Search PubMed⌕ Search

Biomedical subjects

P Stanley

Publications and source records attributed to P Stanley.

At least 145 records · Page 8Linked to original sources
PubMed1989

[Arrhythmia disorders after repair of ventricular septal defects. Comparison of atrial and ventricular approaches].

Post-operative disorders of conduction and of ventricular and supraventricular excitability were studied in 50 patients operated upon for ventricular septal defect (VSD). The VSD was approached by right ventriculotomy in 29 patients aged 4.4 +/- 3.1 years at surgery and 15.1 +/- 6.5 years at evaluation. The VSD was closed by the atrial route in 21 patients aged 6.6 +/- 3.9 years at surgery and 12.1 +/- 6.8 years at evaluation. Complete right bundle branch block (CRBB) was significantly more frequent in patients who underwent ventriculotomy (62 p. 100 vs 33 p. 100, p less than 0.05), but 2 late complete atrioventricular blocks were observed in patients in whom the atrial route was used. 34 p. 100 of the patients with ventriculotomy and 26.5 p. 100 of those without ventriculotomy had significant ventricular arrhythmias on Holter recordings (greater than or equal to Lown's grade 2, p = NS). The occurrence of ventricular arrhythmias in the patient population as a whole increased significantly with age at surgery and age at evaluation (p less than 0.05); this increase was also noted in each group (p = 0.06). Pre-operative right ventricular systolic pressure, severity of intraventricular disorders of conduction or duration of extracorporeal circulation and aortic clamping had no influence on the occurrence of ventricular arrhythmias. Disorders of supraventricular excitability were found in 1 patient who had ventriculotomy and in 2 patients whose VSD was corrected by the atrial route. No sinus dysfunction was observed. It is concluded that the ventricular approach of VSD significantly increases the occurrence of post-operative CRBB.(ABSTRACT TRUNCATED AT 250 WORDS)

Arrhythmias, Cardiac↗
PubMed1989

[The Fontan operation in tricuspid atresia. Effect of age, shunt and type of atrial pulmonary connection in tricuspid atresia].

Between 1977 and 1988, 20 patients underwent the Fontan operation. Their age ranged from 4 to 24 years (mean 11 years). The basic disease was tricuspid atresia with ventriculo arterial concordance and right ventricular hypoplasia. Pulmonary stenosis was present in 16 patients. Twenty-eight palliative procedures had been performed previously in the group of patients presenting some forms of pulmonary stenosis. In 2 cases a non-valved conduit has been used for correction, in a third case a valve conduit was utilised, and in a fourth case a right atrioventricular connection was carried out. In the remaining 16 patients, a wide posterior connection between the right atrium and the pulmonary arteries was performed. There were 2 early deaths (10%), and 2 late deaths (10%). After a follow-up ranging from 6 months to 11 years, all survivors are in a satisfying functional condition. We think that a wide unrestricting atriopulmonary anastomosis is mainly responsible for those good functional results. Age at operation has not influenced the results. Previous and long standing shunts may be responsible for immediate and late postoperate cardiac failure. Consequently, we now prefer an earlier corrective procedure, particularly when the patient has a patent systemic pulmonary shunt.

Adolescent↗
PubMed1988

The LEC11 Chinese hamster ovary mutant synthesizes N-linked carbohydrates containing sialylated, fucosylated lactosamine units. Analysis by one- and two-dimensional 1H NMR spectroscopy.

Glycoproteins synthesized by the Chinese hamster ovary cell mutants LEC11 and LEC12 carry the Lex determinant (Gal beta 1,4(Fuc alpha 1,3)GlcNAc), while those synthesized by LEC11 cells also carry the sialyl-Lex determinant (NeuAc alpha 2,3Gal beta 1,4(Fuc alpha 1,3)GlcNAc), and both mutants have been shown to possess a distinct alpha(1,3)-fucosyltransferase of the appropriate specificity to synthesize these determinants (Campbell, C., and Stanley, P. (1983) Cell 35, 303-309; Campbell, C., and Stanley, P. (1984), J. Biol. Chem. 259, 11208-11214; Howard, D. R., Fukuda, M., Fukuda, M. N., and Stanley, P. (1987) J. Biol. Chem. 262, 16830-16837). The LEC11 cells therefore provide a source of carbohydrates terminating in sialylated, fucosylated lactosamine, a relatively rare structure not previously characterized by 1H NMR spectroscopy when in association with an N-linked carbohydrate. In this paper we use a monoclonal antibody specific for Lex to show that the G glycoprotein of vesicular stomatitis virus (VSV) grown in LEC11 and LEC12 cells possesses the Lex determinant and that G from LEC11/VSV also possesses sialylated Lex. Biantennary carbohydrates purified from LEC11/VSV and LEC12/VSV were therefore used to examine the effects on the 1H NMR spectrum of the presence of alpha(1,3)-fucose residues on sialylated and unsialylated lactosamine units. Comparisons of one-dimensional spectra obtained at 500 MHz from LEC11/VSV and LEC12/VSV glycopeptides before and after neuraminidase treatment with spectra of biantennary carbohydrates lacking alpha(1,3)-fucose allowed the assignment of several new resonances. Resolution of certain signals and determinations of coupling constants were achieved by two-dimensional correlation spectroscopy (COSY) at 400 MHz and allowed the assignment of several more resonances in the one-dimensional spectrum.

Amino Sugars↗
PubMed1988

Reconsideration of the anatomy of sling left pulmonary artery: the association of one form with bridging bronchus and imperforate anus. Anatomic and diagnostic aspects.

In sling (retrotracheal) left pulmonary artery (SLPA), the tracheobronchial pattern is generally considered basically normal. Analysis of dissected specimens and/or bronchograms and other preparations from five studied and 32 reported patients suggests that there are two different forms of SLPA: (1) types 1A and B, with normal TB pattern [with (A) or without (B) a right pre-eparterial (tracheal bronchus)], and the aberrant left pulmonary artery causing TB compression. The tracheal bifurcation in type 1 SLPA is usually demonstrable at the fourth to fifth thoracic vertebral level; (2A) SLPA type 2A, with bridging bronchus (BB), in which condition the right main bronchus supplies the right upper lobe, but the bronchus supplying the right middle and lower lobes (the bridging bronchus) arises from the left main bronchus (LMB), posterior to which the SLPA courses; (2B) SLPA type 2B, with absence of the right bronchial tree, and the right lung (usually hypoplastic) supplied by a BB from the LMB, posterior to which the SLPA courses. SLPA types 2A and B have in common varying degrees of tracheal stenosis with abnormal cartilage rings and absent tracheal pars membranacea, abnormally low tracheal "bifurcation" (pseudocarina) at average level T6, increased bronchial angles with "inverted T" pattern, and lower level of anterior esophageal indentation by the SLPA than SLPA type 1. Imperforate anus occurred in 8/58 (14%) of patients with SLPA types 2A or B, but possibly in none with SLPA type 1. SLPA type 2 is the predominant form of SLPA, with the incidence of type 2B being twice that of type 2A.(ABSTRACT TRUNCATED AT 250 WORDS)

Abnormalities, Multiple↗
PubMed1988

The incidence and distribution of spinal metastases in children with posterior fossa medulloblastomas.

Myelography was performed postoperatively in 34 children with posterior fossa medulloblastomas. In 15 patients, there was myelographic evidence of intraspinal spread. This was more common in younger patients. The spread varied from a single nodule to extensive disease with spinal block. The lumbosacral canal was affected most often. Three patients with positive myelograms had negative cerebrospinal fluid cytology. Only one patient had symptoms referrable to the spine.

Adolescent↗
PubMed1988

Outpatient performance of invasive radiologic procedures in pediatric patients.

A retrospective review was done of the outcomes of 102 invasive radiologic procedures--including myelography, angiography and needle aspiration biopsy--performed on an outpatient basis in 94 pediatric patients. Four children had complications requiring visits to their physicians, but no patients required hospitalization after the procedure. With appropriate patient selection, invasive studies performed on an outpatient basis in infants, children, and adolescents are safe.

Adolescent↗
PubMed1988

Primary liver tumors in children: comparison of CT and MR imaging.

A prospective study was performed at two institutions to determine the role of magnetic resonance (MR) imaging in the evaluation of primary pediatric liver tumors. The study compared the usefulness of MR imaging and computed tomography (CT) in providing a correct diagnosis, assessing resectability, and determining tumor recurrence in 23 children with liver tumors. The information obtained with both modalities was correlated with surgical data. The results indicate that the accuracy of MR imaging in helping to differentiate benign from malignant lesions is high and identical to that of CT, but not good enough to obviate surgical diagnosis. While all five hepatocellular carcinomas were correctly diagnosed preoperatively with both modalities, neither CT nor MR imaging could help differentiate these carcinomas from aggressive hepatoblastoma or primary hepatic lymphoma. MR imaging helped correctly predict tumor resectability in all 18 children with malignant hepatic tumors; in one, exact tumor extension was misjudged with CT. Postoperative MR studies suggested tumor recurrence in three children who had unremarkable CT examinations. Second-look surgery showed recurrent tumor in two and fibrosis with chronic inflammation at the surgical margin in the third child.

Adolescent↗
PubMed1988

Implantation of a permanent pacemaker in a premature infant.

In March 1984 we implanted a permanent, dual-chambered pacemaker in a 2.1-kg premature male infant suffering from congenital atrioventricular block, with an atrial rate of 170 beats per minute, a ventricular rate of 40 beats per minute, and ectopic ventricular escape beats. Through a left anterolateral thoracotomy, we implanted electrodes on the left atrium and left ventricle; through a second incision, in the left flank, we gained access to the retroperitoneal space by finger dissection. The electrodes were then guided through the diaphragmatic sulcus into the retroperitoneal space for attachment to a dual-chambered pacemaker permanently placed in the lumbar region. Our patient was discharged in good condition 23 days after operation and continues, despite some difficulties in establishing optimal pacemaker settings, to enjoy excellent clinical status 55 months after implantation, having moved progressively through pacemaker settings for VVI, DVI, and DDD modes, as his heart has improved. To our knowledge, this is the smallest and first-reported premature infant to be treated successfully for complete heart block with a permanent, physiologic pacemaker. In this surgical procedure, use of epicardial leads decreases the prospect of venous or intracardiac thrombosis; use of long leads situated partly in the chest and partly in the retroperitoneal cavity permits stretching as the child grows; and use of the relatively large peritoneal cavity for placement of the stimulator both protects the unit and permits unimpeded diaphragmatic movement, even in a very small infant. Implantation of this larger, permanent pacemaker, as an alternative to the usual ventricular-demand stimulating electrode, both avoids reoperation and permits flexibility in programming, to meet the changing needs of the growing patient.

Journal Article↗
PubMed1988

[Cardiac pacemakers in children. 15 years' experience].

Between 1971 and 1986, 85 pacemakers were implanted at the St Justine Hospital, Montreal, in 57 young patients (25 girls, 32 boys) then aged from one day to 23 years (mean 10.3 years). The patients were followed up for periods ranging from 15 days to 13.5 years (mean 4.5 years); 119 epicardial electrodes were positioned by thoracotomy in 52 patients and by sternotomy in 5 patients; the 85 pacemaker cases were placed in the left retroperitoneal cavity. The pacemakers were programmed in modes VVI (28), AAI (1) and DDD (28). The indications for pacemaker implantation were: complete atrioventricular block in 39 cases (postoperative 16, congenital 22, acquired 1), sinus node disease in 17 cases (postoperative 13, cardiomyopathy 3, normal heart 1) and Romano-Ward syndrome in 1 case. Operated heart diseases which required pacemaker implantation were: D-transposition of the great arteries in 17 cases (complete atrioventricular block 7, sinus node disease 10), tricuspid valve atresia in 3 cases (sinus node disease 3) and tetralogy of Fallot in 3 cases (complete atrioventricular block 3). Twenty-four patients underwent a total of 33 reoperations: 21 changes of battery, 12 changes of electrodes (6 for fibrosis, 6 for breakage). Only one patient developed infection of the pacemaker case. Altogether, the incidence of complications (infection and/or breakage) was low in this series, regardless of the pacing mode. Pacing in children is now an acceptable treatment with low risk provided the indications are well selected.

Adolescent↗
PubMed1988

Cardiac rejection following transplantation in dogs: transmural myocardial blood flow changes.

In cardiac allografts acute rejection produces deleterious effects on blood flow adjustments. In order to differentiate the role of rejection over that of denervation cardiac denervated and cardiac transplanted dogs were compared. A canine model of orthotopic cardiac transplantation was utilized. Electronic devices were implanted for chronic hemodynamic studies. Regional myocardial blood flow distribution was assessed by radioactive microspheres (15 micron in diameter). Studies were carried out when animals had fully recovered (two to three days postoperatively), then in the 'early rejection' stage (five to six days post transplant) and in the 'severe rejection' stage (24 h before death). No significant difference in hemodynamic data or blood flow values were observed between groups in the recovery stage. In the denervated group, adequate cardiac function and myocardial blood perfusion was maintained throughout the study. In the transplanted group, significant loss of function was observed at the severe rejection stage. This was combined with significant decrement in blood flow to all areas of the myocardium. No selective area of underperfusion nor an early reduction in total blood flow could be observed. This study indicates that within cardiac rejection there is a parallel impairment in function and transmural myocardial blood flow which is unrelated to denervation or interruption of lymphatics.

Animals↗
PubMed1987

The GDP-fucose:N-acetylglucosaminide 3-alpha-L-fucosyltransferases of LEC11 and LEC12 Chinese hamster ovary mutants exhibit novel specificities for glycolipid substrates.

Previous studies have shown that the GDP-fucose:N-acetylglucosaminide 3-alpha-L-fucosyltransferase (alpha (1,3) fucosyltransferase (Fuc-T)) activities expressed by the Chinese hamster ovary cell mutants LEC11 (Fuc-TI) and LEC12 (Fuc-TII) are different enzymes and indicated that Fuc-TI might act on sialylated lactosamine sequences (Campbell, C., and Stanley, P. (1984) J. Biol. Chem. 259, 11208-11214). In this paper we show that CSLEX-1, a monoclonal antibody specific for NeuNac alpha (2,3)Gal beta (1,4)(Fuc alpha (1,3))GlcNAc beta 1 sequences, bound to LEC11 cells but not to LEC12 cells. Direct evidence that Fuc-TI could act on sialylated substrates was sought with a series of glycolipid acceptors. Optimal assay conditions in crude cell extracts were determined with nLc4, a glycolipid which accepted fucose with both Fuc-TI and Fuc-TII to generate the Lex antigenic determinant. The two enzymes differed in their detergent sensitivities, pH optima, Mn2+ requirements, and apparent Km values for nLc4. When sialylated glycolipids were examined as substrates, Fuc-TI added fucose to IV3NeuNAcnLc4 but not to IV6NeuNAcnLc4, whereas Fuc-TII was unable to utilize either glycolipid as a substrate. Further studies showed that Fuc-TI and Fuc-TII possess novel specificities for glycolipids containing two lactosamine sequences as potential fucose acceptors. Fuc-TI exhibited good activities with VI3NeuNAcnLc6 and VI6NeuNAcnLc6 whereas Fuc-TII had very low activity with both substrates. Glycosidase digestions of the labeled products showed that Fuc-TI added fucose primarily to the internal N-acetylglucosamine of both glycolipids. The same preference for the internal N-acetylglucosamine was shown by Fuc-TI when nLc6 was the acceptor. In contrast, Fuc-TII preferred to transfer fucose to the external acceptor site of nLc6, consistent with the low activities of Fuc-TII with sialylated nLc6 derivatives. Thus the two enzymes preferentially add fucose to different N-acetylglucosamines in the same substrate, nLc6. This indicates that the biosynthetic pathway for fucosylation of polylactosamine sequences in glycolipids and glycoproteins will vary depending upon the particular alpha (1,3)fucosyltransferase present.

Animals↗
PubMed1987

Renal artery stenosis in pediatric transplant recipients.

From 1967 through 1985, 400 cadaveric transplants were performed at Children Hospital of Los Angeles. Of these 400, 31 were later identified as having renal artery stenosis. No live related graft developed RAS. Of the 31 grafts, 11 were from donors less than 2 years of age. The major feature suggesting stenosis was hypertension; either persistent or a sudden exacerbation often associated with hypertensive encephalopathy. In individuals with hypertension without obvious cause, renal angiography should be promptly conducted under controlled conditions to avoid complications. The stenotic lesion involved 13 end-to-end and 19 end-to-side arterial anastomoses. Surgery for revascularization of RAS was performed in 21 of 31 with success or improvement in 14, no change in 2, and graft loss in 5. Percutaneous transluminal angioplasty was performed in 4. Two were unsuccessful, 1 was successful and 1 graft was lost. The 7 remaining patients were treated medically.

Adolescent↗
PubMed1987

Two unusual duplication anomalies of the urinary tract: use of percutaneous urography.

We performed suprapubic percutaneous urography in two patients to diagnose unusual duplication anomalies of the urinary tract, since preoperative diagnosis was unclear after routine noninvasive studies. In both patients standard suprapubic puncture technique was employed. The procedure was used to confirm the diagnosis of duplication of the bladder in one case and to establish the site of origin of a ureterocele in the other. The technique employed in suprapubic cystography may be extended to the diagnosis of unusual cystic abnormalities in the pelvis that may be of urinary tract origin.

Child, Preschool↗