What proteins are present in polyethylene glycol precipitates from rheumatic sera?

The proteins present in 4% polyethylene glycol (PEG) precipitates of 10 normal sera and 60 samples from patients with rheumatic diseases were studied. A variety of immunochemical methods were used, including estimation of the percentages of total serum proteins precipitated by PEG, gel filtration analyses of the precipitates, and affinity chromatography with protein A and anti-immunoglobulin columns. Substantial amounts of protein were precipitated from normal sera. Many non-immunoglobulin proteins were precipitated from patients' sera, including fibronectin, haptoglobin, albumin, transferrin, and alpha 1-antitrypsin. Affinity chromatography with anti-immunoglobulin columns bound non-immunoglobulin proteins from PEG precipitates, but the protein A affinity column did not do so. The view that circulating antibody-antigen complexes alone are precipitated by 4% PEG is too simplistic; many non-immunoglobulin proteins are involved. They may either bind to immune complexes or be coprecipitated owing to non-specific protein aggregation.     

Identification of Alcohol Abuse and Alcoholism with Biological Parameters

The prevalence and incidence of heavy alcohol consumption are major problems which have been increasing in many countries in recent years. It is crucial for physicians to consistently identify early drinking problems as well as the various end disease states in order to minimize suffering and maximize recovery. This paper reviews the evolutionary development of clinical tools for detection of alcohol abuse. The focus is primarily on clinical/biochemical indicators of alcohol abuse, emphasizing but not limited to changes in hematological characteristics, liver enzyme activity, lipids, immune function factors, hormones, neurological factors, and some physically based tests. Use of test combinations and sophisticated statistical analysis of pattern changes in test batteries evidence increased diagnostic efficiency.     

Acute ischemic stroke review.

More than 700,000 people have a stroke each year in the United States. A diagnosis of stroke formerly elicited a nihilistic approach, but this has substantially changed in the last decade. Currently, time is brain, and it is important for all disciplines to work together to initiate acute stroke protocols in the emergency department and identify patients within the therapeutic time window for thrombolytic and neuroprotective therapies. Evolving protocols, management, and nursing care all have important implications during the acute phase of ischemic stroke. Patient and family education on risk reduction must also be addressed by the entire healthcare team.     

Characterization of guanylate cyclase in squid photoreceptors

Light causes a rapid, 1.7-fold increase in cyclic GMP concentration in intact squid retinas (Johnson et al. (1986]. To determine whether light-induced changes in cyclic GMP concentration result from activation of guanylate cyclase, we have studied the regulation of guanylate cyclase activity in squid (Loligo pealei) photoreceptors. The enzyme is membrane-associated and activity is enhanced by the detergents Triton X-100 or digitonin. The enzyme requires divalent cations, Mn2+ being preferred over Mg2+. The dependence of enzyme activity on the MnGTP concentration deviates from simple Michaelis-Menten kinetics. Under conditions where a light-induced binding of GTP to the guanine nucleotide regulatory protein can be observed, no light-induced change in guanylate cyclase could be detected.