PubMed Health⌕ Search

Biomedical subjects

L C Graham

Publications and source records attributed to L C Graham.

8 recordsLinked to original sources

The fish endocrine pancreas: review, new data, and future research directions in ontogeny and phylogeny.

The literature on the ontogeny and phylogeny of the endocrine pancreas of ray-finned fishes is summarized since the latest review in fish [Youson, J.H., Al-Mahrouki, A.A., 1999. Review. Ontogenetic and phylogenetic development of the endocrine pancreas (islet organ) in fishes. Gen. Comp. Endocrinol. 116, 303-335]. A basic description and a demonstration of the diversity of the fish islet organ is provided through new immunohistochemical data on islet tissue from a basal teleost, an osteoglossomorph, and a more derived teleost, a perciforme. Unlike the previous review, the present report provides a review and discussion of the utility of sequence data of insulin, somatostatin, and NPY- and glucagon-family peptides in phylogenetic analyses of jawed and jawless fishes. The present study also provides the first comparative analysis of sequences of preprohormones of endocrine peptides from closely related basal teleost species. Some nucleotide and deduced amino acid sequence data for preprosomatostatins (PPSS-I and/or -II) are compared for four species of bonytongues, Osteoglossomorpha, and with PPSSs of the white sucker, Catostomus commersoni, representing Cypriniformes, a more generalized teleost order. Phylogenetic analysis of deduced amino acid sequences of the PPSSs of these species and others from databases indicates good support for the monophyly of Osteoglossomorpha and some support for the present taxonomic grouping of the osteoglossomorphs examined, and also the white sucker. However, PPSS may have limited phylogenetic utility due to the relative short sequence, particularly in resolving relationships among lineages that diverged over a short period of time. Since in the few fish species examined we have just touched the surface in describing the diversity of structure of the islet organ, and likely the nature of the products of its cells, this report promotes the continued study of this organ.

Amino Acid Sequence↗

Molecular cloning of preproinsulin cDNAs from several osteoglossomorphs and a cyprinid.

Several preproinsulin cDNAs were isolated and characterized from four members of the Osteoglossomorpha (an ancient teleost group); Osteoglossum bicirrhosum (arawana), Pantodon buchholzi (butterfly fish), Notopterus chitala (feather fin knife fish), Hiodon alosoides (goldeye) and Gnathonemus petersii (elephantnose). In addition, we isolated and characterized the preproinsulin cDNA from Catostomus commersoni (white sucker, as a representative of a generalized teleost). The comparative analysis of the sequences revealed conservation of the cystine residues known to be involved in the formation of the disulfide bridges, as well as residues involved in the hexamer formation, except for B-17 in the butterfly fish, the arawana and the goldeye. However, the N-terminus of the B-chain was very weakly conserved among the species studied. Residues known to be significant for maintaining receptor-binding conformation and those known to comprise the receptor-binding domain were all conserved, except for a conservative substitution at B13, aspartate substituted glutamate in the arawana, goldeye, butterfly fish and white sucker, and at B16, phenylalanine substituted tyrosine in the elephantnose. Phylogenetic analysis of the sequences revealed a monophyletic grouping of the osteoglossomorphs, and showed that they were not the most basal living teleost. Comparative sequence analysis of preproinsulins among the osteoglossomorphs was useful in assessment of intergroup relationship, relating elephantnose with the feather fin knife fish and the arawana, butterfly fish, and goldeye. This arrangement of species is consistent with relationships based on other more classical parameters, except for the goldeye which was assessed as being sister to all the osteoglossomorphs. The white sucker was grouped with the common carp and both are cyprinids.

Amino Acid Sequence↗

Early detection of cardiac dysfunction: use of the myocardial performance index in patients with anorexia nervosa.

OVERVIEW: Patients with anorexia nervosa have functional cardiac abnormalities secondary to their nutritionally depleted state. These abnormalities include decreased left ventricular (LV) mass and varying degrees of LV systolic dysfunction. Assessment of LV diastolic function and quantitative assessment of right ventricular function are not routinely performed. The myocardial performance index (MPI) is a relatively new, simple, quantitative measure of global myocardial function. The purpose of this study was to evaluate left and right ventricular function in 13 patients with anorexia nervosa with the MPI and compare it to more commonly used echocardiographic measures of ventricular function.

Adolescent↗

Gaining vascular access in pediatric patients: use of the P.D. access Doppler needle.

This article describes our initial experience with the P.D. Access Doppler needle for obtaining vascular access in pediatric patients. Patients were considered for use of the P.D. Access Doppler needle (Escalon Vascular Access, New Berlin, WI) if they had a history of difficult access or body habitus limitations to vascular access. An 18-, a 20-, or a 22-gauge bare needle with an inserted Doppler stylet was utilized. The time from initial subcutaneous entry of the Doppler needle until wire placement into the vessel lumen was recorded. Initial attempts to cannulate were performed with standard Seldinger technique. If attempts with the standard technique were unsuccessful, then P.D. Access was utilized. However, P.D. Access was used primarily in small children for internal jugular vein cannulation or in patients with coarctation who had absent/diminished femoral pulses. P.D. Access cannulation was attempted 39 times (31 patients). Median age is 23 months (range, 1 day to 15 years). Median weight is 10.5 kg (range, 1.7-57 kg). These patients had a mean of two prior cardiac catheterizations and/or surgeries (range, 0-6 procedures). Use of P.D. Access resulted in successful cannulation in 35/39 (90%) attempts. In successful outcomes, the time from initial subcutaneous entry to cannulation is 6.5+/-4.9 min. In unsuccessful outcomes, failure was due to prior hematoma formation, operator inexperience, or prior vessel occlusion. Successful use of P.D. Access shortens the duration of vascular access in difficult pediatric patients. In our cardiac catheterization laboratory, this technique has become the preferred initial entry technique for cannulation of the internal jugular vein in small children. In addition, this technique was particularly useful for femoral artery cannulation in patients with coarctation of the aorta with absent/diminished femoral pulses.

Adolescent↗

Extended end-to-end repair and enlargement of the entire arch in complex coarctation.

BACKGROUND: Treatment of hypoplasia of the entire arch in coarctation is a surgical challenge. The current approaches have technical difficulties, high recurrence rates, and increased morbidity and mortality. METHODS: Over a 14-month period, a combined extended end-to-end repair with patch enlargement of the concavity of the entire arch was performed in 6 neonates and 1 infant. Through a midsternotomy and using cardiopulmonary bypass and hypothermia, extended end-to-end repair was performed initially leaving the proximal anastomosis open. The enlarging polytetrafluoroethylene patch was then sutured starting at the incised descending aorta distal to the extended end-to-end repair and continued retrogradely through the transverse arch to the ascending aorta proximal to the aortic cannulation site. One neonate had a patent ductus arteriosus and another had ventricular septal defect closure. One neonate had arterial switch and 3 had Norwood-type procedures performed with the enlarging patch extended to the pulmonary artery anastomosis. The remaining infant had arch enlargement performed after an arterial switch procedure and extended end-to-end repair. RESULTS: All patients did well and showed no residual gradient up to 1 year follow-up. Two patients successfully had bidirectional Glenn shunt at 9 months of age, and one had closure of residual arterial septal defect at 8 months of age. CONCLUSION: The combined extended end-to-end repair and arch enlargement procedure should minimize recurrence rates because of a tension-free enlargement of the entire aortic arch and elimination of the coarctation ridge and ductile tissues. Combined with the arterial switch and Norwood-type procedures, the approach results in a large neoaorta.

Anastomosis, Surgical↗

Piercing and tattooing in patients with congenital heart disease: patient and physician perspectives.

PURPOSE: The frequency and safety of ear piercing and tattooing were assessed in a group of children, adolescents, and adults with congenital heart disease (CHD). Also, a group of physicians who care for adolescents and adults with CHD were surveyed for opinions and experiences regarding piercing and tattooing. METHODS: An eight-question survey was mailed to 445 patients (181 adults and 264 children) from one center. A different five-question survey was mailed to 176 physician members of the International Society of Adult Congenital Cardiac Disease. RESULTS: The patient survey was completed by 152 of 445 (34%) patients (mean age +/- standard deviation 19.8 +/- 16.2 years; range 0.25-67 years). Eighty-eight of 152 (58%) patients were female. Ear piercing occurred in 65 of 152 (43%) patients (mean age 12.4 +/- 8.7 years; range 0.25-45 years). Prior to piercing, only 4 of 65 (6%) patients took antibiotics, but 15 of 65 (23%) had piercing-related infections. No patient had endocarditis. Infections occurred 1 week to 3 years after piercing. All were local skin infections. Tattoos were placed in 8 of 152 (5%) patients (median age 17.5 years; range 13-56 years). No antibiotic use or infections were reported in patients with tattoos. The physician survey was completed by 118 of 176 (67%) physicians. The majority of physicians did not approve of patients having piercing or tattooing performed. However, 60% of physicians believed that antibiotic prophylaxis is indicated for these procedures. CONCLUSIONS: Despite the opinion of many physicians, most patients do not take antibiotic prophylaxis for piercing and tattooing. Patients apparently do not suffer serious sequelae. The efficacy of standard antibiotic regimes as applied to ear piercing and tattooing requires further study, since these procedures are increasingly popular in modern society.

Adolescent↗