Alterations in interleukin-4 and antibody production following pheromone exposure: role of glucocorticoids

We have previously shown that exposure to pheromones from footshock-stressed mice suppresses cell-mediated immunity and enhances humoral immunity. Here we show that stress odor exposure is associated with enhanced antigen-specific antibody production and interleukin (IL)-4 production in BALB/c, but not C57Bl/6, mice. Glucocorticoid receptor antagonism blocks the enhancement of IL-4, but not antibody titers. There is an apparent differential sensitivity of BALB/c and C57Bl/6 spleen cells to in vitro incubation with the synthetic glucocorticoid dexamethasone; IL-2 production by BALB/c spleen cells is more sensitive to the effects of steroid. These data suggest that C57Bl/6 mice may not respond to stress pheromones due to their relative insensitivity to endogenous steroids.

Pavlovian conditioning of the immune system

In the classical Pavlovian conditioning paradigm, a stimulus that unconditionally elicits a physiological response is repeatedly paired with a neutral stimulus that does not elicit that same response. Eventually, the neutral stimulus becomes a conditioned stimulus in that it elicits the physiological response in the absence of an unconditioned stimulus. Here we summarize experiments in which Pavlovian conditioning has revealed an intimate relationship between the central nervous system and the immune system.

Similar immune response to nonlethal infection with herpes simplex virus-1 in sensitive (BALB/c) and resistant (C57BL/6) strains of mice

Previous investigations have demonstrated a strain-associated differential susceptibility to herpes simplex virus-1 (HSV-1) infection in mice; C57BL/6 mice are more resistant to infection than BALB/c mice. Despite considerable research dealing with the immune response to HSV-1, relatively little attention has been paid to differences in immune responses between strains with different sensitivities to the virus. Here we report that immune responses (i.e., cytokine profiles, CTL activity, serum antibody, and natural killer cell activity) following footpad infection with a sublethal dose of HSV-1 do not substantially differ between the two strains. It is notable that C57BL/6 mice are also more resistant than BALB/c mice to other pathogens, including Leishmania, and this resistance is associated with a predominant TH1 response in C57BL/6 mice versus a predominant TH2 response in BALB/c mice. However, unlike several other pathogens, the increased susceptibility to HSV-1 infection of BALB/c mice, compared to C57BL/6 mice, does not appear to involve an obvious difference in the TH1 vs TH2 dominance of the immune response to this virus.

[Hemodynamic effects of chronic treatment by cilazapril in normotensive patients with obliterative arterial diseases of the lower limbs]

OBJECTIVE

To determine whether long-term treatment with cilazapril (CIL) may improve pulse pressure (PP), arterial compliance and ankle-arm systolic index (AAI) in patients with lower-extremity arterial disease (LEAD). Indeed, in both systolic hypertension and LEAD, the increase in pulse pressure has been attributed to a reduced compliance.

DESIGN AND METHODS

Thirteen patients (age: 65 +/- 5 yrs; AAI: 0.78 +/- 0.15; m +/- SD) were included in a double-blind randomized parallel study to compare the effects of a 6 month treatment with CIL (10 mg per day; n = 6) to those of placebo (PL; n = 7) Blood pressure, AAI and arterial compliance were determined at baseline (MO) and after 3 (M3) and 6 months (M6). Common carotid (CC) and common femoral (CF) artery compliances were noninvasively determined from pulsatile changes in arterial diameter (Wall Track System, Hoeks et al., 1990) and pressure (PP).

RESULTS

Both groups were comparable at MO. Compared to PL, CIL significantly reduced PP (-22 +/- 4 vs -2 +/- 9 mmHg) and MAP (-16 +/- 11 vs -4 +/- 7 mmHg) and improved CC (+54 +/- 34 vs +5 +/- 21 mm2.mmHg-1.10(-3)) at M6. Weaker effects were observed at M3. No significant changes in AAI and CF compliance were observed.

CONCLUSIONS

A direct effect of CIL on the large artery wall was suggested by 1) a greater reduction in PP than in MAP and 2) a disproportionately greater improvement in CC compliance compared with the reduction in distending pressure (MAP). These results indicate that long-term treatment with CIL may improve large artery function in patients with LEAD.

The algorithmic complexity of neural spike trains increases during focal seizures

The interspike interval spike trains of spontaneously active cortical neurons can display nonrandom internal structure. The degree of nonrandom structure can be quantified and was found to decrease during focal epileptic seizures. Greater statistical discrimination between the two physiological conditions (normal vs seizure) was obtained with measurements of context-free grammar complexity than by measures of the distribution of the interspike intervals such as the mean interval, its standard deviation, skewness, or kurtosis. An examination of fixed epoch data sets showed that two factors contribute to the complexity: the firing rate and the internal structure of the spike train. However, calculations with randomly shuffled surrogates of the original data sets showed that the complexity is not completely determined by the firing rate. The sequence-sensitive structure of the spike train is a significant contributor. By combining complexity measurements with statistically related surrogate data sets, it is possible to classify neurons according to the dynamical structure of their spike trains. This classification could not have been made on the basis of conventional distribution-determined measures. Computations with more sophisticated kinds of surrogate data show that the structure observed using complexity measures cannot be attributed to linearly correlated noise or to linearly correlated noise transformed by a static monotonic nonlinearity. The patterns in spike trains appear to reflect genuine nonlinear structure. The limitations of these results are also discussed. The results presented in this article do not, of themselves, establish the presence of a fine-structure encoding of neural information.

Physician use of a computerized medical record system during the patient encounter: a descriptive study

The computerized medical record program, CLINIC, specifically designed at Ben-Gurion University of the Negev to be used on-line in a primary care clinic during a patient encounter by healthcare professionals, has been in use for over 6 years in two community clinics. In order to analyse the effectiveness and use of CLINIC, four physicians were video recorded during working sessions before and after the introduction of CLINIC. While using CLINIC did not change the total mean encounter time, the lengths of the encounter components and record use did change. The physicians' work style changed from a 'conversational pattern' (continuous data recording) to a 'blocked pattern' (data entry at intervals).

Nonradioactive screening of glucokinase mutations in maturity onset diabetes of the young

DNA mutations were previously identified in the glucokinase gene in 56% of French families affected with maturity onset diabetes of the young (MODY), an early onset autosomal dominant form of non-insulin-dependent diabetes mellitus (NIDDM). Mutations were found on almost all exons using the common radioactive single-strand conformation polymorphism (SSCP) technique. In this paper, we describe a non-isotopic SSCP method using the Pharmacia Biotech PhastSystem for the routine screening of new mutations in diabetic patients or in offsprings of diabetic patients. The use of the PhastSystem allowed us to easily and reproducibly optimize the electrophoretic conditions for each exon. We demonstrate the efficiency of this technique by identifying 8 mutations, 7 of which have never previously been detected, in patients referred to us for diagnostic purposes. It appears to be a sensible, easy and reliable method to improve the routine diagnosis of MODY in diabetic subjects or relatives and should be applicable to other genetic diseases.

Six mutations in the glucokinase gene identified in MODY by using a nonradioactive sensitive screening technique

We have reported that 56% of French families with maturity-onset diabetes of the young (MODY) carry a mutation in the glucokinase gene (GCK). Therefore, we have established a quick and sensitive nonradioactive technique (with the PhastSystem based on single-strand conformation polymorphism [SSCP] analysis) to routinely screen the 12 exons of GCK for mutations. We have studied GCK in 12 young hyperglycemic patients with a strong family history of type II diabetes. SSCP variants were observed in 6 of those 12 patients (50%), which cosegregated with diabetes in five families where DNA from additional members was available. Direct sequencing identified a 10-bp (base pair) deletion in exon 3; a 33-bp deletion at the exon 5/intron 5 junction, including the two consensus bases (GT) of the donor splice site; a nonsense mutation in exon 5 (Arg186-->Stop) in a Black-African family, which has been identified previously in a Caucasian family; and three missense mutations: Thr209-->Met209 in exon 6, Gly261-->Glu261 in exon 7, and Arg36-->Trp36 in exon 2. The missense mutation in exon 2 was found only in the second and third generation of the tested family but not in the first. To our knowledge, this is the first time that a de novo mutation of GCK is reported within a family. All six families carrying a mutation in GCK were typical MODY and most of their affected members had a mild form of diabetes. This nonradioactive SSCP technique may be useful to routinely diagnose glucokinase deficiency, which is an important cause of hyperglycemia among young type II diabetic patients.

Mitogen-activated axolotl (Ambystoma mexicanum) splenocytes produce a cytokine that promotes growth of homologous lymphoblasts

Culture supernatants (PHA-SNs) from axolotl splenocytes cultured with phytohemagglutinin-P (PHA) in medium supplemented with bovine serum albumin (BSA) were collected after 1, 2, and 3 days, pooled, treated to remove residual PHA, precipitated with saturated ammonium sulfate, dialyzed, aliquoted, and stored at -20 degrees C. PHA-SNs stimulated proliferation of homologous lymphoblasts, but not resting splenocytes. SDS-PAGE of metabolically labeled PHA-SNs revealed a band between 14 and 21 kDa. This corresponds to the M(r) of the gel fractions with biological stimulatory activity eluted from PHA-SNs. Blasts absorbed significant bioactivity of PHA-SNs whereas freshly harvested splenocytes did not. Although splenocytes cultured in medium supplemented with 1% fetal bovine serum (FBS) did not proliferate in response to PHA, they did secrete a cytokine with lymphoblast growth-promoting activity. Furthermore, PHA-induced lymphoblasts, initially cultured in medium supplemented with 0.25% BSA, could proliferate in response to PHA-SNs in 1% FBS-supplemented medium.

Insertion/deletion polymorphism of the angiotensin-converting enzyme gene is strongly associated with coronary heart disease in non-insulin-dependent diabetes mellitus

Non-insulin-dependent diabetes mellitus (NIDDM) is considered a model of premature atherosclerosis with a strong genetic component. We have investigated the role of angiotensin-converting enzyme (ACE; EC 3.4.15.1) gene in 316 unrelated NIDDM individuals, 132 who had myocardial infarction or significant coronary stenoses and 184 with no history of coronary heart disease (CHD). A deletion-polymorphism in the ACE gene was recently reported to be associated with myocardial infarction especially in people classified as low risk. Here we report that the D allele of the ACE gene is a strong and independent risk factor for CHD in NIDDM patients. The D allele is associated with early-onset CHD in NIDDM, independently of hypertension and lipid values. A progressively increasing relative risk in individuals heterozygous and homozygous for the D allele was observed (odds ratios of 1.41 and 2.35, respectively; P < 0.007), suggesting a codominant effect on the cardiovascular risk. The percentage of CHD attributable to the ACE deletion allele was 24% in this NIDDM population. Identification of NIDDM patients carrying this putative CHD-susceptibility genotype would help early detection and treatment of CHD.

[Bronchiolitis obliterans organizing pneumonia]

Bronchiolitis obliterans organizing pneumonia (BOOP) is an uncommon condition of unknown etiology which often responds to corticosteroids. It is characterized by cough, patchy pulmonary infiltrations and intra-alveolar organizing fibrosis. We report a 45-year-old man and a 70-year-old woman with BOOP and elevated liver enzymes. Corticosteroid therapy led to complete recovery.

Relationship between renal mass and atrial natriuretic peptide release. 2. Acute effects of various degrees of renal damage on atrial natriuretic peptide release in rats

We studied basal serum atrial natriuretic peptide (ANP) levels and the response to acute salt loading in rats with different grades of functional renal mass reduction. The six groups of rats studied included 2 controls, i.e. unoperated (n = 12) and sham-operated (n = 24) groups. Each of the 4 experimental groups (n = 24 in each) underwent one of the following procedures: bilateral nephrectomy; unilateral nephrectomy; bilateral ureteral ligation; unilateral ureteral ligation. Basal ANP was assessed in the intact controls and operated groups 4, 8, 16 and 24 h after surgery. In addition, ANP was determined in the sham-operated controls and in the experimental groups 1 h following acute intravenous saline loading performed 4 h after surgery with central venous pressure monitoring. Basal ANP dropped significantly following bilateral nephrectomy but was not significantly altered after unilateral nephrectomy or the two modalities of ureteral ligation. In all 4 experimental groups ANP failed to rise after saline loading. We conclude that substantial renal damage results in early impairment in ANP secretion suggesting the existence of a renal physiological stimulus controlling ANP release by cardiac atria.

Cavernous angiomas of the internal auditory canal. A case report and review of literature

Cavernous angiomas of the internal auditory canal (IAC) are rare. They are angiographically occult; and because the clinical symptoms are similar both in intracanalicular cavernous angiomas and acoustic tumors it had been difficult to differentiate pre-operatively both of these pathologies until the advent of magnetic resonance imaging (MRI). Even nowadays the correct diagnosis may be missed if the patient is imaged only with gadolinium enhanced MRI without prior obtaining a non-contrast MRI. These diagnostic difficulties are illustrated by the report of a related case. The importance of thorough neuroradiological investigations stressed and MRI features, surgical management and relevant literature concerning the cavernous angiomas of the internal auditory canal are discussed.

Relationship between renal mass and atrial natriuretic peptide release. 1. Paradoxical effect of unilateral nephrectomy on serum atrial natriuretic peptide in rats

Serial serum atrial natriuretic peptide (ANP) determinations were performed in 15 uninephrectomized Charles River rats and in 15 sham-operated control animals during the 60 days following surgery. In a second group of 7 control and 7 uninephrectomized animals, housed in metabolism cages, serum ANP, body weight, 24-hour urine volume, osmolality and sodium excretion were serially measured. In a third group of uninephrectomized and control rats the effect of acute salt loading 24 h, 6 and 60 days after surgery on serum ANP was studied. No significant changes in ANP levels were observed during the 60 days following surgery in control animals. In the uninephrectomized animals a sharp drop in basal ANP levels was evident 24 and 48 h after surgery, but increased levels of serum ANP were seen from day 6 to 28. Thereafter ANP returned to baseline levels for the rest of the study period. Urinary sodium excretion decreased in the nephrectomized animals on days 1 and 2 following surgery. No such change was seen in the control animals during the same period. Body weight, 24-hour urine volume and urine osmolality were not statistically different in the nephrectomized vs. control rats at any time and remained constant in each group throughout the experimental period. Central venous pressure (CVP) did not change significantly in both groups 24 h and 6 days following surgery. CVP rose similarly in both groups immediately following saline loading and returned to preload levels 1 h later.(ABSTRACT TRUNCATED AT 250 WORDS)

Polonium metabolism in adult female baboons

The biokinetics of polonium in nonhuman primates (Papio anubis) has been studied after intravenous injection of 210Po citrate. The urinary excretion of polonium in the baboon could be described by a single exponential function with a half-time of 15.6 days. Excretion fractions of polonium were found to be markedly different from those reported for other species, including humans. Polonium-210 was found to be distributed throughout the soft tissues of the baboon with 29% of the injected polonium being deposited in liver, 7% in kidneys and 0.6% in spleen. Retention of polonium in all tissues exhibited single exponential functions; however, the biological half-times were variable, ranging from 15 to 50 days.

Quantitative differences in interleukin-2 and interleukin-4 production by antigen-stimulated splenocytes from individually- and group-housed mice

The effects of differential housing on T-helper (TH) cell activation were investigated. BALB/c and C57Bl/6 male mice housed 1 or 4 per cage were administered three i.p. injections of keyhole limpet hemocyanin (KLH) over several weeks. Effects of differential housing on in vitro antigen-specific interleukin (IL)-2 (a TH1 cell derived cytokine) and IL-4 (a TH2 cell derived cytokine) production were observed. BALB/c mice housed alone produced significantly more IL-4 than BALB/c mice housed in groups. C57Bl/6 mice housed alone produced significantly more IL-2 than C57Bl/6 mice housed in groups. Differential housing did not influence either IL-2 production among BALB/c mice or IL-4 production among C57Bl/6 mice. These data demonstrate that environmental conditions can influence cytokine production by both TH-1 dominant (C57Bl/6) and TH-2 dominant (BALB/c) mice.

CO2 anesthesia facilitates a serum antibody response to orally-administered antigens

Under most experimental circumstances, mice fed a protein antigen produce a smaller serum antibody response than the response elicited in mice that are parenterally immunized with that same antigen. In our experiments, mice fed keyhole limpet hemocyanin or herpes simplex virus type 1 had low, if any, serum IgG antibody responses regardless of whether antigen consumption was voluntary (in drinking fluids) or involuntary (force-fed by pipette). However, when force-feeding occurred during CO2 anesthesia, mice produced significantly higher serum antibody responses, which were comparable to those elicited in mice injected intraperitoneally with the same antigen. Although its mechanism of action is unclear, this potentiating effect does not appear to be mediated by possible CO2-mediated entry of the antigens into the respiratory tract, since mice fed antigen immediately before CO2 anesthesia also had a substantial antibody response.

Relationship between Renal Mass and Atrial Natriuretic Peptide Release

We studied basal serum atrial natriuretic peptide (ANP) levels and the response to acute salt loading in rats with different grades of functional renal mass reduction. The six groups of rats studied included 2 controls, i.e. unoperated (n = 12) and sham-operated (n = 24) groups. Each of the 4 experimental groups (n = 24 in each) underwent one of the following procedures: bilateral nephrectomy; unilateral nephrectomy; bilateral ureteral ligation; unilateral ureteral ligation. Basal ANP was assessed in the intact controls and operated groups 4, 8,16 and 24 h after surgery. In addition, ANP was determined in the sham-operated controls and in the experimental groups 1 h following acute intravenous saline loading performed 4 h after surgery with central venous pressure monitoring. Basal ANP dropped significantly following bilateral nephrectomy but was not significantly altered after unilateral nephrectomy or the two modalities of ureteral ligation . In all 4 experimental groups ANP failed to rise after saline loading. We conclude that substantial renal damage results in early impairment in ANP secretion suggesting the existence of a renal physiological stimulus controlling ANP release by cardiac atria.

Relationship between Renal Mass and Atrial Natriuretic Peptide Release

Serial serum atrial natriuretic peptide (ANP) determinations were performed in 15 uninephrectomized Charles River rats and in 15 sham-operated control animals during the 60 days following surgery. In a second group of 7 control and 7 uninephrectomized animals housed in metabolism cages, serum ANP, body weight, 24-hour urine volume, osmolality and sodium excretion were serially measured. In a third group of uninephrectomized and control rats the effect of acute salt loading 24 h, 6 and 60 days after surgery on serum ANP was studied. No significant changes in ANP levels were observed during the 60 days following surgery in control animals. In the uninephrectomized animals a sharp drop in basal ANP levels was evident 24 and 48 h after surgery, but increased levels of serum ANP were seen from day 6 to 28. Thereafter ANP returned to baseline levels for the rest of the study period. Urinary sodium excretion decreased in the nephrectomized animals on days 1 and 2 following surgery. No such change was seen in the control animals during the same period. Body weight, 24-hour urine volume and urine osmolality were not statistically different in the nephrectomized vs. control rats at any time and remained constant in each group throughout the experimental period. Central venous pressure (CVP) did not change significantly in both groups 24 h and 6 days following surgery. CVP rose similarly in both groups immediately following saline loading and returned to preload levels 1 h later. Nephrectomized animals showed no change in serum ANP 1 h after saline loading performed 24 h after surgery, while in control animals acute saline load resulted, as expected, in a significant rise in serum ANP. 6 and 60 days following surgery, augmented ANP release 1 h after acute salt loading was evident in both the nephrectomized and control groups. We suggest that some as yet unknown mechanism exists through which the renal mass contributes to the control of ANP secretion by the cardiac atria.

Conditioned enhancement of antibody production using antigen as the unconditioned stimulus

Antigen is the most salient stimulus for an unconditional activation of the immune system. BALB/c mice were given repeated immunizations with keyhole limpet hemocyanin (KLH) paired with a gustatory conditioned stimulus (CS). A classically conditioned enhancement of anti-KLH antibody titers was observed when conditioned mice were reexposed to the CS in the context of reexposure to a minimally immunogenic dose of that same antigen. An interaction between signals derived from the neuroendocrine and immune systems is hypothesized to mediate this conditioned immune response.

Renal uric acid handling in non-insulin-dependent diabetic patients with elevated glomerular filtration rates

1. Hypouricaemia is prevalent in diabetic patients. In most of the studies, the diabetic patients had some degree of diabetic nephropathy as evidenced by a decreased glomerular filtration rate and proteinuria. Therefore we studied renal uric acid handling in a group of type II diabetic patients with elevated glomerular filtration rates. 2. Eighteen type II diabetic patients with normal kidney functions and elevated glomerular filtration rate and a group of 18 healthy, age- and weight-matched control subjects, were studied. Serum fructosamine, creatinine and uric acid levels were determined. Twenty-four hour urine collections were obtained, and microalbumin, glucose, creatinine and uric acid, were measured. 3. The creatinine clearance was higher and the serum uric acid concentration was lower in the diabetic patients (P < 0.05). The 24 h urinary uric acid excretion and filtered uric acid load were similar in both groups. However, the derived parameters of uric acid clearance and fractional excretion were significantly higher in the diabetic patients (P < 0.002 and P < 0.05, respectively). A negative correlation was apparent between serum fructosamine concentration and serum uric acid concentration (r = -0.76). A positive correlation was found between serum fructosamine concentration and fractional uric acid excretion (r = 0.64) and between serum fructosamine concentration and filtered uric acid load (r = 0.66). A positive correlation was found between creatinine clearance and 24 h uric acid excretion (r = 0.61) and between creatinine clearance and filtered uric acid load (r = 0.82).(ABSTRACT TRUNCATED AT 250 WORDS)

[Aorto-bifemoral graft infection presenting as fever of unknown origin]

Aorto-femoral graft infection is a rare complication and presents with a variety of signs and symptoms. Fever of unknown origin as a manifestation of graft infection has been described in only a few cases. We present a 65-year-old man with infection of an aorto-bifemoral graft.

Type II diabetes mellitus, congestive heart failure, and zinc metabolism

Zinc status was assessed in patients with type II diabetes mellitus and congestive heart failure (CHF). Three groups of patients were enrolled into the study: Group 1: 15 patients with type II diabetes mellitus and CHF; Group 2: 20 patients with isolated type II diabetes mellitus; and Group 3: nine patients with isolated CHF. Twenty-four-hour urine was measured for creatinine, protein, and zinc, and blood was drawn for creatinine, proteins, liver enzymes, hemoglobin A1c, and zinc. Insulin treatment and hemoglobin A1c were comparable in the diabetic patients of groups 1 and 2, but group 1 was also treated with captopril and diuretics like the CHF patients of group 3. Plasma zinc levels were statistically similar in all three groups, but urinary zinc excretion (mumol/24 h) and urinary zinc: creatinine (mumol/mmol) ratio were significantly higher in the type II diabetics and CHF group (27.2 +/- 1.5; 1.69 +/- 0.6, respectively) compared to the diabetic patients alone (19.4 +/- 0.76; 0.97 +/- 0.3, respectively) and the CHF patients (9.7 +/- 0.3; 0.62 +/- 0.3, respectively). and the CHF patients (9.7 +/- 0.3; 0.62 +/- 0.3, respectively). Patients with type II diabetes mellitus and CHF were treated with higher doses of captopril than the CHF patients (56.25 +/- 24 mg vs 18.8 +/- 11 mg P < 0.05). Thus, patients with type II diabetes mellitus and CHF excrete larger amounts of zinc, which may eventually lead to zinc deficiency.