Serological diagnosis of HIV infection: incidence, outcome and significance of partial reactions found in western blot analysis.

Between May 1986 and April 1987 routine screening for anti-HIV antibody was performed by enzyme immunoassay (EIA) on 3344 serum samples. The 1160 samples found positive or borderline were further analysed in Western blot (Wb). We analysed the frequency of different patterns of 'intermediate' Wb reactions (1-3 'specific' bands) and tried to determine their significance by searching for possible modifications of the pattern of reaction a few months later. Of 1160 Wb, 461 were clearly positive, 489 negative and 210 'intermediate'. The latter consisted of: 92 sera with anti-p24 (associated or not), 23 with anti-gp 120 and 160, 16 with anti-p55, 12 with anti-p41, 10 with anti-p65, eight with anti-p17 and four with anti-p31. A non-specific pattern was observed in the remaining 45. Of these sera, 46% were obtained from high risk subjects, 38% from persons without risk and in 16% no reliable information was available. In 30 subjects (24 with p24 and 6 with p41), a second sample was obtained about three months later. The reaction persisted in nine, was replaced by another in five, and disappeared in 15. One subject with anti-p41 in the first sample became clearly positive. In one of the 15 samples with disappearance of the reaction, the antigen p24 was present as the only sign of HIV infection. Later samples of this subject showed clear seroconversion. In many subjects with and without risk of exposure to HIV, the Wb gives an intermediate pattern of reactions (1-3 specific bands), that does not permit definitive conclusion on one single sample. Later controls are therefore necessary. Most of these reactions do not correspond to HIV infection.     

Relationship between slow-wave EEG bursts and heart rate changes in preterm infants

The objective of the study is to explore interactions between cortical and autonomic functions in the first weeks of postnatal life. We investigated the behaviour of one-channel electroencephalogram (EEG) patterns and heart rate (HR) dynamics in preterm infants. In a group of 15 healthy preterm infants with a mean conceptional age (CA) of 36 weeks and a mean postnatal age of 17.5 days simultaneous registration of amplitude integrated EEG (aEEG) and HR pattern was performed during interfeeding intervals. Periods with a discontinuous EEG activity and a low heart-rate variability (HRV) were selected for further processing and averaging. It was found that spontaneous activity transients (SATs) or slow wave EEG bursts during "Tracé alternant" (TA) can be accompanied by an HR acceleration of 1-2% (mean: 1.9, range: 0.6-3.5 beats/min) lasting approximately 5s (mean, range: 3.6-7.1s). The aim of the study is to give evidence of a coherent behaviour of EEG bursts and HR in the developing nervous system of preterm infants.     

Reduction of Diagnostic Window by New Fourth-Generation Human Immunodeficiency Virus Screening Assays

In order to reduce the diagnostic window between the time of human immunodeficiency virus (HIV) infection and laboratory diagnosis, new screening enzyme-linked immunosorbent assays (ELISAs) which permit the simultaneous detection of HIV antigen and antibody have been developed. Two fourth-generation assays, HIV DUO (Biomérieux) and HIV Combi (Boehringer Mannheim), for the combined detection of HIV antigen and antibody, were compared with a third-generation assay (HIV-1/HIV-2 3rd Generation Plus enzyme immunoassay [EIA]; Abbott) and a p24 antigen test (HIV-1 Ag monoclonal; Abbott). A total of 17 seroconversion panels, 15 cell culture supernatants infected with different HIV type 1 (HIV-1) subtypes, and 255 potentially cross-reactive serum samples were tested. Ten seroconversions were detected an average of 8.1 days earlier with HIV DUO and 7.5 days earlier with HIV Combi than with the third-generation ELISA. Overall, in the 17 seroconversion panels tested, HIV DUO detected HIV-1 infection an average of 4.8 days and HIV Combi detected infection an average of 4.4 days earlier than HIV-1/HIV-2 3rd Generation Plus EIA. HIV antigen was detected with HIV DUO and HIV Combi in all of the 15 cell culture supernatants infected with different HIV-1 subtypes, including subtype O. With fourth-generation assays, considerably fewer false-positive results (n = 4 to 6) were obtained, in comparison with the third-generation EIA (n = 18). Fourth-generation assays permit an earlier diagnosis of HIV infection than third-generation antibody screening assays through the detection of p24 antigen, which may be present in serum samples from individuals with recent HIV infection prior to seroconversion.     

Canalicular bile salt-independent bile formation: concepts and clues from electrolyte transport in rat liver

Studies on canalicular electrolyte transport are reviewed with reference to the concept that hepatocellular inorganic ion secretion may provide an osmotic drive for canalicular water flow. Cellular transport of electrolytes and of some nonelectrolytes appears directly or indirectly (cotransport or potential-sensitive transport) related to the activity of Na+-K+-ATPase of the sinusoidal cell membrane, but the role of the enzyme in regulating bile flow remains undetermined. Bile secretion of the isolated rat liver continues in the absence of either Na+, K+, Cl-, or HCO-3 when these ions are replaced in the perfusion medium by other permanent ions. Transepithelial salt concentration gradients, established experimentally, cause transient changes of bile flow and dissipate very quickly. Isotopic ion equilibration between sinusoids and bile proceeds faster than between sinusoids and liver cells. Both observations indicate extensive electrolyte diffusion through a paracellular shunt pathway. This pathway appears preferentially permeable to cations, and it restricts permeation of molecules of the size of sucrose (no apparent diffusion or effects of solvent drag) or bile acids (no backleak). In promoting canalicular osmotic water flow, transepithelial concentration gradients of NaCl are less effective than those of sucrose, revealing a reflection coefficient of NaCl of 0.3. By perfusion with hypertonic medium containing sucrose, bile flow is reduced. Bile production against this opposing osmotic gradient is accomplished by an increase in biliary organic anion concentration. Inorganic ion concentrations essentially conform to a Gibbs-Donnan distribution across the canalicular epithelium, established by the presence of impermeant anions in bile. Hence, the luminal electrical potential is expected to be negative with respect to the sinusoids. It is concluded that biliary secretion of endogenous organic anions is the major osmotic driving force for canalicular bile salt-independent bile flow and that transport of inorganic ions into bile results mainly from diffusion and solvent drag.     

Production and characterization of antisera specific for the erb-portion of p75, the presumptive transforming protein of avian erythroblastosis virus

The polypeptide pattern of intracytoplasmic A particles, isolated from mammary tumors of ICRC mice, displayed a prominant doublet of about 75,000 molecular weight (Ap75) and a lesser band of 42,000 molecular weight (Ap42). A particle proteins were analyzed by tryptic fingerprint mapping and compared to similarly treated core proteins (p10, p14, p23, and p28) of murine mammary tumor virus (MuMTV) purified from the milk of ICRC mice. Comparison of the peptide maps showed that almost all the major spots of the MuMTV core proteins could be located within the map of Ap75, and that Ap42 contained peptides of only p28 and p14. Since tryptic peptide maps of MuMTV core proteins have been shown to be strain-specific markers, we conclude that the A particles present in mammary tumors of ICRC mice are coded for by the same genes that code for the virions present in the milk of these mice.     

Unexplained pain conditions of the upper extremity

Diagnosis can be very difficult in the case of painful conditions of the upper extremity, since this is a region where the site of the changes and pathologic conditions precipitating or causing the pain is not always identical with the area where the pain is felt. This is particularly so in the case of pain resulting from vascular disease and irritation of peripheral nerves and in the thoracic outlet and inlet syndrome. Recent observations and studies suggest that this is extremely important for the etiology and pathogenesis of epicondylar periostitis and tendovaginitis, carpal tunnel syndrome, and some trophic conditions affecting the hand. Stenosis of the subclavian vein can be responsible for post-traumatic and postoperative edema of the hand and for similar changes whose "cause is unclear", and also for certain difficulties with wound healing. Preliminary experience suggests that Sudeck's dystrophy may be the most severe form of the thoracic outlet and inlet syndrome. Accordingly, transaxillary decompression of the neurovascular cord with upper thoracic sympathectomy can be recommended as a last resort for refractory Sudeck's dystrophy. The problem of epicondylitis of the lateral humerus is discussed in some detail, as is the pathogenesis of pain resulting from neuroma.     

Contribution to the problem of giant cell astrocytomas

Histological, immunocytochemical, and biological features of 38 giant cell gliomas were investigated. The invasion of these tumors and its giant cells by histiocytes, lymphocytes, plasma cells, and especially by eosinophilic granulocytes is viewed as an immune response, which may explain a favorable clinical course. Fifty-three percent of the patients were younger than 45 years at the time of surgery. The average postoperative survival of 27.4 months was clearly longer than in glioblastoma. These biological features suggest a differentiation from glioblastoma multiforme. The classification of this entity as "monstrocellular astrocytoma" is proposed.     

Management des blutenden Patienten mit Immunthrombozytopenie

Die Anaesthesiologie - Die Immunthrombozytopenie (ITP) ist eine seltene, erworbene Thrombozytopenie mit einer Inzidenz von 2–4/100.000 Personen und Jahr. Sie wird durch eine Thrombozytenzahl...