Synergistic interaction of ABCB1 and ABCG2 polymorphisms predicts the prevalence of toxic encephalopathy during anticancer chemotherapy.

Polymorphisms of the ABCB1 (MDR1) and ABCG2 (BCRP) genes were reported to alter the expression and function of these drug transporters. Both proteins are present at the main pharmacokinetic barriers including the blood-brain barrier. Data from 291 children with acute lymphoblastic leukaemia were analysed in this retrospective study. ABCB1 3435T>C, 2677G>T/A, 1236C>T and ABCG2 421C>A, 34G>A genotypes were determined. Encephalopathy episodes were more frequent among those with ABCB1 3435TT genotype than in the 3435CC/CT group (odds ratio (OR) 3.5; P=0.03). Patients with the ABCG2 421A allele tended to have more complications than wild type homozygotes (OR=2.0; P=0.25). The rate of the adverse effect was similar in those harbouring no or only one of the predisposing genotypes, that is, either ABCB1 3435TT or ABCG2 421AA/AC. However, significantly more children suffered encephalopathy in the group with both predisposing genotypes (OR=12.3; P=0.005). In conclusion, these variations exert synergistic effect in predisposing patients to toxic neurological complications of chemotherapy.

Patterning of B16 melanoma metastasis and colonization generally relates to tumor cell growth-stimulating or growth-inhibiting effects of organs and tissues.

The mouse B16 melanoma metastasizes first to the lungs and secondarily to systemic sites, involving mainly the adrenals, ovaries and pancreas. Systemic colonization effected by intracardiac injection of tumor cells establishes similar patterning, but in addition frequently colonizes the bones. To assess possible systemic site influences on metastasis and colony formation, the capacity of B16 melanoma cells to proliferate in these sites in vivo and in ex vivo explants following intracardiac injection was examined. Effects of cells isolated from these sites, and of organ- or tissue-conditioned medium, on growth of B16 cells in monolayer culture were also studied. Injected fluorochrome-labeled tumor cells initially distributed without site preference, but within 48 h had begun proliferating in the adrenals, ovaries and lungs, while remaining static in the pancreas and bones, and disappearing from the spleen, liver, kidneys, brain, and skeletal muscles. Mitogenic activity releasable in soluble form was associated with all favorable organs and tissues and was the predominant influence of those tissues on cultured tumor cells. In contrast, the overall effects of liver, spleen, kidney, and brain tissues were to inhibit tumor cell growth. Soluble growth-promoting activity enhanced clonogenic growth of isolated tumor cells stimulated by mouse serum, suggesting that metastasis or colony formation might be stimulated in favorable sites by those factors together with blood-borne growth factors. The observed effects of organ- and tissue-derived cells and soluble factors on tumor cells generally reflected the in vivo consequences of tumor cell entrapment in the corresponding sites. However, the failure of metastases to develop in the bones, which are favorable sites for colonization by the same cells, remains puzzling.

Separation of lipids by new thin-layer chromatography and overpressured thin-layer chromatography methods.

New methods were developed for the separation of major lipid classes varying in polarity from cholesterol esters to lysophosphatidylcholine. The methods were used for the analysis of extracts obtained from human sera. The lipids were separated by overpressured thin-layer chromatography, classical thin-layer chromatography, and one-dimensional thin layer chromatography, using six different solvent systems for development. These techniques are also suitable to separate unsaturated and saturated cholesterol esters according to the number of carbon atoms and double bond numbers of their constituent fatty acids.

Successful treatment of a generalized human papillomavirus infection with granulocyte-macrophage colony-stimulating factor and interferon gamma immunotherapy in a patient with a primary immunodeficiency and cyclic neutropenia.

BACKGROUND: We describe a patient with generalized verrucosis secondary to human papillomavirus (HPV) type 2 infection and a primary immunodeficiency and cyclic neutropenia. Treatment, which was well tolerated, included granulocyte-macrophage colony-stimulating factor and interferon gamma (IFN-gamma). In vitro assays to assess responses of T lymphocytes to mitogens (ie, proliferation assay and IFN-gamma enzyme-linked immunosorbent assay) were performed. In situ hybridization and polymerase chain reaction were used to detect HPV DNA in skin biopsy specimens. OBSERVATIONS: The T lymphocytes of the patient showed a significant (P < .05, unpaired Student t test) defect in IFN-gamma production (the basis for initiating IFN-gamma therapy). The response to immunotherapy was confirmed by using molecular methods. Six months after the completion of immunotherapy, HPV DNA was undetectable in skin samples from clinically regressed warts (according to the results of in situ hybridization and polymerase chain reaction). CONCLUSIONS: Our patient had treatment-resistant generalized verrucosis for 13 years. Treatment with granulocyte-macrophage colony-stimulating factor and IFN-gamma may have reconstituted an immune response against HPV, resulting in the dramatic regression of her widespread warts.

[Qualitative and quantitative detection of hepatitis C virus RNA by PCR technique. Monitoring of viral copies after liver transplantation]. / Hepatitis C-vírus (HCV)-RNS kvalitatív és kvantitatív kimutatása PCR technikával. A HCV-RNS-kópiaszám monitorozása májtranszplantációt követóen.

The authors demonstrate the HCV nucleic acid amplification method is not wide-spread in Hungary yet. The HCV-RNA is usually detectable 2-4 weeks after infection independently the immunostate of the patients. The authors help to select the adequate measurement(s) in logical order when HCV infection is suspected. The benefit of the PCR method is emphasized. Monitoring of the HCV-RNA titer of the liver transplanted patients promotes to establish the fluctuation of HCV-RNA copies and the effectivity of therapy following transplantation. The detection of HCV-RNA by PCR method is a proof of an acute or chronic infection and rules out past infection. The quantitative PCR measurement is useful for determination of indication and control of efficacy of antiviral therapy.

Commonly used suture materials in skin surgery.

The ideal suture is strong, handles easily and forms secure knots. It causes minimal tissue inflammation and does not promote infection. It stretches, accommodates wound edema and recoils to its original length with wound contraction. Ideally, it is also inexpensive. Although no single suture material possesses all of these features, proper selection of sutures helps achieve better results in skin surgery. Among the absorbable sutures are catgut and treated catgut (both are used infrequently) and the synthetic sutures, which are designed for good tensile strength, easy handling and low tissue reactivity. Nonabsorbable sutures include silk (now infrequently used) and several synthetic materials designed for elasticity, easy handling, good knot security and minimal tissue irritation.

Commonly used suturing techniques in skin surgery.

Proper suturing technique is essential for obtaining good cosmetic results and avoiding infection, scarring and poor wound healing. Techniques that must be mastered include good eversion of skin edges, avoiding suture marks, maintaining uniform tensile strength along the skin edges and precise approximation of skin edges. Vertical mattress sutures have the advantage of good wound eversion and closure of dead space. Running continuous sutures can be quickly placed and divide tension equally along the skin edge. Interrupted sutures are more time-consuming but allow more precise wound edge approximation, while subcuticular sutures are useful for avoiding suture marks in conspicuous areas.