Comparison of Two Manufacturing Processes of Daprodustat for Bioequivalence and Dissolution in Healthy Volunteers: A Randomized Crossover Study

Daprodustat, an orally bioavailable hypoxia-inducible factor-prolyl hydroxylase enzyme inhibitor, has recently completed phase 3 clinical development for treating anemia of chronic kidney disease. Part A of this 2-part, randomized, double-blind, single-dose, cross-over study (NCT04640311) compared pharmacokinetic properties of a single oral dose of daprodustat 4 mg tablets manufactured via twin-screw wet granulation (process 1) to 2 sets of 4 mg tablets manufactured via high-shear wet granulation (process 2), to assess the impact of different dissolution profiles on pharmacokinetics. Part B assessed the bioequivalence of daprodustat tablets manufactured via process 1 with tablets manufactured via process 2 at 5 different dose strengths (1, 2, 4, 6, and 8 mg). In part A, mean plasma concentrations of daprodustat were comparable over a 24-hour period despite differences in manufacturing processes and dissolution profiles. In part B, the 90% confidence intervals of the ratios of the least squared means for area under the concentration-time curve and maximum observed plasma concentration fell within the 0.8-1.25 bioequivalence range for all doses, except for maximum observed plasma concentration at 8 mg. A prespecified sensitivity analysis jointly assessing all doses showed bioequivalence for all doses tested. No new safety concerns for daprodustat were identified.

Patient experiences with a phone-based cardiovascular risk reduction intervention: Are there differences between women and men?

OBJECTIVES

To explore gender-based differences in experiences with a telehealth-delivered intervention for reduction of cardiovascular risk.

METHODS

We conducted 23 semi-structured qualitative interviews by telephone with 11 women and 12 men who received a 12-month, pharmacist-delivered, telephone-based medication and behavioral management intervention. We used content analysis to identify themes.

RESULTS

We identified three common themes for both men and women: ease and convenience of phone support, preference for proactive outreach, and need for trust building in the context of telehealth. While both genders appreciated the social support from the intervention pharmacist, women voiced appreciation for accountability whereas men generally spoke about encouragement.

CONCLUSIONS

Rapport building may differ between telehealth and in-person healthcare visits; our work highlights how men and women's experiences can differ with telehealth care and which can inform the development of future, purposeful rapport building activities to strengthen the clinician-patient interaction.

PRACTICE IMPLICATIONS

Clinicians should seek opportunities to provide frequent and routine support for patients with chronic disease. Telehealth interventions may benefit from gender-specific tailoring of social support.

Adolescent Clinical Development of Ezogabine/Retigabine as Adjunctive Therapy for Partial-Onset Seizures: Pharmacokinetics and Tolerability

OBJECTIVES: To explore the pharmacokinetic (PK) profile and safety of ezogabine (EZG)/retigabine (RTG) as adjunctive therapy for uncontrolled partial-onset seizures (POS) in adolescents. METHODS: In this multiple-dose study (NCT01494584), adolescents with POS received EZG/RTG immediate-release tablets three times daily (TID) as adjunctive therapy to 1 to 3 concurrent antiepileptic drugs. The study comprised a screening phase, and a 5- to 8-week treatment phase starting with 100 mg TID up-titrated once weekly by ≤50 mg TID to a maximum dosage of 300 mg TID. There were 8 venous blood samples and 2 finger-prick blood samples collected for PK analysis during 8-hour time periods at the target dosages of 100, 200, and 300 mg TID. RESULTS: This study was terminated prematurely on US Food and Drug Administration advice due to pigmentation/discoloration findings in long-term, open-label extension studies in adults. Five participants (ages 13-16 years) had enrolled in the study. For the EZG/RTG 100-, 200-, and 300-mg doses, the area under the concentration-time curve during the dosage intervals was 1680, 2559, and 3784 ng/hr/mL; maximum plasma concentrations were 370, 536, and 751 ng/mL, and minimum plasma concentrations were 105, 200, and 287 ng/mL, respectively. Venous and finger-prick concentrations of EZG/RTG were similar. No significant adverse events were observed during treatment (133-213 days). CONCLUSIONS: EZG/RTG PK appeared linear across the dosage range of 100 to 300 mg TID in adolescents with POS, and were consistent with adult observations. The small sample size and short study duration preclude conclusions regarding the safety and efficacy of EZG/RTG.

Selective sodium-dependent glucose transporter 1 inhibitors block glucose absorption and impair glucose-dependent insulinotropic peptide release

GSK-1614235 and KGA-2727 are potent, selective inhibitors of the SGLT1 sodium-dependent glucose transporter. Nonclinical (KGA-2727) and clinical (GSK-1614235) trials assessed translation of SGLT1 inhibitor effects from rats to normal human physiology. In rats, KGA-2727 (0.1 mg/kg) or vehicle was given before oral administration of 3-O-methyl-α-d-glucopyranose (3-O-methylglucose, 3-OMG) containing 3-[3H]OMG tracer. Tracer absorption and distribution were assessed from plasma, urine, and fecal samples. SGLT1 inhibition reduced urine 3-OMG recovery and increased fecal excretion. SGLT1 inhibitor effects on plasma glucose, insulin, gastric inhibitory peptide (GIP), and glucagon-like peptide-1 (GLP-1) concentrations were also measured during a standard meal. Incremental glucose, insulin, and GIP concentrations were decreased, indicating downregulation of β-cell and K cell secretion. Minimal effects were observed in the secretion of the L cell product, GLP-1. With the use of a three-way, crossover design, 12 healthy human subjects received placebo or 20 mg GSK-1614235 immediately before or after a meal. Five minutes into the meal, 3-OMG was ingested. Postmeal dosing had little impact, yet premeal dosing delayed and reduced 3-OMG absorption, with an AUC0-10 of 231±31 vs. 446±31 μg·h(-1)·ml(-1), for placebo. Recovery of tracer in urine was 1.2±0.7 g for premeal dosing and 2.2±0.1 g for placebo. Incremental concentrations of insulin, C-peptide, and GIP were reduced for 2 h with premeal GSK-1614235. Total GLP-1 concentrations were significantly increased, and a trend for increased peptide YY (PYY) was noted. SGLT1 inhibitors block intestinal glucose absorption and reduce GIP secretion in rats and humans, suggesting SGLT1 glucose transport is critical for GIP release. Conversely, GLP-1 and PYY secretion are enhanced by SGLT1 inhibition in humans.

Randomized clinical trial of vertical or transverse laparotomy for abdominal aortic aneurysm repair

BACKGROUND

The objective of this randomized trial was to evaluate the incidence of incisional hernia after transverse or vertical incisions for open aortic aneurysm repair.

METHODS

The study group comprised 69 patients who underwent elective aneurysm repair between November 1998 and November 2000 (60 men, nine women; mean age 72.8 (range 56-95) years). Patients were randomized to a transverse (n = 32) or vertical (n = 37) incision for the procedure. Of the 42 patients who were still alive in February 2004, 37 (15 transverse, 22 vertical incisions) attended for review. Laparotomy scars were assessed both clinically and ultrasonographically by the same examiner, to look for incisional hernia.

RESULTS

Mean follow-up was 4.4 years. A multivariable logistic regression analysis revealed that the type of incision was the only parameter that significantly influenced the rate of incisional hernia: six of 15 patients with a transverse laparotomy versus 20 of 22 with a vertical laparotomy (P = 0.010).

CONCLUSION

The incidence of incisional hernia was high after aortic aneurysm repair, but was lower in patients who had a transverse incision.

Roles of residues 3 and 4 in cyclic tetrapeptide ligand recognition by the kappa-opioid receptor

A series of cyclic, disulfide- or dithioether-containing tetrapeptides based on previously reported potent mu- and delta-selective analogs has been explored with the aim of improving their poor affinity to the kappa-opioid receptor. Specifically targeted were modifications of tetrapeptide residues 3 and 4, as they presumably interact with residues from transmembrane helices 6 and 7 and extracellular loop 3 that differ among the three receptors. Accordingly, tetrapeptides were synthesized with Phe(3) replaced by aliphatic (Gly, Ala, Aib, Cha), basic (Lys, Arg, homo-Arg), or aromatic sides chains (Trp, Tyr, p-NH(2)Phe), and with d-Pen(4) replaced by d-Cys(4), and binding affinities to stably expressed mu-, delta-, and kappa-receptors were determined. In general, the resulting analogs failed to exhibit appreciable affinity for the kappa-receptor, with the exception of the tetrapeptide Tyr-c[d-Cys-Phe-d-Cys]-NH(2), cyclized via a disulfide bond, which demonstrated high binding affinity toward all opioid receptors (Ki(mu) = 1.26 nm, Ki(delta) = 16.1 nm, Ki(kappa) = 38.7 nm). Modeling of the kappa-receptor/ligand complex in the active state reveals that the receptor-binding pocket for residues 3 and 4 of the tetrapeptide ligands is smaller than that in the mu-receptor and requires, for optimal fit, that the tripeptide cycle of the ligand assume a higher energy conformation. The magnitude of this energy penalty depends on the nature of the fourth residue of the peptide (d-Pen or d-Cys) and correlates well with the observed kappa-receptor binding affinity.

Is screening of abdominal aortic aneurysm effective in a general practice setting?

AIM

This prospective study was conducted to assess feasibility, patients' acceptability and impact of ultrasound screening on rupture rate of abdominal aortic aneurysms (AAAs).

METHODS

A population based sample of men (n=2709), aged over 60 years, covering 11 general practices was offered ultrasound screening between January 1996 and December 2003. The presence of risk factors for arteriosclerosis and annual rupture rates for AAAs were analyzed.

RESULTS

Of the 2709 patients approached, 2561 (95%) accepted and 161 (6%) did not attend. A total number of 81 (3.4%) patients (average age: 71 years) were identified with an AAA, of which 59 were small (<5 cm) and 22 large AAAs (>5 cm). The most common risk factors identified in patients with AAA were smoking/ex-smoking (n=68, 84%) and hypertension (n=32, 40%). The overall annual rupture rate was reduced from 47% in 1996 to 14% in 2003.

CONCLUSIONS

Ultrasound screening for AAA is feasible, acceptable by elderly male patients in a primary care setting and reduces the incidence of ruptured AAAs.

Quality of Life in Patients Treated with First-Line Antiretroviral Therapy Containing Nevirapine And/Or Efavirenz

Objective

To assess whether differences in safety profiles between nevirapine (NVP) and efavirenz (EFV), as observed in the 2NN study, translated into differences in ‘health related quality of life’ (HRQoL).

Design

A sub-study of the 2NN study, with antiretro-viral-naive patients randomly allocated to NVP (once or twice daily), EFV or NVP+EFV, in addition to stavudine and lamivudine.

Methods

Comparing differences in changes of HRQoL over 48 weeks as measured with the Medical Outcomes Study HIV Health Survey (MOS-HIV) questionnaire, using analysis of variance.

Results

The 2NN study enrolled 1216 patients. No validated questionnaires were available for 244 patients, and 55 patients had no HRQoL data at all, leaving 917 patients eligible for this sub-study. A total of 471 (51%) had HRQoL measurements both at baseline and week 48. The majority (69%) of patients without HRQoL measurements did, however, complete the study. The change in the physical health score (PHS) was 3.9 for NVP, 3.4 for EFV and 2.4 for NVP+EFV ( P=0.712). For the mental health score (MHS) these values were 6.1, 7.0 and 3.9, respectively ( P=0.098). A baseline plasma HIV-1 RNA concentration (pVL) ≥100 000 copies/ml and a decline in pVL (per log10) were independently associated with an increase of PHS. An increase of MHS was only associated with pVL decline. Patients experiencing an adverse event during follow-up had a comparable change in PHS but a significantly smaller change in MHS, compared with those without an adverse event.

Conclusions

First-line ART containing NVP and/or EFV leads to an improvement in HRQoL. The gain in HRQoL was similar for NVP and EFV, but slightly lower for the combination of these drugs.

Bioavailability of fluticasone propionate and mometasone furoate aqueous nasal sprays

OBJECTIVES

To compare the systemic exposure for intranasal mometasone furoate (MF) and fluticasone propionate (FP) aqueous nasal sprays (ANS) in terms of serum and urinary cortisol parameters and plasma pharmacokinetics.

METHODS

Twelve healthy subjects completed this three-way, cross-over study. They received FPANS (50 microg/spray), MFANS (50 microg/spray) or placebo ANS, eight sprays per nostril every 8 h for 4 days. Cortisol measurements were made at baseline and day 4. FP and MF plasma concentrations were also measured on day 4.

RESULTS

MFANS produced similar mean plasma AUC (123 pmol/l h) to FPANS (112 pmol/l h). Despite the use of high doses, necessary to generate adequate pharmacokinetic data, only minor reductions in cortisol parameters were found, with no difference between FPANS and MFANS.

CONCLUSIONS

FP and MF have similar and very low systemic bioavailability when administered intranasally using a high-dose regimen. It is therefore unlikely that therapeutic doses of intranasal FP or MF will produce dissimilar or significant degrees of systemic exposure or systemic effects.

Randomized prospective comparison of postoperative pain control and respiratory complications following midline or transverse laparotomy for aortic surgery

Background

Transverse abdominal incisions are thought to be less painful and followed by fewer pulmonary complications than midline incisions, but reports remain controversial. This study compared midline and transverse incisions for elective transabdominal aortic aneurysm repair with respect to postoperative pain, respiratory function and pulmonary complications.

Methods

Sixty patients were randomized to midline laparotomy and transverse incisions, and evaluated before and after operation for 7 days at regular intervals. Analgesia was provided via a thoracic epidural and pain scores were recorded by means of a visual analogue scale. Respiratory function (peak expiratory flow rate, forced expiratory volume in 1 s and forced vital capacity) and pulmonary complications were monitored as well as patient characteristics, operating time, blood loss, operative exposure, and length of stay on the intensive care unit (ITU) and in hospital.

Results

The two groups included a similar number of patients (n = 30 per group) and basic characteristics such as age and preoperative risk factors. Linear analogue pain scores were significantly lower in the transverse group of patients (P &lt; 0·001). There was no significant difference between the two groups with regard to postoperative ventilatory function and respiratory complications as well as analgesic requirements, operating time, blood loss, and length of ITU and hospital stay.

Conclusion

The direction of incision does not seem to influence the incidence of respiratory complications. However, a transverse incision in combination with a high epidural analgesia seems to offer better postoperative pain control.

Extraperitoneal laparoscopic aortic control with endovascular visualization of a stent-graft combination

OBJECTIVES

to demonstrate the feasibility of minimally invasive approaches to the aorta using retroperitoneal laparoscopy and to clamp the aorta to give views for perfemoral aortic angioscopy.

METHODS

using retroperitoneal laparoscopy facilitated by balloon dissection the authors developed a new approach to the infrarenal abdominal aorta, in six pigs, to allow control of aortic blood flow. Aortic stent-grafts were then deployed via femoral arteriotomy, and after flushing the blood from the aorta, the stent-grafts were visualized by angioscopy.

RESULTS

accurate positioning and patency of the stent-grafts was ascertained by direct vision angioscopy in all cases.

CONCLUSIONS

this series shows that extraperitoneal laparoscopic aortic dissection is feasible and direct endovascular visualization of the aortic lumen can be performed. This may find a role as an adjunct to endovascular techniques such as endovascular stent-graft placement, by aortic angioscopy following minimally-invasive aortic clamping.

The effect of a single or repeated period of high stocking density on the behavior and response to stimuli in broiler chickens

Broiler chickens are normally housed at a fixed number per unit area throughout their life, which reduces their opportunity for movement during the later stages of rearing. An experiment is described that exposed broilers to a high stocking density either once or twice in the rearing period, and investigated the effects on the birds' behavior, and the response to other birds and humans after the second exposure to high or low stocking density. The stocking density was increased from a low level (1.7 kg/m2) to a high level (14 kg/m2) for the 2nd and/or 4th wk of rearing, or left unchanged at the low level. When stocked at the low rate, the birds spent more time walking and sitting and less time dozing and sleeping. They pecked more at inanimate objects and interacted more with other birds, but this did not include aggressive interaction. The effects of stocking density on behavior were greater in Week 4 than in Week 2, but there was no evidence that exposure to a high stocking density in Week 2 influenced the birds' behavioral response to a high stocking density in Week 4. Where stocking density did affect behavior in both Weeks 2 and 4, there was evidence of the response being cumulative. The activity of birds in the presence of another bird restrained in an open field arena was greatest when they had been stocked at the low density throughout the experiment. When a familiar person was in the arena, the birds that had been stocked at the high density in Week 2 were most active, but these birds showed the longest tonic immobility when inverted in a cradle. It is concluded that a high stocking density reduces activity in broiler chickens, and that birds stocked at a high density early in the rearing period are most active in the presence of people and show the longest tonic immobility in response to a fearful stimulus.

Randomised study of sterile versus non-sterile urethral catheterisation

Indwelling urethral catheters are the most common cause of urinary tract infections (UTI), yet there is no direct evidence that technique of catheter insertion affects this. In a prospective study, 156 patients underwent preoperative urethral catheterisation, randomly allocated to 'sterile' or 'clean/non-sterile' technique groups. There was no statistical difference between the two groups with respect to the incidence of UTI. There was a considerable cost difference between the two groups, the 'sterile' method being over twice as expensive as the 'clean' method. Strict sterility is not necessary in preoperative short-term urethral catheterisation and is more expensive and time consuming.

Assessment of feasibility for endovascular prosthetic tube correction of aortic aneurysm

Abdominal aortic aneurysm (AAA) can now be corrected by perfemoral introduction of a prosthetic tube graft with fixation using expandable metal stents. This technique requires a satisfactory iliac system, through which the graft can reach its destination, and suitable lengths of non-aneurysmal aorta below the renal arteries and above the aortic bifurcation for stent attachment. The feasibility for placement of endovascular grafts was assessed in 44 consecutive patients admitted for transabdominal AAA repair. The proximal and distal aneurysmal necks and the iliac arteries were assessed before operation by colour flow Doppler ultrasonography (duplex scanning), computed tomography and intravenous digital subtraction angiography, using intraoperative measurements as the 'gold standard'. At operation 32 of 44 patients had a suitable proximal neck and five of 44 a suitable distal neck for endovascular grafting. Duplex scanning was the most accurate modality for preoperative assessment of the aneurysm necks. According to this technique 32 of 44 patients had a satisfactory iliac system for introduction of an endovascular graft. Overall only four of 44 patients were considered suitable for endovascular correction of AAA using a tube graft-stent combination.

In vitro evaluation of endovascular stents to assess suitability for endovascular graft fixation

OBJECTIVE

To compare and ascertain the suitability for endovascular aortic graft fixation of the Palmaz stent, the Strecker stent, the modified Gianturco-Z stent, the Wallstent and a new stent made of the shape memory alloy nitinol. DESIGN, SETTING AND MATERIALS: In vitro studies using a simple tensiometer to assess the forces required to distract each stent from porcine aorta; and using a high-pressure, pulsatile-flow pump to measure flow rates required to dislodge stents holding grafts within porcine aortas, with assessment using endovascular ultrasound.

RESULTS

The Palmaz, the modified Gianturco-Z and the nitinol stents resisted significantly greater distraction forces than the Wallstent, but endovascular ultrasound examination revealed that the modified Gianturco-Z stent was seen to move away from the aortic wall at high flow rates precluding adequate fixation. The Strecker stent could not be assessed using these techniques.

CONCLUSIONS

A nitinol stent may be suitable for aortic graft fixation, has characteristics similar to the Palmaz stent and has shape memory effect which may overcome the difficulties of introduction of wider diameter stents through narrow arteries.

One lung ventilation in endoscopic transthoracic sympathectomy

Endoscopic transthoracic sympathectomy currently requires one lung anaesthesia to facilitate access to the thoracic sympathetic chain. This may cause reduced perioperative arterial oxygen saturation. We describe a series of patients in which the collapsed lung is kept partially inflated using continuous positive airway pressure (CPAP) with 100% oxygen. This modification of anaesthetic technique enabled a normal arterial oxygen saturation to be maintained thus preventing operative delays whilst the lung was reinflated to restore adequate oxygen saturation.

Retroperitoneoscopy: the balloon technique

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Laparoscopic knot substitutes. An assessment of techniques of securing sutures through the laparoscope

Advanced interventional laparoscopy has required the development of new methods of securing sutures as alternatives to the three-throw reef knot. A tensiometer was designed to measure the forces required for distraction of various knots or securing devices with different sutures. A three-throw reef knot was used as a control. Each device was tested 15 times, and the tension at which the "knot" slipped was recorded. Titanium clips (Ligaclip, Ethicon), locking polydioxanone clips (Absolok and Lapra-ty, Ethicon), malleable collars, Roeder knots and biocompatible glue (Histoacryl, B Braun Melsungen AG) were all assessed. Sutures secured with Ligaclips, Absolok clips and glue were significantly weaker than the three-throw reef knot. Sutures secured with malleable collars and Lapra-ty clips were as strong as the three-throw reef knot and have potential for use as knot substitutes.

A novel means of securing a laparoscopic port in the obese patient

Advanced interventional laparoscopy has necessitated the development of a vast array of new equipment, but inevitably some of this equipment has had to be adapted to specific patient needs. Standard laparoscopic ports may be too short for use in obese patients. We describe a technique using a Portex endotracheal tube as an over-tube, which will overcome this problem.

A service chief model for general pediatric inpatient care and residency training

Pediatric training programs are faced with rapid, fundamental changes in hospital practice and an increasingly rigorous regulatory and fiscal environment. Traditional models for providing care and teaching students and house officers may not be sufficiently responsive to these challenges. In 1986, the Department of Medicine at Children's Hospital, Boston, reorganized the general inpatient program and implemented a "service chief" system adapted from British hospital "firms." Three age-based inpatient services (Thomas Morgan Rotch infant/toddler service, Kenneth Daniel Blackfan school-age service, and Charles Alderson Janeway adolescent/young adult service) were created, each headed by an experienced clinician and teacher (service chief). The service chiefs developed age-appropriate curricula, recruited a balanced faculty of generalists and specialists to serve as attending physicians and provide teaching in their areas of expertise, and established strong collaborative relationships with nurse managers on their respective wards. Implementation of the service chief system has been associated with development of faculty esprit de corps, standardized tracking of faculty performance, enhanced supervision and counseling of housestaff, and improved continuity of patient care. Relationships with referring physicians have improved dramatically, as measured by formal satisfaction surveys. Accountability and documentation have been emphasized, and departmental billings have increased sharply. Ongoing quality indicators have been developed, and collaborative patient care, teaching, and quality-improvement projects have been initiated with the nursing staff. Naming the services for distinguished past physicians-in-chief has provided a focus for fund-raising.(ABSTRACT TRUNCATED AT 250 WORDS)

Chest wall reconstruction after resection of recurrent breast tumours

A series of 13 chest wall resections for recurrent breast tumours are reported, the defects being closed by synthetic prostheses. In nine patients the prostheses were covered by a latissimus dorsi flap, while in the last eight patients a rigid 'shield' prosthesis of methyl methacrylate was used, and a stable chest obtained. Mechanical ventilation for more than 24 h was not required in those patients in whom a shield was used.

Distribution of trace element pollutants in a contaminated grassland ecosystem established on metalliferous fluorspar tailings. 1: lead

Concentrations of lead in vegetation, invertebrates and small mammals in a grassland ecosystem evolved from a mine waste revegetation scheme indicated the high concentration of lead in the original tailings. Lead levels in invertebrates reflected dietary concentrations and feeding strategy, a pattern also true of the indigenous small mammals. Total body and tissue concentrations of lead in the herbivorous Microtus agrestis L. (field vole) and insectivorous Sorex araneus L. (common shrew) were significantly higher in the contaminated grassland than in an uncontaminated area, but concentration ratios (body:diet) were less than unity and there was no evidence of age-dependent accumulation of lead.

Distribution of trace element pollutants in a contaminated ecosystem established on metalliferous fluorspar tailings. 3: fluoride

High total soil fluoride (10 000 microg g(-1)) in the metalliferous fluorspar tailings was reflected by elevated concentrations in standing live vegetation (300-1000 microg g(-1)); plant roots (c. 6000 microg g(-1)); plant litter (c. 4000 microg g(-1)); total body concentrations of invertebrates (400-4000 microg g(-1)) and the small mammals Microtus agrestis (120-360 microg g(-1)) and Sorex araneus (140-250 microg g(-1)). Seasonal changes in the standing live vegetation and the availability of soil fluoride to plants are discussed. Seasonal changes in total body concentrations of the small mammals were related to the age structure of the populations as well as dietary levels. In the small mammals, the concentration ratios were < 0.5 at the tailings dam and > 1.1 at the control site, indicating that both species were able to regulate fluoride accumulation at the higher levels of intake. Soft tissue concentrations were, as expected, very low compared to the hard tissues but, still, were generally significantly higher at the tailings dam compared to the control site. Evidence of dental fluorosis was found in Microtus agrestis, but not Sorex araneus.

Distribution of trace element pollutants in a contaminated grassland ecosystem established on metalliferous fluorspar tailings. 2: Zinc

Concentrations of zinc in vegetation, invertebrates and small mammals in a grassland ecosystem derived from a mine waste vegetation scheme indicated the high concentration of zinc in the original tailings. However, the considerable differences in soil and vegetation zinc concentrations between the tailings and an uncontaminated site were not reflected in the invertebrate and small mammal communities. Invertebrate zinc levels and total body concentrations in Microtus agrestis L. (field vole) and Sorex araneus L. (common shrew) suggested a notable buffering of zinc absorption and tissue accumulation in the presence of substantially elevated dietary zinc. In the small mammals the skeleton appeared to function as the major storage site for zinc, possibly contributing to homeostasis in the soft tissues.

The metabolism and disposition of [2-14C]diazepam in the streptozotocin-diabetic rat

The oral administration of [2-14 C]diazepam to streptozotocin (STZ)-diabetic rats resulted in decreased faecal and biliary levels of metabolites with a concomitant rise in urinary radioactivity when compared to control values. This situation was reversible upon insulin treatment. The increased urinary metabolite excretion could not be ascribed to the diuresis observed in STZ-diabetic rats. No alteration in the phase I or II routes of [14C]diazepam metabolism in diabetic animals was observed either in vivo or in vitro. Following i.v. administration of [2-14C]diazepam, blood 14C levels in diabetic rats were elevated above those observed in normal animals.