Phospholemman does not participate in forskolin-induced swine carotid artery relaxation.

Phosphorylation of phospholemman (PLM) on ser68 has been proposed to at least partially mediate cyclic AMP (cAMP) mediated relaxation of arterial smooth muscle. We evaluated the time course of the phosphorylation of phospholemman (PLM) on ser68, myosin regulatory light chains (MRLC) on ser19, and heat shock protein 20 (HSP20) on ser16 during a transient forskolin-induced relaxation of histamine-stimulated swine carotid artery. We also evaluated the dose response for forskolin- and nitroglycerin-induced relaxation in phenylephrine-stimulated PLM-/- and PLM+/+ mice. The time course for changes in ser19 MRLC dephosphorylation and ser16 HSP20 phosphorylation was appropriate to explain the forskolin-induced relaxation and the recontraction observed upon washout of forskolin. However, the time course for changes in ser68 PLM phosphorylation was too slow to explain forskolin-induced changes in force. There was no difference in the phenylephrine contractile dose response or in forskolin-induced relaxation dose response observed in PLM-/- and PLM+/+ aortae. In aortae precontracted with phenylephrine, nitroglycerin induced a slightly, but significantly greater relaxation in PLM-/- compared to PLM+/+ aortae. These data are consistent with the hypothesis that ser19 MRLC dephosphorylation and ser16 HSP20 phosphorylation are involved in forskolin-induced relaxation. Our data suggest that PLM phosphorylation is not significantly involved in forskolin-induced arterial relaxation.

Cilia, primary ciliary dyskinesia and molecular genetics.

Primary ciliary dyskinesia (PCD) is a phenotypically and genetically heterogeneous condition in which three genetic mutations have already been identified. The primary defect is in the ultrastructure or function of cilia, highly complex organelles that are structurally related to the flagella of sperm and protozoa. The clinical features of PCD include recurrent sinopulmonary infections, subfertility and laterality defects; the latter due to ciliary dysfunction at the embryological node. Completion of the human genome sequence has accelerated the identification and characterisation of disease genes, and the current molecular strategy in PCD includes candidate gene analysis, positional cloning, model organism analysis and proteomic analysis. The identification of these genes will provide new insights into the molecular mechanisms involved in the assembly and function of cilia and the pathway that determines left-right axis in man. This may also allow the development of new methods for diagnosis, prevention and treatment of PCD.

Primary ciliary dyskinesia: age at diagnosis and symptom history.

UNLABELLED: Age at diagnosis and the symptom history of children with primary ciliary dyskinesia (PCD) are described by reviewing the case notes in the paediatric PCD clinic. Mean age at diagnosis was 4.4 y despite a history of neonatal respiratory distress in 37/55 cases, situs inversus in 38/55 cases and early onset troublesome rhinitis in 42/55. CONCLUSION: Diagnosis of PCD is often delayed despite the presence of typical symptoms early in life. The key clinical features of unexplained neonatal respiratory distress, early onset rhinitis, situs inversus and a productive cough are highlighted, which, especially when occurring in combination, makes early referral for specific testing for PCD mandatory.

Immune response genes modulate serologic responses to Vibrio cholerae TcpA pilin peptides.

Cholera is an enteric disease caused by Vibrio cholerae. Toxin-coregulated pilus (TCP), a type 4 pilus expressed by V. cholerae, is a cholera virulence factor that is required for host colonization. The TCP polymer is composed of subunits of TcpA pilin. Antibodies directed against TcpA are protective in animal models of cholera. While natural or recombinant forms of TcpA are difficult to purify to homogeneity, it is anticipated that synthesized TcpA peptides might serve as immunogens in a subunit vaccine. We wanted to assess the potential for effects of the immune response (Ir) gene that could complicate a peptide-based vaccine. Using a panel of mice congenic at the H-2 locus we tested the immunogenicity of TcpA peptide sequences (peptides 4 to 6) found in the carboxyl termini of both the classical (Cl) and El Tor (ET) biotypes of TCP. Cl peptides have been shown to be immunogenic in CD-1 mice. Our data clearly establish that there are effects of the Ir gene associated with both biotypes of TcpA. These effects are dynamic and dependent on the biotype of TcpA and the haplotypes of the host. In addition to the effects of the classic class II Ir gene, class I (D, L) or nonclassical class I (Qa-2) may also affect immune responses to TcpA peptides. To overcome the effects of the class II Ir gene, multiple TcpA peptides similar to peptides 4, 5, and 6 could be used in a subunit vaccine formulation. Identification of the most protective B-cell epitopes of TcpA within a particular peptide and conjugation to a universal carrier may be the most effective method to eliminate the effects of the class II and class I Ir genes.

Axonemal beta heavy chain dynein DNAH9: cDNA sequence, genomic structure, and investigation of its role in primary ciliary dyskinesia.

Dyneins are multisubunit protein complexes that couple ATPase activity with conformational changes. They are involved in the cytoplasmatic movement of organelles (cytoplasmic dyneins) and the bending of cilia and flagella (axonemal dyneins). Here we present the first complete cDNA and genomic sequences of a human axonemal dynein beta heavy chain gene, DNAH9, which maps to 17p12. The 14-kb-long cDNA is divided into 69 exons spread over 390 kb. The cDNA sequence of DNAH9 was determined using a combination of methods including 5' rapid amplification of cDNA ends, RT-PCR, and cDNA library screening. RT-PCR using nasal epithelium and testis RNA revealed several alternatively spliced transcripts. The genomic structure was determined using three overlapping BACs sequenced by the Whitehead Institute/MIT Center for Genome Research. The predicted protein, of 4486 amino acids, is highly homologous to sea urchin axonemal beta heavy chain dyneins (67% identity). It consists of an N-terminal stem and a globular C-terminus containing the four P-loops that constitute the motor domain. Lack of proper ciliary and flagellar movement characterizes primary ciliary dyskinesia (PCD), a genetically heterogeneous autosomal recessive disorder with respiratory tract infections, bronchiectasis, male subfertility, and, in 50% of cases, situs inversus (Kartagener syndrome, KS). Dyneins are excellent candidate genes for PCD and KS because in over 50% of cases the ultrastructural defects of cilia are related to the dynein complex. Genotype analysis was performed in 31 PCD families with two or more affected siblings using a highly informative dinucleotide polymorphism located in intron 26 of DNAH9. Two families with concordant inheritance of DNAH9 alleles in affected individuals were observed. A mutation search was performed in these two "candidate families," but only polymorphic variants were found. In the absence of pathogenic mutations, the DNAH9 gene has been excluded as being responsible for autosomal recessive PCD in these families.

No deleterious mutations in the FOXJ1 (alias HFH-4) gene in patients with primary ciliary dyskinesia (PCD).

The transcription factor FOXJ1 (alias HFH-4 or FKHL13) of the winged-helix/forkhead family is expressed in cells with cilia or flagella, and seems to be involved in the regulation of axonemal structural proteins. The knockout mouse Foxj1(-/-) shows abnormalities of organ situs, consistent with random determination of left-right asymmetry, and a complete absence of cilia. The human FOXJ1 gene which maps to chromosome 17q, is thus an excellent candidate gene for Kartagener Syndrome (KS), a subphenotype of Primary Ciliary Dyskinesia (PCD), characterized by bronchiectasis, chronic sinusitis and situs inversus. We have collected samples from 61 PCD families, in 31 of which there are at least two affected individuals. Two families with complete aciliogenesis, and six families, in which the affected members have microsatellite alleles concordant for a locus on distal chromosome 17q, were screened for mutations in the two exons and intron-exon junctions of the FOXJ1 gene. No sequence abnormalities were observed in the DNAs of the affected individuals of the selected families. These results demonstrate that the FOXJ1 gene is not responsible for the PCD/KS phenotype in the families examined.

Use of subjective global assessment to identify nutrition-associated complications and death in geriatric long-term care facility residents.

OBJECTIVE: The primary objective of this study was to assess the use of Subjective Global Assessment to identify nutrition-associated complications and death in a geriatric population. A secondary objective was to evaluate the ability of Subjective Global Assessment to identify geriatric residents of long-term care facilities who were undernourished or at risk for developing undernutrition. METHODS: Fifty-three consecutive residents who were > or = 65 years of age and had been residing in a long-term care facility for < 2 weeks were enrolled in the study. The Subjective Global Assessment Classification technique was performed according to the procedure outlined by Detsky and colleagues. Residents were classified as well-nourished (A), mild/moderately undernourished (B) or severely undernourished (C). In addition, a Subjective Global Assessment Composite Score was derived. Subjective Global Assessment measures were compared with two traditional objective measurements of nutritional status: serum albumin and serum total cholesterol. Outcome measurements of nutrition-associated complications were determined over a 3-month period by recording the incidence of major infections, decubitus ulcers, nutrition-related hospital readmissions, and mortality. RESULTS: Sixteen residents (30.2%) were categorized as Subjective Global Assessment class A, 28 residents (52.8%) were class B, and 9 residents (17%) were class C. A significant association was found between nutritional status as determined by Subjective Global Assessment Composite Score and nutrition-associated complications (p<0.05). Subjective Global Assessment Classification was related to death (p<0.05) with severely undernourished residents having the highest mortality rate. Hypoalbuminemia only demonstrated a significant relationship with nutrition-associated complications (p<0.05), whereas hypocholesterolemia was associated with death (p<0.05). CONCLUSIONS: Subjective Global Assessment of nutritional status appears to be a simple, noninvasive and cost-effective tool for assessing nutritional status of geriatric residents in long-term care facilities. This assessment tool is also beneficial for identifying patients with increased risk of nutrition-associated complications as well as death.

A locus for primary ciliary dyskinesia maps to chromosome 19q.

Primary ciliary dyskinesia is an autosomal recessive condition characterised by chronic sinusitis, bronchiectasis, and subfertility. Situs inversus occurs in 50% of cases (Kartagener syndrome). It has an estimated incidence of 1 in 20 000 live births. The clinical phenotype is caused by defective ciliary function associated with a range of ultrastructural abnormalities including absent dynein arms, absent radial spokes, and disturbed ciliary orientation. The molecular genetic basis is unknown. A genome scan was performed in five Arabic families. Using GENEHUNTER, a maximal multipoint lod score (HLOD) of 4.4 was obtained on chromosome 19q13.3-qter at alpha (proportion of linked families) = 0.7. A 15 cM critical region is defined by recombinations at D19S572 and D19S218. These data provide significant evidence for a PCD locus on chromosome 19q and confirm locus heterogeneity.

Primary ciliary dyskinesia: a genome-wide linkage analysis reveals extensive locus heterogeneity.

Primary ciliary dyskinesia (PCD), or immotile cilia syndrome (ICS), is an autosomal recessive disorder affecting ciliary movement with an incidence of 1 in 20000-30000. Dysmotility to complete immotility of cilia results in a multisystem disease of variable severity with recurrent respiratory tract infections leading to bronchiectasis and male subfertility. Ultrastructural defects are present in ciliated mucosa and spermatozoa. Situs inversus (SI) is found in about half of the patients (Kartagener syndrome). We have collected samples from 61 European and North American families with PCD. A genome-wide linkage search was performed in 31 multiplex families (169 individuals including 70 affecteds) using 188 evenly spaced (19cM average interval) polymorphic markers. Both parametric (recessive model) and non-parametric (identity by descent allele sharing) linkage analyses were used. No major locus for the majority of the families was identified, although the sample was powerful enough to detect linkage if 40% of the families were linked to one locus. These results strongly suggest extensive locus heterogeneity. Potential genomic regions harbouring PCD loci were localised on chromosomes 3p, 4q, 5p, 7p, 8q, 10p, 11q, 13q, 15q, 16p, 17q and 19q. Linkage analysis using PCD families with a dynein arm deficiency provided 'suggestive' evidence for linkage to chromosomal regions 8q, 16pter, while analyses using only PCD families with situs inversus resulted in 'suggestive' scores for chromosomes 8q, and 19q.

Primary ciliary dyskinesia (PCD).

This article summarizes the current state of the scientific and clinical knowledge that relates to primary ciliary dyskinesia (PCD). Although PCD is a rare disease with a prevalence of 1 in 20,000 it has a well recognized morbidity. It is believed that an accurate diagnosis and the application of appropriate management can significantly reduce this morbidity. The cilia themselves are highly complicated organelles that perform important functions, particularly in the respiratory and reproductive tracts, and they have been the focus of many years of research. Our current knowledge of ciliary function and mucociliary clearance is summarized, and the relationship with laterality defects is discussed. A phenotype resembling PCD is also seen in animal models, and some of these are described before reviewing the clinical aspects of PCD in humans and new developments in the field that may have implications for the future investigation and management of affected individuals.

Driving simulation study: bilateral array multifocal versus bilateral AMO monofocal intraocular lenses.

PURPOSE: To determine whether differences exist in the driving performance of patients with bilateral Array multifocal intraocular lenses (IOLs) and those with bilateral AMO monofocal IOLs under low-contrast environmental conditions. SETTING: The Iowa Driving Simulator at the Center for Computer Aided Design, the University of Iowa, Iowa City, Iowa, USA. METHODS: This prospective study was a test-operator-masked, parallel-group comparison of the driving performance of 33 bilateral multifocal IOL patients and 33 bilateral monofocal IOL patients from the U.S. Array Multifocal study. Driving performance was evaluated under 3 poor visibility conditions (clear weather at night, clear weather at night in the presence of a glare source, and fog). Measures of performance included recognition rates and distances for signs, as well as detection rates, distances, and avoidance behaviors for hazards. Contrast acuity and sensitivity were also measured to evaluate possible correlations with driving performance. RESULTS: No statistically significant differences between the IOL groups were found in 26 of 30 comparisons (86.7%). The monofocal group performed better than the multifocal group in comparisons in which there were statistically significant differences: the percentage of correctly recognized warning signs at night in clear weather (P = .028), sign recognition distances for guide (P = .030) and warning (P = .036) signs in fog, and the detection distance for 1 of 4 hazards (suitcase; P = .026). Correlation coefficients between driving performance and low-contrast acuity and sensitivity were statistically significant; however, they were low and not likely predictive of driving performance. CONCLUSION: Differences between patients with bilateral multifocal IOLs and those with bilateral monofocal IOLs were detected; however, the results indicate no consistent difference in driving performance and safety.

Site-specific pharmacokinetics and pharmacodynamics of intramuscular meperidine in elderly postoperative patients.

OBJECTIVE: To examine and compare the pharmacokinetics and pharmacodynamics of meperidine when administered intramuscularly at gluteal and deltoid sites in elderly postoperative patients. DESIGN: Prospective, randomized investigation. SETTING: Tertiary care university teaching hospital. PATIENTS: Fourteen patients 60 years of age or older who were undergoing general surgery. INTERVENTION: A single dose of meperidine 0.75 mg/kg given intramuscularly at either a deltoid or gluteal site. MAIN OUTCOME MEASURES: Pharmacokinetic (based on concentration-time curves) and pharmacodynamic (i.e., pain scales, need for additional pain medication) comparisons were made, based on site of meperidine injection. RESULTS: No statistically significant differences were found in the maximum plasma concentration, volume of distribution, or clearance of meperidine by site of injection. Substantial interpatient variability in pharmacokinetic parameters was noted for both sites (range of maximum concentrations: 191-500 ng/mL gluteal, 166-374 ng/mL deltoid). Although pain scores were similar for the two groups, four of the patients in the group given gluteal injection required additional breakthrough pain management within 4 hours of meperidine injection compared with one patient in the group given deltoid injection. CONCLUSIONS: There is no obvious relationship between meperidine pharmacokinetic and pharmacodynamic parameters, regardless of intramuscular injection site. Breakthrough pain is common when patients are given intramuscular injections postoperatively, particularly when the gluteal route is used. When meperidine is used for analgesia in elderly postoperative patients, consideration should be given to more rapid and predictable routes (e.g., intravenous injection) of meperidine administration.

Safety of gadoteridol injection: U.S. clinical trial experience.

As part of the clinical evaluation of gadoteridol injection, intravenous doses ranging from 0.05 to 0.3 mmol/kg were administered to 1,709 patients and volunteers. Safety monitoring included pre- and postdose physical examinations, vital signs, and clinical laboratory values. Adverse event recording included occurrence, duration, severity, relationship to injection, and clinical importance. No clinically important changes in physical examination results, electrocardiograms, or vital signs were attributed to gadoteridol injection except for one case of hypotension. Four clinically important changes in laboratory values possibly or definitely related to the contrast agent were noted in two patients (0.1%). Adverse events were recorded in 118 subjects (6.9%), including nausea in 24 subjects (1.4%) and taste perversion in 22 subjects (1.3%). All other adverse events occurred with a frequency of less than 1%. Adverse events related to contrast agent administration occurred in 79 subjects (4.6%). Gadoteridol injection demonstrated excellent clinical safety and patient tolerance at various doses and injection rates.