Der chirurgische Part im Rahmen multimodaler Therapiekonzepte in der Onkologie-Schilddrüse

29. Tagung der ?sterreichischen Gesellschaft für Chirurgie und Ihrer Assoziierten Fachgesellschaften Innsbruck, 2. bis 4. Juni 1988 Herausgeber: E. Bodner und G. Szinicz Abstracts

Der chirurgische Part im Rahmen multimodaler Therapiekonzepte in der Onkologie-Schilddrüse     

A simple bactericidal antibody test for sero-diagnosis of typhoid fever

Serum samples were collected from 24 confirmed cases of typhoid fever, 15 clinically suspected cases and 23 normal healthy controls. The convalescent sera were obtained in 13 of the 24 confirmed typhoid cases. In all, 13 paired sera, 11 acute phase only, 15 clinically suspected and 23 normal serum samples were tested for eliciting bactericidal antibodies to Salmonella typhi. In addition, the Widal test was also performed for comparison. All the 24 acute phase sera as well as 13 convalescent sera were found to be positive by bactericidal antibody test (titre 1:80 or above). Of 15 clinically suspected cases, 5 were positive whereas one of the 23 normal controls sera gave a false positive reaction. In contrast, the Widal test could detect only one of the 24 cases in the acute stage, but all 13 cases showed antibodies at a diagnostic titre level during the convalescent stage. None of the 15 clinically suspected cases or 23 normal controls were positive by the Widal test. The feasibility of using a bactericidal antibody test in sero-diagnosis of typhoid fever is discussed.     

Regulation of NK cell function in vivo by the dose of tumour transplanted in the peritoneum

Antigen dose is known to regulate T cell activation and anergy. Similarly, dose of antigen also regulates NK cell lytic potential and phenotype development. Resident peritoneal cells of rat contain a small population of NK and NKT cells. Inoculation of AK-5 tumour cells intraperitoneally modulate the cytotoxic function of NK and NKT cells present in the peritoneal exudate cells (PEC) in a dose dependent manner. Low dose of tumour causes activation of NK and NKT cell cytotoxic function and enhanced NK and NKT cell population in PEC, whereas, high doses of tumour cause inactivation of NK and NKT cell cytotoxic function and depletion of the two sub-populations in the peritoneum. Different doses of tumour inoculation in the peritoneal cavity did not suppress the cytotoxic function of NK cells from spleen suggesting that a direct interaction between NK cells and tumour cells is required for the suppression of NK cell cytotoxic function. Tumour inoculation induced secretion of IL-2, IL-12, IFN-gamma and TNF-alpha by tumour infiltrating mononuclear cells (TIM) in ascitic fluid as well as in serum. The levels of IL-2, IL-12, IFN-gamma and TNF-alpha secretion were higher in animals, which rejected tumours as compared with the animals that failed to reject the tumours. Injection of anti IL-12 and anti IFN-gamma antibody reduced the survival rate of tumour injected animals, however, anti IL-2 antibody had no effect on the survival of animals. Following incubation with AK-5 tumour cells, activated NK cells upregulated perform expression, whereas, there was upregulation of CD95 expression in inactivated NK cells.     

Serodiagnostic efficiency of phospholipid associated protein of Mycobacterium tuberculosis H37Rv

The phospholipid-associated protein (55–67 kDa) fraction of Mycobacterium tuberculosis H₃₇Rv was purified as the DE-V protein fraction. This DE-V fraction was used for diagnosis of tuberculosis by enzyme-linked immunosorbent assay (ELISA), detecting IgG antibody in sera collected from different categories of tuberculosis patients, i.e. with acid fast bacilli (AFB) culture-positive pulmonary tuberculosis, with AFB culture-negative, but radiologically suspected, pulmonary tuberculosis, extrapulmonary tuberculosis, and control groups of patients suffering from diseases other than tuberculosis (asthma and/or rhinitis, lepromatous leprosy) as well as from healthy volunteers. Encouraging operational ELISA validity could be achieved with 93% sensitivity, 100% specificity, 97% efficiency, 100% positive predictivity and 95% negative predictability even among the extrapulmonary and suspected pulmonary tuberculosis patients. The above assay was insensitive but with 100% specificity among control group of patients suffering from diseases other than tuberculosis. The DE-V protein fraction was associated with phosphatidyl inositol and phosphatidyl inositol mannosides. The dissociation of phospholipid-protein complex decreased ELISA specificity. ELISA reactivity of the DE-V fraction appeared to be thermostable; thus, it may have serodiagnostic utility in developing countries.     

Inverse trend between estimated worldwide frequency of major cancers and inferred infectious burdens of populations: possible role of adaptive immune system

Regions of the world subjected to heavy infectious burdens seem to show lower incidence of cancer. The index of infectious burden in this study has been chosen to be poverty, i.e., low GDP, high infantile mortality, poor hygienic conditions, inaccessibility to modern medical infra-structures, etc. When estimates of observed cancer incidence is plotted against the GDP of 24 regions of the world, a trend line is obtained: low GDP (a proxy for high infectious burden) tends to be associated with low incidence of cancer whereas high GDP values herald higher cancer occurrences. Similarly, countries with high infantile mortality rates tend to have a lower incidence of cancer and vice versa. The data are explained in terms of the so-called "hygiene hypothesis": frequent infectious onslaughts, especially in childhood, challenge the immune system and build a strong adaptive immune system and immunological memory which prepare the body to tackle further battles down the line, such as cancer. Within this framework, the role of other factors such as diet, selenium, hardness of water, etc. in the aetiology of cancer is also briefly examined. For rigorous verification of this observation, age-adjusted cancer incidence rates for various countries must be used even though such data are not available for all the countries examined here [Bulletin of World Health Organization 62(2) (1984) 163]; where data are available [Age-adjusted death rates for cancer for selected sites (A classification) in 51 countries in 1974, Segi Institute of Cancer Epidemiology, Nagoya, Japan (Feb. 1979); Global Geocancerology, Churchill Livingstone, New York, 1986], the same trend is also observed for the age-adjusted cancer death rates, which may be used as an index of age-adjusted cancer incidence, subject to qualifications discussed in the text.     

Enhanced molecular volume of conservatively pegylated Hb: (SP-PEG5K)6-HbA is non-hypertensive

Recent studies have suggested that the "pressor effect" of acellular Hb is a consequence of perturbation of the macro-and microcirculatory system in multiple ways, and that PEGylation is an effective approach for controlling the same. In an attempt to confirm this concept, a new and simple thiolation mediated, maleimide chemistry-based conservative PEGylation protocol has been developed to conjugate multiple copies of PEG-chains to Hb. This approach combines the high reactivity of maleimides towards thiols with the propensity of iminothiolane to derivatize the epsilon-amino groups of proteins into reactive thiol groups, with conservation of their positive charge. One of the PEGylated products, namely (SP-PEG5K)6-HbA, that carries on an average six copies of PEG5000 chains per Hb, is non-hypertensive in hamster top load and in rat 50% exchange transfusion models. This hexa-PEGylated-Hb has (i) a hydrodynamic volume corresponding to that of an oligomerized Hb of 256kDa, (ii) a molecular radius of approximately 6.8 nm, (iii) high oxygen affinity, (iv) lowered Bohr effect, and (v) increased viscosity and colloidal osmotic pressure. These properties of (SP-PEG5K)6-HbA are consistent with the emerging new paradigms for the design of Hb based oxygen carriers and confirm the concept that the "pressor effect" of Hb is a multifactorial event. The thiolation mediated maleimide chemistry-based PEGylation protocol described here for the generation of (SP-PEG5K)6-Hb is simple, highly efficient, and is carried out under oxy conditions. The results demonstrate that a non-hypertensive PEG-Hb can be generated by conjugation of a lower number of PEG chains than previously reported.     

Affinity fractionation of lymphocytes using a monolithic cryogel

A new type of continuous, supermacroporous, monolithic, cryogel affinity adsorbent was developed, allowing specific fractionation and separation of human peripheral blood lymphocytes in a chromatographic format. The affinity adsorbent was used to design a novel cell separation strategy, which was based on the interaction of protein A from Staphylococcus aureus with cells bearing IgG antibodies on the surface. After treating lymphocytes with goat anti-human IgG(H+L), the IgG-positive B-lymphocytes were efficiently separated from T-lymphocytes. Protein A covalently coupled to epoxy activated dimethylacrylamide (DMAA) cryogel matrix specifically bound IgG-bearing B-lymphocytes through the Fc region, while non-bound T-lymphocytes passed through the column. More than 90% of the B-lymphocytes were retained in the column while the cells in the breakthrough fraction were enriched in T-lymphocytes (81%). The viability of the T-lymphocytes isolated was greater than 90%. The bound lymphocytes released by human or dog IgG recovered 60-70% of the B-cells without significantly impairing the cell viability. The technique can be applied in general to cell separation systems where IgG antibodies against specific cell surface markers are available.     

An effective regimen for early medical abortion: a report of 2000 consecutive cases

A combination of the anti-progesterone mifepristone and gemeprostprovides an effective non-surgical method for the inductionof abortion at gestations up to 63 days, achieving completeabortion rates of over 95%. We report our experience with analternate regimen, comprising a reduced dose of mifepristonein combination with vaginal misoprostol. A consecutive seriesof 2000 women requesting early medical abortion at gestationsup to 63 days was studied retrospectively. Each woman receivedmifepristone 200 mg orally, followed 36–48 h later bymisoprostol 800 µg vaginally. Of the 2000 women, 39 (2.0%)aborted completely following administration of mifepristonealone and a further 1912 experienced complete abortion followingadministration of misoprostol (a complete abortion rate of 97.5%).Surgical intervention was required in 49 women (2.5%): for incompleteabortion in 27 (1.4%), for missed abortion in seven (0.4%),for continuing pregnancy in 11 (0.6%) and to exclude ectopicpregnancy in four (0.2%). The surgical intervention rate wassignificantly higher among women at gestations 49 days thanamong those at 49 days (3.3 versus 1.5%, P = 0.0193). The regimenappears as effective, in terms of high complete abortion rateand low continuing pregnancy rate, as any published alternative.This regimen has the benefit of being less costly as the doseof mifepristone is 67% lower and misoprostol is substantiallyless expensive than gemeprost. Additionally, misoprostol doesnot require special transport or storage requirements. As such,the combination of mifepristone and gemeprost.     

Comparative mutagenic and genotoxic effects of three antimalarial drugs, chloroquine, primaquine and amodiaquine

Comparative mutagenic and genotoxic effects of three antimalarialdrugs, chloroquine, primaquine and amodiaquine, were assessedin the Ames mutagenicity assay (in strains TA97a, TA100, TA102and TA104) and in vivo sister chromatid exchange (SCE) and chromosomeaberration (CA) assays in bone marrow cells of mice. These arethe most commonly used antimalarial drugs available at presentthroughout the world. The results of the bacterial mutagenicityassays showed a very weak mutagenic effect of all three drugsin Salmonella strains TA97a and TA100 both with and withoutS9 mix and in TA104 only with S9 mix. The results of the invivo SCE and CA assays indicate that these three drugs are genotoxicin bone marrow cells of mice. ³To whom correspodence should be addressed. Tel: +91 33 473 3491; Fax: +91 33 473 5197; Email: iichbio{at}giascl01.vsnl.net.in