Clinical features of 49 episodes of Pneumocystis carinii pneumonia in patients with the acquired immunodeficiency syndrome were compared with those of 39 episodes in patients with other immunosuppressive diseases. At presentation patients with the syndrome were found to have a longer median duration of symptoms (28 days versus 5 days, p = 0.0001), lower mean respiratory rate (23.4 versus 30, p = 0.005), and higher median room air arterial oxygen tension (69 mm Hg versus 52 mm Hg, p = 0.0002). The survival rate from 1979 to 1983 was similar for the two groups (57% and 50% respectively). Patients with the syndrome had a higher incidence of adverse reactions to trimethoprim-sulfamethoxazole (22 of 34 versus 2 of 17, p = 0.0007). Survivors with the syndrome at initial presentation had a significantly lower respiratory rate, and higher room air arterial oxygen tension, lymphocyte count, and serum albumin level compared to nonsurvivors. Pneumocystis carinii pneumonia presents as a more insidious disease process in patients with the syndrome, and drug therapy in these patients is complicated by frequent adverse reactions.

The objective of the study presented here was to evaluate the relationship of adequacy of dialysis and nutritional status to mortality, technique failure, and morbidity. This was a prospective cohort study of consecutive patients commencing continuous peritoneal dialysis in 14 centers in Canada and the United States. Between September 1, 1990 and December 31, 1992, 680 patients were enrolled. Follow-up was terminated December 31, 1993. There were 90 deaths, 137 transplants, and 118 technique failures. Fifteen withdrew from dialysis. Analysis of the patient and technique survival used the Cox proportional hazards model with adequacy of dialysis and nutritional status as time-dependent covariates. The relative risk (RR) of death increased with increased age, insulin-dependent diabetes mellitus, cardiovascular disease, decreased serum albumin concentration and worsened nutritional status (subjective global assessment and percentage lean body mass). A decrease of 0.1 unit Kt/V per week was associated with a 5% increase in the RR of death; a decrease of 5 L/1.73 m2 creatinine clearance (CCr) per week was associated with a 7% increase in the RR of death. The RR of technique failure was increased with decreased albumin concentration and decreased CCr. Hospitalization was increased with decreased serum albumin concentration, worsened nutrition according to subjective global assessment and decreased CCr. A weekly Kt/V of 2.1 and a weekly CCr of 70 L/1.73 m2 were each associated with an expected 2-yr survival of 78%.

The vitamin D binding protein (DBP) is the major plasma carrier protein of vitamin D and its metabolites. Unlike other hydrophobic hormone-binding systems, it circulates in a considerably higher titer compared to its ligands. Apart from its specific sterol binding capacity, DBP exerts several other important biological functions such as actin scavenging, fatty acid transport, macrophage activation and chemotaxis. The DBP-gene is a member of a multigene cluster that includes albumin, alpha-fetoprotein, and alpha-albumin/afamin. All four genes are expressed predominantly in the liver with overlapping developmental profiles. DBP is a highly polymorphic serum protein with three common alleles (Gc1F, Gc1S and Gc2) and more than 120 rare variants. The presence of unique alleles is a useful tool for anthropological studies to discriminate and to reveal ancestral links between populations. Many studies have discussed the link between DBP-phenotypes and susceptibility or resistance to osteoporosis, Graves' disease, Hashimoto's thyroiditis, diabetes, COPD, AIDS, multiple sclerosis, sarcoidosis and rheumatic fever. This article reviews the general characteristics, functions and clinical aspects of DBP.

BACKGROUND

Among patients with end-stage renal disease who are treated with hemodialysis, solute clearance during dialysis and nutritional adequacy are determinants of mortality. We determined the effects of reductions in blood urea nitrogen concentrations during dialysis and changes in serum albumin concentrations, as an indicator of nutritional status, on mortality in a large group of patients treated with hemodialysis.

METHODS

We analyzed retrospectively the demographic characteristics, mortality rate, duration of hemodialysis, serum albumin concentration, and urea reduction ratio (defined as the percent reduction in blood urea nitrogen concentration during a single dialysis treatment) in 13,473 patients treated from October 1, 1990, through March 31, 1991. The risk of death was determined as a function of the urea reduction ratio and serum albumin concentration.

RESULTS

As compared with patients with urea reduction ratios of 65 to 69 percent, patients with values below 60 percent had a higher risk of death during follow-up (odds ratio, 1.28 for urea reduction ratios of 55 to 59 percent and 1.39 for ratios below 55 percent). Fifty-five percent of the patients had urea reduction ratios below 60 percent. The duration of dialysis was not predictive of mortality. The serum albumin concentration was a more powerful (21 times greater) predictor of death than the urea reduction ratio, and 60 percent of the patients had serum albumin concentrations predictive of an increased risk of death (values below 4.0 g per deciliter). The odds ratio for death was 1.48 for serum albumin concentrations of 3.5 to 3.9 g per deciliter and 3.13 for concentrations of 3.0 to 3.4 g per deciliter. Diabetic patients had lower serum albumin concentrations and urea reduction ratios than nondiabetic patients.

CONCLUSIONS

Low urea reduction ratios during dialysis are associated with increased odds ratios for death. These risks are worsened by inadequate nutrition.

Lysophosphatidic acid (LPA) is a water-soluble phospholipid with hormone-like and growth-factor-like activities. LPA activates a putative G-protein-coupled receptor in responsive cells, but the natural source of exogenous LPA is unknown. Here we show that LPA is present in mammalian serum in an active form (bound to albumin) at concentrations of 1-5 microM, but is not detectable in platelet-poor plasma, suggesting that LPA is produced during blood clotting. We find that thrombin activation of platelets prelabelled with [32P]Pi results in the rapid release of newly formed [32P]LPA into the extracellular environment. We conclude that LPA is a novel platelet-derived lipid mediator that may play a role in inflammatory and proliferative responses to injury.

To evaluate the hypothesis that endocrine profiles change with aging independently of specific disease states, we examined the age trends of 17 major sex hormones, metabolites, and related serum proteins in 2 large groups of adult males drawn from the Massachusetts Male Aging Study, a population-based cross-sectional survey of men aged 39-70 yr conducted in 1986-89. Group 1 consisted of 415 men who were free of obesity, alcoholism, all prescription medication, prostate problems, and chronic illness (cancer, coronary heart disease, hypertension, diabetes, and ulcer). Group 2 consisted of 1294 men who reported 1 or more of the above conditions. Each age trend was satisfactorily described by a constant percent change per yr between ages 39-70 yr. Free testosterone declined by 1.2%/yr, and albumin-bound testosterone by 1.0%/yr. Sex hormone-binding globulin (SHBG), the major serum carrier of testosterone, increased by 1.2%/yr, with the net effect that total serum testosterone declined more slowly (0.4%/yr) than the free or albumin-bound pools alone. Among the major androgens and metabolites, androstane-3 alpha,17 beta-diol (androstanediol; 0.8%/yr) and androstanediol glucuronide (0.6%/yr) declined less rapidly than free testosterone, while 5 alpha-dihydrotestosterone remained essentially constant between ages 39-70 yr. Androstenedione declined at 1.3%/yr, a rate comparable to that of free testosterone, while the adrenal androgen dehydroepiandrosterone (3.1%/yr) and its sulfate (2.2%/yr) declined 2-3 times more rapidly. The levels of testosterone, SHBG, and several androgen metabolites followed a parallel course in groups 1 and 2, remaining consistently 10-15% lower in group 2 across the age range of the study. Subgroup analyses suggested that obese subjects might be responsible for much of the group difference in androgen level. Serum concentrations of estrogens and cortisol did not change significantly with age or differ between groups. Of the pituitary gonadotropins, FSH increased at 1.9%/yr, LH increased at 1.3%/yr, and PRL declined at 0.4%/yr, with no significant difference between groups 1 and 2.(ABSTRACT TRUNCATED AT 400 WORDS)

Psoriasis is a common papulosquamous skin disease. The histopathology is characterized by epidermal hyperplasia and inflammation. Recent studies suggest that keratinocyte proliferation and inflammation in psoriasis are manifestations of the same underlying pathological process. Interleukin 6 (IL-6), a cytokine that is a major mediator of the host response to tissue injury and infection, is produced by both keratinocytes and leukocytes in culture. IL-6 expression was studied in psoriatic plaques by immunoperoxidase staining with two different polyclonal anti-recombinant IL-6 antisera and by in situ nucleic acid hybridization with IL-6 cRNA probes. Epidermal and dermal cells in active psoriatic plaques from 35 psoriasis patients stained heavily for IL-6 as compared with nonlesional skin and with plaques after treatment with antimetabolic and antiinflammatory agents. Absorption of the anti-recombinant IL-6 antisera with purified fibroblast-derived IL-6 or with recombinant IL-6, but not bovine serum albumin, removed the immunostaining. Increased levels of IL-6 were detected in the plasma of patients with active psoriasis (mean 3 ng/ml) by using two different bioassays. IL-6 production by proliferating keratinocytes was suggested by IL-6-specific immunostaining in cultured normal and psoriatic keratinocytes and by the detection of mRNA specific for IL-6 in psoriatic epidermis by in situ hybridization. IL-6 stimulated the proliferation of cultured, normal human keratinocytes as assessed by two different assays. Thus, IL-6 could directly contribute to the epidermal hyperplasia seen in psoriatic epithelium as well as affect the function of dermal inflammatory cells.

BACKGROUND

The debate over the correct perioperative fluid management is unresolved.

METHODS

The impact of two intraoperative fluid regimes on postoperative outcome was prospectively evaluated in 152 patients with an American Society of Anesthesiologists physical status of I-III who were undergoing elective intraabdominal surgery. Patients were randomly assigned to receive intraoperatively either liberal (liberal protocol group [LPG], n = 75; bolus of 10 ml/kg followed by 12 ml x kg(-1) x h(-1)) or restrictive (restrictive protocol group [RPG], n = 77; 4 ml x kg(-1) x h(-1)) amounts of lactated Ringer's solution. The primary endpoint was the number of patients who died or experienced complications. The secondary endpoints included time to initial passage of flatus and feces, duration of hospital stay, and changes in body weight, hematocrit, and albumin serum concentration in the first 3 postoperative days.

RESULTS

The number of patients with complications was lower in the RPG (P = 0.046). Patients in the LPG passed flatus and feces significantly later (flatus, median [range]: 4 [3-7] days in the LPG vs. 3 [2-7] days in the RPG; P < 0.001; feces: 6 [4-9] days in the LPG vs. 4 [3-9] days in the RPG; P < 0.001), and their postoperative hospital stay was significantly longer (9 [7-24] days in the LPG vs. 8 [6-21] days in the RPG; P = 0.01). Significantly larger increases in body weight were observed in the LPG compared with the RPG (P < 0.01). In the first 3 postoperative days, hematocrit and albumin concentrations were significantly higher in the RPG compared with the LPG.

CONCLUSIONS

In patients undergoing elective intraabdominal surgery, intraoperative use of restrictive fluid management may be advantageous because it reduces postoperative morbidity and shortens hospital stay.

OBJECTIVE

This study was designed to evaluate the association between vitamin D status and congestive heart failure (CHF).

BACKGROUND

Impaired intracellular calcium metabolism is an important factor in the pathogenesis of CHF. The etiology of CHF, however, is not well understood.

METHODS

Twenty patients age <50 years and 34 patients age>>/=50 years with New York Heart Association classes>>/=2 and 34 control subjects age>>/=50 years were recruited. N-terminal pro-atrial natriuretic peptide (NT-proANP), a predictor of CHF severity; vitamin D metabolites; and parameters of calcium metabolism were measured in fasting blood samples collected between November 2000 and March 2001.

RESULTS

Both groups of CHF patients had markedly increased serum levels of NT-proANP (p < 0.001), increased serum phosphorus levels (p < 0.001), and reduced circulating levels of both 25-hydroxyvitamin D (p < 0.001) and calcitriol (p < 0.001). Albumin-corrected calcium levels were reduced and parathyroid hormone levels were increased in the younger CHF patients compared with the controls (both p values <0.001). Moreover, parathyroid hormone levels tended to be higher in the elderly CHF patients than in the controls (p = 0.074). In a nonlinear regression analysis 25-hydroxyvitamin D and calcitriol were inversely correlated with NT-proANP (r(2) = 0.16; p < 0.001 and r(2) = 0.12; p < 0.01, respectively). The vitamin D genotype at the BmsI restriction site did not differ between the study groups.

CONCLUSIONS

The low vitamin D status can explain alterations in mineral metabolism as well as myocardial dysfunction in the CHF patients, and it may therefore be a contributing factor in the pathogenesis of CHF.

BACKGROUND

B-type natriuretic peptides have been shown to predict cardiovascular disease in apparently healthy individuals but their predictive ability for mortality and future cardiovascular events compared with C-reactive protein (CRP) and urinary albumin/creatinine ratio is unknown.

OBJECTIVE

To assess the prognostic value of the N-amino terminal fragment of the prohormone brain natriuretic peptide (NT-proBNP) vs CRP and urinary albumin/creatinine ratio in an older adult population.

METHODS

A population-based prospective study of 764 participants aged 50 to 89 years from a community in Copenhagen, Denmark, in which 658 participants provided blood and urinary samples and were examined between September 1, 1998, and January 24, 2000. Of these participants, 626 without heart or renal failure were enrolled. A subgroup of 537 had no history of cardiovascular disease at baseline. During 5 years of follow-up (to December 31, 2003), 94 participants died and 65 developed a first major cardiovascular event.

METHODS

Risk of mortality and first major cardiovascular event by baseline levels of NT-proBNP, CRP, and urinary albumin/creatinine ratio levels.

RESULTS

After adjustment for the cardiovascular risk factors of age, sex, smoking, diabetes mellitus, hypertension or ischemic heart disease, total cholesterol, and serum creatinine, the hazard ratio (HR) of mortality for values above the 80th percentile of NT-proBNP was 1.96 (95% confidence interval [CI], 1.21-3.19); for CRP, 1.46 (95% CI, 0.89-2.24); and for urinary albumin/creatinine ratio, 1.88 (95% CI, 1.18-2.98). Additional adjustment for left ventricular systolic dysfunction did not markedly attenuate the predictive value of NT-proBNP (HR, 1.82; 95% CI, 1.11-2.98). The absolute unadjusted increase in mortality risk for participants with values above the 80th percentile vs equal to or below the 80th percentile was 24.5% for NT-proBNP, 7.8% for CRP, and 19.5% for urinary albumin/creatinine ratio. The NT-proBNP levels were associated with first major cardiovascular events (nonfatal myocardial infarction, fatal coronary heart disease, unstable angina, heart failure, stroke, and transient ischemic attack) with an adjusted HR of 3.24 (95% CI, 1.80-5.79) vs 1.02 (95% CI, 0.56-1.85) for CRP and 2.32 (95% CI, 1.33-4.05) for urinary albumin/creatinine ratio when comparing participants with values above the 80th percentile with those with values equal to or below the 80th percentile.

CONCLUSIONS

Measurements of NT-proBNP provide prognostic information of mortality and first major cardiovascular events beyond traditional risk factors. NT-proBNP was a stronger risk biomarker for cardiovascular disease and death than CRP was in nonhospitalized individuals aged 50 to 89 years.

Age-related macular degeneration (AMD) is the leading cause of central vision loss worldwide. Drusen accumulation is the major pathological hallmark common to both dry and wet AMD. Although activation of the immune system has been implicated in disease progression, the pathways involved are unclear. Here we show that drusen isolated from donor AMD eyes activates the NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome, causing secretion of interleukin-1b (IL-1b) and IL-18. Drusen component C1Q also activates the NLRP3 inflammasome. Moreover, the oxidative-stress-related protein-modification carboxyethylpyrrole (CEP), a biomarker of AMD, primes the inflammasome. We found cleaved caspase-1 and NLRP3 in activated macrophages in the retinas of mice immunized with CEP-adducted mouse serum albumin, modeling a dry-AMD–like pathology. We show that laser-induced choroidal neovascularization (CNV), a mouse model of wet AMD, is exacerbated in Nlrp3(-/-) but not Il1r1(-/-) mice, directly implicating IL-18 in the regulation of CNV development. These findings indicate a protective role for NLRP3 and IL-18 in the progression of AMD.

The physiological alpha-oxoaldehyde methylglyoxal binds and modifies arginine, lysine, and cysteine residues in proteins. The kinetics and mechanism of these reactions were investigated with N alpha-acetylamino acids and bovine serum albumin at pH 7.4 and 37 degrees C. The reaction of methylglyoxal with N alpha-acetylarginine involved the initial reversible formation of glycosylamine and 4,5-dihydroxy-5-methylimidazolidine derivatives, with further slow irreversible conversion to an imidazolone, N alpha-acetyl-N delta- (5-methyl-4-imidazolon-2-yl)ornithine. The imidazolone was fluorescent with an excitation lambda max value of 320 nm and an emission lambda max value of 398 nm. Methylglyoxal reacted reversibly with N alpha-acetyllysine to form glycosylamine and bisglycosylamine derivatives. Further reaction of these glycosylamines occurred to form brown, fluorescent oligomers that were not characterized. Methylglyoxal reacted rapidly and reversibly with N alpha-acetylcysteine to form the hemithioacetal adduct. The reaction of methylglyoxal with bovine serum albumin (BSA) at pH 7.4 and 37 degrees C involved the reversible and irreversible formation of methylglyoxal-BSA adducts. Irreversible modification of BSA occurred mainly on arginine residues to form imidazolone. The formation of methylglyoxal-modified proteins involves glycoxidation leading to advanced glycation end product-like fluorescence. It is expected to be increased in diabetes mellitus and may be linked to the development of diabetic complications.

Triangular silver nanoparticles ( approximately 100 nm wide and 50 nm high) have remarkable optical properties. In particular, the peak extinction wavelength, lambda(max) of their localized surface plasmon resonance (LSPR) spectrum is unexpectedly sensitive to nanoparticle size, shape, and local ( approximately 10-30 nm) external dielectric environment. This sensitivity of the LSPR lambda(max) to the nanoenvironment has allowed us to develop a new class of nanoscale affinity biosensors. The essential characteristics and operational principles of these LSPR nanobiosensors will be illustrated using the well-studied biotin-streptavidin system. Exposure of biotin-functionalized Ag nanotriangles to 100 nM streptavidin (SA) caused a 27.0 nm red-shift in the LSPR lambda(max). The LSPR lambda(max) shift, DeltaR/DeltaR(max), versus [SA] response curve was measured over the concentration range 10(-)(15) M < [SA] < 10(-)(6) M. Comparison of the data with the theoretical normalized response expected for 1:1 binding of a ligand to a multivalent receptor with different sites but invariant affinities yielded approximate values for the saturation response, DeltaR(max) = 26.5 nm, and the surface-confined thermodynamic binding constant K(a,surf) = 10(11) M(-)(1). At present, the limit of detection (LOD) for the LSPR nanobiosensor is found to be in the low-picomolar to high-femtomolar region. A strategy to amplify the response of the LSPR nanobiosensor using biotinylated Au colloids and thereby further improve the LOD is demonstrated. Several control experiments were performed to define the LSPR nanobiosensor's response to nonspecific binding as well as to demonstrate its response to the specific binding of another protein. These include the following: (1) electrostatic binding of SA to a nonbiotinylated surface, (2) nonspecific interactions of prebiotinylated SA to a biotinylated surface, (3) nonspecific interactions of bovine serum albumin to a biotinylated surface, and (4) specific binding of anti-biotin to a biotinylated surface. The LSPR nanobiosensor provides a pathway to ultrasensitive biodetection experiments with extremely simple, small, light, robust, low-cost instrumentation that will greatly facilitate field-portable environmental or point-of-service medical diagnostic applications.

BACKGROUND

Although several studies compare surgical results of laparoscopic and open colonic resections, there is no study of laparoscopic gastrectomy compared with open gastrectomy.

OBJECTIVE

When compared with conventional open gastrectomy, laparoscopy-assisted Billroth I gastrectomy is less invasive in patients with early-stage gastric cancer.

METHODS

Retrospective review of operative data, blood analyses, and postoperative clinical course after Billroth I gastrectomy.

METHODS

University hospital in Japan.

METHODS

The study included 102 patients who were treated with Billroth I gastrectomy for early-stage gastric cancer from January 1993 to July 1999: 49 with laparoscopy-assisted gastrectomy and 53 with conventional open gastrectomy.

METHODS

Demographic features examined were operation time; blood loss; blood cell counts of leukocytes, granulocytes, and lymphocytes; serum levels of C-reactive protein, interleukin 6, total protein, and albumin; body temperature; weight loss; analgesic requirements; time to first flatus; time to liquid diet; length of postoperative hospital stay; complications; proximal margin of the resected stomach; and number of harvested lymph nodes.

RESULTS

Significant differences (P<.05) were present between laparoscopy-assisted and conventional open gastrectomy when the following features were compared: blood loss (158 vs 302 mL), leukocyte count on day 1 (9.42 vs 11.14 x 10(9)/L) and day 3 (6.99 vs 8.22 x 10(9)/L), granulocyte count on day 1 (7.28 vs 8.90 x 10(9)/L), C-reactive protein level on day 7 (2.91 vs 5.19 mg/dL), interleukin 6 level on day 3 (4.2 vs 26.0 U/mL), serum albumin level on day 7 (35.6 vs 33.9 g/L), number of times analgesics given (3.3 vs 6.2), time to first flatus (3.9 vs 4.5 days), time to liquid diet (5.0 vs 5.7 days), postoperative hospital stay (17.6 vs 22.5 days), and weight loss on day 14 (5.5% vs 7.1%). There was no significant difference between laparoscopy-assisted and conventional open gastrectomy with regard to operation time (246 vs 228 minutes), proximal margin (6.2 vs 6.0 cm), number of harvested lymph nodes (18.4 vs 22.1), and complication rate (8% vs 21%).

CONCLUSIONS

Laparoscopy-assisted Billroth I gastrectomy, when compared with conventional open gastrectomy, has several advantages, including less surgical trauma, less impaired nutrition, less pain, rapid return of gastrointestinal function, and shorter hospital stay, with no decrease in operative curability. When performed by a skilled surgeon, laparoscopy-assisted Billroth I gastrectomy is a safe and useful technique for patients with early-stage gastric cancer.

BACKGROUND

Despite the availability of potent antibiotics and intensive care, mortality rates from septic shock are 40-70%. We assessed the safety and efficacy of murine monoclonal antibody to human tumour necrosis factor alpha (TNF alpha MAb) in the treatment of septic shock.

METHODS

In a randomised, multicentre, double-blind, placebo-controlled clinical trial in 105 hospitals in the USA and Canada, we randomly assigned 1879 patients a single infusion of 7.5 mg/kg TNF alpha MAb (n=949) or placebo (0.25% human serum albumin n=930). Our main outcome measurement was the rate of all-cause mortality at 28 days.

RESULTS

382 (40.3%) of 948 patients who received TNF alpha MAb and 398 (42.8%) of 930 who received placebo had died at 28 days (95% CI -0.02 to 0.07, p=0.27). We found no association between therapy with TNF alpha MAb and increased rapidity in reversal of initial shock or prevention of subsequent shock. Similarly, baseline plasma interleukin-6 concentrations of more than 1000 pg/mL or detectable circulating TNF concentrations were not associated with improvement in survival after TNF alpha MAb therapy. Coagulopathy but not other organ or system failures, was significantly decreased in the TNF alpha MAb group compared with placebo (day 7, p<0.001; day 28, p=0.005). Serious adverse events were reported in 55.2% of patients given placebo and 54.1% in the TNF alpha MAb group.

CONCLUSIONS

We did not find an improvement in survival after septic shock with TNF alpha MAb. Therapy not solely dependent on TNF alpha blockade may be required to improve survival.

A sensitive and specific radioimmunoassay for adenosine 3',5'-cyclic phosphate (cyclic AMP) has been developed which allows measurement of the nucleotide in extracts of 5-10 mg of tissue. The radioimmunoassay is sufficiently specific for cyclic AMP to eliminate the need for prior chromatographic separation of the cyclic nucleotide from other tissue nucleotides. The radioimmunoassay system is based upon competition of cyclic AMP with a labeled cyclic AMP derivative of high specific activity for binding sites on an antibody specific for the cyclic nucleotide. Antibody to cyclic AMP was obtained by immunizing rabbits with an antigen prepared by conjugating succinyl cyclic AMP with human serum albumin. A high specific activity derivative of cyclic AMP was prepared by synthesizing succinyl cyclic AMP tyrosine methyl ester (SCAMP-TME) and iodinating the phenolic hydroxyl group of the tyrosine moiety with (125)I. Free and antibody-bound (125)I-SCAMP-TME were separated by precipitation of the antibody-bound fraction with a second antibody (goat anti-rabbit gamma globulin). Displacement of (125)I-SCAMP-TME by unlabeled cyclic AMP when plotted as a semilogarithmic function was linear over a concentration range of 2-100 picomoles. The specificity of the antibody was tested against structurally related nucleotides, nucleosides, and purine bases. All had less than 0.005 per cent of the potency of cyclic AMP in inhibiting (125)I-SCAMP-TME binding. The marked differences in affinity of the various cyclic nucleotides to cyclic AMP antibody would suggest that antibodies can be developed for each of the cyclic nucleotides by the principles used in this work.

Methoxypolyethylene glycols of 1900 and 5000 daltons have been attached covalently to bovine serum albumin using cyanuric chloride as the coupling agent. When sufficient polymer is attached, the modified bovine serum albumin appears to lose its immunogenicity in the rabbit and, on intramuscular or intravenous injection, elicits antibodies neither to itself nor to native bovine serum albumin. It does not react with antibodies raised against native bovine serum albumin. Bovine serum albumin to which methoxypolyethylene glycol has been attached exhibits a blood circulating life in the rabbit rather similar to native bovine serum albumin, except that it is not removed from circulation by the eventual development of antibodies. Modified bovine serum albumins which had been iodinated with 125I, or prepared with [14C]cyanuric chloride, were injected intravenously in rabbits. Both labels appeared almost quantitatively in the urine after 30 days. The modified bovine serum albumins showed substantial changes in properties, such as solubility, electrophoretic mobility in acrylamide gel, ion exchange chromatography, and sedimentation, as compared with the unmodified protein.

To explore the effect of the acquired immunodeficiency syndrome on gastrointestinal structure and absorption, the cases of 12 homosexual men with the syndrome and 11 homosexual controls were studied. Seven patients had diarrhea with weight loss. Bacterial or parasitic infections were not detected. All patients were malnourished; had significantly fewer T-lymphocyte helper and suppressor cells; and had significantly lower body weights, midarm circumferences, serum albumin concentrations, and iron binding capacities than homosexual controls. D-Xylose malabsorption and steatorrhea were present in patients, especially those with diarrhea. Jejunal and rectal biopsy samples were histologically abnormal in all patients with diarrhea. Jejunal abnormalities included partial villus atrophy with crypt hyperplasia and increased numbers of intraepithelial lymphocytes. Rectal abnormalities included intranuclear viral inclusions, mast cell infiltration in the lamina propria, and focal cell degeneration near the crypt base. The histologic findings suggest that a specific pathologic process occurs in the lamina propria of the small intestine and colon in some patients with the syndrome.

Serum induces Candida albicans to make a rapid morphological change from the yeast cell form to hyphae. Contrary to the previous reports, we found that serum albumin does not play a critical role in this morphological change. Instead, a filtrate (molecular mass, <1 kDa) devoid of serum albumin induces hyphae. To study genes controlling this response, we have isolated the RAS1 gene from C. albicans by complementation. The Candida Ras1 protein, like Ras1 and Ras2 of Saccharomyces cerevisiae, has a long C-terminal extension. Although RAS1 appears to be the only RAS gene present in the C. albicans genome, strains homozygous for a deletion of RAS1 (ras1-2/ras1-3) are viable. The Candida ras1-2/ras1-3 mutant fails to form germ tubes and hyphae in response to serum or to a serum filtrate but does form pseudohyphae. Moreover, strains expressing the dominant active RAS1(V13) allele manifest enhanced hyphal growth, whereas those expressing a dominant negative RAS1(A16) allele show reduced hyphal growth. These data show that low-molecular-weight molecules in serum induce hyphal differentiation in C. albicans through a Ras-mediated signal transduction pathway.

Protein adhesion plays a major role in determining the biocompatibility of materials. The first stage of implant integration is the adhesion of protein followed by cell attachment. Surface modification of implants (surface chemistry and topography) to induce and control protein and cell adhesion is currently of great interest. This communication presents data on protein adsorption (bovine serum albumin and fibrinogen) onto model hydrophobic (CH(3)) and hydrophilic (OH) surfaces, investigated using a quartz crystal microbalance (QCM) and grazing angle infrared spectroscopy. Our data suggest that albumin undergoes adsorption via a single step whereas fibrinogen adsorption is a more complex, multistage process. Albumin has a stronger affinity toward the CH(3) compared to OH terminated surface. In contrast, fibrinogen adheres more rapidly to both surfaces, having a slightly higher affinity toward the hydrophobic surface. Conformational assessment of the adsorbed proteins by grazing angle infrared spectroscopy (GA-FTIR) shows that after an initial 1 h incubation few further time-dependent changes are observed. Both proteins exhibited a less organized secondary structure upon adsorption onto a hydrophobic surface than onto a hydrophilic surface, with the effect observed greatest for albumin. This study demonstrates the ability of simple tailor-made monochemical surfaces to influence binding rates and conformation of bound proteins through protein-surface interactions. Current interest in biocompatible materials has focused on surface modifications to induce rapid healing, both of implants and for wound care products. This effect may also be of significance at the next stage of implant integration, as cell adhesion occurs through the surface protein layer.

In the accompanying report (Visconti, P.E., Bailey, J.L., Moore, G.D., Pan, D., Olds-Clarke, P. and Kopf, G.S. (1995) Development, 121, 1129-1137) we demonstrated that the tyrosine phosphorylation of a subset of mouse sperm proteins of M(r) 40,000-120,000 was correlated with the capacitation state of the sperm. The mechanism by which protein tyrosine phosphorylation is regulated in sperm during this process is the subject of this report. Cauda epididymal sperm, when incubated in media devoid of NaHCO3, CaCl2 or bovine serum albumin do not display the capacitation-associated increases in protein tyrosine phosphorylation of this subset of proteins. This NaHCO3, CaCl2 or bovine serum albumin requirement for protein tyrosine phosphorylation can be completely overcome by the addition of biologically active, but not inactive, cAMP analogues. Addition of the active cAMP analogues to sperm incubated in media devoid of NaHCO3, CaCl2 or bovine serum albumin overcomes the inability of these media to support capacitation, as assessed by the ability of the cells to acquire the pattern B chlortetracycline fluorescence, to undergo the zona pellucida-induced acrosome reaction and, in some cases, to fertilize metaphase II-arrested eggs in vitro. The effects of the cAMP analogues to enhance protein tyrosine phosphorylation and to promote capacitation appears to be at the level of the cAMP-dependent protein kinase (PKA), since two specific inhibitors of this enzyme (H-89 and Rp-cAMPS) block the capacitation-dependent increases in protein tyrosine phosphorylation in sperm incubated in media supporting capacitation. Capacitation, as assessed by the aforementioned endpoints, also appears to be inhibited by H-89 in a concentration-dependent manner. These results provide further evidence for the interrelationship between protein tyrosine phosphorylation and the appearance of the capacitated state in mouse sperm. They also demonstrate that both protein tyrosine phosphorylation and capacitation appear to be regulated by cAMP/PKA. Up-regulation of protein tyrosine phosphorylation by cAMP/PKA in sperm is, to our knowledge, the first demonstration of such an interrelationship between tyrosine kinase/phosphatase and PKA signaling pathways.

Some risk factors for coronary heart disease (CHD) incidence in the general population are not associated with CHD incidence among patients with ESRD but have not been well characterized in chronic kidney disease (CKD). The association of several risk factors with CHD incidence was studied among participants with CKD in the population-based Atherosclerosis Risk in Communities (ARIC) Study. CHD risk factors and estimated GFR using serum creatinine were measured among 807 ARIC participants with CKD (estimated GFR between 15 and 59 ml/min per 1.73 m(2)). The incidence of CHD during 10.5 yr of follow-up was 6.3, 8.5, and 14.4 per 1000 person-years among ARIC participants with an estimated GFR of>>/=90, 60 to 89, and 15 to 59 ml/min per 1.73 m(2), respectively. After adjustment for age, race, gender, and ARIC field center, among those with CKD, the relative risk (95% confidence interval) of CHD was 1.65 (1.01 to 2.67) for current smoking, 2.02 (1.27 to 3.22) for hypertension, 3.06 (2.01 to 4.67) for diabetes, and 1.96 (1.14 to 3.36) for anemia. The comparably adjusted relative risks of CHD for each standard deviation higher total and HDL cholesterol were 1.50 (1.25 to 1.71) and 0.79 (0.62 to 1.01), respectively, and 1.38 (1.13 to 1.69), 1.24 (1.06 to 1.46), 0.65 (0.54 to 0.79), and 1.38 (1.19 to 1.59) for waist circumference, leukocyte count, serum albumin, and fibrinogen, respectively. CHD risk factors in the general population remain predictive among patients with CKD. Given the high risk for CHD among patients with CKD, control of these risk factors may have a substantial impact on their excess burden of CHD.

Sirtuins are homologues of the yeast transcriptional repressor Sir2p and are conserved from bacteria to humans. We report that human SIRT4 is localized to the mitochondria. SIRT4 is a matrix protein and becomes cleaved at amino acid 28 after import into mitochondria. Mass spectrometry analysis of proteins that coimmunoprecipitate with SIRT4 identified insulindegrading enzyme and the ADP/ATP carrier proteins, ANT2 and ANT3. SIRT4 exhibits no histone deacetylase activity but functions as an efficient ADP-ribosyltransferase on histones and bovine serum albumin. SIRT4 is expressed in islets of Langerhans and colocalizes with insulin-expressing beta cells. Depletion of SIRT4 from insulin-producing INS-1E cells results in increased insulin secretion in response to glucose. These observations define a new role for mitochondrial SIRT4 in the regulation of insulin secretion.

We here report nine liver cirrhosis (LC) patients that underwent autologous bone marrow cell infusion (ABMI) from the peripheral vein. Subjects were patients with LC with total bilirubin of less than 3.0 mg/dl, platelet count of more than 5 (10(10)/l), and no viable hepatocellular carcinoma on diagnostic imaging. Autologous bone marrow (BM; 400 ml) was isolated from the ilium under general anesthesia. Mononuclear cells (MNCs) were separated by cell washing and were infused via the peripheral vein. MNC characteristics were confirmed by fluorescence-activated cell sorting analysis (CD34, CD45, and c-kit). After ABMI therapy, liver function was monitored by blood examination for 24 weeks. From 400 ml of BM, we obtained 7.81 +/- 0.98 x 10(9) MNCs. After washing, 5.20 +/- 0.63 x 10(9) MNCs were infused into patients with LC. Significant improvements in serum albumin levels and total protein were observed at 24 weeks after ABMI therapy (p < .05). Significantly improved Child-Pugh scores were seen at 4 and 24 weeks (p < .05). alpha-Fetoprotein and proliferating cell nuclear antigen (PCNA) expression in liver biopsy tissue was significantly elevated after ABMI therapy (p < .05). No major adverse effects were noted. In conclusion, ABMI therapy should be considered as a novel treatment for patients with decompensated LC.