Growth response to rhIGF-I 80 microg/kg twice daily in children with growth hormone insensitivity syndrome: relationship to severity of clinical phenotype

BACKGROUND

rhIGF-I has been used effectively to promote growth in growth hormone insensitivity syndrome (GHIS) in doses ranging from 40 microg/kg twice daily to 150-200 microg/kg once daily. It appears that the dose of 80 microg/kg twice daily s.c. may induce an equivalent response to higher doses with less side-effects.

OBJECTIVE

To study the efficacy and safety of rhIGF-I, 80 microg/kg twice daily s.c., in children with GHIS and to analyse the relationship of growth response to severity of phenotype.

PATIENTS AND DESIGN

Eleven prepubertal children (3 females, 8 males) with GHIS; basal GH > 2.5 microg/l, IGF-I < 50 microg/l, IGFBP-3 < - 2SD; were treated with IGF-I 80 microg/kg twice daily in a multi-centre study. The baseline characteristics of these patients were as follows (mean +/- SD): age, 7.5 +/- 2.5 years (range, 2.5-11.7 years), bone age (Tanner-Whitehouse - 2 RUS), 5.2 +/- 2.4 years (range, 2.3-9.1 years), mean height SDS, - 5.6 +/- 1.6 (range, - 3.1 to - 8.1), height velocity (HV), 3.1 +/- 1.1 cm/year (range, 1.9-4.9 cm/year). Height, HV, weight, skinfold thickness, puberty stage and bone age were measured at baseline and 6 monthly for 2 years.

RESULTS

During the first 12 months of IGF-I therapy, the mean +/- SD HV was 7.7 +/- 1.6 cm/year (range, 6.1-11.2 cm/year), the mean +/- SD increase in HV was 4.7 +/- 2.1 cm/year (range, 1.7-8.8 cm/year) and the mean +/- SD progression of bone age was 1.9 +/- 1.0 years (range, 0.8-3.8 years). Pre-treatment height SDS at the start of IGF-I therapy correlated positively with pretreatment serum IGFBP-3 SDS levels (r = 0.85; P < 0.01). There was a significant inverse correlation between gain in height SDS and pre-treatment height SDS (r = - 0.76; P < 0.01). During the 2nd 12 months of therapy, mean HV was 7.0 +/- 3.4 cm/year (range 3.8-12.4) change in height SDS from 12 to 24 months was not significantly correlated with pre-treatment height SDS. Subscapular skinfold SDS decreased significantly (P < 0.05) during the study period, whereas there was no significant change in body mass index and triceps skinfold thickness SDS. Adverse events reported in the patient group included headache (2 patients), hypoglycaemia (2 patients), papilloedema (transient, 1 patient), lipohypertrophy (5 patients) and tonsillectomy/adenoidectomy (2 patients).

CONCLUSION

This study reveals that IGF-I treatment at a dose of 80 microg/kg twice daily is effective in patients with growth hormone insensitivity syndrome. During the first 12 months of therapy, there was a significant inverse relationship between growth response to IGF-I therapy and the severity of the phenotype of growth hormone insensitivity syndrome, as measured by height SDS, at the start of therapy. Patients with a more severe clinical phenotype of growth hormone insensitivity syndrome, who also had most severe IGFBP-3 deficiency, responded better than those who were more mildly affected. An analogous situation has been shown to be the case in GH-deficient patients treated with hGH.

The broad spectrum of inherited growth hormone insensitivity syndrome

Growth hormone (GH) insensitivity syndrome (GHIS) results in severe short stature and metabolic disturbances, but when this disorder is studied in more detail it is clear that there is marked clinical and biochemical heterogeneity. Many genetic defects of the GH receptor have been reported in inherited GHIS, but it now seems likely that some cases might be the result of defects of other genes or of links in the post-receptor cascade.

Effects of dietary taurine on auditory function in full-term infants

Three groups of neonates fed taurine supplemented infant formula, non-supplemented infant formula or breast milk, respectively, were studied from birth to 12 weeks of age. In addition to the measurement of whole blood taurine content, auditory function was monitored using auditory brainstem responses (ABRs) and transient evoked otoacoustic emissions (TEOAEs). The results showed a significant reduction in whole blood taurine concentration in the non-supplemented formula group. In addition, there was a significant drop in whole blood taurine levels in all 3 groups over the first four weeks of life. ABR wave latencies were significantly shorter in the non-supplemented group, with wave V showing the greatest reductions. Falling taurine levels after full-term birth may aid synaptic maturation/efficiency within the auditory system. TEOAE responses were significantly larger over the low to mid frequencies in the breast fed group suggesting improved middle ear function.

Regulation of transcription of the TATA-less human complement component C4 gene

The 5'-sequences flanking the human complement component C4 genes (C4A and C4B) have been analyzed for their ability to direct expression of a reporter gene in cell lines that constitutively express or do not express C4. No difference in the level of reporter gene expression was detected in cells transfected with C4A- or C4B-specific constructs. A series of reporter constructs containing progressively truncated C4 promoter fragments transfected into the hepatocyte Hep G2 cell line, identified the sequence contained within the region -178 to -39 as that associated with maximal reporter gene expression. This region contains consensus binding motifs for nuclear factor 1 (-110 to -97), Sp1 (-57 to -49), and three basic helix-loop-helix (-137 to -132, -98 to -93, and -78 to -73)-like transcription factors. Electromobility shift assays and DNase I footprinting analysis showed specific DNA-protein interactions of the C4 promoter at the nuclear factor 1, two E box (-98 to -93 and -78 to -73), and Sp1 binding domains. Site-directed mutagenesis of the Sp1 binding site resulted in total abrogation of reporter gene expression and mutation of the E box (-78 to -73) resulted in a 8-fold reduction in expression. We conclude that the Sp1 binding site at position -57 to -49 is critical for accurately initiated, basal transcription of C4.

Early onset of diabetic nephropathy

A 12 year old Asian girl with a four year history of poorly controlled insulin dependent diabetes mellitus developed overt diabetic nephropathy. There were no clinical features of Rabson-Mendenhall syndrome. Screening for microalbuminuria would have identified incipient diabetic nephropathy and highlighted the importance of good glycaemic control. Although screening for microalbuminuria is recommended after five years from diagnosis, it may be appropriate to undertake this annually in those with poor glycaemic control.

Elevated gamma-aminobutyric acid, glutamate, and vascular endothelial growth factor levels in the vitreous of patients with proliferative diabetic retinopathy

OBJECTIVE

To examine the relative levels of gamma-aminobutyric acid (GABA), glutamate, and vascular endothelial growth factor (VEGF) in the vitreous of nondiabetic and diabetic patients.

METHODS

Undiluted vitreous samples were obtained from 22 patients with proliferative diabetic retinopathy (PDR) and 28 patients without diabetes who underwent pars plana vitrectomy. Simultaneous venous blood samples also were obtained. Amino acid concentrations were determined using sensitive high-performance liquid chromatography, and VEGF levels by quantitative enzyme-linked immunosorbent assay. Hemoglobin concentrations in the blood and vitreous were determined using spectrophotometry.

RESULTS

The level of GABA in the vitreous of patients with PDR, 29.4 +/- 7.8 mumol/L, was significantly higher than in controls (18.4 +/- 5.5 mumol/L) (P = .004). The vitreous concentration of glutamate was higher in patients with PDR (24.7 +/- 14.0 mumol/L) compared with controls (9.1 +/- 5.1 mumol/L) (P < .001). Vitreous VEGF level was significantly higher in patients with PDR (1759 +/- 1721 pg/mL) compared with controls (27 +/- 65 pg/mL) (P < .001). There were moderately strong correlations between GABA and VEGF levels (r = 0.68) and glutamate and VEGF levels (r = 0.43). Elevated GABA, glutamate, and VEGF levels also correlated strongly with the presence of PDR. Correcting for possible introduction of these molecules by vitreous hemorrhage did not significantly alter these findings.

CONCLUSIONS

Levels of glutamate potentially toxic to retinal ganglion cells are found in the vitreous of patients with PDR. Elevated vitreous GABA may reflect amacrine cell dysfunction and underlie electroretinographic oscillatory potential abnormalities seen in diabetic retinopathy. The correlations of glutamate and GABA levels with an elevated VEGF level provide biochemical support for ischemia-induced neovascularization in patients with PDR. These findings present opportunities for novel therapeutic modalities in the treatment of PDR.

Evidence for early supply independent mitochondrial dysfunction in patients developing multiple organ failure after trauma

OBJECTIVE

To determine whether early supply independent mitochondrial oxidative dysfunction occurs in trauma patients who develop multiple organ failure (MOF).

DESIGN

Prospective focused observational trial.

METHODS

High-risk patients were aggressively resuscitated while being continuously monitored by near infrared spectroscopy. Near infrared spectroscopy monitoring strips allow for a direct comparison of changes in tissue oxyhemoglobin levels (HbO2), which reflect local oxygen supply, and cytochrome a,a3 redox, which reflects mitochondrial oxygen consumption. Under normal conditions, HbO2 and a,a3 redox are tightly coupled. On the other hand, decoupled HbO2 and a,a3 redox is a sign of mitochondrial oxidative dysfunction. Outcomes included MOF, oxygen delivery, oxygen consumption, lactate, and the presence of decoupled HbO2 and a,a3 redox.

RESULTS

Twenty-four high-risk patients were studied; nine (38%) developed MOF. At 12 hours of resuscitation, MOF and non-MOF patients did not have statistically different oxygen delivery and oxygen consumption, but lactate levels were significantly higher in MOF patients. Additionally, HBO2 and a,a3 redox were decoupled in eight (89%) MOF patients compared with two (13%) non-MOF patients (p < 0.05).

CONCLUSION

Severely injured trauma patients who develop MOF preferentially display evidence of mitochondrial oxidative dysfunction early in the course of their resuscitation despite early goal-oriented maximization of oxygen delivery.

Nocturnal enuresis: a placebo controlled trial of two antidepressant drugs

A multicentre, randomised, double blind treatment trial was set up comparing imipramine (a tricyclic antidepressant with anticholinergic action), mianserin (a quadricyclic antidepressant without anticholinergic activity), and placebo, (a) possibly to identify an effective alternative drug and (b) to elucidate the action of imipramine in enuretic children. Eighty children (65 boys, 15 girls) aged 5-13 years, wet three or more nights a week, were studied. Exclusions were a urinary tract infection or abnormality, other organic illness, or severe emotional disorders. After a four week assessment, 25 children were randomised to eight weeks' treatment with imipramine 25 mg, 26 to mianserin 10 mg and 29 to placebo, followed by four weeks without treatment. Dry nights and a wetness score were recorded throughout. During treatment, imipramine was superior to both placebo and mianserin (p < 0.001) in achieving dry nights and reducing wetness scores. It led to a definite improvement in 72% of children. Mianserin produced a mildly beneficial effect that was not superior to placebo. No side effects were recorded. Mianserin would not be a satisfactory alternative treatment for nocturnal enuresis. The efficacy of imipramine is unlikely to be the result of its antidepressant activity.

Variations in perceptions of child neglect

This study explored the perceptions of the seriousness of specific components of neglect held by mothers from three cultural groups and held by public child welfare workers in two different roles in the Chicago area. It then compared the perceptions of the mothers to those of the workers. The findings suggest that members of minority groups perceive some types of child neglect as more serious than do their Caucasian counterparts, that investigative workers see most types of child neglect as more serious than do service workers, and that workers see all types of child neglect as less serious than do the mothers. Comparisons revealed that various groups perceive the dimensions of neglect differently in terms of their potential harm to the child.

The last chance for learning disability nurses

I can well remember the sapiential advice offered to me by a knowing but disillusioned charge nurse some 20 years ago when I was about to commence my training to become a registered nurse for the mentally subnormal. ‘Don't bother son, the branch has no future’ were the words of encouragement that I was offered at the time. The Briggs Report (Department of Health and Social Security (DHSS), 1972) had recently been published and a question mark existed over the future of the branch. At that time 56000 individuals with learning disabilities lived in hospitals, some in conditions not dissimilar to those that we now see when pictures from eastern Europe are shown on our television screens.

Isokinetic trunk testing and employment

Isokinetic trunk testing is often performed to evaluate ability to perform job tasks. The purpose of this study was to evaluate the effectiveness of isokinetic trunk testing in identifying people with limited functional lifting capability and likely future injury potential. Two hundred thirty work applicants for heavy labor in a steel mill underwent job-related lifting ability and isokinetic trunk evaluation. There was no difference between the isokinetic scores of women who did not meet the job lifting criteria and those who did meet the lifting criteria. There was no difference between the isokinetic scores of workers who experienced occupational low back injury and those workers who did not over almost a 6-year follow-up period. In this study isokinetic trunk evaluation was of no value in employee selection.

Carnitine deficiency associated with long-term pivampicillin treatment: the effect of a replacement therapy regime

A 51 year old female developed a skeletal muscle myopathy after 3 months of pivampicillin therapy. Pivampicillin can cause carnitine deficiency due to the pivalic acid side group. Plasma carnitine content and the patients symptoms failed to improve significantly on discontinuing the drug. Oral carnitine replacement therapy was administered for 6 weeks but the patient's plasma carnitine levels responded only slowly to this treatment. It is suggested that pivampicillin inhibits uptake of carnitine from the gut and may either directly or indirectly depress endogenous carnitine synthesis. In such cases a more aggressive carnitine replacement regime is indicated and pivampicillin should be avoided in patients requiring long-term antibiotic administration.

An electromyographic analysis of two techniques for squat lifting and lowering

The purpose of this study was to examine the effects of two different alignments of the pelvis and three different loads on electromyographic (EMG) activity of the erector spinae and oblique abdominal muscles during squat lifting and lowering. Each of 15 healthy subjects lifted and lowered loads with the pelvis aligned both in an anterior tilt and in a posterior tilt. Based on total duration, both the lift and the lower were divided into two equal phases. The EMG activity of each muscle was quantified for each half of both the lift and the lower and was normalized to the total EMG produced by the muscle during a maximal voluntary isometric contraction. The results indicate (1) that the EMG activity of the erector spinae muscles was greater when subjects maintained an anterior tilt than when they maintained a posterior tilt; (2) that the EMG activity of the oblique abdominal muscles was greater in the first half of the lift than in the second half for both lifting styles, although the opposite was true for both lowering styles; and (3) that the EMG activity increased with increasing loads. The results suggest that the greater trunk muscle activity occurring with the anterior tilt position may ensure optimal muscular support for the spine while handling loads, thereby reducing the risk for low back injury.

Reliability of isokinetic measurements of trunk muscle performance

The purpose of this investigation was to assess the reliability of isokinetic trunk muscle performance. Sixty-one volunteers participated (29 men, 32 women; age range, 20-60 years). All subjects were without low-back symptoms at the time of testing. All testing was performed with the subject initially standing, using speeds of 60, 120, and 180 degrees per second. Ten repetitions of flexion and extension were performed reciprocally at each speed, with a 3-minute rest period between speeds. Test-retest intervals were 1 and 3 weeks from the initial test. Peak torque-to-body-weight ratios, extension-to-flexion ratios, and average work per repetition were calculated for each speed for flexion and extension. Data were analyzed with analysis of variance, intraclass correlation coefficients, and Pearson correlation coefficients. Intraclass correlation coefficient values ranged from .74 to .88 for measurements derived from peak torque, and from .88-.93 for measurements derived from work (with the exception of .69 for men at 180 degrees/sec). Standard error of measurements ranged from 8 to 32 ft-lb, with a tendency to increase with increasing speeds. It was concluded that, when using this protocol, isokinetic measurements of muscle function offer the clinician sensitive and reliable measurements of trunk muscle performance and that incorporating increased practice with women and longer rest periods with men may further decrease error associated with these isokinetic trunk strength measurements.

A novel DNA joining activity catalyzed by T4 DNA ligase

The use of T4 and E. coli DNA ligases in genetic engineering technology is usually associated with nick-closing activity in double stranded DNA or ligation of 'sticky-ends' to produce recombinant DNA molecules. We describe in this communication the ability of T4 DNA ligase to catalyze intramolecular loop formation between annealed oligodeoxyribonucleotides wherein Watson-Crick base pairing is absent on one side of the ligation site. Enzyme concentration, loop size, substrate specificity, and base composition were explored in an effort to maximize yield. Amounts of T4 DNA ligase in large molar excess to DNA template and ligated product are necessary to achieve high yields.

Argon laser photoablation of a choroidal osteoma

Choroidal osteomas are rare, juxtapapillary choroidal tumors, which are usually unilateral but can be bilateral in as many as 30% of patients. Choroidal neovascularization may complicate this condition and be associated with severe visual loss. A patient treated with argon laser photocoagulation for SRNVM is described, and clinical and radiographic evidence of destruction of the osteoma during an 8-year follow-up is presented. The possible mechanisms of laser's ablative effect on bone, in addition to clinical application for choroidal osteoma treatment, are discussed.

Strabismus caused by melanoma metastatic to an extraocular muscle

Nonocular melanoma rarely metastasizes to the orbit. We report the case of a melanoma presumably arising from an axillary lymph node sinus that metastasized to the left medial rectus muscle causing proptosis, diplopia, and reduced saccadic velocity measurements. Clinical, radiographic, and histopathologic data are presented and discussed.

Life threatening Branhamella catarrhalis pneumonia in young infants

Branhamella catarrhalis is a common nasopharyngeal commensal organism but is also a recognised pathogen. Lower respiratory tract infections caused by this organism have been reported in adults but not, to our knowledge, in otherwise healthy infants. Two infants, born prematurely, suffered near fatal pneumonia. Branhamella catarrhalis was the only microbial pathogen isolated in each case. We suggest that initial antibiotic therapy for severe pneumonia in young infants should be tailored to cover B. catarrhalis infection.

Short-pulse pumping of a recombination Balmer-alpha laser of hydrogenic sodium

A NaF foil target was irradiated at an intensity of 6.0 x 10(14) W/cm(2) with a 28-psec, 526-nm, 23-J laser pulse. A space- and time-averaged gain coefficient of 4 +/- 1 cm(-1) was obtained for Na XI H-alpha at 5.42 nm. Computer simulation gives a peak time- and space-resolved gain of ~18 cm(-1).

Patterns of hip rotation range of motion: a comparison between healthy subjects and patients with low back pain

The purpose of this study was to characterize and classify the prevalence of passive hip rotation range-of-motion (ROM) asymmetry in healthy subjects (n = 100) and in patients with low back dysfunction (n = 50). We categorized the subjects of both groups as having one of three patterns of hip rotation. Pattern IA existed when all ROM measurements were equal (within 10 degrees). Pattern IB existed when total medial and lateral rotation were equal, but one or more of the individual measurements were unequal. Pattern II existed when total medial rotation ROM was greater than total lateral rotation ROM. Those subjects with total lateral rotation ROM greater than total medial rotation ROM demonstrated pattern III. The distribution of subjects among the ROM pattern categories was significantly different in the patient and healthy subject groups. The frequency of occurrence of pattern III was greater in the patient group than in the healthy subject group. These results suggest an association between hip rotation ROM imbalance and the presence of low back pain.

Association between direction of lateral lumbar shift, movement tests, and side of symptoms in patients with low back pain syndrome

The purpose of this study was to determine the relationship between direction of lateral lumbar shift (LLS) and 1) the occurrence of symptoms during the side-bending movement test and 2) the location of symptoms in patients with low back pain syndrome (LBS). Twenty-four patients with LBS (17 male, 7 female) with an observable LLS were studied. Side-bending movement tests were performed bilaterally, and the results were recorded as positive if symptoms occurred during the movement. The location of symptoms (right side or left side) was obtained from the patient history. Use of the chi-square statistic revealed a statistically significant relationship between the direction of the LLS and the direction of the positive side-bending movement test. Seventeen tests (71%) were positive to the contralateral side of the LLS, and 5 (21%) were positive to the ipsilateral side. Two tests (8%) were negative in both directions. There was no significant relationship between the side of symptoms and the direction of the LLS. The determination of presence and direction of an LLS is necessary in certain physical therapy management approaches. Pain or restricted side-bending movement has been used to confirm the presence of an LLS. This study confirms the clinical usefulness of the side-bending movement test for determining the presence and direction of an LLS.

Type II fiber activation with electrical stimulation: a preliminary report

Electrical stimulation to augment or maintain muscle performance has been well documented. The purpose of this preliminary report is to present the results of a single-case study conducted to determine the order of activation of skeletal muscle fibers as a result of electrical stimulation. The subject's quadriceps femoris muscles were electrically stimulated at 80% of maximal isometric torque. Pre-stimulation and immediate post-stimulation muscle biopsy samples were obtained, and a modification of the glucogen-depletion method was used to determine activation of muscle fibers. The pre-stimulation muscle biopsy sample demonstrated uniform periodic acid-Schiff (PAS)-positive staining in all fiber types, whereas the post-stimulation muscle biopsy sample showed glycogen depletion of type II muscle fibers. The most PAS-negative muscle fibers were type IIa skeletal muscle fibers. The results of this single-case study provide evidence that electrical stimulation, as described, selectively activates type II skeletal muscle fibers. The implication of this finding is that, in many chronic diseases, type II fibers are selectively and preferentially affected. Electrical stimulation may be a clinically viable technique to use in patients with type II fiber involvement.

On developing expert-based decision-support systems in physical therapy: the NIOSH low back atlas

We have described the process of the initial development of an expert-based decision-support system for the management of patients with low back syndrome. Important considerations for developing decision-support systems are reviewed, both generally and specifically. The term "expert" is dissected and discussed. Our work so far involved congregation of a number of experts and compilation of a testing protocol. We are now refining the system for specific populations and purposes.

Total contact casting in treatment of diabetic plantar ulcers. Controlled clinical trial

This study compared the treatment of total contact casting (TCC) with traditional dressing treatment (TDT) in the management of diabetic plantar ulcers. Forty patients with diabetes mellitus and a plantar ulcer but with no gross infection, osteomyelitis, or gangrene were randomly assigned to the TCC group (n = 21) or TDT group (n = 19). Age, sex, ratio of insulin-dependent diabetes mellitus to non-insulin-dependent diabetes mellitus, duration of diabetes mellitus, vascular status, size and duration of ulcer, and sensation were not significantly different between groups (P greater than .05). In the experimental group, TCC was applied on the initial visit, and subjects were instructed to limit ambulation to approximately 33% of their usual activity. Subjects in the control group were prescribed dressing changes and accommodative footwear and were instructed to avoid bearing weight on the involved extremity. Ulcers were considered healed if they showed complete skin closure with no drainage. Ulcers were considered not healed if they showed no decrease in size by 6 wk or if infection developed that required hospitalization. In the TCC group, 19 of 21 ulcers healed in 42 +/- 29 days; in the TDT group, 6 of 19 ulcers healed in 65 +/- 29 days. Significantly more ulcers healed (chi 2 = 12.4, P less than .05) and fewer infections developed (chi 2 = 4.1, P less than .05) in the TCC group. We conclude TCC is a successful method of treating diabetic plantar ulcers but requires careful application, close follow-up, and patient compliance with scheduled appointments to minimize complications.

Electrical stimulation of quadriceps femoris in an elite weight lifter: a single subject experiment

The response to treatment of high intensity neuromuscular electrical stimulation (NMES) to both quadriceps femoris muscles as an adjunct to ongoing weight training was evaluated using a single subject experimental design. For an elite weight lifter weekly maximal measurements of snatch (S), clean and jerk (CJ), and front squat (SQ) were obtained over 4 months during which the subject weight trained daily for 3 h. The 1st month, baseline data were collected. After baseline measurements, a 1-month period of high-intensity NMES was added to the subject's weight training. NMES was then withdrawn for 1 month and administered once more for 2 weeks. Three quadriceps femoris muscle biopsies were taken, two during the initial baseline period and one just before the end of the first stimulation period. The results showed a significant and clear relationship between performance gains and NMES administration and withdrawal. Steep gains for S, CJ, and SQ were seen after 2 weeks of stimulation, with front squat showing a 20-kg increase within the 1st week of both stimulation periods. Muscle biopsy showed an increased type I fiber area, decreased type IIa and IIb fiber area, and an increase of type II fibers after NMES. The results of this study support the use of high-dose NMES as an adjunct to weight training in elite lifters.

Argininosuccinic aciduria--an underdiagnosed cause of neonatal death?

We describe a case of neonatal argininosuccinic aciduria, a condition we suggest is underdiagnosed. Although the clinical presentation can be of overwhelming septicaemia, certain routine biochemical investigations are indicative of this inborn error of urea cycle metabolism.