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Biomedical subjects

J T Jørgensen

Publications and source records attributed to J T Jørgensen.

12 recordsLinked to original sources
PubMed2001

Response of cortical bone to antiresorptive treatment.

A total of 113 postmenopausal women (69 controls, 33 using hormone replacement therapy (HRT), and 11 using bisphosphonate) were evaluated twice over 2 years with a new noninvasive, radiogrammetry-based technique called digital X-ray radiogrammetry (DXR) and conventional bone densitometry of the spine, hip, and forearm. Longitudinal changes in bone densitometry were compared with changes captured by DXR: BMD evaluated by DXR (BMDDXR), cortical thickness of the second metacarpal (CTMC2), and porosity of cortical bone. The expected annual postmenopausal reduction in BMD in the control group was detected by BMDspine (-0.8%, P < 0.01), BMDhip (-1.6%, P < 0.001), BMDforearm (-1.5%, P < 0.001), DXR-BMD (-0.8%, P < 0.001), and CTMC2 (-1.1%, P < 0.001). In the HRT group, smaller reductions were seen in BMDDXA, but only significant at the hip (-1.0%, P < 0.01) and distal forearm (-1.0%, P < 0.02). In the bisphosphonate group, cortical porosity was significantly reduced (P < 0.025). Comparing longitudinal changes in age-matched subsamples of controls and bisphosphonate treated, BMDDXR, CTMC2, and porosity of cortical bone all differed significantly (P < 0.01, P < 0.05, P < 0.05, respectively), whereas the BMDDXA measurements did not. In conclusion, DXR provides a densitometry equivalent measurement of the distal forearm and hand and seems to offer new information on the porosity of cortical bone. This may prove useful in the evaluation of bone loss and offer new insight into the effects of different antiresorptive treatment regimens used in the prevention of osteoporosis.

Absorptiometry, Photon↗
PubMed2001

A normative reference database study for Pronosco X-posure System.

Cortical width from radiographs has been used for more than 40 yr as a means of estimating bone strength. In the last 5-10 yr, increased availability of computers and the development of automated algorithms for image assessment have led to an increased interest in radiogrammetry. In this study, we examined a new radiogrammetry device, the Pronosco X-posure System, which estimates bone mineral density (BMD) from forearm/hand radiographs. We obtained hand and forearm radiographs and performed dual X-ray absorptiometry (DXA) at the wrist and hip on 832 women ages 20-79 at four clinical centers across the United States. We then used the X-posure System to estimate BMD (DXR-BMD). The goal of the study was to establish reference ranges for the method and to compare the measurement to DXA measurements of BMD at the wrist and hip. Using statistical models, we estimated that the peak value for DXR-BMD occurred at age 38 (mean = 0.598 g/cm2, standard deviation = 0.034 g/cm2). The correlation between DXR-BMD and DXA was 0.90 at the wrist and 0.61 at the hip. The relationship of DXR-BMD to reported history of fracture was of similar magnitude to that for DXA at the wrist and hip. The strong correlation of DXR-BMD from the X-posure System with DXA at the wrist from the Hologic machine suggests that the X-posure System may be an alternative to DXA at the wrist for the assessment of osteoporosis.

Absorptiometry, Photon↗
PubMed2000

Digital X-ray radiogrammetry: a new appendicular bone densitometric method with high precision.

The precision of any given method for measurement of bone mineral density (BMD) is important in relation to the interpretation of repeated measurements over time, e.g. to monitor the course of suspected osteoporosis or follow the effect of therapy. In the present study a new bone densitometer using the digital X-ray radiogrammetry (DXR) method (Pronosco X-posure Systemtrade mark) is investigated with respect to its short-term precision. The study was carried out on two groups of females, one consisting of 20 women between the ages of 30 and 40, and the other of 20 post-menopausal women above the age of 64. The mean age of the premenopausal women was 35.2 years and the mean DXR BMD was 0.578 g cm-2. The mean age of the post-menopausal women was 68.2 years and the mean DXR BMD was 0.489 g cm-2. The short-term precision of the two groups was evaluated using the coefficient of variation (CV%) and corresponding 90% confidence intervals. The coefficient of variation in the premenopausal group was 0.68% with a 90% confidence interval of 0. 57%-0.83%. The coefficient of variation in the postmenopausal group was 0.61% with a 90% confidence interval of 0.52-0.75%. It can be concluded from the present study that the short-term in vivo precision error of the DXR method is low in both pre- and post-menopausal women. When the results of the study are compared to data reported in the literature, the performance of the DXR method seems to be at least equivalent with peripheral DXA.

Adult↗
PubMed1995

Automatic needle insertion diminishes pain during growth hormone injection.

Non-compliance in children receiving growth hormone (GH) treatment is often caused by pain on injection and difficulties in administration of GH. It has been suggested that automatic needle insertion diminishes pain perception. We quantitatively measured pain intensity on injection with two prototype pens for GH administration, providing either manual or automatic sc needle insertion, using a combined visual analogue/facial scale and a five-item scale in 18 children. With the automatic pen there was a significantly lower maximum pain score compared with the manual pen (median 28.5 versus 52.0 mm) as well as a lower mean pain score (mean 13.7 versus 23.5 mm). The five-item scale revealed that automatic needle insertion was significantly less painful than manual insertion and 13 patients chose to continue treatment with the automatic pen. In conclusion, pain during GH injection can be significantly diminished by automatic needle insertion, which may improve compliance in long-term GH treatment.

Adolescent↗
PubMed1991

Patient acceptance of Nordiject: a new drug delivery system for growth hormone.

Twenty-seven children, aged 5-20 years, with growth retardation were enrolled in an open study to evaluate the acceptability of a new injection pen (Nordiject 24, Novo Nordisk A/S) for administration of recombinant human growth hormone (r-hGH). Prior to this study, 17 of the patients had been receiving treatment with r-hGH administered via syringes and vials; their experiences with this conventional technique have been used for comparison with Nordiject. The injection pen is provided with a replaceable 27-gauge needle and a cartridge containing 24 IU of reconstituted r-hGH (12 IU/mL). A benzyl alcohol 0.9% solution is used as the solvent for the reconstitution. The pen can be regulated for doses from 0.5 to 8 IU per injection; regulation is accomplished by a turning movement. The patients had no problems with the dissolving procedure or handling the pen. Nearly two-thirds of the patients experienced less injection pain with the pen as compared with the syringe. Special attention was paid to local tolerability, which was reported to be good. The thigh was the preferred injection site. The residual contents from 68 cartridges returned by the patients were analyzed for microbial contamination. Contamination was detected in only one cartridge, which could not be confirmed in a repeated test. Because of the simplification of the injection procedure afforded by the injection pen, 20 of 27 patients were able to perform the injections themselves and hence assume a more active role in their treatment. The patients who previously had been using conventional syringes strongly preferred the pen, and all patients wished to continue using the device.

Adolescent↗
PubMed1989

Growth hormone administration by means of an injection pen.

We have evaluated the pharmacokinetics, reliability and patient tolerability of a newly developed injection pen for cartridged growth hormone (GH). The cartridge contains 25 IU GH in 2 ml solvents. The pen, which is basically a needle, syringe and vial in one piece, is operated by a turning movement and allows doses from 0.25-4 IU. Nine GH deficient patients were hospitalized twice for overnight bloodsampling following subcutaneous injections (at 8 p.m.) of GH: i.e. when using traditional syringe and vial and after 6 weeks of use of the pen. Serum GH antibodies were measured immediately prior to, and 3 and 6 months following pen treatment. GH containers were collected regularly from the patients for chemical analysis. A questionnaire was completed during and at the end of the study. The absorption rate and bioavailability of GH tended to be higher with syringe and vial (2 P = 0.07) but there were no differences in the profiles of IGF-I, insulin, glucagon or pertinent metabolic parameters following the 2 injection modes. No GH antibodies occurred during 6 months of pen treatment. The content of polymeric GH was lower in the cartridges (2 P less than 0.001). Seven of the patients reported less injection pain when using the injection pen, which they all strongly preferred and wished to continue using. We conclude that the GH injection pen is a reliable tool which seems to be more convenient for the patients.

Growth Hormone↗
PubMed1988

NPH insulin administration by means of a pen injector.

In an open randomized cross-over study 50 patients with insulin-dependent diabetes were allocated to 3 months of treatment with NPH insulin either by means of a pen injector (Insuject-X) or by conventional syringes. The needle of the NPH pen injector was removed immediately after use to avoid possible leakage of solvent. Ambulatory control was assessed every 6 weeks, including blood sampling (HbA1c and insulin antibodies) and recording of hypoglycaemia. NPH insulin containers were collected for insulin potency measurement by HPLC. A seven-point blood glucose profile was performed fortnightly by means of home blood glucose monitoring. At the end of the 6 months a questionnaire was completed. No significant changes occurred in HbA1c (difference 0.1 +/- 0.7 (SD)%), blood glucose profile, or the incidence of hypoglycaemic episodes on the two regimens. The concentration of NPH insulin in the containers remained constant. All but two of the patients preferred to continue to use the pen injector. This NPH pen injector is a reliable and efficacious tool which may also prove more convenient for the patients.

Blood Glucose↗
PubMedDate not supplied

Development, production and pharmacodynamics of human growth hormone.

With the advent of recombinant DNA technology, it is possible to produce biosynthetic human growth hormone (B-hGH). Novo Nordisk A/S has developed a method for manufacturing B-hGH which is identical to the 22K fraction of pituitary human growth hormone (P-hGH), using a nonpathogenic strain of Escherichia coli as host. B-hGH has been investigated extensively in physical, chemical and biological studies and found to be identical to P-hGH. Pharmacological studies have revealed that B-hGH possesses the same pharmacokinetic and short-term metabolic profiles as P-hGH. Long term clinical studies have shown that B-hGH induces a significant increase in height velocity in children with growth hormone deficiency (GHD) and is characterized by a low antigenicity.

Animals↗
PubMedDate not supplied

Growth hormone therapy with a new delivery system.

Until recently the general regimen for treatment of growth hormone deficient (GHD) children consisted of 2 to 3 intramuscular (i.m.) injections per week using conventional syringes and vials. However, studies within the last 5-10 year have shown that by dividing the same total weekly dosage into daily subcutaneous (s.c.) injections it is possible to achieve a significantly increased growth rate. To make it more feasible for the patients and the parents to cope with this increased number of injections, an injection pen system (Nordiject) for administration of B-hGH has been developed. The Nordiject pen has been investigated both with respect to patient acceptance and bioavailability of the B-hGH (Norditropin) injected with the device. Twenty-seven children with growth retardation were included in a study. The patients had no problems with the handling of the pen and approximately 2/3 of them experienced less injection pain with the pen compared to the syringe. Those patients who had previously been using conventional syringes strongly preferred the pen, and all wished to continue using the device. Fourteen adult GHD patients were included in a randomized cross-over study for investigation of bioavailability. Two separate s.c. injections of 4 IU of B-hGH (Norditropin) each were administered in random order by means of either syringe (4IU/ml) or injection pen (Nordiject) (12 IU/ml). On the basis of this study it was concluded that the bioavailability of B-hGH, measured as AUC, Cmax, and tmax, is equal following injection with the pen to that of injection by syringe.

Adult↗
PubMedDate not supplied

Pain assessment of subcutaneous injections.

OBJECTIVE: To compare injection pain after subcutaneous administration of four different solution volumes. DESIGN: Double-blind, randomized, prospective, multiple crossover study. SETTING: Steno Diabetes Center, Gentofte, Denmark. PARTICIPANTS: Eighteen healthy volunteers, 9 women and 9 men, aged 21-30 years. METHODS: The subjects were injected with four different volumes (0.2, 0.5, 1.0, 1.5 mL) of NaCl 0.9%. The study was performed on 2 days with a 1-week washout period between the study days. On each study day the subjects received four injections in each thigh. To evaluate the validity of our pain assessing model the subjects received eight injections of 0.5% mL on one of the study days. Pain assessment was done immediately after each injection using both a 10-cm visual analog scale (VAS) and a six-item verbal rating scale (VRS). RESULTS: A significant difference in pain score on both the VAS (p < 0.05) and the VRS (p < 0.01) was seen between the four injection volumes. The pain was significantly increased with volumes of 1.0 and 1.5 mL. No significant difference in injection pain could be detected between 0.2 and 0.5 mL and between 1.0 and 1.5 mL. No significant period or carryover effect could be detected in the study. A significant correlation between the pain score on the VAS and the pain score on the VRS was found (r = 0.79, p < 0.0001). CONCLUSIONS: The pain of a subcutaneous injection is related to injection volume in the thigh. The results show that increasing the volume from 0.5 to 1.0 mL increases the pain significantly. The findings from this study should be considered when injection preparations for subcutaneous administration are formulated. The volume should generally be less than 1.0 mL if injected into the thigh.

Adult↗
PubMedDate not supplied

Improvement of patient convenience in treatment with growth hormone.

Patient compliance is of vital importance for the outcome of any medical therapy. Compliance is a problem especially in the treatment of non-life-threatening conditions, such as growth retardation in children, where motivation can be low and the rewards delayed. One way to improve compliance is through an improvement in patient convenience. As a result of these considerations as well as the positive experiences reported with insulin pen treatment, an injection pen for growth hormone administration (Nordiject) has been introduced. Results from several patient acceptance studies have shown that the injection pen and the preparation for use in the pen have been found effective and safe with good local tolerability and reduced perception of injection pain. The injection pen was found to simplify the injection procedure and was strongly preferred to conventional syringes and vials. Special attention has been paid to local discomfort and injection pain. A double-blind, randomized cross-over study has shown that 0.9% benzyl alcohol solvent causes statistically significantly less local discomfort that a 0.25% metacresol solvent when used for reconstitution of growth hormone. In another study the 30G needle was compared with 27G, and the use of the 30G needle seems also to give a reduction in injection pain. A further reduction in injection pain can be gained by improving the needle insertion technique. A randomized cross-over study compared two experimental devices, one with manual and one with automatic needle insertion. The results from this study showed a statistically significantly lower injection pain score for the automatic device compared to the manual. The above studies have shown that it is possible to improve patient convenience. Long-term studies will show whether this improvement results in improved compliance and hence a better treatment outcome.

Child↗