Hox cluster genomics in the horn shark, Heterodontus francisci

Reconstructing the evolutionary history of Hox cluster origins will lead to insights into the developmental and evolutionary significance of Hox gene clusters in vertebrate phylogeny and to their role in the origins of various vertebrate body plans. We have isolated two Hox clusters from the horn shark, Heterodontus francisci. These have been sequenced and compared with one another and with other chordate Hox clusters. The results show that one of the horn shark clusters (HoxM) is orthologous to the mammalian HoxA cluster and shows a structural similarity to the amphioxus cluster, whereas the other shark cluster (HoxN) is orthologous to the mammalian HoxD cluster based on cluster organization and a comparison with noncoding and Hox gene-coding sequences. The persistence of an identifiable HoxA cluster over an 800-million-year divergence time demonstrates that the Hox gene clusters are highly integrated and structured genetic entities. The data presented herein identify many noncoding sequence motifs conserved over 800 million years that may function as genetic control motifs essential to the developmental process.

MULTICLUSTAL: a systematic method for surveying Clustal W alignment parameters

MULTICLUSTAL is a Perl script designed to automate the process of alignment parameter choice for Clustal W with the goal of generating high quality multiple sequence alignments.

Identification of two hERR2-related novel nuclear receptors utilizing bioinformatics and inverse PCR

Identification of novel nuclear receptors based on the highly conserved DNA-binding domain (DBD) has previously depended mainly on low stringency hybridization of cDNA libraries and degenerate PCR. Establishment of the expressed sequence tag (EST) database in recent years has provided an alternative approach for the discovery of novel members of gene families. The rate-limiting step is the conversion of ESTs to full-length cDNA. This article describes the identification of two novel nuclear receptors (hERRbeta2 and hERRgamma2) related to human estrogen-receptor-related receptor 2 (hERR2) by mining the EST database and retrieving of full-length cDNA via inverse PCR on subdivided primary cDNA library pools. The deduced protein sequences of hERRbeta2 and hERRgamma2 contain 500 and 458 amino acid (aa) residues respectively. Sequence analysis revealed that hERRbeta2 and hERRgamma2 respectively share 95% and 77% overall aa sequence identity with hERR2. However, the extra C-terminal domain in hERRbeta2 and extra N-terminal domain in hERRgamma2 are not present in the closely related hERR2 or mouse ERR2 (mERR2). Extensive sequence verification revealed that hERR2 previously reported as a human gene is actually a rat gene, whereas hERRbeta2 is the true human ortholog of hERR2 and mERR2. Tissue distribution studies showed that hERRgamma2 was expressed in a broader panel of tissues at a higher level than hERRbeta2. hERRbeta2 was mapped to cytogenetic locus 14q24.3 approximately -14q31, a region containing multiple loci involved in genetic diseases, including Alzheimer and diabetes. hERRgamma2 was mapped to 1q32. Given the high sequence homology between hERRbeta2 and mERR2, the two receptors may have similar biological function in vivo.

Identification and cloning of an orphan G protein-coupled receptor of the glycoprotein hormone receptor subfamily

Mining of the EST database identified a human EST that was predicted to encode a novel member of the glycoprotein hormone receptor subfamily. Based on the sequence information, the full-length coding region of this gene was isolated and sequenced. This gene, designated HG38, is predicted to encode a polypeptide of 907 amino acid residues with a putative signal peptide sequence at its very N-terminus. HG38 is most closely related to members of the glycoprotein hormone receptor subfamily with approximately 35% overall identity at the protein sequence level. As with the glycoprotein hormone receptors, HG38 contains a long extracellular domain with a total of 16 leucine-rich repeats. Northern blot analysis showed that HG38 was expressed in skeletal muscle, placenta, spinal cord, and various regions of the brain. Radiation hybrid mapping placed HG38 into human chromosome 12q22-23. HG38 is most likely to be a receptor for a novel class of glycoprotein ligands.

Clinical significance of a new P wave lead vector for pacemaker follow-up of atrial functions

Patient welfare requires routine follow-up procedures of implantable pacemakers. However, the assessment of atrial sensing and pacing functions in implantable pacemakers is often a challenge due to difficult identification of low amplitude P waves on surface electrocardiograms (ECGs). A previous body surface mapping study suggested that a novel P wave lead vector (P lead) had larger root mean square values than other standard leads. However, for pacemaker follow-up procedures, peak-to-peak amplitudes are more relevant than root mean square values. In this study, the peak-to-peak amplitudes of intrinsic and paced P waves recorded from surface ECG standard lead II and the P lead were compared. In addition, intrinsic and paced R waves were also compared. Data recorded from 15 patients undergoing electrophysiological studies indicated that peak-to-peak amplitudes of the P lead were significantly larger than standard lead II: 24% for intrinsic P waves, 30% for paced P waves, and 72% for intrinsic R waves. In addition, the P lead amplitude of paced R waves showed a nonsignificant increase of 24% compared with standard lead II. Therefore, the use of this new lead vector may improve the clinical ease-of-use and reduce the time required for follow-up procedures of implantable pacemakers for atrial sensing and pacing assessments.

Disparities in access to family planning services in Jamaica

In order to improve the effectiveness and subtainability of the family planning programme, the National Family Planning Board has devised a strategy to shift users to longer-acting methods and increase the role of the private sector. To design interventions, a better understanding of existing services was thought to be necessary. This study examines the distribution of family planning service delivery points in Jamaica and the services offered by the public and private sectors through an examination of records and questionnaire interviews. The study found that, because of the concentration of private sector providers-the main outlets for longer-acting methods-in urban areas, rural areas had poor access to these methods. Because rural areas are not attractive to private sector providers, the public sector should recognize the need to continue to serve these areas.

The effect of basic fibroblast growth factor on the blood flow and morphologic features of a latissimus dorsi cardiomyoplasty

Previous studies designed to determine whether latissimus cardiomyoplasty could be used to revascularize ischemic myocardium showed that after operation the latissimus was ischemic and had severely deteriorated. This study was undertaken to determine whether basic fibroblast growth factor, a potent angiogenic peptide, would improve the vascularity of the latissimus and enhance collateral formation between the muscle of the cardiomyoplasty and ischemic myocardium. In goats, myocardial ischemia was induced with an ameroid constrictor and cardiomyoplasty performed. The latissimus was continuously stimulated electrically at 2 Hz for 6 weeks and given four weekly bolus injections of human recombinant basic fibroblast growth factor (80 micrograms infused into the left subclavian artery). In eight animals, rates of regional blood flow were measured and both the heart and latissimus were evaluated histochemically. The latissimus blood flow rate was 0.114 +/- 0.029 ml/gm per minute, which was three times greater than that of historical controls (chronically stimulated latissimus cardiomyoplasty without basic fibroblast growth factor treatment; 0.042 +/- 0.007 ml/gm per minute, p < 0.05). Associated with the improved blood flow, there was significantly less evidence of skeletal muscle fiber dropout and muscle fibrosis in the animals treated with basic fibroblast growth factor. Latissimus-derived collateral flow to ischemic myocardium developed in five of the eight goats and averaged 0.288 +/- 0.075 ml/gm per minute. This flow was 42.8% +/- 15.7% (n = 5) of the flow required by normal myocardium (which was 0.728 +/- 0.095 ml/gm per minute). This value for latissimus-derived collateral blood flow was almost twice that of the historical controls (24.0% +/- 3.9%), but the increase did not achieve statistical significance (p = 0.08). These results hold the promise that basic fibroblast growth factor treatment might enhance the formation of extramyocardial collaterals to the heart and improve skeletal muscle function.

Assessing family planning service-delivery practices: the case of private physicians in Jamaica

This report presents the results of a study of the family planning service-delivery practices of private physicians in Jamaica. All 367 private physicians in Jamaica who offer family planning services, counseling, or referral were included in the survey. The study revealed that a client seeking services might be given a method by one provider and not by another, and that the methods clients use are likely to be influenced by the providers' preferences. Private physicians in Jamaica are in need of access to current international guidance on contraceptive methods and service practices.

Quality of care among Jamaican private physicians offering family planning services

The National Family Planning Board is the agency of Government empowered to prepare, carry out and promote family planning programs in Jamaica. The Board has prioritized the expansion and sustainability of family planning services in large part through encouraging the participation of the private sector. To enhance the availability, acceptability and effectiveness of private physician family planning services, information was collected on the service practices of 90% of physicians, through face to face interviews. Bruce's framework was used to evaluate the findings of the study. The study indicated that: A wide variety of contraceptives are available - Basic equipment and adequate supplies are in place for the provision of services - Provider bias, inappropriate contraindicators and process and scheduling hurdles exist. The major recommendations relate to the: Revision of norms and guidelines for all contraceptives - Continuation of contraceptive technology updates for private physicians - Revision of legal/regulatory barriers which restrict access to some contraceptives for certain target groups.

Monozygotic twins discordant for the Russell-Silver syndrome

Russell-Silver syndrome (RSS) is a pattern of malformation characterized by intrauterine and postnatal growth retardation, limb asymmetry, triangular face, and hypospadias. We report on a patient, from a triplet pregnancy, who was one of identical male twins discordant for RSS. R.B. was a 710-g male born at 33 weeks of gestation, with hypospadias, chordee, and undescended testes. He had a normal 46,XY karyotype and no renal abnormalities. Female triplet A weighed 1,843 g, and male triplet B weighed 1,920 g. Both had normal physical findings and neonatal period. R.B. was first seen by us at age 6 7/12 years with short stature, triangular and asymmetric face, lower limb length discrepancy, and surgically repaired genital anomalies. Growth hormone testing results were normal. At age 8 7/12 years the brothers appeared physically identical except for size, with a height differential of 114.25 vs. 121.5 cm. Testing to establish biological zygosity was performed using VNTR (variable number tandem repeat) DNA probes YNH24 (D2S44), CMM101 (D14S13), EFD52 (D17S26), TBQ7 (D10S28), and 3'HVR (D16S85), PCR loci MCT118 (D1S80), and HLA-DQ alpha. These data indicate a > 99.99% probability of triplets B and C being monozygotic twins. While most occurrences of RSS are sporadic, familial cases suggesting autosomal dominance have been reported. Three other cases of probable monozygotic twins with RSS have been described. The significance of this confirmation of discordance in determining the cause of RSS is discussed.

Rapid molecular cytogenetic analysis of X-chromosomal microdeletions: fluorescence in situ hybridization (FISH) for complex glycerol kinase deficiency

Diagnosis of X-chromosomal microdeletions has relied upon the traditional methods of Southern blotting and DNA amplification, with carrier identification requiring time-consuming and unreliable dosage calculations. In this report, we describe rapid molecular cytogenetic identification of deleted DNA in affected males with the Xp21 contiguous gene syndrome (complex glycerol kinase deficiency, CGKD) and female carriers for this disorder. CGKD deletions involve the genes for glycerol kinase, Duchenne muscular dystrophy, and/or adrenal hypoplasia congenita. We report an improved method for diagnosis of deletions in individuals with CGKD and for identification of female carriers within their families, using fluorescence in situ hybridization (FISH) with a cosmid marker (cosmid 35) within the glycerol kinase gene. When used in combination with an Xq control probe, affected males demonstrate a single signal from the control probe, while female carriers demonstrate a normal chromosome with two signals, as well as a deleted chromosome with a single signal from the control probe. FISH analysis for CGKD provides the advantages of speed and accuracy for evaluation of submicroscopic X-chromosomal deletions, particularly in identification of female carriers. In addition to improving carrier evaluation, FISH will make prenatal diagnosis of CGKD more readily available.

Show, no show and sterilization

The study investigates the factors involved in the decision of a sample of women to break appointments for sterilizations at the Fertility Management Unit of the University of the West Indies. A case control study involved 50 women who did not show up (no-shows) and an equal number who did show up (shows) over the same period. The no-shows had spent a shorter time in their current union than the shows, and some had no children for their partners at the time the appointments were made. Marriage was the single most important event that would encourage the no-shows to consider sterilization in the future. As long as poor women see child bearing as a precondition for financial assistance from spouses, they will hesitate to give up this capability.

The effect of user fees on the utilization of family planning services. A clinical study

A new fee structure was introduced to the Advanced Training and Research in Fertility Management Unit in 1992. The study looked at the effect of the new fees on attendance and the choice of contraceptive methods through an examination of clinical records and a questionnaire survey. There was a decline in attendance of roughly 28 per cent between 1992 and 1993. The decline affected mainly new clients and those who accepted injectables. A reduction in the price of injectables is suggested since the fee for this short-term method is more in line with those charged for long-term and permanent methods.

Syringomyelia and scoliosis: a review of twenty-five pediatric patients

A retrospective review of 25 patients with scoliosis secondary to syringomyelia was conducted. All patients had large syrinxes, but only 10 patients had abnormal neurologic findings, suggesting that subtle neurologic findings in patients with scoliosis should not be underestimated and supporting liberal use of magnetic resonance imaging (MRI). The results of three approaches to the care of these patients were reviewed: passive observation, bracing, and spinal fusion. Curves progressed > or = 5 degrees in patients aged < 10 years who were observed, but in children aged > 10 years, curves progressed > or = 10 degrees. Curves responded well to bracing, but correction was not maintained out of brace for patients with progressive and/or severe curves. Good corrective was achieved safely during operation.

Techniques to enhance extramyocardial collateral blood flow after a cardiomyoplasty

OBJECTIVE

Chronic stimulation of a cardiomyoplasty was combined with low-dose infusion of heparin into the arterial supply of the cardiomyoplasty in order to determine if latissimus-derived collateral blood flow could be further enhanced.

SUMMARY BACKGROUND DATA

Acute and chronic stimulation of a latissimus dorsi cardiomyoplasty increased extramyocardial collateral blood flow to 35 +/- 9% and 27 +/- 5%, respectively, of normal myocardial blood flow.

METHODS

A model of coronary artery disease was created with an ameroid constrictor in goats, and a cardiomyoplasty was performed. Heparin (15 to 50 U/h) was delivered into the left subclavian artery for a period of 4 weeks. Simultaneously, the latissimus dorsi was chronically stimulated at 2 Hz.

RESULTS

Chronic ischemic myocardium received a collateral flow per gram from the skeletal muscle equivalent to 11.8 +/- 5.2% of the blood flow to normal myocardium. The extramyocardial collateral flow correlated with the latissimus muscle flow (r = 0.72).

CONCLUSIONS

Enhancement of extramyocardial collateral flow was not found with heparin treatment. In view of the correlation of extra-coronary collateral flow with latissimus muscle flow, the lack of a heparin effect may have been due to low latissimus blood flow. These results suggest that extramyocardial collateral blood flow to the myocardium is highest if the blood flow to the latissimus dorsi muscle is maintained.

Improving ambulatory oncology nursing practice. An innovative educational approach

To meet the educational needs of ambulatory oncology nurses, an innovative and flexible program was created at a major cancer institute in Canada. Utilizing adult learning principles, standards of nursing practice, and departmental goals, the Clinical Nurse Specialists and Clinical Teachers creatively approached the need for extensive education. Five site specific educational workshops were provided to the nursing staff utilizing a self-directed learning style to capture the varied experiences, educational background, and motivations of the staff. This paper highlights the necessary program elements, implementation of, and evaluation of the educational program.

Race, integration and family planning in Trinidad and Tobago

"The study considered the effect of the integration of the health services on family planning in Trinidad and Tobago. A drop-out study was based on a sample of six clinics, three representing integrated and three clinics that were non-integrated or vertical. Efforts were also made to solicit the views of a sample of drop outs, current acceptors and health-care providers. The study found that there were characteristics of the population from which acceptors were drawn that were more important in explaining utilization than the question of integration or non-integration of the clinics. Many of the problems were organizational and could, with adequate financing, be met by an even higher level of integration."

Spotlight on free beds

What happens in today's hospitals when keeping the faith with donors clashes with fiscal politics? An enterprising assistant attorney general asked that question and turned up some disquieting answers.

Prenatal diagnosis of a craniopharyngioma using ultrasonography and magnetic resonance imaging

We report an infant with a craniopharyngioma which was detected in utero. Maternal uterine ultrasonography, done at 27 weeks because of polyhydramnios, revealed a 4 cm midline mass near the base of the fetal skull. At 31 weeks, magnetic resonance imaging of the maternal abdomen confirmed the presence of a mass in the region of the third ventricle and revealed hydrocephalus. Two days post-partum a computed tomography (CT)-guided needle biopsy of the mass was performed and recovered tissue which was histologically consistent with a craniopharyngioma. The infant's postnatal period was complicated by seizures, which were treated with phenobarbital, and by progressive hydrocephalus, necessitating placement of a ventriculo-peritoneal shunt. He also received therapy for central hypothyroidism and diabetes insipidus. The infant's parents refused permission for attempted resection of the tumour and he died at 8 weeks of age. This represents the second reported case of an antenatally detected craniopharyngioma. Four other cases of different intracranial tumours have been detected in utero using ultrasound, with no reported survivors past 3 days of age. There is a uniformly poor prognosis of such infants, but earlier diagnosis and intervention may change this result.