Separation of multisized drug suspensions into narrow distributions by centrifugal elutriation

A centrifugal elutriator rotor was used to separate suspensions of micronized hydrocortisone acetate and prednisolone acetate. Up to five distinct particle fractions could beisolated from a single parent suspension, and reasonable reproducibility was exhibited between various elutriator runs. Arithmetic means and associated standard deivations, based on volume, were calculated for each isolated fraction. These data demonstrate the narrowness and uniqueness of each fraction. The particle-size data show an apparent log-normal distribution for each isolate. The uniqueness of each fraction also was demonstrated by dissolution experiments where Fraction 1, the smallest fraction of prednisolone acetate, dissolved much more rapidly than Fraction 4, the largest fraction. The substantial difference in dissolution behavior of these two fractions of prednisolone acetate powder was biopharmaceutically significant.

The effect of inorganic phosphate on sodium fluxes in dog red blood cells

The effect of extracellular inorganic phosphate on Na+ movements in dog red blood cells has been studied. As the phosphate concentration is increased from 0 to 30 mM, Na+ efflux increases by 2- to 3-fold and Na+ influx increases approximately 2-fold. This enhancement of Na+ fluxes by phosphate can be prevented by the addition of iodoacetate (1 mM), an inhibitor of glycolysis, or 4-acetamido-4'-iso-thiocyantostilbene-2,2'-disulfonic acid (0.01 mM), which blocks anion transport, to the medium. The increases in Na+ movements are not caused by changes in cell volumes. These results suggest that phosphate must enter the cell to enhance Na+ fluxes and that the mechanism of action may be via a stimulatory effect on glycolysis.

Aortic origin of the right pulmonary artery

A seven-week-old infant with aortic origin of the right pulmonary artery and patent ductus arteriosus is reported. During preoperative studies, a balloon catheter was used to occlude the ductus arteriosus in order to define the status of the pulmonary vascular bed. Corrective operation was performed by anastomosis of the anomalous right pulmonary artery to the main pulmonary trunk and ligation of the ductus arteriosus. Preoperative assessment of the presence of pulmonary vascular obstructive disease is discussed.

Relationship of contact activation cofactor (CAC) procoagulant activity to kininogen

Contact activation cofactor (CAC) facilitates the interaction of factors XI and XII. Patients lacking CAC have a coagulation defect and are deficient in high molecular weight kininogen. The coincidence of these two defects suggests that a single protein may be responsible for both physiologic functions. Immunologic and activity studies have been made on isolated CAC to clarify the relationship between CAC and kininogen. CAC forms a single precipitin line with anti-human kininogen, and antikininogen neutralizes CAC activity. CAC and high molecular weight kininogen show a reaction of identity on immunodiffusion against rabbit anti-CAC. Anti-CAC forms two precipitin lines with normal plasma which can be identified as high and low molecular weight kininogen. Monospecific immunoabsorbed anti-CAC forms a single precipitin line with plasma high molecular weight kininogen and neutralizes CAC activity. Cleavage of kinin fragment from CAC by insoluble trypsin or kalikrein does not proportionally reduce procoagulant activity. CAC neutralized by anti-CAC can release kinins on exposure to trypsin or kallikrein. The results support the conclusions that CAC procoagulant activity is a function of high molecular weight kininogen, that antigenic determinants unique to high molecular weight kininogen are shared by the CAC portion of the molecule, and that the clotting reactions may occur at a site removed from the kinin peptide.

An extensive rotavirus outbreak in aboriginal infants in central Australia

Faecal specimens were obtained from 92 Aboriginal infants admitted to Alice Springs Hospital during an extensive outbreak of gastroenteritis in the surrounding area in July, 1976. Specimens were examined for potentially pathogenic viruses, bacteria and parasites. Rotavirus proved to be by far the most common potential pathogen, being detected in 54% of specimens.

Aqueous humor ascorbate concentration and open-angle glaucoma

The mean value for aqueous concentration in 35 patients with open-angle glaucoma was 22.4 +/- 12.9 mg/100 ml. The mean value for aqueous ascorbate in four patients with uncomplicated senile cataract was 11.55 +/- 3.01 mg/100 ml. The results indicate that the majority of open-angle glaucomatous eyes do not involve a deficiency of ascorbate, and suggest that ascorbate has no therapeutic value in the management of primary open-angle glaucoma. The magnitude of aqueous ascorbate variation among glaucoma eyes is probably related to the factors that influence the patency of trabecular meshwork, not the metabolic activity of the ciliary processes.

Systemic lupus erythematosus. A review of 110 cases with reference to nephritis, the nervous system, infections, aseptic necrosis and prognosis

Observations made on 110 patients with SLE over a four and a half year period have been reviewed. The patients were seen at intervals of two months when, both clinical and serological findings were recorded, according to a set protocol. The results have been presented with particular reference to nephritis, neurological manifestations, infections, aseptic necrosis, mortality and predicted survival. Such studies have led to the identification of various prognosis factors in SLE, and assisted in providing better directed therapy. The results indicate a milder from of SLE in the patients of this series when compared with previously published studies, and is more representative of the wide spectrum of disease severity seen in the general population.

Evaluation of analgesic action and efficacy of antirheumatic drugs. Study of 10 drugs in 684 patients with rheumatoid arthritis

A single-blind non-crossover method for assessing the potential effectiveness of antirheumatic drugs has been described. The method employs entirely subjective indices and incorporates a daily pain chart for measuring the pain response over the duration of the trial. In addition, the mean number of days withdrawn and patients' satisfaction rating are measured. The statistical method can correct for initial imbalances between groups and allows for the valid comparison of drugs from separate trials. Ten antirheumatic medications were evaluated using this technique in 684 patients with rheumatoid arthritis, and the results are in agreement with those of previous studies using standard clinical methods. The new method is simple, rapid in performance, economical in terms of cost and time, and has been shown to be sensitive and reproducible. The results indicate that there are no significant differences in efficacy between the currently available non-steroidal, anti-inflammatory analgesic drugs, in the treatment of rheumatoid arthritis.

Isolation and carbohydrate composition of glycopeptides of human apo low-density lipoprotein from normal and type II hyperlipoproteinemic subjects

Glycopeptides were prepared from the delipidized protein of low-density lipoprotein (LDL, d=1.019-1.063) of three normal and three familial heterozygous type II hyperlipoproteinemic (HLP) subjects. The glycopeptides of all subjects were resolved into three groups by gel filtration on Bio-Gel P6 following papain (EC 3.4.22.2) digestion and initial purification on Bio-Gel P2. In normal individuals the component of largest molecular weight (F-1) contained mannose (Man), N-acetyl glucosamine (GlcNAc) galactose (Gal), and N-acetyl neuraminic acid (NANA) in the respective amounts of 45.9 +/- 6.7, 37.3 +/- 5.9, 28.6 +/- 3.4, and 27.0 +/- 3.9 nmol/mg original apoprotein. The group of smallest molecular weight (F-3) contained essentially only Man (25.8 +/- 1.5 nmol/mg protein) and GlcNac (3.0 +/- 0.4 nmol/mg protein) with traces of Gal and NANA. A group of intermediate molecular weight (F-2) exhibited considerable heterogeneity and contained Man, GlcNAc, Gal, and NANA in the amounts of 45.9 +/- 5.1, 18.3 +/- 1.7, 11.0 %/- 1.7, and 7.7 %/- 1.2 nmol/mg protein. While the major portion of NANA (78%), Gal (71%), and GlcNAc (64%) was present in F-1, approximately 22% of the total Man was in F-3. No major differences were detected in the carbohydrate composition of the three glycopeptide fractions of LDL apoptotein from normal and Type II subjects.

Aqueous ascorbate concentration in hereditary buphthalmic rabbits

Some aqueous humor constituents, including ascorbate, protein, and sodium, potassium, and calcium ions, were analyzed in three groups of adult buphthalmic (bu/bu) rabbits from strain AXBU/J and in control rabbits of the closely related strain AX/J. Aqueous humor ascorbate concentration of the normal strain was 22.5/"2.3mg/100ml. The buphthalmic rabbits that had no meaningful clinical signs of glaucoma at the time of sample collection had lower values (11.7/"1.7mg/100ml). Much lower values were observed in the bu/bu mutant rabbits that showed mild to severe glaucoma: 8.9/"3.8mg/100 ml and 1.9"/0.4mg/100ml, respectively. It was concluded that reduction of aqueous ascorbate is a biochemical change associated with the pathological development of buphthalmia in rabbits of the AXBU/J strain. However, the exact mechanism is still unclear.

Blood volume changes and production and destruction of erythrocytes in newborn dogs

Erythrocyte, plasma, and total blood volumes were measured in dogs from birth to maturity. All of these volumes (per kilogram of body weight) were significantly greater in the dog at birth than at maturity. Erythrocyte volume decreased during neonatal and postnatal periods to less than that during adult period. Erythrocyte production and destruction were measured with a technique combining dilution method of T-1824 for blood volume measurement with uniform tagging of newly formed erythrocytes with 29Fe. Erythrocyte destruction was high during the first 2 weeks after birth.

Episcleritis and scleritis. A study of their clinical manifestations and association with rheumatoid arthritis

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Kinetics of 3-O-methyl glucose transport in red blood cells of newborn pigs

The glucose-permeable fetal red cells in the pig are entirely replaced by glucose-impermeable adult red cells within a month after birth. This study investigates the kinetic parameters of the glucose transport mechanism in newborn pig red cells in comparison with immature adult red cells (reticulocytes) as well as the fully matured adult erythrocytes. Influx and efflux of the nonmetabolizable 3-O-methyl glucose (3-O-M-G) in red cells of newborn pigs saturate at high substrate concentrations and exhibit typical Michaelis-Menten kinetics. Km values for efflux are 15.2 and 18.2 mM for 15 and 22 degrees C, respectively. Q10 computed between 10 and 26 degrees is 5.0. The energy of activation for the transport process is 34,000 cal mol-1. The effectiveness of hexoses in competing with 3-O-M-G in efflux is in the following order: D-glucose greater than D-mannose greater than D-fructose greater than D-galactose. Efflux of 3-O-M-G does not increase with 3-O-M-G or D-ribose in the medium and is reduced by 2,4-dinitroflurobenzene (DNFB), p-chloromercuriphenyl sufonic acid (PCMBS), and phloridzin. The reticulocytes are shown to possess a carrier-mediated transport but with a considerably lower transport rate. As the reticulocytes mature into normal red cells, the carrier transport mechanism is lost.

The carbohydrate composition of human apo low density lipoprotein from normal and type II hyperlipoproteinemic subjects

The carbohydrate composition of the apoprotein from low density lipoprotein (LDL) of normal (average LDL cholesterol, 122 mg/100 ml) and type II hyperlipoproteinemic (average LDL cholesterol, 236 mg/100 ml) males was studied using gas-liquid chromatographic analysis of the methul glycoside derivatives. All samples containing detectable sinking pre-beta-lipoprotein were excluded from the study. The apo LDL from both groups of subjects contained mannose, galactose, N-acetyl-glucosamine and N-acetylneuraminic acid. Glucose and fucose were not found while trace quantities of galactosamine were detected. Although the quantities of galactose and N-acetylglycosamine were the same in the two groups, lower quantities of mannose (p less than or equal to 0.01) and N-acetylneuraminic acid (p less than or equal to 0.05) were found in the type II patients as opposed to normal subjects.

Partial purification and characterization of contact activation cofactor

The contact phase of intrinsic clotting involves Factor XI, Factor XII, Fletcher factor, and a fourth activity that we call contact activation cofactor (CAC). All four of these activities are reduced or absent in Dicalite-adsorbed plasma. A modified activated partial thromboplastin time assay for CAC has been defined by using a substrate of Dicalite-adsorbed plasma combined with partially purified sources of Factors XI and XII, and Fletcher factor. The following properties of CAC in plasma have been determined by using the assay: it is stable up to 60 min at 56 degrees C; gradually loses activity at 80 degrees C; is stable between pH 6 and 9; is precipitated by ammonium sulfate between 40% and 50% saturation; is slightly adsorbed by A1(OH)3; and is eluted from DEAE-cellulose after the major protein peaks. A purification procedure has been devised that separates CAC from other known clotting factors. Isolated CAC was less stable than CAC in plasma, but in the presence of dilute human serum albumin it retained full activity for 80 min at 56 degrees C. On gel filtration CAC had an apparent mol wt of 220,000 daltons. These properties are consistent with those described for Fitzgerald factor, which further supports the conclusion that CAC and Fitzgerald factor represent the same activity. Isolated CAC promoted the generation of activated Factor XI (XIa) in a mixture containing purified Factor XI, Factor XII, and kaolin. The amount of Factor XIa generated was proportional to the amount of added CAC. No time-consuming reaction between Factor XI or Factor XII and CAC could be demonstrated.

[Clinical study on a new acetylsalicylic acid/paracetamol preparation with gastric acid resistant coating (Safapryn), and on two various phenylbutazone dosages in patients with primary chronic polyarthritis as based on a new evaluation method]

The authors describe a simple non-crossover-blind test for the evaluation of subjective indices. A table for recording pains during the 14 days' study is described. The patient's satisfaction with the treatment and the number of days until withdrawal from the trial are recorded. The statistical procedure takes into consideration differences between the treatment groups and makes possible a valuable comparison with drugs tested in other clinical trials. The three dose schedules of antirheumatic treatment were tested on 122 patients and the results compared with those of 342 patients treated with the 6 other antirheumatic drugs (enteric-coated aspirin, paracetamol, indomethacin, flurbiprofen, mefenamic acid, and prednisolone) and those of 41 patients who received placebos. The results show that Safapryn (3,6 g aspirin + 3.0 g paracetamol daily) compared with 3.9 g enteric coated aspirin does not offer any advantage in its analgesic effect, although it gives rise to fewer side effects. Phenylbutazone (3000 mg) was almost as effective as 15 mg prednisolone daily. Between the effects of this dosage of phenylbutazone and other non-steroidal antirheumatic drugs, however, no significant difference could be detected. 50 mg phenylbutazone daily and placebo treatment could not be distinguished. The authors thank the Arthritis and Rheumatism Council for Research in Great Britain for its financial support. One of the authors (PL) was a Merck, Sharp, and Dohme Research Fellow and another one (PMB) received a Robins research scholarship.