Is obesity becoming a public health problem in India? Examine the shift from under- to overnutrition problems over time

This study aimed to examine the prevalence and trends of overweight, obesity and undernutrition in recent decades in India. Based on a systematic literature search on PubMed and other data sources, most published studies were regional or local surveys in urban areas, while good representative data from the India National Family Health Surveys (NFHS, 1992-1993, 1998-1999 and 2005-2006) allowed for examining the trends at the national level. Overall, the available data showed that in India, prevalence of overweight was low while that of undernutrition remained high. Overweight was more prevalent among female, urban and high-socioeconomic-status (SES) groups. NFHS data showed that the prevalence of overweight in women and pre-school children did not increase much in the last decade: 10.6% and 1.6% in 1998-1999 to 12.6% and 1.5% in 2005-2006 respectively. As for underweight, NFHS 2005-2006 showed high prevalence among ever-married women (about 35%) and pre-school children (about 42%). The prevalence of overweight and obesity had increased slightly over the past decade in India, but in some urban and high-SES groups it reached a relatively high level. Factors associated with undernutrition need closer examination, and prevention of obesity should be targeted at the high-risk groups simultaneously.

Synthesis and Characterization of Styrene-Butadiene Rubber-Clay Nanocomposites with Enhanced Mechanical and Gas Barrier Properties

Five styrene-butadiene rubber (SBR)/clay nanocomposite or hybrid systems were synthesized via mechanical mixing of SBR using a Brabender mixer and a 2-roll mill in the presence of unmodified sodium montmorillonite (Na-MMT) clay, MMT modified with octadecylamine (C18amine), MMT modified with a zwitterionic surfactant, octadecyldimethyl betaine (C18DMB), and MMT modified with a polymerizable cationic surfactant, vinylbenzyl octadecyldimethyl ammonium chloride (VODAC) or vinylbenzyl dodecyldimethyl ammonium chloride (VDAC). The surfactant chain length and functional groups affected the dispersion of clay nanolayers in the matrix and the overall properties of the nanocomposites. X-ray diffraction (XRD) revealed peaks corresponding to intercalated structures; transmission electron microscopy (TEM) observations agreed well with XRD assessment of the composites. SBR/VODAC-MMT system exhibited the best dispersion among the nanocomposites studied. VODAC-MMT was partially exfoliated in SBR matrix and the average aspect ratio of the nanolayer stacks or aggregates was high (20). Depending on the amount of clay, considerable mechanical reinforcement and gas barrier enhancement were achieved in nanocomposites over pure rubber. Tensile strength in excess of 18MPa was observed in SBR nanocomposites with 30 phr C18 organoclays. The storage modulus at 25C increased by a factor of four by incorporating 10 phr VODAC-MMT in SBR. The most pronounced oxygen barrier enhancement was again observed in SBR/VODAC-MMT nanocomposite with the reduction of permeability by 60% at silicate volume fraction of 0.06. The superior performance of nanocomposites containing VODAC-MMT is attributed to the presence of the vinyl-benzyl group and 18 carbon-atom tail in the surfactant leading to high compatibility with SBR and nano-scale dispersion in the SBR matrix.

Outcome of a conservative policy for managing acute sigmoid diverticulitis

Background

A conservative policy for patients presenting with acute sigmoid diverticulitis is associated with a low operation rate, and low overall and operative mortality rates. The long-term consequences of such a policy were investigated.

Methods

Data were collected prospectively for 232 patients with acute sigmoid diverticulitis between 1990 and 2004. Details of all subsequent readmissions were obtained and survival to August 2005 was analysed.

Results

Of the 232 patients admitted, 60 (25·9 per cent) were known to have diverticulosis; in 172 patients it was a new diagnosis. Thirty-eight patients (16·4 per cent) underwent sigmoid resection, with one death. Three elderly patients in whom a decision was made not to operate had perforated diverticulitis at autopsy. Of 191 patients discharged without resection, 35 (18·3 per cent) subsequently underwent sigmoid resection: 26 (13·6 per cent) elective and nine (4·7 per cent) emergency, with one death.

Conclusion

A conservative policy is safe in both the short term and the long term.

Endoscopic trans-anal resection of rectal tumours: critical appraisal of an interdisciplinary approach

OBJECTIVE

Endoscopic trans-anal resection (ETAR) is an accepted technique for treating benign rectal adenomas that relies on technical expertise with the urological resectoscope. We present our experience with ETAR in an interdisciplinary setting combining the decision-making of the colorectal surgeon with the technical skill of the urologist.

METHOD

Assessment of all patients with adenomas and their subsequent care was organized by the colorectal team. Those with carpet-like rectal adenomas were referred to the urologist for ETAR performed using a Storz-Olympus 27/28Ch resectoscope, with roller-ball for haemostasis and glycine for irrigation.

RESULTS

Twenty-four patients (43-93 years, median 71 years; 14 men and 10 women) underwent 51 ETAR procedures from 1999 to 2005, with a median of two (range 1-6) procedures per patient. Complete clearance was achieved on 25 occasions. Two intra-operative extra-peritoneal perforations occurred which were managed conservatively. There were four cases of postoperative haemorrhage, two of which required a repeat procedure to secure haemostasis. Four patients had postoperative pyrexia that settled with oral antibiotics. Mean tumour distance from the anal verge was 7 cm (range 2-12 cm); the mean tumour area was 8 cm(2) (range 3-20 cm(2)); the mean operating time was 34 min (range 15-60 min) and the mean hospital stay was 32 h (range 24-120 h).

CONCLUSION

An interdisciplinary approach to ETAR uses available clinical resources efficiently as the colorectal surgeon does need to acquire the technical skills of endoscopic resection. Our results compare favourably with other published series and this approach can be adopted by any centre where colorectal and urological surgeons work together.

Sleep duration and its correlates in a sample of Saudi elementary school children

INTRODUCTION

This study was conducted to estimate sleep duration in Saudi elementary school children, sleep habits and practices that may affect it, and compare our results to published data in other societies.

METHODS

Parents of elementary school children were surveyed regarding their children's bedtime, rise time, sleep duration at night and daytime nap duration during weekdays and weekends. A questionnaire inquiring about demographical data, specific sleep problems and habits, and home environment was completed by the parents.

RESULTS

The study comprised 511 (50.5 percent) boys and 501 (49.5 percent) girls. During weekdays, bedtime for the whole group was 21.3 +/- 1.8 hours, rise time was 5.9 +/- 0.5 hours, total sleep time (TST) was 8.4 +/- 1.1 hours, and TST and nap was 9.98 +/- 1.3 hours. Multivariate analysis revealed that TST was affected by regularity of bedtime, mother's level of education, daytime naps, and the habits of watching television (TV) and playing computer games after 20.00 hours.

CONCLUSION

Nighttime sleep duration is shorter in Saudi school children compared to published data. Several factors appeared to affect sleep duration, including mother's educational level, daytime naps and watching TV at night.

Mechanical devices for urinary incontinence in women

BACKGROUND

Incontinence can have a devastating effect on the lives of sufferers with significant economic implications. Non-surgical treatments such as pelvic floor muscle training and the use of mechanical devices are usually the first line of management. The latter more so when a person did not want surgery or when considered unfit for surgery. Mechanical devices are inexpensive and do not compromise future surgical treatment.

OBJECTIVES

To determine the effects of mechanical devices in the management of adult female urinary incontinence.

SEARCH STRATEGY

We searched the Cochrane Incontinence Group Specialised Trials Register (7 December 2005). The register contains trials identified from MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL and handsearching of journals and conference proceedings.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials of mechanical devices in the management of adult female urinary incontinence determined either by symptom classification or by urodynamic diagnosis.

DATA COLLECTION AND ANALYSIS

Three reviewers assessed the identified studies for eligibility and methodological quality and independently extracted data from the included studies. Data analysis was performed using RevMan software (version 4.2).

MAIN RESULTS

There were six trials involving a total of 286 women. Two small trials compared a mechanical device with no treatment and although they suggested that use of a mechanical device might be better than no treatment, the evidence for this was inconclusive. Five trials compared one mechanical device with another. Quantitative synthesis of data from these trials was not possible because different mechanical devices were compared in each trial using different outcome measures. Data from the individual trials showed no clear difference between devices, but with wide confidence intervals. There were no trials comparing a mechanical device with another type of treatment.

AUTHORS' CONCLUSIONS

The place of mechanical devices in the management of urinary incontinence remains in question. Currently there is little evidence from controlled trials on which to judge whether their use is better than no treatment and a large well-conducted trial is required for clarification. There was also insufficient evidence in favour of one device over another and no evidence to compare mechanical devices with other forms of treatment.

Mechanical devices for urinary incontinence in women

BACKGROUND

Incontinence can have a devastating effect on the lives of sufferers with significant economic implications. Non-surgical treatments such as pelvic floor muscle training and the use of mechanical devices are usually the first line of management. The latter more so when a person did not want surgery or when considered unfit for surgery. Mechanical devices are inexpensive and do not compromise future surgical treatment.

OBJECTIVES

To determine the effects of mechanical devices in the management of adult female urinary incontinence.

SEARCH STRATEGY

We searched the Cochrane Incontinence Group Specialised Trials Register (7 December 2005). The register contains trials identified from MEDLINE, the Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL and handsearching of journals and conference proceedings.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials of mechanical devices in the management of adult female urinary incontinence determined either by symptom classification or by urodynamic diagnosis.

DATA COLLECTION AND ANALYSIS

Three reviewers assessed the identified studies for eligibility and methodological quality and independently extracted data from the included studies. Data analysis was performed using RevMan software (version 4.2).

MAIN RESULTS

There were six trials involving a total of 286 women. Two small trials compared a mechanical device with no treatment and although they suggested that use of a mechanical device might be better than no treatment, the evidence for this was inconclusive. Five trials compared one mechanical device with another. Quantitative synthesis of data from these trials was not possible because different mechanical devices were compared in each trial using different outcome measures. Data from the individual trials showed no clear difference between devices, but with wide confidence intervals. There were no trials comparing a mechanical device with another type of treatment.

AUTHORS' CONCLUSIONS

The place of mechanical devices in the management of urinary incontinence remains in question. Currently there is little evidence from controlled trials on which to judge whether their use is better than no treatment and a large well-conducted trial is required for clarification. There was also insufficient evidence in favour of one device over another and no evidence to compare mechanical devices with other forms of treatment.

Cell viability effects of triamcinolone acetonide and preservative vehicle formulations

AIM

To assess the effect of triamcinolone acetonide and preservative vehicle formulations on human retinal pigment epithelium (ARPE19) cells over a range of concentrations.

METHODS

Triamcinolone acetonide, in its trade and preservative free formulations, along with the preservative vehicle were added to ARPE19 cell cultures in various concentrations (0.01-1.0 mg/ml). Cell viability was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay at day 5 after exposure. Functionality of the cultured ARPE19 cell line was confirmed by exposure to a previously characterised toxic agent, tamoxifen.

RESULTS

The ARPE19 cell line behaved as predicted with exposure to tamoxifen. All formulations caused significant reductions in ARPE19 cell viability at the highest concentrations (1.0 mg/ml for triamcinolone preparations and undiluted vehicle). Cell viability was reduced to the greatest degree in trade formulation triamcinolone, less so by the vehicle, and least by preservative free triamcinolone. At lower concentrations no significant effect on cell viability was observed, although cell viability was found to be inversely proportional to increasing concentration of all tested reagents

CONCLUSIONS

Both the trade and preservative free formulations of triamcinolone acetonide as well as the vehicle result in cell loss at in vitro concentrations of 1 mg/ml. Although this represents theoretical vitreous concentrations achieved with current widespread therapeutic use it probably does not indicate the actual exposure of cells in their biological milieu. That cell viability was reduced most in the trade formulation suggests a possible potentiated inhibitory toxic effect of triamcinolone acetonide and vehicle at higher concentrations.

Antioxidant vitamins E and C as adjunct therapy of severe acute lower-respiratory infection in infants and young children: a randomized controlled trial

OBJECTIVE

To evaluate the effect of antioxidant Vitamins E and C as adjunct therapy of severe acute lower respiratory infection (ALRI) in children.

DESIGN

Randomized double-blind placebo-controlled clinical trial.

SETTING

A large childrens' hospital serving the urban poor in Kolkata, India.

SUBJECTS

Children aged 2-35 months admitted with severe ALRI.

INTERVENTION

In total, 174 children were randomly assigned to receive alpha-tocopherol 200 mg and ascorbic acid 100 mg twice daily or placebo for 5 days. All children received standard treatment for severe ALRI. Outcome measures were: time taken to recover from a very ill status, fever, tachypnoea, and feeding difficulty; and improvement in oxidative stress and immune response indicated by thiobarbituric acid reacting substances (TBARS) and response to skin antigens, respectively.

RESULTS

Recovery rate ratios (95% CI) using proportional hazards model were 0.89 (0.64-1.25), 1.01 (0.72-1.41), 0.86 (0.57-1.29), and 1.12 (0.77-1.64) for very ill status, feeding difficulty, fever, and tachypnoea, respectively. TBARS values were high and similar in the two groups at admission, discharge, and at 2 weeks follow-up. Serum alpha-tocopherol significantly increased in treated group at discharge. Immune response to skin antigens were very poor at admission and after 2 weeks, in both groups.

CONCLUSION

Infants with severe ALRI failed to benefit from two antioxidant nutrients as adjunct therapy. Severe ALRI in infants may cause cell-mediated immune dysfunction. We need a better understanding of oxidative processes in growing infants to help us better design interventions with antioxidant therapy.

Brain-derived neurotrophic factor variants are associated with childhood-onset mood disorder: confirmation in a Hungarian sample

Brain-derived neurotrophic factor (BDNF) is a nerve growth factor that has been implicated in the neurobiology of depression. Our group has previously reported an association between a BDNF variant and childhood-onset mood disorder (COMD) in an adult sample from Pittsburgh. We hypothesize that variants at the BDNF locus are associated with COMD. Six BDNF polymorphisms were genotyped in 258 trios having juvenile probands with childhood-onset DSM-IV major depressive or dysthymic disorder. BDNF markers included the (GT)n microsatellite, Val66Met and four other single-nucleotide polymorphisms (SNPs) distributed across the BDNF gene. Family-based association and evolutionary haplotype analysis methods were used. Analysis of linkage disequilibrium (LD) revealed substantial LD among all six polymorphisms. Analyses of the Val66Met polymorphism demonstrated significant overtransmission of the val allele (chi2=7.12, d.f.=1, P=0.0076). Consistent with the pattern of LD, all other SNPs showed significant biased transmission. The (GT)n microsatellite alleles also indicated a trend towards biased transmission (170 bp: Z=2.095, P=0.036). Significant haplotypes involved Val66Met and BDNF2 (P=0.0029). In this Hungarian sample, we found all five BDNF SNPs tested and a haplotype containing the BDNF Val66Met Val allele to be associated with COMD. These results provide evidence that BDNF variants affect liability to juvenile-onset mood disorders, supported by data from two independent samples.

Amniotic IGF-I supplementation of growth-restricted fetal sheep alters IGF-I and IGF receptor type 1 mRNA and protein levels in placental and fetal tissues

We have previously reported that chronic intra-amniotic supplementation of the late gestation growth-restricted (IUGR) ovine fetus with IGF-I (20 microg/day) increased gut growth but reduced liver weight and circulating IGF-I concentrations. Here we report mRNA and protein levels of IGF-I, the type 1 IGF receptor (IGF-1R) and IGF-binding proteins (IGFBP)-1, -2 and -3 in fetal gut, liver, muscle and placenta from fetuses in that earlier study in an attempt to explain these contrasting results. mRNA and protein were extracted from tissues obtained at post mortem at 131 days of gestation (term, 145 days) from three groups of fetuses (control, IUGR+saline and IUGR+IGF-I, n=9 per group). Control fetuses were unembolised and untreated. In the IUGR groups, growth restriction was induced from 113 to 120 days by placental embolisation; from 120 to 130 days fetuses were treated with daily intra-amniotic injections of either saline or 20 microg IGF-I. mRNA was measured by RT-PCR or real-time RT-PCR, and protein by Western blot. In liver, muscle and placenta, IGF-I mRNA and protein levels were reduced by between 8 and 30% in IGF-I-treated fetuses compared with saline-treated fetuses and controls with no change in IGF-1R mRNA or protein levels. In contrast, in the gut, IGF-I mRNA and protein levels were not significantly altered with IGF-I treatment, but IGF-1R levels were increased, especially in the jejunum. Immunolocalisation demonstrated that IGF-1R expression was confined to the luminal aspect of the gut. mRNA levels of all three IGFBPs were reduced in the gut of IGF-I-treated fetuses, but hepatic expression was significantly increased. These data demonstrated tissue-specific regulation of IGF-I, IGF-1R and IGFBPs-1, -2 and -3 in response to intra-amniotic IGF-I supplementation, though the underlying mechanisms remain obscure.

Association study of brain-derived neurotrophic factor in adults with a history of childhood onset mood disorder

Brain-derived neurotrophic factor (BDNF) is a nerve growth factor that has antidepressant-like effects in animals. BDNF gene polymorphisms have been associated with bipolar disorder. We tested two genetic polymorphisms of BDNF for their association with childhood-onset mood disorders (COMD) within the context of a case-control design. Two BDNF polymorphisms, a dinucleotide repeat (GT)(n), and a single nucleotide polymorphism (SNP) in the coding region, val66met, were genotyped in 99 adults with a history of COMD and matched psychiatrically healthy controls. A genomic control (GC) method was used to evaluate population substructure. Alleles at (GT)(n) were highly associated with COMD in this sample (chi(2) = 17.8; d.f. = 5; P = 0.0032). The odds of carrying the 168 bp allele were 3.94 times greater for cases than controls (CI = 1.72-9.04). Alleles of val66met were not significantly associated with COMD. GC analysis suggested population substructure was not a confounder of association. Analysis of haplotypes, in which (GT)(n) was treated as a binary variable (long vs. short alleles), provided significant evidence that the haplotype val/short contributes to liability to COMD. The BDNF (GT)(n) marker and the val/short haplotype are associated with COMD in this sample, in accordance with the previously described neurotrophic hypothesis of depression and some previous studies of association for bipolar disorder and neuroticism.

Frequency of food items among households in a low socioeconomic area of Karachi

OBJECTIVE

To describe the frequency of certain food items among families in a low socioeconomic area of Karachi and their association with socioeconomic variables.

METHOD

A cross sectional survey of houses selected through random sampling using a pre-tested structured questionnaire.

RESULTS

A total of 294 houses were surveyed, 23% households consumed meat almost daily, 55% consumed vegetables almost daily.

CONCLUSION

The survey showed that the consumption of food items in our study population is less as compared to what is recommended.

Association study of serotonin-2A receptor gene polymorphism and panic disorder in patients from Canada and Germany

The T102C serotonin-2A (5-HT2A) receptor gene polymorphism has been studied extensively in a number of complex psychiatric conditions with mixed results. Recently a genetic association has been described between this polymorphism and panic disorder in a Japanese sample. To evaluate the impact of the T102C polymorphism in panic disorder we genotyped triad families (panic disorder patient and parents), and cases with controls in Canadian and German samples. No significant transmission disequilibrium was observed between the alleles of the T102C 5-HT2A receptor gene polymorphism and panic disorder, nor was a significant excess of either allele found in the case control analysis. Our data suggest thus that this polymorphism is unlikely to play a major role in the pathogenesis of panic disorder.

BDNF and COMT Polymorphisms: Relation to Memory Phenotypes in Young Adults With Childhood-Onset Mood Disorder

Recent investigations in several species have suggested a role for brain-derived neurotrophic factor (BDNF) in memory, which may be mediated by the influence of BDNF on neuronal plasticity in the hippocampus. BDNF polymorphisms have also been associated with mood disorders. Catechol-O-methyltransferase (COMT) metabolizes dopamine and has been implicated in prefrontal function, another area of the brain relevant for memory. In a sample of 63 young adults with a history of childhood-onset mood disorder, we typed three BDNF polymorphisms, including the BDNF Val66Met single nucleotide polymorphism (SNP), and the COMT Val108/158Met SNP. Multivariate analysis of variance was used to test the association between BDNF and COMT markers and measures of declarative memory. Variants at the three BDNF markers and one COMT marker were not associated with declarative memory function p-values ranged from 0.25 to 0.98. Higher IQ (F = 6.18, df = 4, 58, p = 0.0003) and female gender (F = 4.41, df = 4, 58, p = 0.0035) were associated with more optimal performance on the memory tasks. This study did not provide evidence supporting an association between BDNF and COMT genes and declarative memory phenotypes.

Postnatal development and testosterone dependence of a rat epididymal protein identified by neonatal tolerization

A rat epididymal protein of 27 kDa was identified using neonatal tolerization. This study reports the production and characterization of a polyclonal antiserum to this protein. ELISA was used to demonstrate that this antiserum reacts strongly with epididymal sperm proteins, but has little or no reactivity with testicular proteins. Western blot analysis revealed that this polyclonal antiserum recognized a 27 kDa protein extracted from the corpus epididymidis as well as from spermatozoa from the corpus and cauda epididymides, and immunostaining revealed the presence of the protein in the corpus to cauda epididymides. Stronger reactivity was observed in the supranuclear region and stereocilla of principal cells of the corpus epididymidis and in the luminal content of the corpus and cauda epididymides. The testicular section showed no reactivity. Treatment with the antiserum resulted in time- and dose-dependent agglutination of rat spermatozoa. By indirect immunofluorescence, the antiserum localized proteins in the mid-piece region of rat spermatozoa. Studies were carried out to determine the age at which the protein first became apparent during postnatal development. The protein was expressed from day 40 onwards, as demonstrated by western blot analysis. The androgen regulation of this protein was ascertained by castration and supplementation studies. Expression of this protein showed a decline starting at day 14 after castration and by day 21 the protein was absent; however, androgen replacement resulted in the reappearance of the protein. The results of these studies indicate that the protein identified is specific to the epididymis, and is regulated by development and androgens. The importance of epididymis-specific proteins that are regulated by androgens in sperm maturation is discussed, and the need to ascertain the sequence of the protein and clone the cognate gene is indicated.

Lean body mass in preschool aged urban children in India: gender difference

OBJECTIVE

To estimate lean body mass (LBM) in preschool aged boys and girls in India and explore gender difference.

DESIGN

Crossectional.

SETTING

Immunization clinic of a charitable Government General Hospital in Kolkata, India.

SUBJECTS

Two-hundred and forty-five children (147 boys and 98 girls) aged 1-5 y from among the urban poor were admitted in the study between July 1999 and December 2000. Children with acute or chronic illness or congenital malformation were excluded.

METHOD

Length/height to the nearest 0.1 cm, weight to the nearest 10 g and total body resistance using multifrequency bioelectrical (Xitron 4000B) impedance analyzer (BIA) at 50 kHz were measured. Their nutritional status was compared with National Center for Health Statistics (NCHS) median data and lean body mass (LBM) was calculated using anthropometry and BIA equations. The groups were compared using analysis of variance and multiple linear regression.

RESULTS

Girls were more stunted (P<0.001) and underweight (P<0.047), while the degree of wasting was similar. Mean LBM percentage was higher in boys compared with girls by anthropometry (P<0.001) and BIA (P<0.005), which persisted after adjusting for age. With increasing age, LBM percentage declined in girls (P<0.02) in contrast to reference girls, in whom it increased. In boys LBM percentage increased with age as is in reference boys.

CONCLUSIONS

In addition to the girls being more stunted and underweight, LBM% decreased in girls with increasing age but steadily increased in boys, suggesting hidden deprivation of female children.

Comparative efficacy and safety of remifentanil and fentanyl in 'fast track' coronary artery bypass graft surgery: a randomized, double-blind study

This multi-centre, parallel group, randomized, double-blind study compared the efficacy and safety of high-dose remifentanil administered by continuous infusion with an intermittent bolus fentanyl regimen, when given in combination with propofol for general anaesthesia in 321 patients undergoing elective coronary artery bypass graft surgery. A significantly lower proportion of the patients who received remifentanil had responses to maximal sternal spread (the primary efficacy endpoint) compared with those who received fentanyl (11% vs 52%; P<0.001). More patients who received remifentanil responded to tracheal intubation compared with those who received fentanyl (24% vs 9%; P<0.001). However, fewer patients who received remifentanil responded to sternal skin incision (11% vs 36%; P<0.001) and sternotomy (14% vs 60%; P <0.001). Median time to extubation was longer in the subjects who received remifentanil than for those who received fentanyl (5.1 vs 4.2 h; P=0.006). There were no statistically significant differences between the two groups in the times for transfer from intensive care unit or hospital discharge but time to extubation was significantly longer in the remifentanil group. Overall, the incidence of adverse events was similar but greater in the remifentanil group with respect to shivering (P<0.049) and hypertension (P<0.001). Significantly more drug-related adverse events were reported in the remifentanil group (P=0.016). There were no drug-related adverse cardiac outcomes and no deaths from cardiac causes before hospital discharge in either treatment group.

Diffuse unilateral hemorrhagic retinopathy associated with accidental perinatal strangulation. A clinicopathologic report

OBJECTIVE

To report an unusual case of diffuse retinal hemorrhage associated with strangulation in a neonate with a tightly wrapped nuchal cord around his neck at birth who was noted to have eyelid and subconjunctival petechial hemorrhages upon delivery.

METHODS

Clinical diagnostic examination as well as postmortem gross and histopathologic examination of ocular and central nervous system structures was performed.

RESULTS

Funduscopic and gross pathologic examination of the eyes revealed extensive unilateral retinal hemorrhage of the right eye only. This was corroborated by histopathologic studies, which revealed unilateral diffuse hemorrhage throughout all nuclear layers of the retina with a particularly dense nerve fiber layer and sub-internal limiting membrane hemorrhage in the macula along with extraocular muscle and episcleral hemorrhage. Clinical, gross, and microscopic examination also revealed multiple areas of hemorrhage involving the right side of the brain and throughout the cerebellum.

CONCLUSION

Although retinal findings in nonaccidental trauma are common, accidental strangulation retinopathy in neonates is a rare occurrence. To the authors' knowledge, this case is the only documented histopathologic study of hemorrhagic retinopathy associated with strangulation in the literature.

Growth inhibition and differentiation of C6 glioma cells on treatment with hmba

HMBA, a differentiation inducer belonging to the class of hybrid polar compounds, is known to induce terminal differentiation of a number of leukemic and solid tumour cell lines. In this report we have shown that HMBA markedly inhibits growth of C6 glioma cells at non-cytotoxic concentrations ranging from 2.5 m m to 10 m m in a dose-dependent manner. The growth inhibitory effect can be detected as early as 18--24 h. By the sixth day the growth inhibition decreases at all the concentrations tested. Treatment with HMBA results in an accumulation of C6 cells in G0/G1 phase along with a decrease in the number of cells in S phase. HMBA induces morphological differentiation of C6 cells and increases expression of glial fibriliary acidic protein (GFAP), a marker for mature astrocytes. HMBA induces c-fos and represses cycloheximide-induced c-jun and fra-1 expression. HMBA-induced growth inhibition of C6 cells is accompanied by a decrease in Cdk4 protein levels. However, HMBA fails to sustain low Cdk4 levels, which may be responsible for HMBA's failure to sustain the growth inhibitory effect.

IL-8 and MCP-1 secretion is enhanced by the peptide-nucleic acid immunomodulator, Product R, in U937 cells and primary human monocytes

Product R (Reticulose) is a peptide-nucleic acid immunomodulator recently shown to enhance the expression of mRNAs encoding pro-inflammatory cytokines. Interleukin 8 (IL-8) and macrophage chemoattractant protein-1 (MCP-1) are pro-inflammatory chemokines involved in immune cell mobilization and stimulation. To determine whether Product R acts by upregulating these chemokines, we assayed its effects on the expression of IL-8 and MCP-1 mRNAs and proteins by human monocytic U937 cells and by adherent peripheral blood mononuclear cells (PBMCs). U937 cells were cultured for 0-21 days in media containing 0-20% Product R or phosphate-buffered saline (PBS). Compared to control cultures, cells cultured in Product R expressed increased amounts of IL-8 and MCP-1 mRNAs, as measured by reverse transcriptase-polymerase chain reaction (RT-PCR). Product R also increased secretion of IL-8 and MCP-1, as measured by enzyme-linked immunosorbent assay (ELISA), and boosted secretion induced by bacterial lipopolysaccharide (LPS), in a time- and dose-dependent manner. In adherent PBMCs, Product R increased IL-8 and MCP-1 secretion, but reduced LPS-induced MCP-1 secretion. While mRNAs encoding the IL-8 receptor, CXCR2, and the MCP-1 receptor, CCR2, were increased in U937 cells cultured in 5-10% Product R, we observed no change in binding of receptor-specific antibodies. These findings suggest that Product R upregulates the expression of IL-8 and MCP-1, which may boost immune system activity in virally-infected patients.

Cysteine-rich and basic domain HIV-1 Tat peptides inhibit angiogenesis and induce endothelial cell apoptosis

Previous findings suggest that both the Tat polypeptide encoded by HIV-1 and Tat-derived peptides can induce angiogenesis via activation of the KDR receptor for Vascular Endothelial Growth Factor (VEGF). We identified 20 amino acids and 12 amino acid peptides corresponding to the cysteine-rich and basic domains of HIV-1 Tat which inhibited (125)I-VEGF(165) binding to KDR and neuropilin-1 (NP-1) receptors in endothelial cells. Cysteine-rich and basic Tat peptides inhibited VEGF-induced ERK activation and mitogenesis in endothelial cells, and inhibited angiogenesis in vitro at concentrations similar to those which inhibited VEGF receptor binding. These peptides also inhibited proliferation, angiogenesis, and ERK activation induced by basic fibroblast growth factor with similar potency and efficacy. Surprisingly, we found that both cysteine-rich and basic domain Tat peptides strikingly induced apoptosis in endothelial cells, independent of their effects on VEGF and bFGF. Furthermore, we found no evidence for direct biological effects of recombinant Tat on VEGF receptor binding, ERK activation, endothelial cell survival, or mitogenesis. These findings demonstrate novel properties of Tat-derived peptides and indicate that their major effect in endothelial cells is apoptosis independent of specific inhibition of VEGF receptor activation.

Adjuvant methods in macular hole surgery: intraoperative plasma-thrombin mixture and postoperative fluid-gas exchange

BACKGROUND AND OBJECTIVE

The optimal method for surgical management of idiopathic macular holes remains unknown. Adjuvant methods including intraoperative cytokines and postoperative fluid-gas exchange with and without laser have been described. We report on the safety and final results of routine intraoperative autologous plasma-thrombin mixture and postoperative fluid-gas exchange when necessary as an adjunct to the surgical therapy of this disease.

PATIENTS AND METHODS

A consecutive series of 114 patients (mean age 66.9 years) with primary idiopathic full thickness Stage II, III, and IV macular holes were primarily treated by vitrectomy, fluid/perfluorocarbon gas exchange, and application of autologous plasma-thrombin mixture to the macular hole. Visible epiretinal membranes were peeled but the normal appearing internal limiting membrane was not routinely stripped. Outcome measures included final Snellen visual acuity, rate of macular hole closure, complications, and number of supplemental procedures performed.

RESULTS

Closed at one month, were 110 of 121 (91%) macular holes, including two that underwent repeat fluid/gas exchange and laser within the first two weeks after surgery. At the time of final follow-up (mean: 10.9 months), 110 of 121 (91%) macular holes were closed. This included 8 of 9 eyes that had reopening of the macular hole between one and 21 months successfully treated by repeat fluid-gas exchange and 2 eyes that underwent a second successful pars plana vitrectomy, membrane peeling, and repeat fluid-gas exchange. Overall, 98 of 121 eyes overall (81%) were successfully treated by a single surgery; 94 of 121 (78%) achieved two lines or greater of visual improvement; 83 of 121 (69%) achieved 20/70 or better vision; and 47 eyes (39%) achieved 20/40 or better vision. Complications in this series included infectious endophthalmitis (1 eye), intraoperative retinal break (2 eyes), late retinal detachment (5 eyes), transient mild intraocular pressure elevation (46 eyes), inflammatory response (six eyes), epiretinal membrane (6 eyes), intraretinal hemorrhages (1 eye), and cataract (33 of 99 phakic eyes underwent cataract extraction during the follow-up).

CONCLUSION

A combination of intravitreal perfluorocarbon gas and autologous plasma-thrombin mixture (tissue glue) was well tolerated in most patients and did not result in any specific long-term complications. The use of supplemental fluid-gas exchange when necessary improved the final success rate. Further well-controlled and randomized studies will be required to determine the efficacy of this as an adjunct or alternative to other methods of treatment for macular holes.

Peptides encoded by exon 6 of VEGF inhibit endothelial cell biological responses and angiogenesis induced by VEGF

VEGF induces pathological angiogenesis and is an important target for the development of novel antiangiogenic molecules. In this study, we tested synthetic peptides based on the sequence of VEGF(189) for their ability to inhibit VEGF receptor binding and biological responses. We identified 12-amino acid peptides derived from exon 6 that inhibited VEGF binding to HUVECs, VEGF-stimulated ERK activation, and prostacyclin production. These peptides inhibited VEGF-induced mitogenesis, migration, and VEGF-dependent survival of endothelial cells, but caused no increase in apoptosis in the absence of VEGF. Exon 6-encoded peptides also caused a marked inhibition of VEGF-induced angiogenesis in vitro. Studies of effects of peptides on cross-linking of VEGF to its receptors and on binding of VEGF to porcine aortic endothelial cells expressing either KDR or neuropilin-1 showed that exon 6-encoded peptides effectively blocked the interaction of VEGF with both receptors. Exon 6-derived peptides caused release of bFGF from endothelial cells but inhibited bFGF-dependent ERK activation, cell proliferation and angiogenesis. Our findings indicate that VEGF exon 6-encoded peptides inhibit VEGF-induced angiogenesis, at least in part through inhibition of VEGF binding to KDR. In addition, exon 6-encoded peptides are also effective inhibitors of bFGF-mediated angiogenesis.

Fluorescein angiographic findings in ocular siderosis

PURPOSE

To report a case of siderosis from a retained intraocular iron foreign body manifesting localized retinal capillary nonperfusion documented by fluorescein angiography.

METHODS

Case Report. In a 35-year-old man with decreased vision in the left eye, studies included fundus photography, fluorescein angiography, visual field testing, and electrophysiology. Surgical foreign body extraction and histopathologic examination were performed.

RESULTS

Preoperatively, in the left eye, humphrey visual fields and electrophysiology testing revealed marked depression. Fluorescein angiography demonstrated nasal capillary nonperfusion with occlusion of the second- and third-order arterioles extending along a gradient from the foreign body. Microscopic examination of the lens capsule confirmed the diagnosis of siderosis secondary to a retained iron foreign body.

CONCLUSION

Extensive capillary nonperfusion may be associated with a retained iron intraocular foreign body, as documented by fluorescein angiography.

Clinical effectiveness of mandibular implant-retained overdentures

INTRODUCTION

The literature reports that the treatment of fully edentulous mandibles with implant-retained overdentures has become a recognised form of therapy: however long-term data on the success are limited. The aim of the present study was to describe the clinical effectiveness of mandibular implant-supported/retained overdentures in the management of a group of edentulous patients.

MATERIALS AND METHODS

The study group consisted of 59 consecutive edentulous patients attending the clinic of prosthetic dentistry at Cardiff Dental Hospital, who had been provided with implants in the mandible for complete overdenture retention. Several clinical parameters were examined in each patient: mobility of each implant, probing pocket depth, the presence or absence of plaque and calculus on each implant, bleeding index, marginal bone loss, jaw bone quality and quantity, complications that had occurred with the implants and patients opinions of the treatment.

DISCUSSION

Of implants placed, 97% remained in function. Three fixtures had been lost. There was a high frequency of bleeding on probing. Complications associated with treatment included damage or looseness of abutment screws, fracture of the bar, entrapment of food beneath the overdenture and looseness of the opposing non-implant-retained complete denture.

CONCLUSION

In general a very high degree of patient satisfaction with the implant-retained overdentures was recorded.

Leber hereditary optic neuropathy associated with antiretroviral therapy for human immunodeficiency virus infection

PURPOSE

Antiretroviral therapy has reduced the morbidity and mortality associated with human immunodeficiency virus (HIV) infection. However, side effects are increasingly recognized, including a commonly reported toxic mitochondrial myopathy. We report such a case of Leber hereditary optic neuropathy in a patient with antiretroviral therapy for HIV infection and speculate on a possible toxic etiologic role in the development of Leber hereditary optic neuropathy by a shared mitochondrial mechanism.

METHODS

Case Report. Bilateral optic disk abnormalities observed in a 38-year-old HIV positive man with a family history of Leber hereditary optic neuropathy were documented with fundus photography, color vision testing, and visual field testing. Mitochondrial DNA testing was used to confirm the genetic predisposition to Leber hereditary optic neuropathy.

RESULTS

Progressive bilateral optic nerve pallor temporally associated with the administration of antiretroviral medication was observed. Diagnostic testing revealed progressive visual field and color vision loss as well as a mitochondrial DNA mutation consistent with Leber hereditary optic neuropathy.

CONCLUSION

Antiretroviral therapy may be associated with the onset of Leber hereditary optic neuropathy in genetically predisposed patients.

Trabeculectomy with intraoperative mitomycin C versus 5-fluorouracil. Prospective randomized clinical trial

OBJECTIVE

To evaluate the relative efficacy and safety of 5-fluorouracil (5-FU) and mitomycin C (MMC) when used as adjuncts with primary trabeculectomy in eyes not at high risk for failure.

DESIGN

Prospective multicenter, randomized clinical trial.

PARTICIPANTS

One hundred thirteen patients with primary open-angle, pseudoexfoliative, pigmentary, or angle-closure glaucoma undergoing primary trabeculectomy were recruited.

METHODS

One eye of each patient was randomized to receive either 5-FU (50 mg/ml for 5 minutes) or MMC (0.4 mg/ml for 2 minutes).

MAIN OUTCOME MEASURES

Intraocular pressure (IOP), visual acuity, complications, and interventions were documented at fixed intervals after surgery. The study also examined progression of visual field loss, long-term complications, and bleb appearance 3 years after surgery.

RESULTS

Of the 108 patients with complete perioperative information, 54 eyes received 5-FU and 54 received MMC. The proportion of patients reaching different predefined target IOPs after surgery was slightly higher in the MMC group than in the 5-FU group. This difference was less than 25%, which would have been necessary to achieve statistical significance with a power of 0.8 and the sample size used. Likewise, there was no statistically significant difference between the groups with regard to mean preoperative IOP, complications, or interventions. Mean postoperative follow-up was 309 and 330 days in the 5-FU and MMC groups, respectively (P = 0.593).

CONCLUSIONS

5-Fluorouracil and MMC were found to be equally safe and effective adjuncts to primary trabeculectomy in the short- and medium-term postoperative periods.

Association study of dopamine receptor gene polymorphisms with drug-induced hallucinations in patients with idiopathic Parkinson's disease

Some patients with idiopathic Parkinson's disease experience hallucinations as a result of treatment with levodopa and dopamine agonists. There is evidence for some heterogeneity in these hallucinating patients based on duration of Parkinson's disease at onset of hallucinations. We compared the frequency of polymorphisms in the dopamine D2 and D3 receptor genes between patients with drug-induced hallucinations and non-hallucinating patients. Two polymorphisms close to DRD2 and one in DRD3 were studied. No association was found with the whole group of hallucinating patients and their controls. However, an association was found with late-onset hallucinations and the C allele of the TaqIA polymorphism, 10.5 kb 3' to DRD2. This polymorphism may be in linkage disequilibrium with a mutation in DRD2 or a nearby gene that predisposes to drug-induced hallucinations which occur later in the course of idiopathic Parkinson's disease.

Function and assembly of nuclear pore complex proteins

Nuclear pore complexes (NPCs) are extremely elaborate structures that mediate the bidirectional movement of macromolecules between the nucleus and cytoplasm. The current view of NPC organization features a massive symmetrical framework that is embedded in the double membranes of the nuclear envelope. It embraces a central channel of as yet ill-defined structure but which may accommodate particles with diameters up to 26 nm provided that they bear specific import/export signals. Attached to both faces of the central framework are peripheral structures, short cytoplasmic filaments, and a nuclear basket assembly, which interact with molecules transiting the NPC. The mechanisms of assembly and the nature of NPC structural intermediates are still poorly understood. However, mutagenesis and expression studies have revealed discrete sequences within certain NPC proteins that are necessary and sufficient for their appropriate targeting. In addition, some details are emerging from observations on cells undergoing mitosis where the nuclear envelope is disassembled and its components, including NPC subunits, are dispersed throughout the mitotic cytoplasm. At the end of mitosis, all of these components are reutilized to form nuclear envelopes in the two daughter cells. To date, it has been possible to define a time course of postmitotic assembly for a group of NPC components (CAN/Nup214, Nup153, POM121, p62 and Tpr) relative to the integral inner nuclear membrane protein LAP2 and the NPC membrane glycoprotein gp210. Nup153, a dynamic component of the nuclear basket, associates with chromatin towards the end of anaphase coincident with, although independent of, the inner nuclear membrane protein, LAP2. Assembly of the remaining proteins follows that of the nuclear membranes and occurs in the sequence POM121, p62, CAN/Nup214 and gp210/Tpr. Since p62 remains as a complex with three other NPC proteins (p58, p54, p45) during mitosis, and CAN/Nup214 maintains a similar interaction with its partner, Nup84, the relative timing of assembly of these additional four proteins may also be inferred. These observations suggest that there is a sequential association of NPC proteins with chromosomes during nuclear envelope reformation and the recruitment of at least eight of these precedes that of gp210. These findings support a model in which it is POM121 rather than gp210 that defines initial membrane-associated NPC assembly intermediates and which may therefore represent an essential component of the central framework of the NPC.

Sequential recruitment of NPC proteins to the nuclear periphery at the end of mitosis

Nuclear pore complexes (NPCs) are extremely elaborate structures that mediate the bidirectional movement of macromolecules between the nucleus and cytoplasm. With a mass of about 125 MDa, NPCs are thought to be composed of 50 or more distinct protein subunits, each present in multiple copies. During mitosis in higher cells the nuclear envelope is disassembled and its components, including NPC subunits, are dispersed throughout the mitotic cytoplasm. At the end of mitosis, all of these components are reutilized. Using both conventional and digital confocal immunofluorescence microscopy we have been able to define a time course of post-mitotic assembly for a group of NPC components (CAN/Nup214, Nup153, POM121, p62 and Tpr) relative to the integral nuclear membrane protein LAP2 and the NPC membrane glycoprotein gp210. Nup153, a component of the nuclear basket, associates with chromatin towards the end of anaphase, in parallel with the inner nuclear membrane protein, LAP2. However, immunogold labeling suggests that the initial Nup153 chromatin association is membrane-independent. Assembly of the remaining proteins follows that of the nuclear membranes and occurs in the sequence POM121, p62, CAN/Nup214 and gp210/Tpr. Since p62 remains as a complex with three other NPC proteins (p58, 54, 45) during mitosis and CAN/Nup214 maintains a similar interaction with its partner, Nup84, the relative timing of assembly of these additional four proteins may also be inferred. These observations suggest that there is a sequential association of NPC proteins with chromosomes during nuclear envelope reformation and the recruitment of at least eight of these precedes that of gp210. These findings support a model in which it is POM121 rather than gp210 that defines initial membrane-associated NPC assembly intermediates.

Nup153 is an M9-containing mobile nucleoporin with a novel Ran-binding domain

We employed a phage display system to search for proteins that interact with transportin 1 (TRN1), the import receptor for shuttling hnRNP proteins with an M9 nuclear localization sequence (NLS), and identified a short region within the N-terminus of the nucleoporin Nup153 which binds TRN1. Nup153 is located at the nucleoplasmic face of the nuclear pore complex (NPC), in the distal basket structure, and functions in mRNA export. We show that this Nup153 TRN1-interacting region is an M9 NLS. We found that both import and export receptors interact with several regions of Nup153, in a RanGTP-regulated fashion. RanGTP dissociates Nup153-import receptor complexes, but is required for Nup153-export receptor interactions. We also show that Nup153 is a RanGDP-binding protein, and that the interaction is mediated by the zinc finger region of Nup153. This represents a novel Ran-binding domain, which we term the zinc finger Ran-binding motif. We provide evidence that Nup153 shuttles between the nuclear and cytoplasmic faces of the NPC. The presence of an M9 shuttling domain in Nup153, together with its ability to move within the NPC and to interact with export receptors, suggests that this nucleoporin is a mobile component of the pore which carries export cargos towards the cytoplasm.

The safety and effectiveness of remifentanil as an adjunct sedative for regional anesthesia

We assessed the sedative potential of continuous infusions of remifentanil with a validated composite alertness scale in 160 patients (ASA physical status I or II) undergoing hip replacement surgery with spinal block (n = 61) or hand surgery using brachial plexus block (n = 93). They were randomized to receive one of the following initial dose regimens in double-blinded fashion: placebo or 0.04, 0.07, or 0.1 microg x kg(-1) x min(-1) remifentanil subsequently titrated to effect. Additional midazolam IV was allowed for adequate sedation as required. The combined analysis of both surgery groups revealed a dose-related increase in achievement of sedation level > or =2 within 15 min of the start of the study drug infusion; all remifentanil dose comparisons with placebo reached significance (P < 0.001). The remifentanil 50% effective dose for a composite sedation level > or =2 within 15 min of the start of drug infusion was estimated as 0.043 microg x kg(-1) x min(-1) (95% confidence interval 0.01, 0.059). The requirement for midazolam decreased with increasing remifentanil dose compared with placebo (P < 0.001). The median time to return to alertness after the end of infusion was 10-12 min in the remifentanil groups and 5 min in the placebo group. Significant incidences of nausea, pruritus, sweating, and respiratory depression were reported during remifentanil infusions compared with placebo. The data suggest that remifentanil may be useful for supplementation of regional anesthesia, provided that ventilation is carefully monitored.

IMPLICATIONS

In this dose-finding, placebo-controlled study, remifentanil infusions were used to provide sedation during spinal and brachial plexus regional anesthesia. The 50% effective dose for achievement of sedation was 0.043 microg x kg(-1) x min(-1). Return to alertness occurred after 10-12 min (median time). Remifentanil infusions can be used to supplement regional anesthesia, but this requires careful monitoring of ventilation.

The effect of silicone ocular surgical devices on serum IgG binding to silicones

PURPOSE

To determine whether silicone materials used in retinal detachment repair and cataract surgery increase serum IgG binding to silicone and identify correlations with complications of ocular surgery.

METHODS

Serum from 49 patients who had ocular surgery using silicone materials was examined. Patient groups included scleral buckling (n = 25), silicone oil tamponade (n = 3), scleral buckling and silicone oil tamponade (n = 9), and silicone lens implants after cataract extraction (n = 12). Convalescent samples for all patients and preoperative samples from 19 patients (18 scleral buckling and one silicone oil tamponade) were examined. Postoperative complications were monitored for up to 108 months (mean, 10.7 months; mode, 1.5 months; range, 1 to 108 months). Samples were evaluated for the extent of IgG binding to silicones using a micromodification of a previously described enzyme-linked immunosorbent assay method.

RESULTS

In 19 patients, IgG binding levels in preoperative samples were 21 arbitrary units (AU) or less. Of the 25 buckling patients, one developed complications; however, in all patients the postoperative levels of IgG binding to silicone were low (2.2 to 20.0 AU). Although four silicone lens patients developed mild complications, none displayed postoperative IgG binding levels of greater than 20 AU. Three patients who underwent both scleral buckling and silicone oil tamponade developed complications; one of these patients, who was also noted to have systemic connective tissue disease, had a significant elevation in postoperative serum IgG binding to silicone.

CONCLUSIONS

Statistically significant elevations of serum IgG binding to silicone were noted postoperatively in only one patient who had a systemic connective tissue disease. The complication rate and frequency of enhanced serum IgG binding to silicone was low, making correlations to surgical complications difficult. Examination of matched samples suggested that if ocular exposure to silicone implants enhances the level of serum IgG binding to silicones, it must be a rare event that should not alter the clinical use of these important devices.

Remifentanil in combination with propofol for spontaneous ventilation anaesthesia

We have investigated the effect of four doses of remifentanil on the incidence of respiratory depression and somatic response at incision. Remifentanil was administered as a loading dose of 0.125, 0.25, 0.375 or 0.5 microgram kg-1 and at a maintenance infusion rate of 0.025, 0.05, 0.075 or 0.1 microgram kg-1 min-1, respectively, with an infusion of propofol 6 mg kg-1 h-1. Responses occurred in 88% of patients with remifentanil 0.025 microgram kg-1 min-1 compared with 30-40% in the other groups. Respiratory depression after incision increased from 6% with remifentanil 0.025 microgram kg-1 min-1 to 73% with 0.1 microgram kg-1 min-1. Increases in propofol infusion rate to 7.2-8.4 mg kg-1 h-1 produced adequate maintenance of anaesthesia. Reductions in remifentanil doses to 0.025-0.05 microgram kg-1 min-1 resulted in adequate respiration at the end of surgery in 88% of patients. Maintenance infusions of the two drugs for spontaneous ventilation are likely to be in these ranges. However, the ideal loading doses and infusion rates for induction remain to be established.