HORMONAL MARKERS IN THE STUDY OF PITUITARY ADENOMAS

Twenty pituitary adenomas were studied using light microscopy, immunohistochemistry and electron microscopy. Based on clinical manifestations of hormonal hypersecretion they were divided into two groups, i.e. group-I (12 patients) with no endocrine dysfunction and group-II (8 patients) with endocrine dysfunction. Group-I could be further sub-divided into two groups based on IHC : group LA in which no hormone could be localised in the tissue (null cell adenomas) and group IB where hormones could be localised in the tissue (1). Tumours in group II, with light microscopy, were acidophil (n=5), basophil (n=1) or mixed (n=2) adenomas. Eight of these 20 cases were plurihormonal. Growth hormone, and prolactin were the commonest combination. This study has helped in the reclassification of the pituitary adenomas according to the hormone they produce.

Clinical studies with the new glycosylated recombinant prourokinase

Recombinant prourokinase (r-ProUK) is a single-chain urokinase-type plasminogen activator that is produced from a mammalian cell line. It is administered as a zymogen and remains inactive until converted to the active two-chain form on the surface of a clot. The clot specificity of this agent, therefore, is conferred by the site of conversion to the active form on the surface of the clot. Two pilot studies were conducted to evaluate the safety and efficacy of r-ProUK in patients with acute myocardial infarction. In the first study, the 90-minute patency rate was 66.7% in 21 patients receiving 60 mg over 60 minutes and 72.2% in 18 patients receiving 60 mg over 90 minutes. In the second study, the 90-minute patency rates were 45.5% in the group primed with recombinant urokinase who were given 60 mg of r-ProUK infused over 60 minutes (11 patients) and 80.8% in the primed group given 60 mg infused over 90 minutes (26 patients). Only 4.6% of patients experienced severe bleeding complications, with no patient developing intracranial hemorrhage. These two studies describe the first application of r-ProUK in patients. Although two doses were selected for evaluation, the small number of patients studied did not permit the selection of one dose as superior to the other. The results, however, did indicate that r-ProUK is a very effective thrombolytic agent in achieving patency of occluded coronary arteries. It is especially effective in maintaining coronary patency, having shown only a 1.4% rate of reocclusion. Serious bleeding complications were few and no intracranial hemorrhages were noted in this group of 131 patients. Additional clinical trials will be needed to compare the efficacy of r-ProUK with that of other available thrombolytic agents.

Comparison of the inverted terminal repetition sequences from five porcine adenovirus serotypes

The nucleotide sequences of the region of inverted terminal repetition from representative strains of all five porcine adenovirus (PAV) serotypes were determined and analyzed. The first 17 nucleotides of this region were identical in PAV-1 to 3 and PAV-5, and 10 bp of identical sequence was found in all the PAVs. The closest relationships were among PAV-1 to 3, which shared more common sequences than the other serotypes. PAV-4 had the longest inverted terminal repeat reported for any adenovirus. The proximal 54-bp AT-rich region was partially conserved and the distal GC-rich region was less well conserved among all five serotypes.

Effect of cadmium chloride on physiological color changes of the fiddler crab, Uca pugilator

The effects of cadmium exposure on the color change system of the fiddler crab, Uca pugilator, were determined. Crabs were either immersed in 10 ppm cadmium chloride solutions or injected with 8.5 micrograms cadmium/g body weight. The crabs exposed to cadmium, either by injection or immersion, were less able to bring about dispersion of the pigment in their integumentary melanophores than were the unexposed crabs. Cadmium did not affect the melanophores directly. This decreased black pigment dispersion was apparently due to effects of cadmium on the neuroendocrine processes that control the melanophores. The neuroendocrine complex in the eyestalk is the source of a black pigment-dispersing hormone (BPDH). Eyestalks of crabs kept in clean water contained 3.27 times more BPDH than did the eyestalks of the cadmium-exposed crabs. Histological studies revealed that cadmium exposure results in depletion of the neurosecretory material in the eyestalks and brain. It is hypothesized that cadmium inhibits BPDH synthesis in neurosecretory (neuroendocrine) cells, resulting in decreased ability of exposed crabs to disperse their black pigment.

Restriction endonuclease analysis and physical mapping of the genome of porcine adenovirus type 5

The HNF61 and HNF70 isolates of porcine adenovirus type 5 (PAV-5) were cultivated in PK-15 cells, and viral DNA was extracted from the infected cells by a modified Hirt procedure. The DNAs were digested by each of 9 restriction endonucleases, and fragments representing the entire genomes were cloned. Based on the sizes of the restriction enzyme fragments, the genome of each isolate was estimated to be 33.2 kb. Physical maps for the 9 restriction endonucleases were constructed. The physical maps of the two isolates were identical for 5 of the restriction endonucleases, but 4 enzymes revealed differences in restriction sites occurring mainly between map units 78 and 83, which may include the E3 region of the genome. There were no similarities between the physical maps of PAV-5 and those described for the other 4 serotypes of PAV.

Predisposing risk factors and natural history of acute neurologic complications of left-sided cardiac catheterization

The reported incidence of acute neurologic complications of left heart catheterization varies from 0.03% to 0.3%. The predisposing risk factors, clinical features, and natural history have not been well characterized. We retrospectively reviewed all cases of acute neurologic complications developing during or within 36 hours of diagnostic catheterization or angioplasty to determine the incidence, clinical features, and natural history, and (using a case-control methodology) the clinical variables associated with their development. During the 37-month study, 6,465 patients underwent diagnostic left-sided cardiac catheterization and balloon angioplasty or valvuloplasty, and 27 patients developed an acute neurologic complication (0.4%). The most common symptoms were visual disturbances (26%), hemiparesis (26%), and facial droop (26%). Deficits were localizable to the anterior or posterior circulation in 22 patients: posterior in 8 (36%), and anterior in 14 (64%). Long-term follow-up was available in all patients, with 17 of 27 (63%) having complete resolution with no residuum. With use of a case-control methodology and multiple logistic regression analysis, female gender, the presence of left ventricular hypertrophy, depressed ejection fraction, and the presence of > or = 2 coronary arteries with > 50% narrowing were independent predictors of a neurologic event.

Sequence analysis of putative pVIII, E3 and fibre regions of porcine adenovirus type 3

Sequence analysis of a region of the genome of porcine adenovirus type 3 from map unit 79.5 to map unit 92 was performed. Homology studies revealed genes coding for the hexon-associated protein pVIII on the left and for the fibre protein on the right of the sequenced region. By analogy with the genomic organization of other adenoviruses, the 1179 bp sequence between the pVIII and fibre open reading frames, extending from map unit 81.3 to map unit 84.7, was identified as the equivalent of the E3 region of human adenoviruses. The deduced amino acid sequence of one of the three open reading frames of the putative E3 region showed homology with the 13.3K E3 protein of canine adenovirus type 2. The primary structure of the putative fibre protein was similar to that described for human adenovirus types 2 and 5, with a 14 pseudorepeat motif in the shaft region of the fibre. A 742 bp tandem repeat starting in the middle of the fibre gene and extending beyond the termination codon of this gene was observed.

Molecular cloning and physical mapping of porcine adenovirus types 1 and 2

The 25R strain of porcine adenovirus type 1 (PAV-1) and the A47 strain of PAV-2 were propagated in ST cells, and DNA was extracted from the infected cells by a modified Hirt method. The DNA of each virus was digested by each of nine restriction endonucleases, and restriction enzyme fragments representing the entire genome were cloned. The genomic size of each virus was approximately 33 kb. Physical maps for the nine restriction endonucleases were constructed from the results of double digestion and Southern blot hybridization experiments, and oriented with respect to the PAV-3 genome. PAV-1 and PAV-2 were found to be related genetically to PAV-3, and there was a closer relationship between PAV-1 and PAV-3 than between PAV-1 and PAV-2 or between PAV-2 and PAV-3.

Evidence for a ppGpp-binding site on Escherichia coli RNA polymerase: proximity relationship with the rifampicin-binding domain

On amino acid starvation, Escherichia coli cells exhibit an adaptive facility termed the stringent response. This is characterized by the production of high levels of a regulatory nucleotide, ppGpp, and concomitant curtailment in rRNA synthesis. Various studies reported earlier indicated that RNA polymerase is the site of action of ppGpp although a direct demonstration of the interaction of ppGpp with E. coli RNA polymerase is still lacking. Here we report the labelling of ppGpp with a fluorescent probe, 1-aminonapthalene-5-sulphonate (AmNS), at the terminal phosphates. AmNS-ppGpp responded much like a ppGpp molecule in an in vitro total transcription assay at selective promoters. Fluorescence titration of the tryptophan emission of RNA polymerase by AmNS-ppGpp indicated a unique binding site in the absence of template DNA. Competition experiments showed that unlabelled ppGpp binds to the enzyme at the same site. Sigma factor seems to have no effect on this binding. The titration profile is also characterized by a single slope in the Scatchard analysis. The presence of GTP or GDP does not influence the binding of AmNS-ppGpp with RNA polymerase. Forster's distance measurement was carried out which placed AmNS-ppGpp 27 A away from the rifampicin-binding domain of RNA polymerase.

Changes in oxidative metabolism in selected tissues of the crab (Scylla serrata) in response to cadmium toxicity

Changes in oxidative metabolism were studied in hepatopancreas, muscle, and hemolymph of the edible crab Scylla serrata, exposed to a sublethal concentration (2.5 ppm) of cadmium chloride. A significant decrease in glycogen, total carbohydrates, and pyruvate and an increase in lactate levels in hepatopancreas and muscle were observed. Hemolymph sugar levels were increased in experimental crabs. An increase in phosphorylase suggested increased glycogenolysis during cadmium toxicity. The decrease in lactate dehydrogenase activity and the increase in lactate content indicated reduced mobilization of pyruvate into the citric acid cycle. Krebs cycle enzymes such as succinate dehydrogenase and malate dehydrogenase were found to be decreased, suggesting impairment of mitochondrial oxidative metabolism as a consequence of cadmium toxicity. Glucose-6-phosphate dehydrogenase activity was increased, suggesting enhanced oxidation of glucose by the HMP pathway. Cytochrome-c oxidase and Mg2+ ATPase activity levels decreased, indicating impaired energy synthesis during cadmium stress. Acid and alkaline phosphatase activities increased, suggesting enhanced breakdown of phosphates to release energy in view of impaired ATPase system during cadmium exposure. A significant decrease in protein and free amino acid and an increase in ammonia, urea, and glutamine levels were observed in the tissues during exposure. An increase in protease, alanine aminotransaminase, and aspartate aminotransaminase suggested increased proteolysis and transamination of amino acids. The increase in glutamate dehydrogenase, AMP deaminase, and adenosine deaminase indicated increased ammonia production. The increased arginase and glutamine synthetase suggested the detoxification or mobilization of ammonia toward the production of urea and glutamine. These results suggest that cadmium affects oxidative metabolism and induces hyperammonemia, and crabs switch over their metabolic profiles toward compensatory mechanisms for the survivability in cadmium-polluted habitats.

New recombinant glycosylated prourokinase for treatment of patients with acute myocardial infarction. Prourokinase Study Group

OBJECTIVES

Three dosage regimens of a new recombinant glycosylated prourokinase (A-74187) were evaluated by measuring coronary artery patency at 90 min in patients with acute myocardial infarction.

BACKGROUND

Prourokinase is a thrombolytic drug with unique pharmacologic properties that may be clinically advantageous.

METHODS

Aspirin (325 mg), intravenous heparin and prourokinase (60- or 80-mg monotherapy or 60 mg "primed" with a preceding bolus dose of 250,000 IU of recombinant urokinase) were administered to 128 patients. Coronary angiography was performed at 60 min (wherever possible), 90 min (primary end point) and 24 h to determine arterial patency and reocclusion rates. Plasma was collected serially to measure fibrinogen, plasminogen, thrombin antithrombin III and fibrinopeptide A. Clinical events until hospital discharge were recorded.

RESULTS

The coronary artery patency rate at 90 min was similar for all three regimens, averaging 73% (95% confidence interval [CI] 64% to 80%); Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow rates averaged 52% (95% CI 42% to 61%). Arterial patency at 60 min was 62% (95% CI 50% to 73%), and reocclusion occurred in 1.4% (95% CI 0.1% to 4.1%). Prourokinase demonstrated relative fibrin specificity at all doses studied. Fibrinopeptide A and thrombin antithrombin III levels were elevated at baseline and declined rapidly during the 1st 12 h. There was no difference in the baseline values of these thrombin markers between patients with patent versus closed arteries at 90 min. There was one death; no strokes occurred.

CONCLUSIONS

A-74187 prourokinase is a rapid-acting, effective fibrin-specific thrombolytic agent. Reocclusion was unusual, possibly because of aggressive anticoagulation with intravenous heparin or unique features of the drug. Full definition of the clinical effectiveness of this drug merits examination in future randomized trials evaluating clinical and angiographic effectiveness.

Evidence for a pyrimidine-nucleotide-specific initiation site (the i site) on Escherichia coli RNA polymerase. Proximity relationship with the inhibitor binding domain

Escherichia coli RNA polymerase has two sites, the i and i + 1, for the binding of the first two substrates. The i site is template- and Mg(2+)-independent and purine-nucleotide-specific, whereas the i + 1 site is template- and Mg(2+)-dependent and shows no nucleotide preference. The specificity of the i site for purine nucleotides is well in accord with the fact that most promoters initiate with a purine nucleotide. But there are a few promoters that initiate with a pyrimidine nucleotide. Dinucleotide synthesis at these promoters is completely inhibited by rifampicin. Earlier studies have failed to identify an i site for pyrimidine nucleotides. In this paper, using a fluorescent analog of UTP, namely uridine 5'-[gamma-(5-sulfonic acid)naphthylamidate]-triphosphate, abbreviated as UTP[AmNS], we are able to show its binding to RNA polymerase, with a Kd of 0.8 microM, in the absence of Mg2+ and template. This suggests the presence of an i pyrimidine nucleotide site. The fact that UTP-[AmNS] is capable of initiating RNA synthesis from the i site is further evidenced by the abortive transcription analyses at the lac promoter. Fluorescence titration studies performed in the presence and absence of purine initiator molecules indicate that this site is different from the i purine site. Scatchard analysis of the above data indicates the presence of a single binding site for UTP[AmNS] in the absence of Mg2+. Moreover UTP[AmNS] binds to the core enzyme with a Kd of 3.0 microM implying that, unlike the i purine nucleotide site, the sigma protein confers a tighter binding of UTP-[AmNS] to the low-Kd site. Forster's energy transfer measurements using UTP[AmNS] as the donor and rifampicin as the acceptor have been used for estimation of the distance of the i pyrimidine nucleotide site from the rifampicin site. From these measurements, we infer that there is no direct interference of rifampicin with the first phosphodiester bond between two pyrimidine nucleotides.

Design, synthesis, and study of 9-substituted ellipticine and 2-methylellipticinium analogues as potential CNS-selective antitumor agents

N,N-Dimethylformamide (DMF) dineopentyl acetal-mediated O-alkylations of 9-hydroxyellipticine gave 9-ethoxy-, 9-(1-methylethoxy)-, and 9-(1,1-dimethylethox)ellipticine (3a, 4a, and 5a, respectively). Methylation of the O-alkylellipticines gave the corresponding N-methylpyridinium iodides (3b, 4b, and 5b). The iodides were converted to the acetates (3c, 4c, and 5c) by ion-exchange resin. Attempts to prepare 9-(2,2,2-trifluoroethoxy)ellipticine (6a) using the DMF acetal gave 10-(2,2,2-trifluoroethoxy)-9-hydroxyellipticine (8a). 9-(2,2,2-Trifluoroethoxy)- and 9-phenoxyellipticine (6a and 7a, respectively) were prepared by total synthesis. The ellipticines and N-methylellipticinium derivatives were evaluated for in vitro antitumor activity against a panel of human tumors. 2-Methyl-9-(1,1-dimethylethoxy)ellipticinium acetate (5c) was inactive, but all of the other compounds exhibited significant antitumor activity. The ellipticines showed no significant subpanel specificity; however, the N-methylellipticinium compounds tested did exhibit specificity for the CNS tumor subpanel.

Modulation of protein metabolism in selected tissues of the crab, Oziotelphusa senex senex (Fabricius), under fenvalerate-induced stress

Crabs, Oziotelphusa senex senex, were exposed to sublethal concentration (0.2 ppm) of fenvalerate, and changes in the protein metabolism of hepatopancreas and muscle were investigated. The levels of total and soluble proteins were decreased, whereas the levels of the free amino acids and activity levels of protease, alanine transaminase, aspartate transaminase, and glutamate dehydrogenase were significantly increased in the tissues of crabs exposed to fenvalerate. The changes were more pronounced with an increase in the period of exposure. The possible adaptive significance of these changes during fenvalerate intoxication in the crab is discussed.

Utilisation pattern and managerial issues--a study of emergency medicine department at Nizam's Institute of Medical Sciences, Hyderabad

The emergency medicine department (EMD) is one of the youngest department in the Nizam's Institute of Medical Sciences (NIMS). The study was conducted for a period of six months from it's inception, since November 01st 1992. The physical facilities, staffing, policies and procedures, work load and cost analysis were studied, and conclusions and suggestions were given. Total patients attended at EMD in the six months were 6,884, out of whom 3,484 were admitted into the hospital for further treatment. Cost analysis showed a net gain of Rs. 78.80 per patient.

Synthesis, chemical reactivity, and antitumor evaluation of congeners of carmethizole hydrochloride, an experimental "acylated vinylogous carbinolamine" tumor inhibitor

A series of analogues of 4,5-bis(((N-methylcarbamoyl)oxy)methyl)-1-methyl-2-(methylthio)-im idazole (1, carmethizole) were synthesized. The chemical reactivities of the analogues (as electrophiles) were evaluated and related to the antitumor activity (in vivo and in vitro). Changes in the alkylthio moiety had a significant effect upon the chemical reactivity. Electron-withdrawing groups on the sulfur decreased chemical reactivity and, in parallel, decreased antitumor activity. Carmethizole sulfoxide (11a) was unreactive as an electrophile and exhibited no antitumor activity either in vivo or in vitro; this led to the conclusion that carmethizole sulfoxide was not acting as a "carrier form" of carmethizole. The disulfides 17 and 18 were unreactive as electrophiles but did exhibit antitumor activity. The activity of 17 and 18 was attributed to the thiol 10 that would be generated upon cleavage of the disulfide bond.

Preoperative pulmonary hemodynamics and early mortality after orthotopic cardiac transplantation: the Pittsburgh experience

The influence of preoperative transpulmonary pressure gradient (TPG) and pulmonary vascular resistance (PVR) on early post-transplant mortality was evaluated in 425 orthotopic transplant recipients. The overall 30-day post-transplant mortality rate was 12.5%; the majority of the deaths (52.8%) were due to primary allograft failure. The 0- to 2-day mortality rate was threefold higher in patients with severe preoperative pulmonary hypertension (TPG > or = 15 mm Hg or PVR > or = 5 Wood units), whereas the 3- to 7-day and 8- to 30-day mortality rates were similar. Early post-transplant mortality (0 to 2 days and 8 to 30 days) was also significantly higher (15.9% vs 3.9% and 9.9% vs 2.8%, respectively; p < 0.05) in women compared with men. Women with severe preoperative pulmonary hypertension had higher (p < 0.05) 0- to 2-day post-transplant mortality than comparable men. According to univariate analysis, recipients with preoperative TPG > or = 15 mm Hg had a significantly higher 30-day postoperative mortality rate, irrespective of their level of PVR. Furthermore, patients with severe preoperative pulmonary hypertension who underwent transplantation between 1980 and 1987 had a higher 0- to 2-day post-transplant mortality rate compared with patients operated on after that time. Multiple logistic regression analysis identified female recipient sex and preoperative TPG but not preoperative PVR, era of transplantation, or recipient age as significant (p < 0.001 and p < 0.01, respectively) independent predictors of early post-transplant mortality.

Ultrasound-assisted cannulation of the internal jugular vein. A prospective comparison to the external landmark-guided technique

BACKGROUND

Central venous access is an essential part of patient management in many clinical settings and is usually achieved with a blinded, external landmark-guided technique. The purpose of this study is to evaluate whether an ultrasound technique can improve on the traditional method.

METHODS AND RESULTS

We prospectively evaluated an ultrasound-guided method in 302 patients undergoing internal jugular venous cannulation and compared the results with 302 patients in whom an external landmark-guided technique was used. Ultrasound was used exclusively in an additional 626 patients. Cannulation of the internal jugular vein was achieved in all patients (100%) using ultrasound and in 266 patients (88.1%) using the landmark-guided technique (p < 0.001). The vein was entered on the first attempt in 78% of patients using ultrasound and in 38% using the landmark technique (p < 0.001). Average access time (skin to vein) was 9.8 seconds (2-68 seconds) by the ultrasound approach and 44.5 seconds (2-1,000 seconds) by the landmark approach (p < 0.001). Using ultrasound, puncture of the carotid artery occurred in 1.7% of patients, brachial plexus irritation in 0.4%, and hematoma in 0.2%. In the external landmark group, puncture of the carotid artery occurred in 8.3% of patients (p < 0.001), brachial plexus irritation in 1.7% (p < 0.001), and hematoma in 3.3% (p < 0.001).

CONCLUSIONS

Ultrasound-guided cannulation of the internal jugular vein significantly improves success rate, decreases access time, and reduces complication rate. These results suggest that this technique may be preferred in complicated cases or when access problems are anticipated.

Restriction endonuclease analysis and molecular cloning of porcine adenovirus type 3

The 6618 strain of porcine adenovirus type 3 was cultivated in swine testis cells, and viral DNA was extracted from the infected cells by a modified Hirt procedure. The DNA was digested by each of 13 restriction endonucleases, and the number of cleavage sites which were identified varied from 1 to 17. The size of the porcine adenovirus type 3 genome, estimated from the sizes of the restriction enzyme fragments, was approximately 35 kb. Fragments representing the entire genome were cloned. Physical maps were constructed based on the results of restriction endonuclease analyses and hybridization and oriented with respect to the genome of bovine adenovirus type 3.

Randomized trial of thrombolysis versus heparin in unstable angina

BACKGROUND

The clinical usefulness of intravenous thrombolytic therapy in unstable angina is currently unknown, despite the pathogenetic similarity of this entity to acute myocardial infarction, for which thrombolysis has enjoyed great success. To compare the clinical benefit of intravenous urokinase with that of conventional antithrombotic therapy in preventing the progression of unstable angina to new myocardial infarction, intractable angina, or death within the first 96 hours after hospitalization, 149 patients with unstable angina were randomized to one of two intravenous thrombolytic strategies.

METHODS AND RESULTS

Forty-nine patients received 3 million units urokinase i.v. over 90 minutes plus intravenous heparin (group A); 47 patients received unblinded 3 million units urokinase i.v. plus 325 mg aspirin p.o. daily (group B); and 53 patients received placebo thrombolytic infusion plus full-dose heparin (group C). The primary end point of this trial was 96-hour clinical status. There were no significant differences in the baseline characteristics (age, sex, previous myocardial infarction, hypertension prevalence, diabetes, tobacco use, or previous revascularization) among the three groups. Despite an excess of minor untoward reactions for the urokinase groups (chills, 26.5% and 23.4% for groups A and B versus 0% for group C; p < 0.01), there was no significant difference with respect to major bleeds (two, none, and two for groups A, B, and C, respectively; p = NS). At 96 hours after presentation, no significant difference emerged in the incidence of new cardiac events: new myocardial infarctions developed in 10.2% of group A, 6.4% of group B, and 3.8% of group C (p = NS); intractable angina occurred in 6.1% of group A, 10.6% of group B, and 9.4% of group C (p = NS). There were no deaths. All three groups encountered a similar incidence of overall cardiac events: 16.3%, 17.0%, and 13.2% for groups A, B, and C, respectively (p = NS). Although trial enrollment was to extend to 600 patients, interim analysis led to early cessation of enrollment due to a negative trend in respect to outcome after thrombolysis.

CONCLUSIONS

High-dose intravenous urokinase followed by either heparin or aspirin can be safely administered to a broad, unselected group of patients with unstable angina. However, this study suggests that no clinical advantage is conferred by urokinase, with either adjunctive antithrombotic therapy over standard heparin therapy alone, when given relatively late (mean, 8.7 hours) after admission for unstable angina. A possible detrimental effect cannot be excluded.