction was observed in delta psi(m) (nearly 30%). GSH levels were also maximally depleted at 24 h (approximately 75%) and partially recovered (up to 37% of levels of control) after ATP was removed from the medium. At 24 and 48 h, the proliferation rate was decreased 1.4- and 1.7-fold, respectively, compared with control cells. Treatment with 50 microM BSO produced a time-dependent decrease in GSH levels (0.5, 21, 48 and 97.3% reduction at 1, 4, 8 and 24 h, respectively), but up to 54% of the levels of control cells was recovered after BSO was removed from the medium. In contrast to ATP, neither delta psi(m) nor proliferation rate was significantly modified in the first 24 h with BSO treatment. At 48 h, delta psi(m) was reduced by nearly 27%, and cell proliferation decreased 1.2-fold compared with controls. When the in vitro cytotoxic effect of low dose acrolein (an active metabolite of CY) in combination with BSO or ATP was analysed, a synergistic effect was found between BSO and acrolein, with a dose modification factor (DMF) of 1.98, but the antiproliferative effects of acrolein plus ATP were only approximately additive (DMF = 1.05). In addition, in in vivo studies differential effects were found between ATP and BSO. Specifically, whereas BSO alone significantly increased the survival time of mice bearing B16 melanoma liver metastases, and enhanced the cytotoxic effect of CY on this tumour model, no therapeutic benefits could be observed with ATP treatment, either alone or in combination with diethyl maleate (a GSH-depleting agent) and CY. In conclusion, our findings show that in our experimental system, both extracellular ATP and BSO have growth-inhibitory properties against B16 melanoma in vitro. In vivo, however, only BSO produces a chemosensitizing effect, whereas ATP has not proved useful as a biological modifier of chemotherapy.