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Biomedical subjects

P Weiss

Publications and source records attributed to P Weiss.

At least 127 records · Page 7Linked to original sources
PubMed1992

Rapid reversal of heart failure in a patient with phaeochromocytoma and catecholamine-induced cardiomyopathy who was treated with captopril.

A patient with a phaeochromocytoma and severe left ventricular heart failure caused by a catecholamine-induced cardiomyopathy is described. The clinical signs of congestive heart failure resolved rapidly on treatment with captopril and myocardial performance became normal within two weeks of medical treatment with captopril for one week and with captopril in combination with phenoxybenzamine for another week.

Acute Disease↗
PubMed1992

Hyposialylated thyroglobulin in a patient with congenital goiter and hypothyroidism.

A large family (14 children) with congenital goiter whose parents are first cousins was studied. Thyroid tissue was obtained, after 125I in vivo labeling, from one of the siblings (JBM). Gel filtration of thyroid proteins indicated that thyroglobulin (Tg) eluted as a single symmetrical peak in the same position as authentic 19S Tg. Gel electrophoresis in a 7.5% sodium dodecyl sulfate-polyacrylamide gel revealed a major band with the same mobility and immunoreactivity as normal 19S Tg. Hydrolysis of the patient's Tg indicated that most of the radioactivity was mono- and diiodotyrosines. The yield of T4 from JBM Tg (26 pmol/mg protein) was 5-fold less than normal thyroid tissue (140 pmol/mg protein) and approximately half of that in thyroid tissue from endemic goiter (51 pmol/mg). Total T3 released from JBM Tg was similar to the other two tissues. When the carbohydrate content of normal and patient Tg was analyzed, there was no differences in glucosamine, galactose or mannose content. However, unlike normal and endemic-goiter Tg, that had a mean sialic acid content of 7.3 and 5.6 micrograms/mg protein, respectively, the sialic acid concentration of the patients Tg was only 0.3 microgram/mg. Sialyltransferase activity was readily demonstrated in homogenate from normal thyroid or endemic goiter, but no sialyltransferase activity was detectable in a homogenate of JBM-thyroid tissue. We conclude that the finding of severely hyposialylated Tg is linked to a defect in iodotyrosine coupling seen in this patient with a possibly abnormal migration of Tg into the follicular lumen.

Carbohydrate Sequence↗
PubMed1992

Influence of different pressure gradients on late clinical outcome after aortic valve replacement.

Late outcome vs. hemodynamic parameters were assessed and compared in a series of 44 patients followed for 10-17 years after aortic valve replacement either with a Starr-Edwards A 1260 (SE) or a Bjork-Shiley 60 degrees (BS) prosthesis. The two groups, 22 patients each, were selected by computer from the data base SG as to be matched for age, sex, underlying lesion, date of implantation, valve size, left ventricular function, and concomitant coronary artery disease. There was no significant difference in mortality and complication rates. Clinical evaluation at a mean of 12.5 +/- 2.2 years postoperatively revealed identical findings of heart size on chest X-rays (CTR 0.50 +/- 0.04 SE vs. 0.50 +/- 0.05 BS) and nearly identical incidence of left ventricular hypertrophy on the ECG (2/22 SE and 1/22 BS). There was a statistically significant difference in Doppler ultrasonic peak pressure gradients between the two valve types (SE 32 +/- 15 mmHg, BS 23 +/- 9 mmHg; p = 0.047), and of fractional shortening on M-mode echocardiograms (SE 30 +/- 9%, BS 37 +/- 8%, p = 0.038), but this was not reflected by a difference in the symptomatic status of the two groups. It is concluded, that in two groups of patients surviving 10-17 years after isolated aortic valve replacement with SE or BS valves, the statistically significant nine mmHg difference in gradient across the two valve types had no effect on long-term clinical outcome.

Aortic Valve↗
PubMed1992

Abbott IMx and serono MAIAclone assays compared for lutropin determinations in urine.

The urinary lutropin (luteinizing hormone; LH) profiles of 20 patients were determined in 10 consecutive urine samples (n = 200) with a manual technique (MAIAclone, Serono; y) and a fully automated (Abbott IMx; x) technique. For 132 single determinations within the range of detection, the regression line was y = 1.39 x - 0.07 (r = 0.85). Retrospective analysis of the LH profiles obtained by the IMx yielded the classification "not pregnant" (negative) in 14 cases, of which 13 were correctly classified; 6 profiles were classified as "pregnant" (positive), which correlated with the clinical findings in 4 cases. Nine of the LH profiles analyzed with the MAIAclone method were classified as negative, which was correct in seven cases. Retrospective analysis of 11 LH profiles established with the MAIAclone assay gave positive results, which agreed with the clinical outcome in three cases. The diagnostic sensitivity of the IMx and MAIAclone methods was 87% and 47%, respectively; diagnostic specificity was 80% and 60%, respectively. In smaller series (< or = 40 samples), the IMx method has considerable advantages over the MAIAclone method in cost and convenience, because standard curves can be stored and assays can be performed as single determinations.

Autoanalysis↗
PubMed1991

[Hemodynamics of various heart valve prostheses].

Modern tilting disc and bileaflet prostheses, and bio-prostheses, perform similarly regarding pressure gradients, discharge coefficient and performance index; however, only bio-prostheses increase their opening area with increasing flow. Ball valve prostheses of the Starr-Edwards type perform less satisfactorily with higher pressure gradients and lower performance indices, which may result in less favorable long-term follow-up. Bio-prostheses show degenerative changes with increasing age which, over a period of 7-10 years, can lead to clinically relevant stenoses necessitating reoperation.

Bioprosthesis↗
PubMed1991

[Are ECG criteria for indications for thrombolysis in acute myocardial infarct defined too narrowly?].

BACKGROUND: Despite the advantages of fibrinolytic therapy in acute myocardial infarction only about 20% of these patients receive this therapy. We studied patients excluded from fibrinolysis to identify subgroups with high mortality, which could derive benefit from more liberal interpretation of the indications for fibrinolytic therapy. METHODS: Retrospective chart review to identify patients with acute myocardial infarction in our coronary care unit 7/88-7/89. All patients received a questionnaire one year after this myocardial infarction. Patients not answering the questionnaire were contacted by phone or the information was sought from their physician. Indications for thrombolysis (with streptokinase or rTPA) were ST elevations of greater than or equal to 2 mm in greater than 2 adjacent leads and the absence of contraindications. RESULTS: In 231/242 (95%) of the identified patients a complete follow-up was obtained, 32% were age greater than 70 years, 30% were admitted greater than 6 h after the beginning of the symptoms, 64% did not fulfil the ECG criteria for thrombolysis, 21% (49/231) received thrombolytic therapy. The mortality after one year was 20.3% in patients not treated with thrombolysis and 8.2% in patients with thrombolysis (difference 12.1%, 95% confidence interval 2.9-21.3%, p = 0.048). Patients with preceding old infarctions (n = 58) fulfilled the ECG criteria for thrombolysis in a significantly smaller proportion (21% vs 41%, p = 0.004). Of all patients 12% were excluded from thrombolytic therapy due to a negative initial ECG and yet developed a Q ware infarction. The one year mortality of patients not given thrombolysis and with a Q wave infarction was 24% (22/93, p = 0.02 as compared to patients with thrombolysis), in patients with non Q wave infarction it was 13% (11/82, p = 0.41) and in patients with ambiguous ECG it was 57% (4/7, p = 0.006). The mortality in patients with a preceding infarction was 31% and significantly higher than in patients with a first infarction (16%, p = 0.049) and in patients receiving thrombolysis (8.2%, p = 0.005). CONCLUSIONS: By excluding patients with acute myocardial infarction from thrombolytic therapy a group with high first year mortality is selected. Most patients are excluded because of an initial ECG not showing enough ischemia to fulfil the criteria for thrombolytic therapy. A prospective study of thrombolytic therapy using less rigid ECG criteria in the subgroups with the highest mortality (patients with preceding myocardial infarction or ambiguous ECG) seems necessary.

Acute Disease↗
PubMed1991

Sialic acid metabolism in sialuria fibroblasts.

Sialuria is a rare inborn error of metabolism caused by excessive synthesis of sialic acid (N-acetylneuraminic acid, NeuAc). Fibroblasts cultured from the three known cases of sialuria contained 70-200-fold increases in soluble sialic acid, but normal concentrations of bound sialic acid. The sialic acid appeared in the cytosolic fraction of the cells on differential centrifugation, and was susceptible to borohydride reduction, suggesting that accumulated sialic acid was in the form of NeuAc and not CMP-NeuAc. In biochemical studies, CMP-NeuAc (50 microM) inhibited the UDP-N-acetylglucosamine (UDP-GlcNAc) 2-epimerase of normal fibroblasts by 84-100%, but inhibited the epimerase from sialuria cells by only 19-31%. Feeding sialuria cells up to 5 mM D-glucosamine for 72 h increased free sialic acid content 20-60%, but normal cells were unaffected by this treatment. Cytidine feeding (5 mM, 72 h) reduced the NeuAc content of sialuria cells, initially 112, 104, and 266 nmol/mg protein, by 63-71 nmol/mg protein; CMP-NeuAc concentrations, initially 4, 2, and 5 nmol/mg protein, increased by 14-33 nmol/mg protein. Consequently, the total cellular content of soluble sialic acid (NeuAc + CMP-NeuAc) was lowered 14-46% by cytidine feeding. The inheritance pattern of sialuria has not been determined. However, cells from both parents of one sialuria patient contained normal concentrations of free sialic acid, and the parental epimerase activity also responded normally to CMP-NeuAc. We conclude that the basic biochemical defect in all known cases of sialuria is a failure of CMP-NeuAc to feedback-inhibit UDP-GlcNAc 2-epimerase and cytidine feeding can lower the intracellular soluble sialic acid concentration of sialuria cells.

Child, Preschool↗
PubMed1991

Timing of invasive procedures in therapy for primary and secondary spontaneous pneumothorax.

Timing of invasive procedures during chest tube therapy in spontaneous pneumothorax is undefined. Evaluation of 115 patients with primary and secondary spontaneous pneumothorax treated with tube thoracostomy revealed nearly maximal healing rates after 48 hours without a relevant increase if drainage was maintained for up to 10 days. In secondary spontaneous pneumothorax, a significantly lower healing rate was observed after 48 hours compared with primary spontaneous pneumothorax (60% vs 82%). Therapeutic success was not predictable by single clinical variables available at admission (eg, age, gender, and smoking habits) nor by their combinations. Recurrence rates were 30% in both primary and secondary spontaneous pneumothorax. Hospital stay averaged 6 days in primary and 15 days in secondary spontaneous pneumothorax. Considering their efficacy and the low incidence of complications, the early use of invasive procedures such as surgical pleurectomy, after 48 hours of persistent gas leaking, seems justified. Shorter in-patient care and lower recurrence rates may result.

Adult↗
PubMed1991

Output grating couplers on planar optical waveguides as direct immunosensors.

We demonstrated the feasibility of using integrated optical output grating couplers in direct immunosensing. We monitored as functions of time, first the adsorption of an antigen (Ag) on the waveguide's surface, and subsequently, the binding of the corresponding antibody (Ab), i.e. the formation of the immuno-complex Ag-Ab. The Ag was human immunoglobulin G (h-IgG), and the Ab was rabbit anti-h-IgG. We also studied the adsorption of avidin. The refractive indices nF', thicknesses dF', and surface coverages gamma of the adsorbed adlayers and of the immuno-complex Ag-Ab, respectively, were determined.

Adsorption↗
PubMed1991

[Programmed autologous transfusion in coronary surgery: experience with 106 patients].

Patients undergoing elective coronary bypass surgery can benefit from Preoperative Autologous Blood Donation (PAB), despite some opinions to the contrary, as a complement of intra-operative blood salvage techniques. We report herein 106 patients eligible for coronary bypass surgery included in our PAB program. We observed a very good tolerance owing to strict exclusion criteria, a close monitoring of vital signs, and as far as we are concerned, to the infusion of a macromolecular solution (Plasmion) in a 1:1 ratio, to maintain intra-vascular volume. We chose a volume replacement because the physiological adaptation to hypovolemia is altered by the beta-blocking and/or vasodilating agents which cannot be discontinued in patients with coronary heart disease. The changes in the hematological parameters are not different from those observed in other patients eligible for PAB. The postoperative hemoglobin level is satisfactory and compatible with a normal myocardial function inasmuch as the cardiopathy has been corrected. The efficiency of PAB is good since overall, 74% of the patients did not require homologous blood, this proportion rises to 84% for patients donating 3 or more units. Preoperative Autologous Blood Donation for patients with coronary heart disease implies a perfect coordination between the Blood Bank physicians and their colleagues from the Cardiology Department. Aside from its well known advantages, PAB allows a stimulation of erythropoiesis, a progressive normovolemic hemodilution perhaps beneficial to patients with coronary heart disease, and finally, a better psychological preparation to surgery.

Blood Transfusion, Autologous↗
PubMed1991

[Significance of a specific LH profile after follicle stimulation for producing a pregnancy with IVF/ET].

We report on a retrospective study of LH-profiles after follicular augmentation for in vitro fertilization in order to be able to predict more precisely the chance of success. In 30 out of 34 patients we were able to retrospectively characterize the patients as potentially pregnant or not pregnant. In a prospective application of this statistical method, it should be possible to decide on the basic of specific LH-profiles whether to continue with follicular aspiration or to cancel the cycle in order to increase the pregnancy rate.

Chorionic Gonadotropin↗
PubMed1990

[Echocardiography in emergency medicine: tool or toy?].

In cardiovascular emergency medicine echocardiography allows in many patients a quick and gentle bedside examination. In particular in patients with acute arterial hypotension, suspected or known acute coronary heart disease and its complications and in patients with acute heart failure due to valvular heart disease a valuable narrowing down of the differential diagnosis can be achieved by the use of echocardiography. However, the use of echocardiography in acutely ill patients demands highly skilled investigators to avoid potentially dangerous errors. The echocardiographic examination in intensive or emergency care patients represents an invaluable diagnostic tool today and becomes a toy only in inexperienced hands.

Cardiovascular Diseases↗
PubMed1990

[Hemiparesis and torsade de pointes under low-dose sotalol therapy].

An 81-year-old woman with recurrent epileptic attacks, hemiparesis and rapidly changing consciousness is described in whom the most probable reason for the clinical picture was polymorphous ventricular tachycardia (torsade de pointes). Sotalol (Sotalex), which the patient received for two weeks at a dose of 80 mg twice daily because of asymptomatic ectopic ventricular beats, was identified as the causative agent. Torsade de pointes disappeared after a single intravenous injection of 2 g magnesium sulfate. The patient left the hospital a few days later completely recovered from all neurological deficits.

Aged↗