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D Mack

Publications and source records attributed to D Mack.

At least 109 records · Page 6Linked to original sources
PubMed1992

[Lower toxicity with the topical low-dose BCG therapy of superficial bladder carcinoma?].

Twelve patients with superficial bladder cancer and carcinoma in situ of the bladder were treated with intravesically instilled BCG solution. As suggested by Pagano's group, we used BCG in a lower dose than usual hitherto (75 mg, strain Pasteur Paris). Complete tumor remission was obtained in all patients except the two whose treatment had to be discontinued at an early stage because of severe side effects. None of our patients was free of symptoms; pain or micturition, pollakiuria, gross hematuria, fever, swollen lymph nodes, and epididymitis occurred. We think, therefore, that low-dose therapy with BCG is as effective as full-dose therapy but the side effects are no less severe.

Administration, Intravesical↗
PubMed1991

Recognition by peptide mapping of three different structural groups of outer membrane protein YOP-1 of Yersinia enterocolitica and Yersinia pseudotuberculosis.

The structural relation of YOP-1 of "european" and "american" Yersinia enterocolitica serotypes O:3, O:9, O:5,27, and O:8 and O:20, respectively, and Y. pseudotuberculosis serotypes I, II, and III was compared by sodium dodecyl sulfate polyacrylamide gel electrophoresis and peptide mapping using Staphylococcus aureus protease V8. Apparent molecular weights of YOP-1 ranged from 206,000 (O:3) to approx. 180,000 (O:8). According to their respective peptide maps YOP-1 of the "european" and "american" Y. enterocolitica serotypes and Y. pseudotuberculosis serotypes could be assigned to three different groups. Evaluation of several isolates of Y. enterocolitica serotypes O:3, O:9, and O:8 by peptide mapping indicated that YOP-1 is conserved within a serotype. However, one serotype O:8 isolate differed from the consensus peptide pattern of the other serotype O:8 and O:20 isolates. The similarity of the peptide patterns of Yersinia serotypes which predominate in certain geographical locations, i.e., "european" and "american" Y. enterocolitica serotypes, suggest common evolution of YOP-1 of these serotypes independent of the evolution of the other serotypes.

Adhesins, Bacterial↗
PubMed1989

Immune responses associated with early survival after peroral infection with Toxoplasma gondii.

After peroral infection with cysts of Toxoplasma gondii, C57BL/6 mice died and A/J mice survived. To better understand the reasons for this difference in survival, host defenses during acute infection were studied: initial portal of entry of T. gondii contributed to susceptibility as more C57BL/6 mice survived after i.p. than peroral infection (p less than 0.001). Susceptible (C57BL/6) mice had more necrosis and inflammation in their brains, livers, and mesenteric lymph nodes than resistant (A/J) mice. Susceptible mice had less IgM antibody to T. gondii (p less than 0.0005) than resistant mice 7 days after infection, but amounts of IgG antibody to T. gondii were similar. Infection reduced percentages of spleen cells with the Lyt-2+ phenotype in susceptible (p less than 0.02) but not resistant mice; infection decreased percentages of spleen cells with the L3T4+ phenotype similarly in both strains of mice. Spleen cells from infected susceptible mice had greater depression in their blastogenic response to Con A (p less than 0.05) and produced significantly more IFN-gamma in culture with (p = 0.009) or without (p less than 0.05) Toxoplasma Ag than spleen cells from infected resistant mice. Infection increased serum levels of IFN-gamma substantially in susceptible but not resistant mice. Lymphocyte IL-2 production was similar in both groups of mice. Peritoneal macrophages from both strains of mice became activated to inhibit or kill T. gondii by 7 days after infection, but Kupffer cells became activated only in susceptible mice. These results indicate that increased resistance to peroral Toxoplasma infection is likely to be mediated by a number of immune responses acting together. They suggest that increased susceptibility may result from inadequately regulated inflammatory responses that increase tissue destruction.

Animals↗
PubMed1989

Muscle coenzyme Q deficiency in familial mitochondrial encephalomyopathy.

The electron transport system of muscle mitochondria was examined in a familial syndrome of lactacidemia, mitochondrial myopathy, and encephalopathy. The propositus, a 14-year-old female, and her 12-year-old sister had suffered from progressive muscle weakness, abnormal fatigability, and central nervous system dysfunction since early childhood. In the propositus, the state 3 respiratory rate of muscle mitochondria with NADH-linked substrates and with succinate was markedly reduced. The levels of cytochromes a + a3, b, and c + c1 were normal. The activities of complexes I, II, III, and IV of the electron transport chain were normal or increased. By contrast, the activities of complex I-III and of complex II-III, both of which need coenzyme Q10 (CoQ10), were abnormally low. On direct measurement, the mitochondrial CoQ10 content was 3.7% of the mean value observed in 10 controls. Serum and cultured fibroblasts of the propositus had normal CoQ10 contents. In the younger sister, the respiratory activities and CoQ10 level of muscle mitochondria were similar to those observed in the propositus. The findings establish CoQ10 deficiency as a cause of a familial mitochondrial cytopathy and suggest that the disease results from a tissue-specific defect of CoQ10 biosynthesis.

Adolescent↗
PubMed1989

Accessibility to proteases of the cytoplasmic G protein domain of vesicular stomatitis virus is increased during intracellular transport.

G1 and G2 are two forms of the membrane-integrated G protein of vesicular stomatitis virus that migrate differently in gel electrophoresis because G1 is modified by high-mannose and G2 by complex-type oligosaccharide side chains. The cytoplasmic domain in G1 is less exposed to cleavage by several proteases than in G2 molecules. Acylation by palmitic acid as well as inhibition of carbohydrate processing by swainsonine and deoxynojirimycin resulted in the same pattern of proteolytic sensitivity of both glycoproteins as in untreated cells. In contrast, accessibility of the cytoplasmic domain to proteases did not change when the intracellular transport of the G protein was blocked in carbonyl cyanide m-chlorophenylhydrazone- or monensin-treated BHK-21 cells, respectively. The results suggest that the increase in accessibility of the cytoplasmic tail of the G protein occurs after the monensin block in the trans-Golgi and might reflect a conformational change of functional significance--i.e., making the cytoplasmic domain of the viral spike protein competent for its interaction with the viral core, inducing thereby the formation of the budding virus particle.

Animals↗
PubMed1989

Enzymatic amplification of hepatitis B virus DNA in serum compared with infectivity testing in chimpanzees.

The in vivo infectivity titration of hepatitis B virus (HBV) has been biologically standardized in terms of chimpanzee infectious dose (CID50). The polymerase chain reaction (PCR) was used for in vitro enzymatic amplification of HBV DNA and comparison with CID50. Serial dilutions of human serum specimens containing HBV adw (CID50 10(-7] and ayw (CID50 10(-7.5] were tested to determine the reproducibility and sensitivity of PCR for the detection of HBV DNA. The detection limit of HBV DNA in serum using PCR was 10(-8) for either amplification of HBV DNA extracted from serum or direct amplification of HBV DNA in proteolyzed serum. The amplification efficiency of PCR in proteolysates was not significantly reduced by using a 0.25% concentration (vol/vol) of nonionic detergents and 2.5% concentration (vol/vol) of digested human serum. Thus, PCR is a specific and rapid method for in vitro detection of HBV DNA that is more sensitive than the in vivo infectivity titration of HBV by chimpanzee inoculation. Therefore, if HBV-related DNA cannot be detected by PCR in specimens or biologic products, they probably do not contain infectious HBV.

Animals↗
PubMed1989

Iron deficiency anemia in an athlete associated with Campylobacter pylori-negative chronic gastritis.

A 14-year-old athletic boy with a 1-year history of decreased exercise tolerance presented with unexplained iron deficiency anemia. Panendoscopy, colonoscopy, and barium contrast studies of the gastrointestinal tract were normal. However, persistent uptake of radionuclide using a 99mtechnetium-sucralfate scan suggested inflammation localized to the stomach. Mucosal biopsies demonstrated acute and chronic gastritis that was not associated with the presence of Campylobacter pylori.

Adolescent↗
PubMed1989

Acrodermatitis enteropathica with normal serum zinc levels: diagnostic value of small bowel biopsy and essential fatty acid determination.

We report a patient with acrodermatitis enteropathica and a normal serum zinc level in whom the diagnosis was confirmed by plasma phospholipid fatty acid and a small bowel biopsy response to oral zinc therapy. Acrodermatitis enteropathica is a rare autosomal recessive condition of zinc deficiency characterised by chronic diarrhoea associated with failure to thrive, periorificial dermatitis and alopecia, susceptibility to infections and behavioural changes. Diagnosis is usually established by reduced serum zinc levels (classical acrodermatitis enteropathica). Paneth cell abnormalities on electron microscope of a small bowel biopsy can be supportive. A few cases with the typical picture of acrodermatitis enteropathica without hypozincaemia (variant acrodermatitis enteropathica) have been described. The diagnosis of variant acrodermatitis enteropathica to date has been based on an entirely empiric, but nonetheless convincing clinical response to oral zinc therapy. Laboratory aids to diagnosis have been lacking.

Acrodermatitis↗
PubMed1989

Hyperemesis gravidarum and thyrotoxicosis--a diagnostic and therapeutic problem.

We report a case of hyperemesis gravidarum complicated by thyrotoxicosis which was managed conservatively during pregnancy. Problems of diagnosing mild thyrotoxicosis in pregnancy are discussed. Although no specific antithyroid therapy was given, the patient had an uneventful pregnancy after the first trimester. Neither she nor her baby exhibited any subsequent features of thyroid dysfunction. This suggests that treatment of thyrotoxicosis in early pregnancy is not always required because of the spontaneous improvement which is likely to occur as pregnancy progresses.

Female↗
PubMed1989

Rapid diagnosis of leukaemia: a three-stage immunophenotyping technique.

We have developed a three-stage avidin-biotin alkaline phosphatase system (ABAP) for immunophenotyping acute and chronic leukaemias. Air-dried blood and bone marrow films or cytospins were fixed in acetone, methanol-acetone, or methanol-acetone-formalin. A primary monoclonal antibody layer was employed with a corresponding biotinylated anti-species second layer. The third stage was avidin-conjugated alkaline phosphatase and visualisation was achieved with Fast Red TR as diazo salt. This was compared using a limited range of primary antibodies with the alkaline phosphatase anti-alkaline phosphatase (APAAP) method, routinely performed as a five-stage technique. The ABAP technique provided a 2.5 h, reliable, three-stage immunophenotyping procedure without the need for amplification steps. A wider range of first layer monoclonals of any species could be utilised by using the appropriate secondary antibody. Preservation of cell morphology was very good. Smaller amounts of expensive monoclonal antibodies could be used compared to the quantity required with other slide techniques. This approach to immunophenotyping can consequently be employed by any general haematology laboratory to provide a sensitive and inexpensive service. The technique has been in routine diagnostic use for the last 2 years, and consistently good results have so far been achieved in a national external immunophenotyping quality assurance scheme.

Acute Disease↗
PubMed1988

Fatty acid acylation at the single cysteine residue in the cytoplasmic domain of the glycoprotein of vesicular-stomatitis virus.

The cysteine residue in the cytoplasmic domain at position 489 of the sequence of the glycoprotein (G protein) isolated from vesicular-stomatitis virions is completely blocked for carboxymethylation. After release of covalently bound fatty acids by hydroxylamine at pH 6.8, this cysteine residue could be specifically labelled by iodo[14C]acetic acid. Reaction products were analysed after specific cleavage of labelled G protein at asparagine-glycine bonds by hydroxylamine at pH 9.3, which generated a C-terminal peptide of Mr 15,300 containing only the single cysteine residue. Bromelain digestion of [3H]palmitic acid-labelled membrane fractions of vesicular-stomatitis-virus-infected baby-hamster kidney cells removed almost completely the 3H radioactivity from the cytoplasmic domain of the G protein, whereas the ectodomain was completely protected by the microsomal membrane. This result indicates that the acylation site of the G protein is exposed on the cytoplasmic side of intracellular membranes. Taken together, both biochemical techniques strongly suggest that the single cysteine-489 residue, which is located six amino acid residues distal to the putative transmembrane domain, is the acylation site. The thioester bond between palmitic acid and the G protein is quite resistant to hydroxylamine treatment (0.32 M at pH 6.8 for 1 h at 37 degrees C) compared with the reactivity of the thioester linkage in palmitoyl-CoA, which is cleaved at relatively low concentrations of hydroxylamine (0.05 M).

Acylation↗
PubMed1988

Transmission of hepatitis B from hepatitis-B-seronegative subjects.

The polymerase chain reaction (PCR) was used to identify and characterise serum HBV DNA sequences in 3 patients negative for all HBV serological markers. HBsAg determinants were detected in 1 individual by monoclonal anti-HBsAg immunoradiometric assay. By use of sets of primers on the S and pre-S parts of the HBV genome the presence of HBV DNA was demonstrated in the serum of all 3 patients. Inoculation of human sera to 2 chimpanzees induced acute hepatitis in both animals; 1 became positive for HBsAg and anti-HBcAg and the other only for anti-HBsAg. Cloning of DNA sequences from viral isolates from 1 chimpanzee and 1 patient was accomplished after amplification of the 3' region of the S gene. Comparison of the partial nucleotide sequence with that of known HBV subtypes showed 0 and 1 point mutation, respectively, in the highly conserved 3' end of the S gene. Therefore the results show that PCR with HBV primers may unambigously identify HBV infectious particles among non-A, non-B viruses and is a potentially useful diagnostic test for detection of HBV DNA sequences in serum.

Animals↗
PubMed1988

Delayed formation of defective interfering particles in vesicular stomatitis virus-infected cells: kinetic studies of viral protein and RNA synthesis during autointerference.

The time course of defective interfering (DI) particle and B particle release from vesicular stomatitis virus-infected BHK-21 cells was studied at different multiplicities of defective and infective particles. Particle release was progressively delayed in cells infected with an increasing DI-to-B particle ratio. The delayed particle release during interference was found to be connected with a reduced but prolonged synthesis of viral proteins, a slower accumulation of viral proteins, and a delayed shutoff of cellular protein synthesis. The relative synthesis of M and G proteins was reduced during interference, whereas the relative synthesis of N and NS proteins was increased. On the level of genomic RNA replication, we found that DI RNA was replicated more slowly during interference than the standard genomic RNA was during acute infection. The ratio of DI particles to B particles which were released increased throughout the infectious cycle. At a given time in the infectious cycle, this ratio was independent of the multiplicity of infecting DI and B particles. On the basis of the kinetic studies, we argue that cells infected with higher amounts of DI particles compared with B particles synthesize a higher DI-to-B particle ratio and release these progeny particles later than cells infected with a low DI-to-B particle ratio.

Animals↗
PubMed1988

Urinary diversion in gynecologic malignancies.

A variety of methods for urinary diversion are employed in patients with gynecologic malignancies depending on whether there is an obstruction or fistula formation due to either tumor growth or radiotherapeutic injury. Percutaneous nephrostomy (PCN) has a low complication rate and is a good method for palliative urinary diversion or may precede some form of permanent diversion to restore the kidney function first. Indication for palliative diversion in tumor obstruction depends on many individual factors. A relative contraindication is tumor progression during therapy. 6-month survival was about 70% in patients with previously untreated tumors or recurrences. This rate is far better than reported in earlier studies, so that a palliative diversion has to be considered for these patients. Also a high rate of recanalization after therapy could be observed in the untreated group, allowing the PCN to be removed. However, this has not been shown to be a prognostic factor. In the individual patient some other aspects, such as quality of life and social status, have to be taken into account before a final decision can be made. Ureteral obstruction after radiotherapy is a rare finding and often mistaken for a more likely recurrence. Different methods to restore the urinary tract, such as reimplantation of the ureter, should be used as a first choice. When the stenosis is due to radiocystitis, enterocytoplasty will often be indicated. Diversion has then to be omitted. The poor quality of life because of permanent incontinence due to fistula formation makes diversion mandatory even if life expectancy is very short. Surgical closure of a large radiogenic fistula is rarely successful. In this situation, ileal conduit has proven its efficacy for long-term urinary diversion.

Female↗