Involvement of endogenous tumor necrosis factor alpha and transforming growth factor beta during induction of collagen type II arthritis in mice

Both tumor necrosis factor alpha (TNF-alpha) and transforming growth factor beta (TGF-beta) are found in synovial fluid from arthritic joints of humans and of rodents with experimental arthritis. The role of endogenously produced TGF-beta and TNF in the pathogenesis of collagen type II-induced arthritis (CIA) in DBA/1 mice was examined by determining the effect of neutralizing monoclonal antibodies to these factors on the course of the disease. Endogenously produced as well as systemically administered TGF-beta 1 and TNF-alpha had opposite effects, since TGF-beta 1 and anti-TNF protected against CIA, whereas anti-TGF-beta and TNF-alpha increased CIA incidence and/or severity. Intraperitoneally injected TGF-beta 1 at a dose of 2 micrograms per day for 14 days significantly ameliorated arthritis, even when started at the time of arthritis development, although it did not reverse established disease. The resistance to CIA induction caused by a prior intravenous injection of collagen type II was not significantly influenced by the simultaneous injection of TGF-beta 1, TNF-alpha, or interleukin 1 alpha. It is concluded that the endogenous production of TNF and TGF-beta is important in determining the course of CIA.

Testicular feminization: the androgen insensitivity syndrome

Testicular feminization (TF) is a syndrome due to androgen insensitivity. It occurs in a complete (CTF) and an incomplete (ITF) form. We have treated 21 patients with TF over the last 24 years. Eight patients presented because of ambiguous genitalia, seven presented as "females" with inguinal hernia and testes were found at surgery, five were diagnosed by karyotyping performed for a family history of TF, and one presented with an incarcerated hernia and primary amenorrhea. Two patients had prior surgery for inguinal hernia but the diagnosis was not recognized. All patients had a 46,XY karyotype. Patients with CTF were phenotypically female while those with ITF had a variable appearance of the external genitalia depending on the degree of androgen insensitivity. Seventeen patients underwent gonadectomy and one patient planned for delayed gonadectomy was lost to follow-up. Seventeen patients had been raised as females since birth. One patient with ambiguous genitalia, who was initially raised as a male, was reassigned female gender at 1 year of age when the diagnosis of ITF was made. Three patients were raised as males even after the diagnosis of ITF was made. Patients raised as males underwent multiple genital reconstructive procedures with poor results. In view of the poor anatomic and functional results of genital reconstructive surgery and the consequent psychological problems, patients with TF should be raised as female. Careful evaluation of infants with ambiguous genitalia and documentation of absent fallopian tubes in "females" presenting with inguinal hernia will lead to early diagnosis of TF, correct sex assignment, and early gonadectomy.

Identifying drug exposed infants

Better outcome for pregnancy and infant is achieved by identification, intervention and medically appropriate follow up of drug affected pregnancies. Health care professionals should familiarize themselves with the special needs of this special population.

Gastroschisis and intestinal atresia

Controversy exists over the best method of treating gastroschisis with concomitant intestinal atresia because the mortality in such patients is still high. We present our experience of 74 neonates with gastroschisis seen over a 17-year period. Four patients (5.5%) had intestinal atresia; 1 had only one small bowel atresia, 2 had double areas of atresia (one in the mid small bowel and the other in the proximal colon), and the remaining 1 had multiple areas of atresia. Atresia with gastroschisis conventionally has been treated by either primary anastmosis or by exteriorization. Three of the patients were treated by replacing the atretic bowel into the abdomen initially and exploring later (1 to 3 weeks) when the bowel appeared much more healthy, making the anastomosis easier and more secure. One patient with extreme jejunal dilatation was treated by creation of a Mikulicz fistula. All 4 of the patients survived the newborn period, but one of them died at 1 year of age due to total parenteral nutrition-induced chronic liver failure. Our experience is presented to emphasize this uncommonly used approach to this complex problem because it seems to be associated with a lower morbidity and mortality than other conventional approaches.

Protective effect of transforming growth factor beta 1 on experimental autoimmune diseases in mice

Interleukin 1 (IL-1) and tumor necrosis factor alpha are thought to contribute to the inflammatory response associated with autoimmune diseases. Transforming growth factor beta 1 (TGF-beta 1) counteracts many effects of these cytokines and has various immunosuppressive properties. In the present study, it is shown that microgram amounts of TGF-beta 1, injected daily for 1-2 weeks, protect against collagen-induced arthritis (CIA) and relapsing experimental allergic encephalomyelitis (REAE), the animal models for rheumatoid arthritis and multiple sclerosis, respectively. When administered during induction of the disease, TGF-beta 1 prevents CIA but only delays the onset of REAE by 2-3 days. However, when administered during a remission. TGF-beta 1 prevents the occurrence of relapses in REAE. The results suggest that TGF-beta 1 has powerful anti-inflammatory effects, mimicking in some respects the beneficial effects of immunosuppressive drugs in these experimental models of autoimmune disease, but without discernable adverse effects.

Partial splenic embolization. An effective alternative to splenectomy for hypersplenism

Splenectomy for massive splenomegaly and hypersplenism carries a significant morbidity and mortality. We have used partial splenic embolization (PSE) as an effective alternative to splenectomy. Ten PSE procedures were performed on nine patients without mortality and with minimal morbidity. The age of the patients ranged from 8 months to 32 years (mean 14 years). The causes of splenomegaly and hypersplenism included cystic fibrosis with cirrhosis (2), tyrosinemia and cirrhosis (1); thalassemia (1), hemophilia with Human Immune Deficiency Virus infection (2), chronic hepatitis with portal hypertension (1), malignant histiocytosis (1), and Wiskott-Aldrich Syndrome (1). All procedures were performed under local anesthesia with sedation. A percutaneous femoral artery approach to the splenic artery was used to deliver Ivalon sponge particles (280-800 microns) into the spleen. Splenic infarction was assessed by postembolization angiograms. All of the patients except one demonstrated improvement of hematologic parameters. In one patient, however, cytopenia improved only after a second embolization. In the total series, there was an early mean rise of 8,600/mm3 in the leukocyte count (range 2,900-14,900) and 212,000/mm3 in the platelet count (range 30,000-718,000). Follow-up ranged from 4 months to 7 years. Improvement of the blood picture has been persistent in seven of the eight patients who showed initial improvement. Transient procedural complications included fever (5), pleural effusion (2), pneumonia (1), and splenic abscess (1). One patient had paralytic ileus lasting for 10 days and one patient developed a streptococcal peritonitis 3 weeks after embolization. No patient developed pancreatitis or vascular compromise of other abdominal viscera.(ABSTRACT TRUNCATED AT 250 WORDS)

The transport of vitamin B12 through polarized monolayers of Caco-2 cells

Caco-2 cells grown on 0.45-micron filters, in Millicell chambers, form intact monolayers with many of the properties of polarized intestinal epithelial cells. It is reported here that these cells bind and internalize intrinsic factor-cobalamin complexes and that after 14-28 days in culture this specific binding is exclusively located on the apical membrane. Caco-2 cells also synthesize and secrete a protein with properties similar to transcobalamin II. This protein is secreted from the basolateral side of the cells after 20 days in culture. Specific apical-to-basolateral transcellular transport of [57Co]cobalamin also occurs between 20 and 28 days in culture. Thus, Caco-2 cells provide the first polarized human cell system for studying the transepithelial transport of cobalamin.

The pathogenesis of hypochromic anaemia in Saudi infants

The pathogenesis of hypochromic anaemia was studied in 138 Saudi bedouin infants aged 9 months. Approximately 25 per cent had hypochromic anaemia, but less than 10 per cent had serum ferritin levels indicative of iron deficiency. A few infants had heterozygous beta-thalassaemia, but many infants with hypochromic anaemia had normal haemoglobin A2 levels together with serum ferritin levels above 20 micrograms/l. DNA analysis of cord blood taken from the hospital where the infants were born showed that the frequency of the single alpha-globin gene deletion type (-alpha 3.7) of alpha-thalassaemia is 0.13 in the bedouin population of Western Saudi Arabia. alpha-Thalassaemia probably accounts for much of the anaemia previously thought to be due to iron deficiency in Saudi infants. Studies of iron status and estimation of the frequency of genetic causes of hypochromic anaemia are important when assessing the need for widespread nutritional programmes to prevent iron deficiency and in the interpretation of reference ranges of red cell indices in populations from malarial areas.

Molecular analysis of chromosome 1 abnormalities in neuroblastoma

Tumor cells from 70% of neuroblastoma patients contain a deletion of part of the short arm of chromosome 1, indicating that this chromosomal region includes a gene involved in tumor formation. To more precisely evaluate the boundaries and mechanisms involved in generating these deletions, we have examined four neuroblastoma cell lines using a combination of somatic cell hybridization, isozyme analysis, and nucleic acid hybridization employing both standard and restriction fragment length polymorphic probes. The data suggest that the truncation of chromosome 1 in these neuroblastomas was most likely due to a complex translocation and deletion mechanism rather than a simple unbalanced translocation or terminal or interstitial deletion. This conclusion is supported by the frequent removal of MYCL from the altered chromosome 1 to another chromosome. Furthermore, the data suggest that the frequency of breakpoints previously assigned by karyotypic analysis to bands other than 1p32 in neuroblastomas may be overestimated. Finally, this study identified a breakpoint at 1p32 that was localized between the genes JUN and MYCL for one neuroblastoma thus establishing the order of these genes as centromere, JUN, MYCL, telomere. We conclude that the observed breakpoints within chromosome 1p in human neuroblastoma are not as variable as previously described and suggest the results of this study provide evidence for the involvement of specific DNA sequences within 1p32 in the generation of neuroblastoma.

Influence of purinoceptors' agonists and antagonists on opossum internal anal sphincter

Studies were performed in alpha-chloralose-anesthetized and pancuronium-treated opossums. Resting internal anal sphincter pressures (IASP) were monitored using low-compliant continuously perfused catheters. P1 and P2 purinoceptor agonists, adenosine and ATP, respectively, administered close intra-arterially, caused dose-dependent decreases in the IASP. The inhibitory effect of these agonists on the IASP was tetrodotoxin resistant. Rectal balloon distension (RD) (which mimics the rectoanal inhibitory reflex) caused volume-dependent IAS relaxation. Electrical stimulation of the sacral nerve (SNS) also produced frequency-dependent decreases in IASP. The inhibitory response to adenosine (P1 purinoceptor agonist), ATP (P2 purinoceptor agonist), RD, and SNS on the internal anal sphincter (IAS) was examined before and after 8-phenyltheophylline (P1 purinoceptor antagonist) and alpha,beta-methylene ATP (P2 purinoceptor antagonist that irreversibly binds and desensitizes P2 purinoceptor). P1 and P2 purinoceptor antagonists produced selective antagonism of the inhibitory responses on the IAS of their respective agonists only. Furthermore, high doses of adenosine and ATP produced desensitization and block of their own actions only. The purinoceptors' antagonists, and the desensitization of purinoceptors by high doses of adenosine and ATP, failed to modify the fall in IASP in response to RD or SNS. From these studies we conclude that distinct inhibitory P1 and P2 purinoceptors are present on the IAS smooth muscle. However, these inhibitory purinoceptors may not be responsible for the rectoanal reflex-mediated IAS relaxation.

Determinants of anterior mitral leaflet fluttering in pure aortic regurgitation from pulsed Doppler study of the early diastolic interaction between the regurgitant jet and mitral inflow

Fluttering of the anterior mitral leaflet may be absent in patients with moderate to severe aortic regurgitation (AR), suggesting that the volumetric severity of AR alone does not determine the presence or absence of abnormal diastolic mitral valve motion. Fifteen patients with moderate to severe AR and normal mitral valves, 9 of whom demonstrated anterior mitral leaflet fluttering, were studied to elucidate the determinants of abnormal anterior mitral leaflet motion in these patients. Pulsed Doppler mapping of the flow-velocity disturbance of AR demonstrated its presence in the third of the left ventricular outflow tract adjacent to the anterior mitral leaflet in 8 of 9 patients with anterior mitral leaflet fluttering and none of the 6 patients without anterior mitral leaflet fluttering (p less than 0.02). The impact of this regurgitant jet on early diastolic transmitral inflow was examined with pulsed Doppler in these 2 groups of patients with AR and in age-matched control subjects. Deceleration of early diastolic transmitral filling was slower in patients with AR and anterior mitral leaflet fluttering than in age-matched control subjects (283 +/- 107 vs 457 +/- 176 cm/s2, p less than 0.02), whereas it was not significantly different from controls in AR patients without anterior mitral leaflet fluttering. This resulted in significant prolongation of the duration of early diastolic transmitral filling in patients with AR and anterior mitral leaflet fluttering (297 +/- 93 vs 203 +/- 44 ms for age-matched control subjects, p less than 0.02), which was not observed in patients with AR who did not have anterior mitral leaflet fluttering.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetics and metabolism of the antitumor drug amonafide (NSC-308847) in humans

Pharmacokinetics and urinary excretion of Amonafide (5-amino-2-[2-(dimethylamine)ethyl]-1H-benz[de]isoquinoline-1,3-(2H)- dione) were examined in seven patients who were administered 400 mg/m2 of drug as a 30-min infusion on a daily schedule for 5 consecutive days. Amonafide concentrations in plasma and urine were determined using reversed phase HPLC. Amonafide was eliminated from plasma with a terminal half-life of 3.5 hr. Renal excretion accounted for 23% of the administered dose. Amonafide pharmacokinetic parameters after the initial dose (day 1) were similar to those calculated after the fifth daily dose. Amonafide undergoes a significant amount of metabolism and eight urinary metabolites have been identified using a thermospray liquid chromatography-mass spectrometry (LC/MS) technique. Various N-acetylated species appear to be the major metabolites, although no evidence of N-acetylation was found in urine obtained from two patients. Two of the primary metabolites, the N(N5)-acetyl and N'(N1)-oxide metabolites of Amonafide, were tested in vitro for cytotoxicity against P388 murine leukemia cells. In this test system, the N-acetyl metabolite was observed to be only slightly less cytotoxic than the parent compound. The N'-oxide of Amonafide, however, proved to be inactive. These results are discussed together with the pharmacokinetic and metabolism data of this new investigational antitumor drug.

Influence of sacral nerves on the internal anal sphincter of the opossum

The purpose of the present studies is to 1) compare the effects of stimulation of different sacral nerves (S1-S5) on internal anal sphincter (IAS) pressures and 2) examine the nature of synaptic transmission in the sacral inhibitory pathway to the IAS. Pressures from the IAS of alpha-chloralose-anesthetized opossums were recorded using a low-compliance continuously perfused catheter assembly. Electrical stimulation of the third and fourth sacral nerves (S3 and S4) caused frequency-dependent IAS relaxation, whereas stimulation of other sacral nerves was without significant effect on the IAS. Relaxation of the IAS in response to S4 stimulation was not significantly modified by atropine, pirenzepine dihydrochloride, hexamethonium chloride, or adrenergic antagonists. However, a combination of either atropine and hexamethonium or pirenzepine and hexamethonium caused a significant antagonism of sacral nerve-stimulated relaxation without modifying the inhibitory responses of local transmural nerve stimulation and isoproterenol. From these studies we conclude that 1) in the opossum the sacral nerves primarily exert inhibitory influences on the IAS and 2) the sacral inhibitory pathway involves the release of acetylcholine from preganglionic fibers, which in turn causes the activation of both muscarinic (M1) and nicotinic receptors on postganglionic, noncholinergic, nonadrenergic inhibitory neurons.

Actinomyces in cervical smears of women using intrauterine contraceptive devices

Cervical smears from 1,784 women who attended the family planning clinics of the Institute for Research in Reproduction were examined for the presence of Actinomyces-like organisms. Among 815 intrauterine contraceptive device (IUD) users, the repeat smears from 57 women were positive for Actinomyces-like organisms, giving a prevalence rate of 6.99%. Immunofluorescent staining using specific antisera confirmed the presence of A. israelii in all 57 women. Forty IUD users whose smears were positive for Actinomyces-like organisms underwent bacteriologic culture studies; A. israelii was isolated in 23 of these cases. The clinical findings at the time of smear collection in the 57 IUD users were within normal limits. The initial cervical smears of all IUD users and both the initial and repeat smears of all nonusers were negative for Actinomyces-like organisms. The data indicate that prolonged use (greater than 2 years) of an inert or copper intrauterine device promotes the overgrowth of Actinomyces in the vagina and that this can be detected by routine cervical cytology.

Pheochromocytoma: operative strategy

We studied 28 patients who had undergone 30 operations for pheochromocytoma since 1964. The tumor types included bilateral, extra-adrenal, malignant, recurrent, and multiple endocrine neoplasia, with 20 tumors confined to the adrenal gland. The preoperative studies used to localize the tumor included ultrasonography, intravenous urography, angiography, and computed tomography. Patients underwent exploratory operations via flank, subcostal, bilateral subcostal, midline, or thoracoabdominal approaches. In one case, that of a recurrence after bilateral adrenalectomy, surgical exploration discovered a tumor that had not been localized during the preoperative workup. Two patients underwent splenectomy because of injury incurred during operative exploration. Our experience suggests that preoperative localization is highly reliable, and therefore the benefits of extensive surgical exploration may be outweighed by its risks. We believe that with the exception of tumors that occur in association with childhood or pregnancy, multiple endocrine neoplastic syndromes, or recurrent disease, a direct approach to the tumor, possibly via the flank, is justified. Our results suggest that exploration of the contralateral adrenal or periaortic area is not so important as to be worth jeopardizing the spleen or other organs by a complex or extensive dissection.

Posteromedial dislocation of the elbow: a case report

A case is presented in which closed reduction of a dislocated elbow could not be maintained when the forearm was placed in supination. The medial aspect of the patient's posteromedial dislocation was then recognized as significant. Adapting Rangs principles in pediatric patients, the authors again reduced the dislocation, but placed the forearm in pronation, this time maintaining the reduction.

Closure of post laryngectomy pharyngocutaneous fistula with sternocleidomastoid muscle flap

A pharyngocutaneous fistula is an irritating and intractable complication following laryngectomy. These fistulae not only prolong the hospital stay of the patient but pose a potential danger of saliva eroding the carotid vessels. The sternocleidomastoid muscle has a number of uses in reconstructive surgery of the head and neck region and most small or medium sized defects can be closed by use of this muscle flap. This paper reports the use of this muscle flap for the closure of pharyngocutaneous fistulae in 4 cases. All the patients had large fistulae which had not healed after 8 weeks and had prior irradiation. There was no recurrent fistula in these cases.

Fluorescein appearance time curves. Continuous recordings of iris and anterior chamber dye flow contours

Fluorescein appearance time (FAT) curves were recorded at 5-s intervals from the feline iris and anterior chamber using a modified video-frame store unit. Anterior chamber washout slopes were also recorded following intracameral injection. The iris FAT interval following intravenous injection was maximally 5 s. Passage of the dye bolus then appeared during the next 10 s, followed by a rapid (100-s) rise to maximum levels. In contrast to the iris, anterior chamber FAT curves recorded from the pupillary space showed an approximate two-minute delay after injection (mean = 1.92 +/- 0.360 minutes), followed by a gradual (20-minute) rise to maximum recordable levels. The mean anterior chamber washout rate following intracameral injection of 10(-6) g/mL of dye levels was 2.323% +/- 0.810%/min. There are potential applications of the method and a need for shorter recording intervals.

Pain relief after abdominal surgery--a comparison of i.m. morphine, sublingual buprenorphine and self-administered i.v. pethidine

One hundred and twenty-six patients undergoing upper and lower abdominal surgery were studied after operation to compare the analgesic effects of i.m. morphine, sublingual buprenorphine and self-administered i.v. pethidine by Cardiff Palliator. There were no significant differences between analgesic regimens in respect of subjective linear analogue pain scores or static and dynamic lung volumes assessed at 24 and 48 h after operation and 5 days after operation in patients who underwent upper abdominal surgery. Sublingual buprenorphine produced more nausea and sedation than the other two treatments, but the differences were not clinically important. However, it offered considerable advantages in terms of ease of administration.

A study of hospital based ambulance systems in Wisconsin

This study was undertaken to determine the advantages and disadvantages of a hospital-based emergency medical service system with hospital employees serving as emergency medical technicians. This type of service is operating in thirteen hospitals in Wisconsin. A series of interviews was conducted to obtain pertinent information regarding the hospital, emergency medical vehicles, ambulance attendants, finances, communications and personal reactions to the system. The data indicate that hospital-based services using hospital employees can operate with minimal interference to regular patient care, and with apparent advantages to the emergency patients. In the rural, sparsely populated areas which were studied, response times from the hospital-based systems were comparable to other rural systems, and the financial and administrative aspects of the system were reviewed.

Study of the atherogenic dyslipoproteinemia induced by dietary cholesterol in rhesus monekys (Macaca mulatta)

Hypercholesterolemia was induced in adult male rhesus monkeys with a high-fat diet containing an elevated cholesterol level (0.5%). Plasma lipoproteins were chromatographically separated into four size populations (regions) that were subdivided by density until fractions with single electrophoretic mobilities were obtained. The region III lipoproteins (LDL) contained 80% of plasma cholesterol and were present in the highest concentration of all fractions. Their molecular weight was increased over that of controls so that each particle averaged 1.8 times the number of cholesteryl ester molecules as did control LDL. Region II lipoproteins, a heterogeneous group, were present in next highest concentration. Most were cholesteryl ester-rich, beta-migrating lipoproteins that overlapped the VLDL and LDL density ranges; apoB was the predominant apoprotein. One region II subfraction had pre beta 2 migration and the density range. 1.050 less than d less than 1.10. Another subfraction, cholesteryl ester-rich VLDL including only about 1% of plasma cholesterol, had pre beta 1 migration and apoB and apoC as the predominant apoproteins with no apoprotein E. Region I lipoproteins were larger sized, slow beta-migrating cholesteryl ester-rich VLDL that included 5% of plasma cholesterol. ApoB and apoE were the predominant apoproteins. Region IV lipoproteins (HDL) contained 4% of the plasma cholesterol; their concentration was decreased to about 1/3 of the control level. Atherogenic features of the diet-induced dyslipoproteinemia included the increased plasma concentrations and cholesteryl ester contents of the region I, II, and III lipoproteins in addition to the decreased HDL concentration.

T-wave abnormalities of intermittent left bundle-branch block

Ischemia is traditionally considered a cause of intermittent left bundle-branch block (LBBB), and some patients have right precordial T-wave inversion in the normally conducted beats. Clinical correlates of T-wave abnormalities were examined in 46 consecutive patients with intermittent LBBB. Thirty-three patients (72%) had at least transient right precordial (V-14) T-wave inversion suggesting ischemia in normally conducted beats. Seventeen such patients had no evidence of coronary heart disease, including five with normal arteriograms. During LBBB conduction, T-wave abnormalities (upright T-waves I, aVL, V5-6) were frequent (48%) and more common than among patients with permanent LBBB (p less than 0.005). The T-wave abnormalities during LBBB conduction occurred in the absence of coronary heart disease in nine patients, including two with normal arteriograms. Thus, right precordial T-wave inversion may result from recent LBBB itself, associated with T-wave abnormalities during the LBBB, in the absence of coronary artery disease.

Separation and characterization of plasma lipoproteins of rhesus monkeys (Macaca mulatta)

A group of 14 adult male rhesus monkeys was maintained on a low cholesterol-high fat diet. Periodically, animals were fasted and blood samples were taken for characterization of the plasma lipoproteins. Complete separation of individual plasma lipoprotein classes was not achieved by traditional sequential ultracentrifugation techniques. Rather, initial separation of lipoprotein classes according to size was effected and density centrifugation was used subsequently for further separation. At least six lipoprotein fractions were identified, each of which was unique as defined by the properties of size, density (d), and electrophoretic mobility. These lipoprotein fractions were characterized by determination of chemical compositions and apoprotein patterns. The lipoproteins present in highest concentration in these monkeys were designated as region IV lipoproteins. This fraction had alpha-migration on agarose electrophoresis, 1.063 < d < 1.225, and the size, composition, and apoprotein pattern characteristic of HDL. No fewer than three fractions were identified with densities that overlapped the 1.019 < d < 1.063 range. Of these, the fraction designated as region III lipoproteins was present in highest concentration, had beta-migration by agarose electrophoresis, a predominant B apoprotein, and a chemical composition and size characteristic of LDL. Two larger subfractions, identified as region II lipoproteins, were separated from each other at a density of 1.050 g/ml. Agarose electrophoresis showed that the fraction with d < 1.050 had a migration intermediate between beta and pre-beta. The chemical composition and apoprotein pattern were consistent with the possibility that these lipoproteins were remnants of VLDL catabolism. The fraction with d > 1.050, had pre-beta mobility and a size and composition similar to the Lp(a) lipoprotein in plasma of human beings. At least two VLDL subfractions, identified as region I and IIa lipoproteins, were found although both were present in very low concentrations. Region I lipoproteins were larger and contained relatively more cholesteryl ester and more of the apoproteins that migrated with the mobility of apo-B and arg-rich apoprotein in SDS-polyacrylamide gel electrophoresis. Some of the region I lipoproteins were beta-migrating by agarose electrophoresis. These results suggested the possibility that a beta-migrating VLDL was present in these normal animals.

Nitroglycerin and ventricular performance. Differential effect in the presence of reversible and irreversible asynergy

The effect of nitroglycerin administration on left venticular performance relative to its ability to improve contraction of asynergic zones was examined in 66 patients with coronary artery disease, divided into those whose asynergic zones responded following nitroglycerin administration and those in whom no response was observed. In the responsive group with asynergy of more than one segment, the ejection fraction improved (P less than 0.001), while in the unresponsive group, it decreased (P less than 0.05). Similarly, in patients with one-segment asynergy, the responsive group exhibited a significant increase in ejection fraction P less than 0.001), while the unresponsive group showed no change. The stroke volume index remained unchanged in the responsive group with asynergy of more than one segment, while it decreased significantly (P less than 0.05) in the unresponsive patients. Left ventricular pressures and volumes changed to a similar degree after nitroglycerin administration in all of the patients, regardless of the responsiveness of asynergic zones. It is concluded that nitroglycerin administration results in a differential effect on total left ventricular performance depending on the responsiveness of asynergic zones.

Intervention ventriculography. Comparative value of nitroglycerin, post-extrasystolic potentiation and nitroglycerin plus post-extrasystolic potentiation

The comparative value of nitroglycerin (TNG), post-extrasystolic potentiation (PESP) and their combination (TNG + PESP) to unmask asynergic residual contraction was examined, each patient serving as his own control. Twelve of 13 hypokinetic zones improved both with TNG and PESP. One remained unchanged with either. Of 15 akinetic zones, four improved with both TNG and PESP, while ten remained unchanged. One akinetic zone, although improved with TNG, remained unchanged with PESP. Four dyskinetic zones did not change with either. Six asynergic zones responding to TNG alone demonstrated further augmentation with TNG + PESP. However, none of 13 TNG unresponsive zones improved with TNG + PESP. Thus, TNG, PESP, and TNG + PESP are each equally capable of unmasking asynergic residual contractile ability.