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D Berlin

Publications and source records attributed to D Berlin.

11 recordsLinked to original sources
PubMed2003

Clonidine improves postprandial baroreflex control in familial dysautonomia.

BACKGROUND: Patients with familial dysautonomia (FD) frequently experience hypertensive crises after gastrostomy feeding. The central alpha2-agonist clonidine attenuates feeding-induced crises. The aim of this study was to assess the effect of clonidine on cardiovascular autonomic modulation and particularly baroreflex sensitivity in familial dysautonomia after gastrostomy feeding. MATERIAL AND METHODS: In nine patients, we monitored the RR-interval and systolic blood pressure at supine rest before (baseline 1) and after gastrostomy feeding (GF1). One day later, recordings were repeated after clonidine intake (baseline 2, GF2). We determined spectral powers of RR-interval and systolic blood pressure in the low- (LF) and high-frequency range (HF). Sympathovagal balance was determined from the LF/HF ratio of RR-interval. Baroreflex sensitivity was assessed from the alpha-index of systolic blood pressure and RR-interval. RESULTS: Gastrostomy feeding decreased RR-interval, while systolic blood pressure remained stable. Clonidine induced higher RR-intervals before and after gastrostomy feeding but decreased systolic blood pressure at baseline only. Gastrostomy feeding decreased HF-power of RR-interval significantly without clonidine, but only slightly after premedication. Clonidine increased the HF-power of RR-interval slightly at baseline and significantly after gastrostomy feeding. Gastrostomy feeding increased the LF/HF ratio without clonidine only. Clonidine decreased the LF/HF ratio at baseline and after gastrostomy feeding. Gastrostomy feeding did not change baroreflex sensitivity, but baroreflex sensitivity was higher at visit 2 than visit 1. CONCLUSIONS: In familial dysautonomia, clonidine augments baroreflex sensitivity and parasympathetic modulation. The resulting cardiovascular stabilization might attenuate feeding-induced crises.

Adolescent↗
PubMed1999

Ventricular tachycardia in an adolescent with arrhythmogenic right ventricular dysplasia.

We report the case of an adolescent boy with exertional syncope and ventricular tachycardia caused by arrhythmogenic right ventricular dysplasia. Diagnosis was determined by transthoracic echocardiography and definitive management with an automatic internal cardiac defibrillator. Emergency physicians must be aware of this serious but treatable cause of adolescent exertional syncope.

Adolescent↗
PubMed1997

A murine model for human cord blood transplantation: near-term fetal and neonatal peripheral blood cells can achieve long-term bone marrow engraftment in sublethally irradiated adult recipients.

The purposes of the research reported here were first to explore a murine model for human placental and umbilical cord blood transplantation and second to evaluate the engraftment ability of ex vivo cultured hematopoietic cells. Murine near-term fetal and neonatal peripheral blood (FNPB) cells, genetically marked with the human multiple drug resistance transgene (MDR1) were used for syngeneic transplants into sublethally irradiated adult mice. Donor cells were transplanted either fresh and untreated, or after ex vivo culture in the presence of the hematopoietic growth factors recombinant murine stem cell factor, recombinant human interleukin-3 (rHu IL-3), and rHu IL-6, in a liquid culture system. To evaluate, count, and characterize FNPB progenitor cell-derived colonies, neonatal mouse mononuclear cells were cultured directly in methylcellulose with growth factors. To assess their ex vivo expansion ability, FNPB mononuclear cells were first cultured in liquid medium for 3 to 8 days and then transferred to semisolid assay plates. Evaluation of the cell counts after liquid culture showed a 1.4- to 11.6-fold increase, and the numbers of colonies observed in methylcellulose were similar to those produced by fresh FNPB cells. Donor-type engraftment was demonstrated by polymerase chain reaction (PCR) amplification of the human MDR1 transgene in the peripheral blood of all surviving animals (5 of 7 recipients of the fresh, and 3 of 8 recipients of the ex vivo-cultured cells) 2 to 4 months after transplantation. The proportion of donor leukocytes in the peripheral blood of the recipients (chimerism) was evaluated using fluorescence in situ hybridization (FISH) analysis 4 to 6 months after transplantation and ranged from 2% to 26%. In addition, bone marrow cultures were obtained from two recipient animals: one had received fresh-untreated cells and was evaluated 8 months after transplant, the other had received ex vivo cultured cells and was tested 14 months after grafting. The derived hematopoietic colonies were tested by PCR and the transgene was detected, conclusively proving long-term engraftment of donor cells. These results indicate that FNPB transplants can be successfully performed in sublethally irradiated mice with and without ex vivo culture. Long-term donor-type engraftment with sustained chimerism has been demonstrated. Thus, murine neonatal blood grafts can be used as an animal model for cord blood transplantation for gene therapy studies where complete myeloablation is not desirable and partial replacement of defective marrow may be sufficient. Furthermore, the possibility of numerically expanding hematopoietic progenitor cells contained in neonatal blood without affecting their engraftment ability could facilitate use of cord blood grafts in adult recipients.

Animals↗
PubMed1996

Pattern of plasma levels of catecholamines in familial dysautonomia.

This report extends previous investigations of endogenous catecholamine levels in patients with orthostatic hypotension due to familial dysautonomia (FD), to define better the neurochemical phenotype and elucidate possible pathophysiological mechanisms. Ten FD patients (age 26.1 +/- 2.6 (SEM) years) and eight control subjects (age 29.5 +/- 3.7 years) were studied. Heart rate, blood pressure and venous blood samples were obtained while supine and after 5 min in the upright position. Plasma levels of dihydroxyphenylalanine (DOPA), noradrenaline (NA), adrenaline (A), dopamine (DA), dihydroxyphenylglycol (DHPG) and dihydroxyphenylacetic acid (DOPAC) were measured. When supine, the FD group had greater NA and DOPA levels, and lower DHPG levels. Plasma NA did not increase with erect posture in FD patients. Individual FD mean blood pressures were correlated positively with plasma NA levels when supine and with plasma DA and DOPAC when upright. In FD, DOPA:DHPG ratios were above the range found in normal subjects or that reported in patients with acquired forms of dysautonomia regardless of posture, whereas DOPAC:DHPG ratios remained normal. Thus FD patients have a characteristic neurochemical pattern which probably reflects either decreased vesicular storage of catecholamines or limited oxidative deamination despite normal or increased tyrosine hydroxylation.

Adolescent↗
PubMed1982

Surgical approaches to Haglund's disease.

The principle objective of this paper is to discuss the various surgical approaches and techniques utilized in excision of the prominent posterior-superior calcaneal exostosis.

Achilles Tendon↗
PubMedDate not supplied

Electrocardiographic measures and heart rate variability in patients with familial dysautonomia.

Cardiovascular abnormalities are prominent in the genetic disorder, familial dysautonomia (FD). To determine if autonomic dysfunction involves cardiac, as well as peripheral vascular integrity, noninvasive tests were performed in 10 FD patients and 8 healthy control subjects while supine and at 90 degrees tilt. Simultaneous blood pressure (BP) and heart rate (HR) and QTc were obtained, while performing signal-averaged electrocardiography (SAECG) and heart rate variability (HRV). FD subjects were tested on 2 separate days, before and 1 h after oral fludrocortisone or midodrine; controls were tested once without medication. With tilt, all FD subjects decreased mean BP > or = 24 mm Hg by 5 min. On SAECG, 70% of supine FD subjects had a prolonged tQRS; only 2 FD subjects shortened tQRS with tilt. The QTc interval was prolonged (> 440 ms) in 2 supine FD subjects; with tilt, the QTc prolonged in a third. Frequency domain analysis of HRV revealed that mid (MF) and high frequency band areas were significantly decreased when supine, but not when upright. On time domain analysis, the pNN50 was significantly decreased in FD subjects (8.9 +/- 1.7 vs. 17.7 +/- 3.6%, p < 0.01). Fludrocortisone lowered supine BP and HR and increased supine MF area. Midodrine raised supine and erect BP, lowered erect HR, and shortened erect QTc. Although all FD subjects have abnormal orthostatic BP and HR responses, cardiac tone, as assessed by electrocardiographic and HRV responses, varies. Prolongation of the tQRS appears to be a sensitive but not specific indicator of autonomic dysfunction. QTc prolongation may indicate more extensive sympathetic dysfunction. HRV data suggest some FD patients have abnormalities in parasympathetic, as well as sympathetic, cardiac tone.

Adolescent↗