Search PubMed⌕ Search

Biomedical subjects

J Segal

Publications and source records attributed to J Segal.

At least 19 recordsLinked to original sources

Developmental outcome of school-age children born to mothers with heroin dependency: importance of environmental factors.

Development of children aged 5 to 12 years born to mothers with heroin dependency raised at home or adopted was studied in comparison with: (1) children with environmental deprivation alone (i.e. low parental socioeconomic status [SES] and evidence of neglect), (2) children born to fathers with heroin dependency fathers, and (3) control individuals of average SES. One hundred and sixty children (84 males and 76 females; average age at examination 8 years) were evaluated between 1998 and 1999. All were attending mainstream schools. All participants were examined by a paediatrician and a psychologist using standard neurological and psychological age-appropriate tests, as well as tests and questionnaires to assess learning ability and attention span. The Conners and Achenbach questionnaires and the Pollack Taper test were used to assess possible presence of attention-deficit-hyperactivity disorder (ADHD). Mothers were assessed for ADHD using Wender's questionnaire. Children born to parents with heroin dependency raised at home and those of low SES exhibited intellectual impairment both on verbal and performance skills. They also had impaired reading and arithmetic skills. Children born to mothers with heroin dependency but who were adopted at a young age had normal intellectual and learning abilities, except for some reduced function on the performance Wechsler Intelligence Scale for Children-Revised. We found a high rate of ADHD among all children born to parents with heroin dependency, including those adopted, as well as in children with low parental SES. The highest rate of ADHD was in children born to mothers with heroin dependency raised at home, being twice that observed in the other groups. Mothers of these groups of children also had a high rate of ADHD.

Adult↗

Effect of imposed inflation time on respiratory frequency and hyperinflation in patients with chronic obstructive pulmonary disease.

Decreases in ventilator inflation time (TI,vent) can cause tachypnea, probably as a response to lung inflation. The response may differ in chronic obstructive pulmonary disease (COPD) because time-constant inhomogeneities could foster overdistention of some lung units during early inflation, causing neural inspiratory time to be shorter than in healthy subjects. We tested the hypothesis that a decrease in TI,vent causes tachypnea, prolongation of exhalation, and a decrease in intrinsic positive end-expiratory pressure (PEEP(i)). Ten patients with stable COPD received assist-control ventilation through a mouthpiece. Decreases in TI,vent, achieved through increases in flow from 30 to 90 L/min, increased frequency, from 16.1 +/- 1.0 (SE) to 20.8 +/- 1.5 breaths/min (p < 0.001), time for exhalation, from 2.1 +/- 0.2 to 2.3 +/- 0.2 s (p < 0.025), and decreased PEEP(i), from 7.0 +/- 1.3 to 6.4 +/- 1.1 cm H(2)O (p < 0.01). Decreases in TI,vent, achieved by decreasing inspiratory pause from 2 to 0 s, increased frequency, from 12.9 +/- 0.8 to 18.1 +/- 1.6 breaths/min (p < 0.001), time for exhalation, from 2.0 +/- 0.2 to 2.6 +/- 0.3 s (p < 0.001), and decreased PEEP(i), from 6.4 +/- 1.1 to 5.5 +/- 0.9 cm H(2)O (p < 0.01). In both experiments, decreases in TI,vent reduced inspiratory effort (p < 0.01). In conclusion, strategies to reduce TI,vent in patients with COPD caused tachypnea, yet prolonged the time for exhalation with consequent decrease in PEEP(i).

Aged↗

N-terminal fatty-acylation of sonic hedgehog enhances the induction of rodent ventral forebrain neurons.

The adult basal ganglia arise from the medial and lateral ganglionic eminences, morphologically distinct structures found in the embryonic telencephalon. We have previously shown that temporal changes in sonic hedgehog (Shh) responsiveness determine the sequential induction of embryonic neurons that populate the medial and lateral ganglionic eminences. In this report, we show that Shh-mediated differentiation of neurons that populate the lateral ganglionic eminence express different combinations of the homeobox-containing transcription factors Dlx, Mash1 and Islet 1/2. Furthermore, we show that N-terminal fatty-acylation of Shh significantly enhances its ability to induce the differentiation of rat E11 telencephalic neurons expressing Dlx, Islet 1/2 or Mash1. Recent evidence indicates that in utero injection of the E9.5 mouse forebrain with retroviruses encoding wild-type Shh induces the ectopic expression of Dlx2 and severe deformities in the brain. In this report, we show that Shh containing a mutation at the site of acylation prevents either of these phenotypes. These results suggest that N-terminal fatty-acylation of Shh may play an important role in Shh-dependent signaling during rodent ventral forebrain formation.

Animals↗

Emerging options in the treatment of bipolar disorders.

Bipolar disorder is a common and severe condition, and has a clinical outcome that is frequently sub-optimal. Only a small number of therapeutic options are currently available for the disorder. A growing range of novel therapeutic options for the treatment of bipolar disorder are under investigation. These include the anticonvulsants, atypical antipsychotics and options such as the omega-3 fatty acids and transcranial magnetic stimulation. Of the anticonvulsants, lamotrigine is currently the agent for which the greatest amount of controlled clinical data is accumulating, particularly in the depressed and rapid cycling phases of the illness. Olanzapine is currently the atypical antipsychotic with the largest body of evidence in mania, although data is emerging on other atypical antipsychotics including risperidone and ziprasidone. Data regarding the atypical agents in other phases of the illness are awaited. The options available for this difficult to treat condition is increasing with the new range of agents.

Anticonvulsants↗

Coronary angioplasty performed using the FullFlow mechanical dilatation-perfusion catheter: initial animal experience.

We report our initial experience with an animal model, using a new mechanical catheter-based dilatation system, the FullFlow (FF) catheter. The primary purpose of this study was to compare coronary flow achieved using the FF perfusion catheter and a traditional balloon angioplasty perfusion catheter. Baseline average peak velocity (APV) measurements were obtained using the FloWire Doppler guide wire. Either a Surpass Perfusion balloon (PB) or an FF catheter was advanced to a coronary segment. Doppler measurements were made before, during, and after full device expansion. Simultaneous heart rate, EKG, and blood pressure readings were recorded. Significant 36.1% and 29% reductions in mean APV were found for PB when comparing baseline to device-up measurements and when comparing device-down to device-up measurements, respectively. In contrast, significant 12.2% and 18.5% increases were seen in mean APV for the FF. No significant differences were found in heart rate, systolic blood pressure, diastolic blood pressure, or ST-segment changes. The FF system produces superior downstream coronary perfusion with side-branch coronary patency compared with results using a contemporary perfusion balloon angioplasty catheter.

Angioplasty, Balloon, Coronary↗

Tissue factor activity in patients with systemic lupus erythematosus: association with disease activity.

OBJECTIVE: Tissue factor (TF) is the major intrinsic initiator of clotting. TF expression on monocytes has been associated with high titers of anticardiolipin antibodies (aCL) in patients with antiphospholipid syndrome (APS) with thrombosis. We investigated the influence of clinical factors on TF activity in blood from patients with systemic lupus erythematosus (SLE) and examined the relationship between aCL and TF. METHODS: In this cross sectional study, consecutive patients with SLE from one rheumatology clinic gave blood samples for measurement of TF activity, aCL, and Russell viper venom time. We assessed disease activity by measuring sedimentation rate, anti-dsDNA, and complement components C3 and C4, and measured clinical indices. Associations were investigated with the Wilcoxon rank-sum test and linear regression. RESULTS: Sixty-nine patients contributed blood samples. The median age was 38 years, and 10 of the SLE patients had a history of thrombosis. Patients with active arthritis had TF activity 1.3 times that in patients without arthritis (p = 0.028). Users of nonsteroidal antiinflammatory drugs (NSAID) had TF activity significantly lower than nonusers (p = 0.010). Patients with previous thrombosis had TF activity significantly lower than patients without thrombosis (p < 0.001). Overall, aCL and TF activity were not associated when we adjusted for these clinical factors. CONCLUSION: Arthritis, previous thrombosis, and use of NSAID significantly modified TF activity in patients with SLE. Unlike previous reports, we found no association between aCL titer and TF activity, which may be due to our adjusting for other important clinical factors.

Adolescent↗

An 18-year experience with the umbrella graft in rhinoplasty.

Inadequate nasal tip projection is the most common problem of primary and secondary rhinoplasty. Inadequate nasal tip projection with inadequate septal support requires an umbrella graft. The umbrella graft consists of a vertical cartilaginous strut between the medial crura and a horizontal onlay graft overlying the alar domes. The umbrella graft supports the nasal tip pyramid and reestablishes nasal tip projection. The statistics included in this report involve 1252 cases from 1986 to 1996, and it was discovered that 22 percent of the patients required an umbrella graft. Most of these patients had secondary rhinoplasties. The revision rate was 5 percent; the most common complication was cartilaginous show. Cartilage graft loss or significant absorption was not observed. A closed rhinoplasty approach with autologous tissue to reconstruct nasal tip projection was used. The umbrella graft technique is time proven, successful, and reproducible.

Adolescent↗

Prevalence of spinal disc disease among interventional cardiologists.

A suspected, but undocumented, excess of axial skeletal disease among interventional cardiologists (possibly a consequence of lead apron use) was investigated by comparing questionnaire responses from cardiologists, orthopedic surgeons, and rheumatologists (n = 714). Cardiologists reported more neck and back pain, more subsequent time lost from work, and a higher incidence of cervical disc herniations, as well as multiple level disc disease (all p <0.01): "interventionalist's disc disease" is a confirmed entity.

Adult↗

Suppressed cell-mediated immunity and monocyte and natural killer cell activity following allogeneic immunization of women with spontaneous recurrent abortion.

Spontaneous recurrent abortion (SRA) has been treated by means of immunization with paternal or third-party white blood cells, yet the immunological basis for SRA and for the role of immunization protocols in pregnancy outcome remains controversial. To elucidate this question, nine women with SRA were immunized with paternal mononuclear cells and studied before and 2 weeks after immunization. Seven women who became pregnant gave birth to live newborns. Secretion of the T helper 1 cytokines IL-2 and interferon-gamma by patients, mononuclear cells decreased, while production of IL-10 increased. The levels of natural killer and lymphokine-activated killer cell-mediated cytotoxicity were markedly decreased. Monocyte functions such as secretion of IL-1 alpha, tumor necrosis factor alpha, IL-6, and cytotoxic activity decreased concurrently with elevations in IL-10 and transforming growth factor beta secretion. Production of IL-12, a pivotal regulatory cytokine, decreased. Furthermore, B7/1 expression on patients' mononuclear cells was downregulated. This resulted in a decrease in monocyte costimulatory activity of purified T cells with soluble anti-CD3, paralleled by a decline in allogeneic proliferative responses. These results suggest that the improved pregnancy success rate in women with SRA following immunization may be partly related to suppression of cell-mediated immunity and monocyte and natural killer cell activity.

Abortion, Habitual↗

A four-year experience with laparoscopy in the management of appendicitis.

BACKGROUND: The study was conducted to determine the influences of laparoscopy in the management and outcome of patients with appendicitis. METHODS: A retrospective analysis of 154 consecutive patients who were treated for suspected appendicitis. The pre-operative diagnosis included appendicitis, right lower quadrant pain of unknown etiology, and generalized peritonitis. RESULTS: Laparoscopy was used in 108 patients, including 70 laparoscopic appendectomies (LA) and 31 LAs converted to open appendectomy (OA). Forty-six patients had OA. The average operating time for LA was 74.3 minutes and 48.8 minutes with OA. Postoperative complications for LA (7%) included 1 trochar wound hemorrhage, 2 wound infections, and 2 intra-abdominal sepsis; and for OA (9%) were 1 post-operative intra-abdominal hemorrhage, 4 wound infections, 1 wound dehiscence, and 1 intra-abdominal sepsis. Post-operative stay for LA averaged 2.5 days and for OA averaged 4.5 days (P = .0049). LA patients had a considerably faster return to work and/or normal activity than OA patients (P = .00065). CONCLUSIONS: Laparoscopy influenced the management of 29% of patients presenting with suspected appendicitis. LA resulted in shorter hospitalization and a more rapid return to work and/or normal activity than OA.

Adolescent↗

Acute effect of thyroid hormone in the rat heart: role of calcium.

Several observations provide some clues as to the possible mode of the regulatory action of thyroid hormone (TH) in the heart, indicating delayed action at the level of the nucleus and acute effects on the plasma membrane. Here we present evidence for a direct and rapid stimulatory effect of TH in the intact normal heart. In the isolated perfused rat heart, 3,5,3'-tri-iodothyronine (T3) produced a positive inotropic effect increasing both the left ventricular peak systolic pressure (P) and +dP/dt values, but had no significant effect on heart rate. This effect of T3 was: (1) very rapid in onset (starting after 15 s) and transient, increasing gradually to reach a maximum (80% above control) at about 20 min, and declining progressively 20 to 30 min later; (2) dose-related and biphasic, occurring at physiological concentrations as low as 1 pM (+dP/dt) and 10 pM (P), reaching a maximum at 1 nM, and decreasing at higher concentrations; and (3) thyroid hormone specific, as shown by the effects of several TH analogs (L-T3 > L-thyroxine (T4) = D-T3 > D-T4; 3,3',5'-tri-iodothyronine (rT3), 3,5,-L-di-iodothyronine and DL-thyronine had no effect). The calcium blockers nifedipine and verapamil, at concentrations of 10(-8) - 10(-5) M given before or after the addition of T3 (10(-9) - 10(-6) M), inhibited the T3-induced increase in cardiac inotropic activity in a time- and dose-related fashion. We suggest that the acute effect of TH in the heart is plasma membrane-mediated and calcium-dependent.

Animals↗

Doppler guide wire flow-velocity indexes measured distal to coronary stenoses associated with reversible thallium perfusion defects.

A Doppler guide wire was used to measure phasic coronary blood flow velocity distal to coronary stenoses in 17 symptomatic patients with corresponding positive exercise or adenosine thallium scintigrams. Distal average peak velocity and diastolic/systolic flow-velocity ratio were obtained in 16 vessels with stenoses (55% to 85% diameter stenosis) and a corresponding reversible thallium defect and in 11 control vessels with no stenosis or thallium defect. Coronary flow-velocity reserve was obtained with intracoronary adenosine. Coronary flow reserve (2.3 +/- 0.4 vs 1.2 +/- 0.3, p < 0.01) and diastolic/systolic flow-velocity ratio (1.95 +/- 0.56 vs 1.44 +/- 0.59, p < 0.04) were significantly different between normal vessels and distal to stenoses, respectively. Excellent concordance between distal coronary flow reserve and diastolic/systolic flow-velocity ratio to thallium scintigraphy was noted. A coronary flow reserve of < 1.8 and a diastolic/systolic flow-velocity ratio of < 1.7 predicted a reversible thallium perfusion scintigram (concordance 96% and 88%, respectively). Distal coronary flow velocity indexes may provide an alternative means of physiologic assessment of lesion severity during coronary angiography.

Adenosine↗

Interaction of thyroid hormone and heparin in postischemic myocardial recovery.

BACKGROUND: Triiodothyronine (T3) administration can improve postischemic myocardial recovery. Heparin can interfere with cellular binding of T3. Introduction of heparin into an isolated heart model may interfere with this effect. METHODS: Four groups of 8 rat hearts were placed on a modified Langendorff apparatus. All groups underwent 15 minutes of perfusion with modified Krebs-Henseleit solution (KH), followed by 20 minutes of normothermic global ischemia and 30 minutes of reperfusion. Group I underwent reperfusion with KH. Group II underwent reperfusion with KH and 1 x 10(-6) mol/L of T3. In group III, hearts underwent preischemic perfusion with heparinized KH (1,000 U/L) and reperfusion with KH containing 1 x 10(-6) mol/L of T3 and 1,000 U/L of heparin. In group IV, rats were given heparin at 2,000 IU/kg 30 minutes before sacrifice, and isolated hearts were reperfused with KH and 1 x 10(-6) mol/L of T3. A latex balloon in the left ventricle monitored hemodynamic variables. RESULTS: Left ventricular developed pressure throughout postischemic reperfusion was greater in all the groups receiving T3 when compared with group I. Group II showed significantly greater recovery than either group III (p < 0.05) or group IV (p < 0.05). CONCLUSIONS: Addition of T3 to the reperfusate enhances postischemic myocardial recovery in the isolated heart model, whereas addition of heparin reduces this effect.

Animals↗

Coronary blood flow reserve in acute aortic regurgitation.

OBJECTIVES: This study sought to determine the impact of acute aortic regurgitation on coronary blood flow reserve and phasic epicardial coronary blood flow in closed-chest dogs. BACKGROUND: Hemodynamic changes in acute aortic regurgitation are known to precipitate myocardial ischemia. Coronary blood flow reserve has not been studied in closed-chest experimental preparations with acute aortic regurgitation. METHODS: Graded temporary acute aortic regurgitation was produced in 11 mongrel dogs. Phasic coronary blood flow velocities were measured using a Doppler guide wire. Coronary flow reserve was defined as the ratio of the time average of spectral peak velocity after administration of papaverine to that of the baseline state. RESULTS: Under control conditions (mean [+/- SEM] diastolic blood pressure 82.2 +/- 4.5 mm Hg), coronary flow reserve was 3.51 +/- 0.27 with predominantly diastolic epicardial coronary blood flow. With mild acute aortic regurgitation (diastolic blood pressure 61.8 +/- 3.0 mm Hg), coronary flow reserve decreased to 2.38 +/- 0.27, with an increase in phasic systolic epicardial coronary blood flow. At the onset of moderate acute aortic regurgitation (diastolic blood pressure 42.1 +/- 0.9 mm Hg), coronary flow reserve declined further to 1.46 +/- 0.12, and the phasic systolic epicardial coronary blood flow became more prominent. With severe aortic regurgitation (diastolic blood pressure 29.2 +/- 2.2 mm Hg), coronary flow reserve reached 1.20 +/- 0.05, and the phasic epicardial coronary blood flow pattern was found to be predominantly systolic with retrograde diastolic flow. The ratio of diastolic to systolic pressure-time indexes with severe aortic regurgitation suggested subendocardial underperfusion. CONCLUSIONS: This study demonstrates a marked decline in coronary blood flow reserve and documents a progressive change in the phasic epicardial blood flow to a predominantly systolic pattern with increasing degrees of acute aortic regurgitation.

Animals↗