Exhaustion of Vascular Endowment in Hemodialysis: Proposal for a Permanent Inlet Access

The subcutaneous reservoir is a new vascular access for patients on regular hemodialysis (HD).

A double chamber in Titanium- Pirolytic Carbon with siliconic boreable superior caps is inserted in to a subcutaneous subclavian side, and always in subcutis connected to two siliconic catheters located in the right jugular resulting in the right atrium.

The puncture of each chamber is performed with a special hemodialysis-cannula telescopically assembled on a “dilatation tube”, in which a stylet is inserted.

In correct sequence, the cutaneous planes and the caps are bored, dilated, and finally the HD cannula after sliding over the previous structures is positioned in the inner chamber, closing the HD circuit.

In our study two patients were implanted, with a survival of 24 months, good compliance, no cardiovascular impairments and lack of catheteral pathology.

Natural NS5A inhibitor resistance associated substitutions in hepatitis C virus genotype 1 infected patients from Italy

OBJECTIVES

Genetic variability in NS5A is associated with different levels of resistance to the currently licensed NS5A inhibitors. The aim of this study was to detect NS5A inhibitor resistance associated substitutions (RASs) in hepatitis C virus (HCV) genotype 1 (GT1) patients who are naive to direct-acting HCV antivirals.

METHODS

Amplification, Sanger sequencing and phylogenetic analysis of the HCV NS5A region were performed on plasma obtained from 122 consecutive patients with HCV chronic infection attending four different clinics in Italy.

RESULTS

NS5A inhibitor RASs were detected in 14/61 (23.0%) HCV GT1b and 3/61 (4.9%) HCV GT1a infected patients (p 0.007). The pan-genotypic RAS Y93H was detected in 1 (1.6%) GT1a and 4 (6.6%) GT1b patients. GT1a sequences clustered into two different clades with RASs detected in 1/34 (2.9%) clade I and 2/27 (7.4%) clade II sequences.

CONCLUSIONS

Although the impact of naturally occurring NS5A RASs might be limited with upcoming pan-genotypic treatment regimens, this information is still useful to map naturally occurring HCV variants in different geographic areas in the context of current HCV therapy.

Phorbol 12-myristate 13-acetate (pma) induces neuroendocrine-like differentiation and reverses Doxorubicin-resistance of human colon-carcinoma cells in-vitro

Human colon carcinoma LoVo/DX cells, which have been selected from parental LoVo for resistance to doxorubicin, express a typical multidrug resistant (MDR-1) phenotype. We have investigated whether phorbol 12-myristate 13-acetate (PMA) which often induces phenotypical changes in human tumor cells could, at the same time, modulate differentiation and sensitivity of LoVo/DX cells to doxorubicin. After 48 h exposure to 100 nM PMA, morphological changes became evident on LoVo/DX cells which showed elongated cytoplasm and dendritic-like structures: moreover immunocytochemical findings were suggestive of neuroendocrine-like differentiation. Under the same experimental conditions, LoVo/DX became sensitive to doxorubicin and showed enhanced intracellular drug-accumulation and reduced membrane expression of the 170 kD glycoprotein GP-170, which is the cellular product of the mdr1 gene. We conclude that pharmacological induction of tumor cell differentiation by PMA is paralleled by abrogation of drug resistance in a colon carcinoma MDR-1 cell line.

Cerebral abscess caused by Capnocytophaga spp in an immunocompetent subject: case report

Capnocytophaga spp are Gram-negative bacteria commonly identified as oral saprophytes of humans, dogs and cats; they rarely cause invasive infections in immunocompetent subjects. This case report is about a rare case of cerebral abscess caused by Capnocytophaga spp in an immunocompetent subject who had no risk factors for Capnocytophaga invasive infections (oral alterations, traumatic or iatrogenic lesions of pharynx and/or oesophagus, recent dog bite). We also report Capnocytophaga spp naturally resistant to metronidazole, this being the cause of inefficacy of this drug usually included in empiric chemotherapy of cerebral abscess.

Muscular-skeletal cryptococcosis in a patient with idiopathic CD4+ lymphopenia

A healthy 27-year-old woman presented, four months after childbirth, ingravescent pain and claudication of the left lower limb. Magnetic Resonance Imaging of the lumbosacral and iliac regions showed widespread muscular-skeletal lesions. The patient underwent surgery; Cryptococcus neoformans was isolated from surgical samples. Liposomal amphotericin B, fluconazole and itraconazole were administered. Laboratory findings showed lymphocytopenia, with reduction of CD4+ lymphocytes (23 cells per cubic millimeter) in the absence of HIV infection and any other defined immunodeficiency. This is a rare case of muscular-skeletal cryptococcal infection isolated in a subject affected with idiopathic CD4+ lymphocytopenia.

Exhaustion of vascular endowment in hemodialysis: proposal for a permanent inlet access

The subcutaneous reservoir is a new vascular access for patients on regular hemodialysis (HD). A double chamber in Titanium- Pirolytic Carbon with siliconic boreable superior caps is inserted in to a subcutaneous subclavian side, and always in subcutis connected to two siliconic catheters located in the right jugular resulting in the right atrium. The puncture of each chamber is performed with a special hemodialysis-cannula telescopically assembled on a "dilatation tube", in which a stylet is inserted. In correct sequence, the cutaneous planes and the caps are bored, dilated, and finally the HD cannula after sliding over the previous structures is positioned in the inner chamber, closing the HD circuit. In our study two patients were implanted, with a survival of 24 months, good compliance, no cardiovascular impairments and lack of catheteral pathology.

Daily low-dose subcutaneous recombinant interleukin-2 by alternate weekly administration: antitumor activity and immunomodulatory effects

A phase II clinical trial of subcutaneous recombinant Interleukin 2 (rIL-2) given by 5 days pulses followed by a 9 days rest has been performed in patients affected by renal cell carcinoma, malignant melanoma and colorectal cancer. A total of 25 patients entered the study, completed at least six courses of treatment, and were evaluable for toxicity and response to treatment. This schedule of subcutaneous rIL-2 was well tolerated and no World Health Organization grade 3 side effects were observed. A 33.3% response rate was recorded in patients affected by renal cell carcinoma, although no major responses were achieved in patients with malignant melanoma and colorectal cancer. A durable increase of natural killer activity retained by poeripheral blood mononuclear cells was demonstrated in these patients and was paralleled by increased serum levels of interferon gamma and tumor necrosis factor a without changes of circulating interleukin-1d. It is concluded that this schedule of pulse administration of subcutaneous rIL-2 has antitumor activity in renal cell carcinoma and produces durable biomodulatory effects.

Transient exposure to cytarabine increases peptide growth factor receptor expression and tumorigenicity of melanoma cells

We have demonstrated that anticancer drugs at cytostatic concentrations enhance the expression and function of epidermal growth factor (EGF-R) and transferrin (TRF-R) receptors on human tumor cells. We hypothesized that these effects could represent a protective response of tumor cells to sublethal antiproliferative stimuli which could lead to enhanced growth potential. 72 hours exposure of human melanoma GLL-19 cells to 1,000 nM ara-C induced growth inhibition and increased the number of EGF-R, TRF-R and nerve growth factor receptor (NGF-R) on cell surface. Enhanced expression of beta 3 integrins CD49a, CD49c and CD49e, av integrin CD51, beta 3 integrin CD61, CD58/LFA3 and collagen IV and laminin was also detected in ara-C-treated GLL-19 cells. These changes at the tumor cell surface were paralleled by increased in vitro adhesion, invasive potential and clonogenic growth in soft agar and in vivo tumor formation. A more aggressive tumor cell phenotype is induced in human melanoma cells after transient exposure to cytostatic concentrations of ara-C.

alpha-Interferon potentiates the growth inhibitory effects of anti-transferrin receptor monoclonal antibodies

We have demonstrated that interferon-alpha 2 recombinant (IFN alpha) inhibits the growth and modulates the expression of the receptor for transferrin (TRF-R) in human epidermoid carcinoma KB cells. Receptor upregulation results in the reconstitution of intracellular iron levels in the IFN alpha-treated cells. Several anti-TRF-R murine monoclonal antibodies (MAbs) have been generated which induce tumor cell growth inhibition through blockade of receptor function. We have evaluated by MTT assay the effect of anti-TRF-R 42/6, E2.3, A27.15 and D65.30 MAbs given in combination with IFN alpha on the growth of human epidermoid carcinoma KB cells. We found that IFN alpha and A27.15 MAb induced a synergistic antiproliferative effect on these cells. These results suggest that IFN alpha may potentiate the antitumor efficacy of TRF-R-targeted therapy.

[Blood aluminum in a population of hemodialyzed patients. 1981-1991: a comparison of a decade]

The authors report their data on the behaviour of serum aluminium registered at a 10 year interval among a population of haemodialyzed patients. Improved knowledge of the toxic role of aluminium and of the sources of pollution in dialyzed patients seems to relegate the neurologic toxicity of aluminium to a historical aspect.

L-carnitine and platelet aggregation in uremic patients subjected to hemodialysis

It has been reported that treatment with L-carnitine at a daily dose of 3 g orally may cause a rise in platelet aggregation and serum triglyceride concentration in hemodialyzed patients. The present double-blind cross-over study has been performed to evaluate the influence of L-carnitine when compared with placebo on platelet aggregation and plasma concentrations of various factors involved in platelet activation. In addition, the concentration of triglycerides, cholesterol and HDL-cholesterol has been evaluated. 18 uremic patients on maintenance hemodialysis for at least 1 year were randomly allocated either to a control group receiving placebo or to a group treated with L-carnitine. Statistical analysis performed by means of ANOVA did not show any significant change in the serum concentration of cholesterol, HDL-cholesterol and triglycerides. Furthermore, platelet aggregation tests (performed with adenosine 5'-diphosphate, epinephrine, thrombin and collagen) and plasma beta-thromboglobulin concentration did not show any statistically significant difference. In addition, the plasma concentration of several coagulation markers, such as factor VIIIc, antithrombin III, alpha 2-antiplasmin, and fibrinopeptide A, did not show any significant variation. The results suggest that under our experimental conditions L-carnitine neither increases the risk of thromboembolism nor alters the serum lipid content in uremic patients on chronic hemodialysis.