In vivo antifungal effect of Combretum and Terminalia species extracts on cutaneous wound healing in immunosuppressed rats.

Acetone leaf extracts of Combretaceae species Combretum imberbe Wawra, Combretum nelsonii Duemmer, Combretum albopunctatum Suesseng, and Terminalia sericea Burch ex DC and a mixture of asiatic acid and arjunolic acid isolated from C. nelsonii were tested for antifungal activity against Candida albicans, Cryptococcus neoformans, Microsporum canis, and Sporothrix schenckii on wounds of immunocompromised Wistar rats. The therapeutic agents were selected based on low MIC values ranging 0.02-2.5 mg/mL and low toxicity (LC50) ranging 75.7-168.6 microg/mL. Seven circular, full-thickness wounds were made on the back skin of 24 Wistar rats, under general anesthetic and using an aseptic technique. Rats were infected with different fungal pathogens in groups of six. The treatments were administered topically using 20% concentrations of each extract in aqueous cream. Amphotericin B was used as positive control. Erythema, exudate, crust formation, swelling, and ulceration were used to determine the wound healing process. Throughout the experiment, body temperature, measured using a subcutaneous probe, and weight of the rats were found to be within normal ranges. Epithelial closure in all rats occurred by 17 days. There was no significant difference in contraction of the lesion areas treated with different extracts. The variability in erythema at each lesion in rats infected with different fungal pathogens differed with treatments; the lesion without treatment took a longer time to heal in all cases. Exudate formation was observed until day 12 in rats infected with C. albicans and day 8 in rats infected with C. neoformans. In lesions infected with M. canis and S. schenckii, exudate formation was observed until day 10. The treated group presented a rigid, dark, and thick crust formation after day 3 until day 15. During histopathological evaluations, scant fungi were noted in all the wounds, indicating that infection had occurred but had generally cleared. The antifungal potential of crude extracts of selected plants and a mixture of asiatic acid and arjunolic acid on the wounds of immunocompromised rats was confirmed. The extracts of these plants may possibly be further developed into drugs for topical treatment of fungally infected wounds.

Glucose-induced changes in Na+/H+ antiport activity and gene expression in cultured vascular smooth muscle cells. Role of protein kinase C.

Increased Na+/H+ antiport activity has been implicated in the pathogenesis of hypertension and vascular disease in diabetes mellitus. The independent effect of elevated extracellular glucose concentrations on Na+/H+ antiport activity in cultured rat vascular smooth muscle cells (VSMC) was thus examined. Amiloride-sensitive 22Na+ uptake by VSMC significantly increased twofold after 3 and 24 h of exposure to high glucose medium (20 mM) vs. control medium (5 mM). Direct glucose-induced Na+/H+ antiport activation was confirmed by measuring Na(+)-dependent intracellular pH recovery from intracellular acidosis. High glucose significantly increased protein kinase C (PKC) activity in VSMC and inhibition of PKC activation with H-7, staurosporine, or prior PKC downregulation prevented glucose-induced increases in Na+/H+ antiport activity in VSMC. Northern analysis of VSMC poly A+ RNA revealed that high glucose induced a threefold increase in Na+/H+ antiport (NHE-1) mRNA at 24 h. Inhibiting this increase in NHE-1 mRNA with actinomycin D prevented the sustained glucose-induced increase in Na+/H+ antiport activity. In conclusion, elevated glucose concentrations significantly influence vascular Na+/H+ antiport activity via glucose-induced PKC dependent mechanisms, thereby providing a biochemical basis for increased Na+/H+ antiport activity in the vascular tissues of patients with hypertension and diabetes mellitus.

Unifying hypothesis of sodium and water regulation in health and disease.

Sodium and water retention is characteristic of edematous disorders including cardiac failure, cirrhosis, nephrotic syndrome, and pregnancy. Nonosmotic vasopressin release has been implicated in the water retention of these edematous disorders. The nonosmotic release of vasopressin is consistently associated with activation of the sympathetic nervous and renin-angiotensin-aldosterone systems in both experimental animals and in edematous patients. Moreover, the sympathetic nervous system has been shown to be involved in the nonosmotic release of vasopressin and activation of the renin-angiotensin system. These findings have led to our proposal that body fluid volume regulation involves the dynamic interaction between cardiac output and peripheral arterial resistance. Neither total extracellular fluid volume nor blood volume is a determinant of renal sodium and water excretion. Rather, renal sodium and water retention is initiated by a decrease in effective arterial blood volume (EABV) due to either a fall in cardiac output or peripheral arterial vasodilation. The acute response to a decrease in EABV involves vasoconstriction mediated by angiotensin, sympathetic mediators, and vasopressin. The slower response to restoring EABV involves vasopressin-mediated water retention and aldosterone-mediated sodium retention. The resultant renal vasoconstriction limits the distal tubular delivery of sodium and water, thus maximizing the water-retaining effect of vasopressin and impairing the normal escape from the sodium-retaining effects of aldosterone. The elevated glomerular filtration rate and filtered sodium load in pregnancy allows increased distal sodium and water delivery in spite of a decrease in EABV, thus limiting edema formation during gestation.

Investigation into the reasons for preventable drug related admissions to a medical admissions unit: observational study.

OBJECTIVE: To describe the drugs and types of medicine management problems most frequently associated with preventable drug related admissions to an acute medical admissions unit. DESIGN: Observation study. SETTING: Medical admissions unit in a teaching hospital in Nottingham, UK. PARTICIPANTS: 4093 patients seen by pharmacists on the medical admissions unit between 1 January and 30 June 2001. MAIN OUTCOME MEASURES: Proportion of admissions that were drug related and preventable, classification of the underlying causes of preventable drug related admissions, and identification of drugs most commonly associated with preventable drug related admissions. RESULTS: Of the admissions seen by pharmacists, 265 (6.5%) were judged to be drug related and 178 (67%) of these were judged to be preventable. Preventable admissions were mainly due to problems with prescribing (63 cases (35%)), monitoring (46 cases (26%)), and adherence to medication (53 cases (30%)). The drugs most commonly implicated were NSAIDs, antiplatelets, antiepileptics, hypoglycaemics, diuretics, inhaled corticosteroids, cardiac glycosides, and beta-blockers. CONCLUSIONS: Potentially preventable drug related morbidity was associated with 4.3% of admissions to a medical admissions unit. In 91% of cases these admissions were related to problems with either prescribing, monitoring, or adherence.

Interrogation of short tandem repeats using fluorescent probes and melting curve analysis: a step towards rapid DNA identity screening.

Current forensic DNA profiling methods rely on the analysis of samples at specialised laboratories with an average turnaround time of several days. The ability to rapidly determine a partial profile of short tandem repeats at the point-of-arrest would be of great benefit to police forces around the world, for example enabling a suspect to be rapidly included or excluded from an investigation. We have developed a homogeneous PCR method for the interrogation of STR loci utilising fluorescent oligonucleotide probes and melting curve analysis. Alleles of the D18S51, TH01 and D8S1179 loci were differentiated and identified on the basis of target length and probe melting temperature. Assay performance was evaluated by comparing melting peak data with the AmpFlSTR SGM Plus system. The method is compatible with direct analysis of unpurified buccal swab samples, enabling a partial STR profile to be generated within 1h.

Which drugs cause preventable admissions to hospital? A systematic review.

AIMS: Previous systematic reviews have found that drug-related morbidity accounts for 4.3% of preventable hospital admissions. None, however, has identified the drugs most commonly responsible for preventable hospital admissions. The aims of this study were to estimate the percentage of preventable drug-related hospital admissions, the most common drug causes of preventable hospital admissions and the most common underlying causes of preventable drug-related admissions. METHODS: Bibliographic databases and reference lists from eligible articles and study authors were the sources for data. Seventeen prospective observational studies reporting the proportion of preventable drug-related hospital admissions, causative drugs and/or the underlying causes of hospital admissions were selected. Included studies used multiple reviewers and/or explicit criteria to assess causality and preventability of hospital admissions. Two investigators abstracted data from all included studies using a purpose-made data extraction form. RESULTS: From 13 papers the median percentage of preventable drug-related admissions to hospital was 3.7% (range 1.4-15.4). From nine papers the majority (51%) of preventable drug-related admissions involved either antiplatelets (16%), diuretics (16%), nonsteroidal anti-inflammatory drugs (11%) or anticoagulants (8%). From five studies the median proportion of preventable drug-related admissions associated with prescribing problems was 30.6% (range 11.1-41.8), with adherence problems 33.3% (range 20.9-41.7) and with monitoring problems 22.2% (range 0-31.3). CONCLUSIONS: Four groups of drugs account for more than 50% of the drug groups associated with preventable drug-related hospital admissions. Concentrating interventions on these drug groups could reduce appreciably the number of preventable drug-related admissions to hospital from primary care.

Preventing drug related morbidity: a process for facilitating changes in practice.

AIM: To describe how quantitative data obtained from applying a series of indicators for preventable drug related morbidity (PDRM) in the electronic patient record in English general practice can be used to facilitate changes aimed at helping to improve medicines management. DESIGN: A multidisciplinary discussion forum held at each practice facilitated by a clinical researcher. SUBJECTS AND SETTING: Eight English general practices. OUTCOME MEASURES: Issues discussed at the multidisciplinary discussion forum and ideas generated by practices for tackling these issues. Progress made by practices after 1, 3, and 6 months. RESULTS: A number of clinical issues were raised by the practices and ideas for moving them forward were discussed. The issues that were easiest and most straightforward to deal with (for example, reviewing specific patient groups) were quickly addressed in most instances. Practices were less likely to have taken steps towards addressing issues at a systems level. CONCLUSIONS: Data generated from applying PDRM indicators can be used to facilitate practice-wide discussion on medicines management. Different practices place different priority levels on the issues they wish to pursue. Individual practice "ownership" of these, together with having a central committed figure at the practice, is key to the success of the process.

Down-regulation of glucose transport by elevated extracellular glucose concentrations in cultured rat aortic smooth muscle cells does not normalize intracellular glucose concentrations.

Vascular disease is a prominent complication of diabetes mellitus, and hyperglycemia has been implicated as a risk factor for the development of these vascular complications. It has previously been suggested that down-regulation of glucose transport in response to hyperglycemia might serve a protective role by decreasing intracellular glucose concentrations. In the present study, regulation of glucose transport by extracellular glucose concentrations was investigated in cultured rat vascular smooth muscle cells (VSMCs). Confluent quiescent VSMCs were exposed to medium containing either normal (5 mmol/L) or elevated (20 mmol/L) extracellular glucose concentrations for 24 hours. VSMCs exposed to elevated extracellular glucose concentrations (with or without serum) for 24 hours exhibited significant decreases in 2-deoxyglucose (2-DG) and D-glucose uptake rates. This decreased glucose transport was associated with a decrease in the Vmax of D-glucose transport without a change in KM. In the absence of serum, a decrease in the quantity of GLUT-1 transport protein at the plasma membrane was noted in cells exposed to elevated extracellular glucose concentrations for 24 hours. Intracellular glucose concentrations were estimated by using two methods, and the results revealed significantly higher intracellular glucose concentrations in the cells exposed to elevated extracellular glucose concentrations for 24 hours. These results suggest that down-regulation of glucose transport in cultured VSMCs exposed to elevated extracellular glucose concentrations for 24 hours does not occur to an extent that normalizes intracellular glucose concentrations. This prolonged increase in intracellular glucose concentrations and the potential associated toxicity may explain the increased incidence of vascular complications in patients with diabetes mellitus.

Presence of chloride-formate exchange in vascular smooth muscle and cardiac cells.

The presence of chloride-formate anion exchange in vascular smooth muscle cells (VSMCs) and cardiac myocytes was investigated. Imposing an outward chloride gradient in sarcolemmal microsomes isolated from canine aorta stimulated [14C]formate uptake compared with the absence of a chloride gradient (24.3 +/- 2.33 versus 9.8 +/- 1.41 pmol/mg protein for 30 seconds, P < .03) and induced transient uphill [14C]formate uptake. The chloride-formate exchange was significantly inhibited in the presence of 1 mmol/L 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) or furosemide (57% and 61%, respectively). Incubation of rat cultured VSMCs in a medium containing [14C]formate resulted in uptake of formate that was significantly DIDS and furosemide sensitive (79.34 +/- 2.47, 43.03 +/- 2.37, and 44.65 +/- 1.68 pmol/mg protein for 4 minutes in control, DIDS, and furosemide groups, respectively). Preincubation of the VSMCs in chloride-free medium significantly reduced the DIDS-sensitive (36.31 versus 16.85 pmol/mg protein for 4 minutes, P < .001) and furosemide-sensitive (34.72 versus 8.78 pmol/mg protein for 4 minutes, P < .001) [14C]formate uptake. These results are compatible with the presence of chloride-formate exchange in VSMCs. Influx of [14C]formate into sarcolemmal vesicles isolated from canine heart was significantly higher in the presence of an outward chloride gradient than in its absence (18.1 +/- 2.3 versus 9.6 +/- 1.7 pmol/mg protein for 30 seconds, P < .03). The chloride-formate exchange was significantly inhibited in the presence of 1 mmol/L DIDS or furosemide (41% and 52%, respectively). We conclude that the distribution of chloride-formate exchange may be more universal than previously suggested.(ABSTRACT TRUNCATED AT 250 WORDS)

Pathophysiology of vasopressin in edematous disorders.

Sodium and water retention is characteristic of edematous disorders including cardiac failure, cirrhosis, nephrotic syndrome and pregnancy. In recent years the use of a sensitive radioimmunoassay for plasma vasopressin has implicated the role of nonosmotic vasopressin release in the water retention of these edematous disorders. In experimental studies and studies in humans it has been found that the nonosmotic release of vasopressin is consistently associated with activation of the sympathetic nervous and renin-angiotensin-aldosterone systems. Moreover, the sympathetic nervous system has been shown to be involved in the nonosmotic release of vasopressin (carotid and aortic baroreceptors) and activation of the renin-angiotensin system (renal beta-adrenergic receptors). These findings have led to our proposal that body fluid volume regulation involves the dynamic interaction between cardiac output and peripheral arterial resistance. In this context neither total extracellular fluid (ECF) volume nor blood volume are determinants of renal sodium and water excretion. Rather, renal sodium and water retention is initiated by either a fall in cardiac output (e.g. ECF volume depletion, low-output cardiac failure, pericardial tamponade or hypovolemic nephrotic syndrome) or peripheral arterial vasodilation (e.g. high-output cardiac failure, cirrhosis, pregnancy, sepsis, arteriovenous fistulae and pharmacologic vasodilators). With a decrease in effective arterial blood volume (EABV), initiated by either a fall in cardiac output or peripheral arterial vasodilation, the acute response involves vasoconstriction mediated by angiotensin, sympathetic mediators and vasopressin. The slower response to restoring EABV involves vasopressin-mediated water retention and aldosterone-mediated sodium retention. The renal vasoconstriction which accompanies those states that decrease EABV, by either decreasing cardiac output or causing peripheral arterial vasodilation, limits the distal tubular delivery of sodium and water thus maximizing the water-retaining effect of vasopressin and impairing the normal escape from the sodium-retaining effects of aldosterone. The elevated glomerular filtration rate and filtered sodium load in pregnancy allows increased distal sodium and water delivery in spite of a decrease in EABV, thus limiting edema formation during gestation.

A unifying hypothesis of sodium and water regulation in health and disease.

Sodium and water retention is characteristic of edematous disorders including cardiac failure, cirrhosis, nephrotic syndrome, and pregnancy. In recent years, the use of a sensitive radioimmunoassay for plasma vasopressin has implicated the role of nonosmotic vasopressin release in the water retention of these edematous disorders. In experimental studies and studies in man, it has been found that the nonosmotic release of vasopressin is consistently associated with the activation of the sympathetic nervous and renin-angiotensin-aldosterone systems. Moreover, the sympathetic nervous system has been shown to be involved in the nonosmotic release of vasopressin (carotid and aortic baroreceptors) and in the activation of the renin-angiotensin system (renal beta-adrenergic receptors). These findings have led to our proposal that body fluid volume regulation involves the dynamic interaction between cardiac output and peripheral arterial resistance. In this context, neither total extracellular-fluid (ECF) volume nor blood volume are determinants of renal sodium and water excretion. Rather, renal sodium and water retention is initiated by either a fall in cardiac output (e.g. ECF volume depletion, low-output cardiac failure, pericardial tamponade, or hypovolemic nephrotic syndrome) or peripheral arterial vasodilation (e.g. high-output cardiac failure, cirrhosis, pregnancy, sepsis, arteriovenous fistulae, and pharmacologic vasodilators). With a decrease in effective arterial blood volume (EABV). initiated by either a fall in cardiac output or peripheral arterial vasodilation, the acute response involves vasoconstriction mediated by angiotensin, sympathetic mediators, and vasopressin. The slower response to restoring EABV involves vasopressin-mediated water retention and aldosterone-mediated sodium retention. The renal vasoconstriction which accompanies those states that decrease EABV, by either decreasing cardiac output or causing peripheral arterial vasodilation.(ABSTRACT TRUNCATED AT 250 WORDS)

Urinary albumin, transferrin and iron excretion in diabetic patients.

The present study was undertaken to determine urinary and serum iron, transferrin and albumin levels in diabetic patients with varying amounts of proteinuria. A highly significant correlation was found between urinary albumin and transferrin excretion over a wide range of urinary albumin excretion (0.005 to 18 g/g creatinine) (r = 0.972). The urine/serum ratio of transferrin and albumin were identical, documenting a similar glomerular leak and tubule handling for these two proteins. In contrast to the above correlation between transferrin and albumin, there was no correlation between iron and either of these proteins until nephrotic range proteinuria had occurred, and even at that time the correlation was much weaker than that found between the proteins (r = 0.680). Urinary iron excretion increased early in the course of diabetic renal disease, being increased in 3 of 11 patients without proteinuria and in 8 of 10 patients with mild proteinuria. All patients with nephrotic range proteinuria had markedly increased urinary iron excretion (150 +/- 166 micrograms/g creatinine vs. 6.4 +/- 0.7 micrograms/g creatinine in controls) and decreased serum iron levels (592 +/- 189 micrograms/liter vs. 979 +/- 394 micrograms/liter in the control group). The iron/transferrin ratio in urine was consistently greater than the iron/transferrin ratio in plasma at all stages of proteinuria. In patients with both subnephrotic and nephrotic range proteinuria, approximately 35 to 40 micrograms Fe/g creatinine was present in the urine with an excess of transferrin. In conclusion, urinary iron excretion is increased early in the course of diabetic renal disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Cocaine-induced alterations in the density of monoaminergic receptors in the embryonic guinea pig cerebral wall.

Quantitative receptor autoradiography was used to examine the effect of chronic cocaine exposure on the density of alpha1-, alpha2- and beta-adrenergic, 5-HT1A- and 5-HT2-serotonergic, and D1- and D2-dopaminergic receptors in the fetal guinea pig cerebral wall which contained forming motor area of the cerebral cortex. The pregnant guinea pig received two daily subcutaneous injections of 20 mg/kg cocaine beginning on the 20th day of pregnancy (E20). The control animals received injections of equivalent volume of saline. The receptor densities were examined between days 5-30 of the treatment, which corresponds to E25-E50. By the fifth day of treatment (E25), cocaine produced downregulation of all receptors studied throughout the entire depth of the fetal cerebral wall. More extended treatment, however, resulted in recovery of receptor levels. Finally, from days 20-30 of treatment (E40-E50) there was a significant upregulation of noradrenergic and dopaminergic receptor sites. These findings demonstrate that exposure to cocaine in utero can influence adrenergic, serotonergic, and dopaminergic receptors in the embryonic cerebral wall, which may lead to alteration in corticogenesis. Furthermore, the present study reveals that, in the course of chronic treatment, cocaine may completely reverse its receptor regulatory activity in the fetal brain.

Adult and pediatric peritonitis rates in a home dialysis program: comparison of continuous ambulatory and continuous cycling peritoneal dialysis.

We reviewed our 115-month experience with continuous ambulatory peritoneal dialysis (CAPD) and continuous cycling peritoneal dialysis (CCPD) in adult and pediatric patients to determine whether there is a difference in the incidence of peritonitis between patients performing CAPD or CCPD. Peritonitis rates were similar in patients performing CAPD or CCPD in both the adult and pediatric age groups. The overall CAPD peritonitis rate was significantly lower in adult patients when compared with pediatric patients. There was no difference in peritonitis rates for CCPD between adult and pediatric patients. When the data are divided into 3-year subgroups, the incidence of peritonitis is significantly lower in adult patients undergoing either CAPD or CCPD when compared with pediatric patients during the years 1986 to 1988. There is significant improvement over time in the incidence of peritonitis in both adult and pediatric patients performing CCPD; similarly, there is a trend toward improvement in patients performing CAPD. Staphylococcus species organisms remain the most common bacterial cause of peritonitis, except in pediatric patients under the age of 2 years or with nephrostomies, where gram-negative rod infections were more common. Peritonitis resulted in discontinuation of peritoneal dialysis in a greater number of adult patients. These results suggest that the number of catheter manipulations is not important in determining the incidence of peritonitis. Pediatric patients are more likely than adult patients to develop peritonitis with either CAPD or CCPD. Adult patients are more likely than pediatric patients to discontinue peritoneal dialysis secondary to peritonitis.