Exchangeable and Total Body Potassium in Patients with Chronic Renal Failure

Total body potassium determined by whole-body monitoring and exchangeable body potassium estimated with ⁴³K were measured simultaneously in 12 patients with stable chronic renal failure. Values for the exchangeable potassium were obtained after equilibration periods of 24, 48, and 64 hours. The exchangeable body potassium, expressed as a percentage of the total body potassium (mean ± S.E. of mean), gave values of 60·7 ± 3·3%, 83·6 ± 2·7%, and 85·9 ± 2·7% at 24, 48, and 64 hours respectively. It seems that the equilibration between radioactive and native potassium is incomplete after 24 hours; and that exchangeable potassium measured at this time is not an accurate index of the status of total body potassium in such patients. Furthermore, the finding that the value at 64 hours is significantly less than found in healthy subjects suggests that the exchangeable potassium is a smaller fraction of the total body potassium in patients with chronic renal failure.     

Impaired renal functional reserve and albuminuria in essential hypertension

The stimulatory effects of an infusion of amino acids on glomerular filtration rate has previously been used to measure renal functional reserve and detect glomerular hyperfiltration. Thirty four patients with mild to moderate essential hypertension and seemingly normal renal function and 22 healthy controls were given infusions of amino acids to investigate whether renal functional reserve is reduced in essential hypertension and to detect patients at risk of renal damage. Although basal creatinine clearance increased after the infusion of amino acids in the controls (mean 27·9 ml/min; 95% confidence interval 18·2 to 37·6), the overall change was lower in the patients (mean 13·4 ml/min; 8·3 to 18·5), 11 of the 34 showing no increase at all. In these 11 non-responders the mean systolic blood pressure was higher than that in the 23 others (178·5 mm Hg v 157 mm Hg, respectively). Mean urinary albumin excretion was abnormal in the patients (93·3 mg/24 h; 44·2 to 142·4); eight of the 11 non-responders had an albumin excretion above the normal range (>20 mg/24 h). In the 11 patients without renal functional reserve a positive correlation was found between basal creatinine clearance and albumin excretion (r=0·695).As consumed renal reserve and albuminuria are markers of glomerular hyperfiltration studying renal function before and after infusion of amino acids can detect hypertensive patients at risk of progressive renal damage.     

Surgical Treatment of Severe Attacks of Ulcerative Colitis,with Special Reference to the Advantages of Early Operation

The management and outcome of 258 severe attacks of ulcerative colitis from 1952 to 1969 has been reviewed. If remission did not occur during an initial course of intensive medical treatment, including administration of corticosteroids, operation (generally ileostomy with proctocolectomy or subtotal colectomy) was performed. This took place some 12 to 17 days after admission as a rule during the years 1952-63, but usually within five to seven days from 1964 to 1969.Roughly half the attacks underwent spontaneous remission during the two periods, but the medical mortality was 4·8% in the former and 0·7% in the latter, the operative mortality 20·0 and 7·0%, and the overall mortality 11·3 and 4.5% respectively. The lowering of the mortality was particularly striking in severe first attacks and in severe attacks in patients over 60 years of age.Perforation of the colon was found in 21 cases, or nearly 20% of 112 patients coming to operation during attacks, being commoner in the first period (32·5%) than in the second (11·1%). The immediate mortality of all such operations was 11·6%; in cases with perforation it was 28·6%.Acute colonic dilatation was observed in 28 cases. All but one were treated by emergency colectomy, at which the colon was noted to be perforated in 11. The mortality of these operations was 18·5%.Follow-up of the 140 patients who survived without coming to operation during their attacks shows that 52 (37·1%) subsequently underwent surgical treatment either during further attacks or electively.Though all 258 attacks were thought at the time to be due to ordinary ulcerative colitis, subsequent pathological examination of operative specimens derived from 98 patients who came to urgent or subsequent operation during the 1964-9 period revealed that the lesion in the large bowel was Crohn''s disease in 17 instances.     

High Dosage Metolazone in Chronic Renal Failure

Metolazone is a modified quinazolinesulphonamide and in a dose of between 4 and 7·5 mg is an effective diuretic in man with normal renal function. Fourteen patients with non-oedematous stable chronic renal failure (creatinine clearance ranging from 1·2 to 12 ml/min) were given metolazone in doses ranging from 20-150 mg. A noticeable increase in urine flow and sodium excretion occurred, free water clearance increased, and there was a small but significant increase in potassium excretion. No side effects were noted.     

Incomplete Restoration of Angiotensin II - Induced Renal Extracellular Matrix Deposition and Inflammation Despite Complete Functional Recovery in Rats

Some diseases associated with a temporary deterioration in kidney function and/or development of proteinuria show an apparently complete functional remission once the initiating trigger is removed. While it was earlier thought that a transient impairment of kidney function is harmless, accumulating evidence now suggests that these patients are more prone to developing renal failure later in life. We therefore sought to investigate to what extent renal functional changes, inflammation and collagen deposition are reversible after cessation of disease induction, potentially explaining residual sensitivity to damage. Using a rat model of Angiotensin II (Ang II)-induced hypertensive renal disease we show the development of severe hypertension (212 ± 10.43 vs. 146 ± 1.4 mmHg, p<0.001) and proteinuria (51.4 ± 6.3 vs. 14.7 ± 2.0 mg/24h, p<0.01) with declined creatinine clearance (2.0 ± 0.5 vs. 4.9 ± 0.6 mL/min, p<0.001) to occur after 3 weeks of Ang II infusion. At the structural level, Ang II infusion resulted in interstitial inflammation (18.8 ± 4.8 vs. 3.6 ± 0.5 number of macrophages, p<0.001), renal interstitial collagen deposition and lymphangiogenesis (4.1 ± 0.4 vs. 2.2 ± 0.4 number of lymph vessels, p<0.01). Eight weeks after cessation of Ang II, all clinical parameters, pre-fibrotic changes such as myofibroblast transformation and increase in lymph vessel number (lymphangiogenesis) returned to control values. However, glomerular desmin expression, glomerular and periglomerular macrophages and interstitial collagens remained elevated. These dormant abnormalities indicate that after transient renal function decline, inflammation and collagen deposition may persist despite normalization of the initiating pathophysiological stimulus perhaps rendering the kidney more vulnerable to further damage.     

AltitudeOmics: Rapid Hemoglobin Mass Alterations with Early Acclimatization to and De-Acclimatization from 5260 m in Healthy Humans

It is classically thought that increases in hemoglobin mass (Hbmass) take several weeks to develop upon ascent to high altitude and are lost gradually following descent. However, the early time course of these erythropoietic adaptations has not been thoroughly investigated and data are lacking at elevations greater than 5000 m, where the hypoxic stimulus is dramatically increased. As part of the AltitudeOmics project, we examined Hbmass in healthy men and women at sea level (SL) and 5260 m following 1, 7, and 16 days of high altitude exposure (ALT1/ALT7/ALT16). Subjects were also studied upon return to 5260 m following descent to 1525 m for either 7 or 21 days. Compared to SL, absolute Hbmass was not different at ALT1 but increased by 3.7±5.8% (mean ± SD; n = 20; p<0.01) at ALT7 and 7.6±6.6% (n = 21; p<0.001) at ALT16. Following descent to 1525 m, Hbmass was reduced compared to ALT16 (−6.0±3.7%; n = 20; p = 0.001) and not different compared to SL, with no difference in the loss in Hbmass between groups that descended for 7 (−6.3±3.0%; n = 13) versus 21 days (−5.7±5.0; n = 7). The loss in Hbmass following 7 days at 1525 m was correlated with an increase in serum ferritin (r = −0.64; n = 13; p<0.05), suggesting increased red blood cell destruction. Our novel findings demonstrate that Hbmass increases within 7 days of ascent to 5260 m but that the altitude-induced Hbmass adaptation is lost within 7 days of descent to 1525 m. The rapid time course of these adaptations contrasts with the classical dogma, suggesting the need to further examine mechanisms responsible for Hbmass adaptations in response to severe hypoxia.     

Assessment of Upper Airways Obstruction

An indication of obstruction to the upper airways (trachea and larynx) may be obtained by calculating the ratio of the forced expired volume in one second to the peak expiratory flow rate (FEV₁/PEFR). This index was found to be usually less than 10 in normal subjects (mean 7·3), and in patients with asthma (mean 6·9), chronic bronchitis (mean 7·7), or interstitial lung disease (mean 6·3). A study of simulated upper airways obstruction showed that this index rises as the obstruction becomes more severe. All of 18 patients with proved upper airways obstruction had FEV₁/PEFR indices greater than 10 (mean 14·0). This test can be carried out with forced expiratory manoeuvres only, and it does not require the use of complicated equipment. An FEV₁/PEFR ratio greater than 10, when upper airways obstruction is suspected, indicates that significant obstruction may be present. High values suggest that the obstruction may be severe, and that further investigations are indicated.     

Long-Term Treatment of Clonidine,Atenolol, Amlodipine and Dihydrochlorothiazide,but Not Enalapril,Impairs the Sexual Function in Male Spontaneously Hypertensive Rats

This study was designed to investigate the impact of representative antihypertensive drugs of 5 classes on the sexual function in male spontaneously hypertensive rats (SHR) at doses that achieved similar blood pressure (BP) reduction. The experiment was performed in 6 groups of male SHR. The dose are 20 μg/kg/day for clonidine, 3 mg/kg/day for enalapril, 20 mg/kg/day for atenolol, 2 mg/kg/day for amlodipine, and 10 mg/kg/day for dihydrochlorothiazide. SHR were treated for 3 months, and then the penile erection and sexual behavior were detected. After BP recording, SHR were killed to evaluate the organ-damage, weight of accessory sex organs and levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone in serum. Five drugs had the similar efficacy on BP reduction. All drugs except of enalapril, significantly prolonged the mount latency, and decreased the mount frequency (P<0.05). Clonidine also reduced the conception rate (45% vs. 80% in control group, P<0.05). Amlodipine and dihydrochlorothiazide significantly increased the testosterone level (0.79±0.30, 0.80±0.34 vs. 0.49±0.20 in control group, unit: ng/dl, P<0.05). Enalapril, atenolol and amlodipine also significantly decreased the BP variability (systolic, 8.2±2.5, 7.6±1.8, 8.9±2.0 vs. 12.2±3.8 in control group, unit: mm Hg). All these drugs significantly decreased the organ-damage (P<0.05). In conclusion, long-term treatment with 5 common antihypertensive drugs possessed obvious organ protection in SHR. Clonidine, atenolol, amlodipine and dihydrochlorothiazide, but not enalapril, impair sexual function.     

Serum and Urinary Folate in Liver Disease

During the active phase of viral hepatitis urinary folate loss was found to be 8·0 to 48·3 (mean 31·1) μg./day, compared with a normal urinary folate excretion of 0·1 to 18·0 (mean 9·5) μg./day. In cirrhosis and cardiac failure with congestive hepatomegaly the corresponding values were 25·8 to 55·0 (mean 35·7) μg./day and 2·5 to 61·6 (mean 26·9) μg./day, respectively. Urinary folate loss may be a significant factor in the aetiology of folate deficiency of chronic liver disease, particularly when dietary intake is poor.After prolonged dialysis in Visking casing urinary folate was almost totally dialysable, but an appreciable fraction of serum folate was not, even after 72 hours. The dialysable (free) folate fraction of serum and urine disappeared maximally during the first six hours'' dialysis, and was virtually cleared after 24 hours'' dialysis; clearance curves in normal individuals and in liver disease were comparable. The non-dialysable serum folate fraction was of similar magnitude in all subjects studied, in spite of marked variation in total folate, and probably represented protein-bound folate.     

Hemodynamic and therapeutic effects of intravenous dopamine

The effects of intravenous dopamine were evaluated in 10 patients with severe but stable coronary artery disease, 17 consecutive patients with primary cardiogenic shock and 3 with severe congestive heart failure and oliguria. Dopamine infusion at 10 μg/kg·min in the 10 patients increased cardiac output by 35%, left ventricular peak dP/dt by 38%, left ventricular minute work index by 44% and mean systolic ejection rate by 7% (P < 0.01); heart rate, aortic pressure, left ventricular end-diastolic pressure and tension-time index were unchanged. For oxygen, potassium and lactate, arterial and coronary sinus values, coronary arteriovenous oxygen differences and myocardial extraction were unchanged. Hemodynamically 13 of the 17 patients in shock responded favourably to dopamine infusion (0.5 to 15 μg/kg·min), with decrease in heart rate, increase in systolic arterial pressure from 75 to 100 mm Hg (P <0.001), decrease in ventricular filling pressure from 20 to 16 mm Hg (P < 0.01) and increase in urine output from 10 to 100 ml/h (P < 0.01). Eleven of those patients survived the shock episode. A close relation was observed between the hemodynamic response to dopamine, survival from the shock episode and the time between onset of shock and initiation of therapy. Low rates of dopamine infusion induced diuresis in the three patients with severe cardiac failure.Dopamine thus seems to improve the mechanical efficiency of the heart in coronary artery disease. Cardiac output is selectively increased and myocardial ischemia does not appear to be induced; those beneficial effects as well as presumably specific action on renal flow and natriuresis, improve immediate survival from cardiogenic shock and severe heart failure.     

Culture-Modified Bone Marrow Cells Attenuate Cardiac and Renal Injury in a Chronic Kidney Disease Rat Model via a Novel Antifibrotic Mechanism

Background

Most forms of chronic kidney disease are characterized by progressive renal and cardiac fibrosis leading to dysfunction. Preliminary evidence suggests that various bone marrow-derived cell populations have antifibrotic effects. In exploring the therapeutic potential of bone marrow derived cells in chronic cardio-renal disease, we examined the anti-fibrotic effects of bone marrow-derived culture modified cells (CMCs) and stromal cells (SCs).

Methodology/Principal Findings

In vitro, CMC-conditioned medium, but not SC-conditioned medium, inhibited fibroblast collagen production and cell signalling in response to transforming growth factor-ß. The antifibrotic effects of CMCs and SCs were then evaluated in the 5/6 nephrectomy model of chronic cardio-renal disease. While intravascular infusion of 10⁶ SCs had no effect, 10⁶ CMCs reduced renal fibrosis compared to saline in the glomeruli (glomerulosclerosis index: 0.8±0.1 v 1.9±0.2 arbitrary units) and the tubulointersitium (% area type IV collagen: 1.2±0.3 v 8.4±2.0, p<0.05 for both). Similarly, 10⁶ CMCs reduced cardiac fibrosis compared to saline (% area stained with picrosirius red: 3.2±0.3 v 5.1±0.4, p<0.05), whereas 10⁶ SCs had no effect. Structural changes induced by CMC therapy were accompanied by improved function, as reflected by reductions in plasma creatinine (58±3 v 81±11 µmol/L), urinary protein excretion (9×/÷1 v 64×/÷1 mg/day), and diastolic cardiac stiffness (left ventricular end-diastolic pressure-volume relationship: 0.030±0.003 v 0.058±0.011 mm Hg/µL, p<0.05 for all). Despite substantial improvements in structure and function, only rare CMCs were present in the kidney and heart, whereas abundant CMCs were detected in the liver and spleen.

Conclusions/Significance

Together, these findings provide the first evidence suggesting that CMCs, but not SCs, exert a protective action in cardio-renal disease and that these effects may be mediated by the secretion of diffusible anti-fibrotic factor(s).     

The Effect of Neutral Peritoneal Dialysis Solution with Low Glucose-Degradation-Product on the Fluid Status and Body Composition – A Randomized Control Trial

Background

Previous studies report conflicting results on the benefit of peritoneal dialysis (PD) patients treated with low glucose degradation product (GDP) solution. The effects of low GDP solution on body fluid status and arterial pulse wave velocity (PWV) have not been studied.

Methods

We randomly assigned 68 incident PD patients to low GDP (Intervention Group) or conventional solutions (Control Group); 4 dropped off before they received the assigned treatment. Patients were followed for 52 weeks for changes in ultrafiltration, residual renal function, body fluid status and arterial PWV.

Result

After 52 weeks, Intervention Group had higher overhydration (3.1 ± 2.6 vs 1.9 ± 2.2 L, p = 0.045) and extracellular water volume (17.7 ± 3.9 vs 15.8 ± 3.1 L, p = 0.034) than Control Group. There was no significant difference in PWV between groups. There was no significant difference in residual renal function between the Groups. Intervention Group had lower ultrafiltration volume than Control Group at 4 weeks (0.45 ± .0.61 vs 0.90 ± 0.79 L/day, p = 0.013), but the difference became insignificant at later time points. Intervention Group had lower serum CRP levels than Control Group (4.17 ± 0.77 vs 4.91 ± 0.95 mg/dL, p < 0.0001).

Conclusion

Incident PD patients treated with low GDP solution have less severe systemic inflammation but trends of less ultrafiltration, and more fluid accumulation. However, the effects on ultrafiltration and fluid accumulation disappear with time. The long term effect of low GDP solution requires further study.

Trial Registration

ClinicalTrials.gov NCT00966615     

Blood Angiotensin II Levels of Normal and Hypertensive Subjects

A specific radioimmunoassay for angiotensin II has shown that its normal concentration in arterial blood is 2·4±1·2 (S.D.) mμg./l00 ml.; the venous level is consistently below this value, being usually 50–75% of it. Definite rises in blood angiotensin II levels were found in some patients with hypertension, both essential and secondary to renal disease. Extremely low levels were observed in two anephric women, and in one patient with Conn''s syndrome. This radioimmunoassay offers a valuable alternative to renin bioassay in evaluation of the role of the renal pressor system in clinical disorders associated with hypertension and aldosteronism.     

Impaired aerobic work capacity in insulin dependent diabetics with increased urinary albumin excretion

To assess whether decreased aerobic work capacity was associated with albuminuria in insulin dependent diabetics aerobic capacity was measured in three groups of 10 patients matched for age, sex, duration of diabetes, and degree of physical activity. Group 1 comprised 10 patients with normal urinary albumin excretion (<30 mg/24 h), group 2 comprised 10 with incipient diabetic nephropathy (urinary albumin excretion 30-300 mg/24 h, and group 3 comprised 10 with clinical diabetic nephropathy (urinary albumin excretion >300 mg/24 h). Ten non-diabetic subjects matched for sex, age, and physical activity served as controls. Oxygen uptake was similar in the four groups at rest and during a 75 W workload. Maximal oxygen uptake was also similar in the control subjects and group 1 (median 41·7, (range 29·1-53·0) ml/kg/min v 38·5 (26·6-59·2) ml/kg/min, respectively), but was significantly lower in group 2 (27·7 (13·9-44·3) ml/kg/min) and group 3 (26·8 (22·6-36·7) ml/kg/min). The difference in maximal oxygen uptake between groups 1 and 2 was 10·8 ml/kg/min (95% confidence interval 3·6 to 23·4 ml/kg/min) and between groups 1 and 3, 11·7 ml/kg/min (4·9 to 22·5 ml/kg/min). These differences were not explained by differences in metabolic control or the degree of autonomic neuropathy.Thus the insulin dependent diabetics with only slightly increased urinary albumin excretion had an appreciably impaired aerobic work capacity which could not be explained by autonomic neuropathy or the duration of diabetes. Whether the reduced capacity is due to widespread microangiopathy or another pathological process affecting the myocardium remains to be established.     

Serum Lipids in Cholelithiasis: Effect of Chenodeoxycholic Acid Therapy

Hypercholesterolaemia has been predicted as a possible complication of chenodeoxycholic acid treatment for gall stones. To exclude this, fasting serum lipids were measured in patients with stones before and at monthly intervals for six months after starting chenodeoxycholic acid. Before treatment half of a group of 36 patients with presumed cholesterol gall stones had serum cholesterol levels exceeding 260 mg/100 ml or serum triglyceride values greater than 160 mg/100 ml or both; these lipid levels were significantly greater than those in control subjects matched for age and sex. Treatment with chenodeoxycholic acid (0·5-1·5 g/day by mouth) did not change serum cholesterol levels but did significantly reduce serum triglyceride concentrations from a pretreatment level of 118 (± S.E. of mean 11·7) mg/100 ml to 95 (± 7·2) mg/100 ml after six months of therapy. The mechanism of this triglyceride-lowering action of chenodeoxycholic acid is not known, but it may have therapeutic value in patients with hypertriglyceridaemia.     

Losartan reduces oxidative damage to renal DNA and conserves plasma antioxidant capacity in diabetic rats

Increased reactive oxygen species (ROS) levels produced by hyperglycemia and angiotensin-II (AT-II) are considered among the pathogenic factors in the malignant transformation of diabetic renal cells. We aimed to investigate the potential role of AT-II in the increased cancer risk seen in diabetes; measuring oxidative damage to renal DNA and protective antioxidant defenses, including adiponectin (Adp) and plasma antioxidant capacity by the Ferric Reducing Ability of Plasma (FRAP) method. In the kidney of streptozotocin (STZ)-induced (55 mg/kg) diabetic rats either treated or not treated for 3 weeks with losartan, an AT-II type 1 receptor antagonist (20 mg/kg/day); we measured 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodGuo) levels, as an index of oxidative DNA damage, circulating Adp and FRAP. Diabetic rats showed significantly higher 8-oxodGuo levels in renal DNA (8.48 ± 0.98 × 10⁻⁶ dG, mean ± SEM n = 11) than normoglycemic ones (1.18 ± 0.04 × 10⁻⁶ dG, mean ± SEM, n=7) and lower plasma Adp and FRAP levels in comparison to normoglycemics. The treatment of diabetic rats with losartan significantly (P < 0.01) reduced 8-oxodGuo levels (5.4 ± 0.58 × 10⁻⁶ dG, mean ± SEM n=9) in renal DNA and conserved FRAP values. Moreover, an inverse correlation was found between 8-oxodGuo in kidney DNA and circulating Adp levels in normoglycemic and diabetic rats. Losartan treatment preserves FRAP levels, reduces DNA oxidative injury and thus the carcinogenesis risk. Furthermore, our results indicate that Adp plasma levels are a further marker of oxidative injury to the kidney and confirm that it is an important part of the plasma antioxidant defense.     

THE SULFONIUM SALT OF MUSTARD GAS: BIS-β-[BIS(β-HYDROXYETHYL) SULFONIUM] ETHYLSULFIDE DICHLORIDE (H·2TDG)

1. The sulfonium salt H·2TDG is formed when H is mixed with even dilute solutions of TDG. Crystalline H·2TDG was isolated from such a reaction mixture. A simple method of preparation of this salt is outlined. 2. A material which differs from H·2TDG in that it hydrolyzes faster, is formed when H hydrolyzes in water. This material is probably H·1TDG but it was not isolated. Approximately 5 to 8 per cent of the original H is converted to this sulfonium salt. 3. The hydrolysis constant of M/100 H·2TDG has been determined at 20°, 25.5°, 37°, 75°, and 100°C., a temperature coefficient, Q ₁₀, of 3–4 was obtained. The effect of temperature is in agreement with that predicted by the Arrhenius equation. An activation energy of 26,000 calories was calculated.     

Intranasal Treatment with Poly(I·C) Protects Aged Mice from Lethal Respiratory Virus Infections

In the 2002-2003 severe acute respiratory syndrome coronavirus (SARS-CoV) epidemic, no patients under 24 years of age died, while mortality was greater than 50% in those over 65 years. Greater than 90% of all deaths from influenza A virus (IAV) occur in the elderly (>65 years of age). To address this age-related susceptibility to SARS-CoV and IAV, we infected C57BL/6 (B6) mice with mouse-adapted SARS-CoV (MA15) or IAV (PR8), both of which cause severe disease in aged mice. Intranasal pretreatment of aged mice with poly(I·C) (a TLR3 agonist) and, to a lesser extent, CpG, R848, or lipopolysaccharide (TLR9, TLR7/8, or TLR4 agonists), provided a high level of protection [90% to 100% survival rate after poly(I·C) treatment] against lethal MA15 or IAV challenge and reduced pathological changes and virus loads in the lungs at early times after infection. Poly(I·C) pretreatment upregulated beta interferon (IFN-β), IFN-γ, IL-1β, and tumor necrosis factor (TNF) gene expression in the lungs. Intranasal pretreatment with IFN-β or IFN-γ but not IL-1β or TNF also protected aged mice, consistent with the notion that poly(I·C) pretreatment functioned, at least in part, by inducing IFN-β and IFN-γ. We also identified a potential cellular target for poly(I·C) by showing that treatment inhibited virus replication in primary human airway epithelial cells. These results suggest that intranasal poly(I·C) should be evaluated as a prophylactic agent in aged individuals at high risk for contracting SARS-CoV or IAV infections.     

Relaxin Does Not Improve Angiotensin II-Induced Target-Organ Damage

Relaxin is a corpus-luteum produced protein hormone with vasodilatatory, anti-fibrotic, and angiogenic properties that are opposite to angiotensin (Ang) II. We investigated whether or not relaxin ameliorates Ang II-induced target-organ damage. We used double transgenic rats harboring both human renin and angiotensinogen genes (dTGR) that develop severe hypertension, target-organ damage, and die untreated within 7–8 weeks. Recombinant relaxin at a low (26 μg/kg/d) and a high dose (240 μg/kg/d) was given to 4 week-old dTGR and age-matched Sprague-Dawley rats (SD). Systolic blood pressure increased progressively in untreated dTGRs from 162±3 mmHg at week 5 to 225±5 mmHg at week 7. Relaxin had no effect on blood pressure whereas SD rats were normotensive (106±1 mmHg). Untreated and relaxin-treated dTGR had similarly severe cardiac hypertrophy indices. Relaxin did not ameliorate albuminuria and did not prevent matrix-protein deposition in the heart and kidney in dTGR. Finally, relaxin treatment did not reduce mortality. These data suggest that pharmacological doses of relaxin do not reverse severe effects of Ang II.     

Use of 4% Chlorhexidine Detergent Solution (Hibiscrub) and Other Methods of Skin Disinfection

In a comparison of three antiseptic detergent preparations for hand washing, Hibiscrub, a 4% chlorhexidine detergent solution, caused a significantly greater estimated immediate reduction of skin flora (86·7% ± 3·0) than was obtained with Dermofax, a 0·75% chlorhexidine detergent solution (55·5% ± 5·1), or with Disadine scrub, a povidone iodine detergent preparation (68% ± 6·8). After six applications the mean estimated reductions of skin flora were 99·2% ± 0·2 for Hibiscrub, 97·7% ± 0·7 for povidone iodine, and 91·8% ± 1·6 for Dermofax.After a series of hand washings with Hibiscrub, as with a hexachlorophane detergent preparation, a further large reduction of skin flora, shown by bacterial counts of hand sampling, was obtained by a second phase of disinfection consisting of two minutes'' application on gauze swabs of 0·5% chlorhexidine digluconate in 70% ethanol; a further wash with Hibiscrub, in place of alcoholic chlorhexidine, for the second phase of disinfection caused an increase rather than a reduction in the yield of bacteria on skin sampling. Unlike this “two-phase” disinfection, the application for 30 minutes of compresses soaked in 10% aqueous povidone iodine or in 0·5% aqueous chlorhexidine digluconate did not cause a greater reduction in skin flora than that obtained by the conventional two minutes'' application on gauze of 0·5% chlorhexidine in 70% ethanol.Chlorocresol (0·3%) liquid soap (the base used for Ster-Zac liquid hexachlorophane soap) caused a mean reduction of skin flora when used for hand washing of 29% after one application and 72% after six applications spread over two days. This formulation, though less active and more variable as a detergent skin antiseptic than chlorhexidine, hexachlorophane, or povidone iodine detergent preparations, is an inexpensive disinfectant soap which could be useful in catering establishments. Alcoholic cetrimide applied as for disinfection of an operation site caused a reduction of skin flora greater than that shown by aqueous cetrimide but comparable to that shown by 70% ethyl alcohol in previous experiments.