Toothbrushing and transient bacteremia in patients undergoing orthodontic treatment

A study was made to determine the extent of bacteremia experienced by patients undergoing orthodontic treatment with fixed appliances during periods of routine oral hygiene--namely, brushing the teeth. Sixteen orthodontic patients made up the population--11 who practiced good oral hygiene and five who demonstrated poor oral hygiene. Blood was drawn aseptically from the median cubital vein of the subjects before and 15 minutes after brushing the teeth. An aliquot of each blood specimen was added to separate blood culture bottles and incubated at 37 degrees C for a period of up to 5 days. Blood was also used to determine the immune status of the subjects. Anaerobic bacteria were recovered from the blood of nine of the 16 patients studied; aerobic bacteria were not recovered. A negative blood culture before brushing and positive blood culture after brushing were expected but did not occur. Some subjects showed bacteremia before brushing and a negative blood culture after brushing. Others showed bacteremia before and after brushing. The unexpected results could be attributed to the patients eating and/or brushing before starting the test. The study showed the capacity of specific anaerobic bacteria to remain in the bloodstream for a 15-minute period. It also demonstrated a presence of bacteria in the bloodstream before the test began.

A rapid, simple synthesis and purification of abscisic Acid glucose ester

A simple and rapid technique was developed to synthesize abscisic acid glucose ester. The free acid of abscisic acid (ABA) was combined with CsHCO(3) to form the Cs salt of ABA. The Cs salt of ABA was then combined with acetobromo-alpha-d-glucose tetraacetate, and the tetraacetate derivative of abscisic acid glucose ester was formed. Acetate groups were selectively removed from the glucose moiety with a crude enzyme preparation derived from Helianthus annuus seeds. Abscisic acid glucose ester was purified via silica gel column chromatography and identified by micro NMR.

Synthetic inhibitors of carboxypeptidase N

Further to explore the functions of carboxypeptidase N (CPN) in vivo, we undertook two studies to find CPN inhibitors of high potency and relatively long duration of action. In each study we examined for inhibition of hydrolysis of [3H]benzoyl-Ala-Arg using pure bovine serum CPN or human serum. In the first such study we synthesized a series of acyl amino acids and acyl di - and tripeptides containing arginine, lysine or both. All proved to be weak inhibitors (Ki = 10(-3) to 10(-4) M). N alpha-carbamoyl-Arg was the strongest: Ki = 3.5 X 10(-5) M. In the second study we prepared S-acyl (thio ester) derivatives of the highly potent CPN inhibitor 2-mercaptomethyl-3-guanidinoethylthiopropionic acid (2-MGP), as certain S-acyl groups markedly increase the duration of captopril, another mercapto-containing compound. Acetyl-, Boc-phenylalanyl-, phenylalanyl-, benzoyl-alanyl-, alanyl-, and Boc-alanyl-2-MGP retained the high potency of 2-MGP in vitro. Although Ala-2-MGP exerted maximum effects in vivo, like those of 2-MGP, the duration of action of Ala-2-MGP was slightly shorter than that of 2-MGP. These results indicate that the mercapto group of 2-MGP can be taken up in some forms of thioester linkage and still remain virtually the full potency of 2-MGP itself. Thus, it appears that a free mercapto function is not essential for the action of 2-MGP.

Assessment of methods for cytomegalovirus antibody testing of blood donations

As part of a programme to establish a panel of individuals with high titres of anticytomegalovirus (CMV) IgG for the production of CMV Ig, the CMV serostatus of 139 normal blood donors was determined by indirect haemagglutination assay, enzyme immunoassay, and complement fixation. The indirect haemagglutination assay was the most accurate and convenient method for the detection of CMV antibody negative donations. Plasma for production of hyperimmune CMV IgG could best be selected by an IgG-specific enzyme immunoassay procedure.

A third example of haemolytic auto-anti-Vel

A non-transfused, 43 year old Caucasian female presented with acute haemolytic anaemia and splenomegaly. Sections of bone marrow showed erythroid hyperplasia. The patient's red blood cells gave a negative reaction with polyspecific antiglobulin serum, but a positive reaction with specific anti-IgM. A heat eluate prepared from her red cells showed anti-Vel specificity. Her serum agglutinated only Vel-positive cells including her own. All papain pre-treated red cells including her own and Vel-negative cells were completely haemolysed at 37 degrees C. The percentage of haemolysis of Vel-positive cells was greater than that of Vel-negative cells.

Fine structure of the glomerular basement membrane and immunolocalization of five basement membrane components to the lamina densa (basal lamina) and its extensions in both glomeruli and tubules of the rat kidney

Electron microscopic immunostaining was used to examine the localization of type IV collagen, laminin, entactin , heparan sulfate proteoglycan, and fibronectin within the basement membranes of the rat kidney. In preliminary experiments, various methods of processing formaldehyde-fixed kidney were compared using antilaminin antiserum and the indirect immunoperoxidase method. Little or no laminin immunostaining of the glomerular basement membrane was present in sections unless they had been frozen-thawed; and even in this case, the immunostaining was light in comparison to that of basement membranes in adjacent tubules. However, when frozen-thawed sections were treated with 0.5% sodium borohydride, immunostaining was then as strong in glomerular as in tubular basement membranes. Accordingly, this treatment was applied to frozen-thawed sections before immunostaining for any of the substances under study. Immunostaining of the glomerular basement membrane for each of the five substances was fairly uniform throughout the lamina densa (also called basal lamina), but uneven in the lamina lucida interna and externa (also called lamina rara interna and externa) in which stained bands extended from the lamina densa. Similarly in the basement membranes of tubules, immunostaining for the five substances was localized to the lamina densa and bands extending into the lamina lucida. When the ultrastructure of the glomerular basement membrane was examined, three structures were found: (1) a network of 4-nm-thick "cords," which seems to be the main component; the cords are closely packed in the lamina densa and more loosely arranged in the lamina lucida interna and externa; (2) straight, hollow 7-10-nm-thick structures referred to as " basotubules "; and (3) 3.5-nm elements composed of minute paired rods, referred to as "double pegs." The distribution of the cords, but not that of the other two structures, was related to the immunostaining pattern. It is concluded that (1) to fully reveal the antigenicity of the glomerular basement membrane, frozen-thawed sections must be treated with sodium borohydride prior to immunostaining, possibly because this basement membrane is more compact than the others; and (2) in both glomerular and tubular basement membranes, type IV collagen, laminin, entactin , heparan sulfate proteoglycan and fibronectin are colocalized in the lamina densa and its extensions to the laminae lucidae . Since the distribution of the cords corresponds to that of immunostaining, it is likely that the five substances are present within the cords.

The upper and lower bounds of rate constants for general mammillary compartment systems

The upper and lower bounds of rate constants for general mammillary three and four compartment systems have been derived. It is further proposed that the midpoints of the bounds can be used as initial estimates for parameter estimation. Numerical examples are given demonstrating the closeness of the calculated midpoints to the "known" rate constants of both the three and four compartment systems.

Detection of anti-varicella-zoster virus antibodies in blood donors by automated passive haemagglutination

1,219 normal blood donors were screened for anti-varicella-zoster virus antibodies by automated passive haemagglutination (APH) on a Technicon 15-channel AutoAnalyzer. 98 samples (8%) were positive by APH and 92% of these were shown to have antibody titres greater than or equal to 1/16 by indirect immunofluorescence assay (IFA). Parallel testing on an additional 265 donors revealed that 11 (4%) individuals had IFA titres greater than 1/16 and 6 of these 11 donors were identified by APH. Thus, APH is an effective means of rapidly detecting units of plasma acceptable for production of varicella-zoster immunoglobulin.

Biliary lipid synthesis and secretion in gallstone patients before and during treatment with chenodeoxycholic acid

The interrelationships between biliary lipid secretion and the hepatic activities of the rate-limiting enzymes for bile acid and cholesterol synthesis have not been investigated in patients with gallstones before and during desaturation therapy. Liver biopsies for enzyme assays and biliary lipid secretion measurements were performed in 12 patients with gallstones before chenodeoxycholic acid therapy and in nine of these patients at 9 months of therapy. Six nongallstone control patients underwent only the lipid secretion measurements. In the patients with gallstones before treatment, all of whom had saturated bile, increased cholesterol secretion correlated directly with increased HMGCoAR activity, whereas bile acid and phospholipid secretion rates were significantly lower than in controls. During desaturation in response to chenodeoxycholic acid, biliary cholesterol and phospholipid secretion rates decreased significantly, and bile acid secretion was unchanged. Concomitantly, both HMGCoAR and cholesterol 7alpha-hydroxylase activities decreased significantly, but the correlation between HMGCoAR and cholesterol secretion was lost. Furthermore, no correlation was found between cholesterol 7alpha-hydroxylase activity and bile acid secretion during therapy. Enzyme assays were performed on single liver samples obtained at the same time of day but 48 hr before the lipid secretion measurements. That correlations between data obtained under these conditions are valid remains to be proved. In conclusion, the mechanism of biliary cholesterol saturation in patients with gallstones probably is related primarily to increased hepatic cholesterol synthesis, whereas desaturation during chenodeoxycholic acid therapy involves altered relationships among hepatic enzyme activities and biliary lipid secretions.

Phenobarbital specific antibody production: preparation of 5-phenyl-5-(4-aminobutyl) barbituric acid-bovine serum albumin conjugate

The aminobutyl derivative of phenobarbital, 5-phenyl-5-(4-aminobutyl)barbituric acid hydrochloride, was synthesized through two synthetic pathways for the preparation of immunogen in production of phenobarbital specific antibody. The produced antiserum had high titer, specificity, affinity and sensitivity (0.5ng/ml), when examined by radioimmunoassay.

The effect of dihydroxy bile acids on intestinal secretion, cyclic nucleotides, and Na+-K+-ATPase

The effects of dihydroxy bile acids on intestinal cyclic nucleotides, Na+-K+-ATPase, and net secretion, and of propranolol pretreatment on these actions were determined. Ileal and colonic loops were constructed in each of 12 rabbits, six of which were treated with propranolol preoperatively. In random order, normal saline, 6mM deoxycholic, chenodeoxycholic, or ursodeoxycholic acids were injected into the intestinal loops. Five hours after, net luminal secretion and mucosal adenylate cyclase, phosphodiesterase, cGMP, and Na+-K+-ATPase were determined. Deoxycholic and chenodeoxycholic acids each increased adenylate cyclase activity (< 0.01) and net secretion (p < 0.01), and decreased cGMP (p < 0.05). Ursodeoxycholic acid did not alter adenylate cyclase activity or secretion but increased cGMP (p < 0.05). Phosphodiesterase and Na+-K+-ATPase were unchanged. Propranolol reversed all of the bile acid effects. In conclusion, chenodeoxycholic and deoxycholic acid induce net intestinal secretion, probably via cAMP. Ursodeoxycholic acid does not affect cAMP but increases cGMP and does not promote net secretion.

Angiotensin-converting enzyme: I. New strategies for assay

The disposition of converting enzyme (kininase II) on the luminal surface of pulmonary endothelial cells is well established. Further, it is known that there is a net conversion of angiotensin I into angiotensin II as blood passes through the lungs. However, little is known about modulations of converting enzyme activity that may arise through, e.g., changes in the quality of inhalants, blood flow, or blood oxygenation. There are few data on the effects of lung disease. A major barrier to studies to examine for pathophysiologic modulations of converting enzyme is that of assay. The enzyme can be measured in terms of the rate of formation of angiotensin II from a known quantity of angiotensin I. However, both peptides are biologically active, and lungs contain other enzymes capable of degrading them. We have developed a series of radiolabeled, acylated tripeptides to improve our ability to examine for changes in the net converting enzyme of intact lungs. The enzyme, a dipeptidyl carboxypeptidase, is capable of removing C-terminal dipeptides from a variety of oligopeptides. We have prepared benzoyl-Gly-Gly-Gly (I), benzoyl-Pro-Phe-Arg (II), benzoyl-Gly-His-Leu (III), benzoyl-Phe-Ala-Pro (IV), and benzoyl-Phe-His-Leu (V), each containing a (3)H-atom in the para position of the benzoyl moiety. Substrates I and III have been used previously in photometric assays of low sensitivity. II is the acylated C-terminal tripeptide of bradykinin, IV is an acylated tripeptide analog of BPP(5a) (<Glu-Lys-Trp-Ala-Pro) and V is the acylated C-terminal tripeptide of angiotensin I. These substrates can be used in vitro or in vivo to measure converting enzyme. The (3)H-labeled product is separable by partitioning between an organic solvent and acidified aqueous solution. The product is quantified by scintillation counting of the organic phase. The choice of substrate depends on the goals of the experiment: substrate I or III when wide variations in substrate concentrations are needed but high sensitivity is not; substrate IV when high sensitivity is needed.

Capillaries of the adrenal cortex possess aminopeptidase A and angiotensin-converting-enzyme activities

The enzymes required to convert the prohormone angiotensin I into angiotensins II and III, secretagogues of aldosterone, are enriched in association with capillary endothelium isolated from rat adrenal cortex. Thus the secretion of aldosterone may be controlled, in part, by processing of peptides occurring within the adrenal gland itself.

Fate of bradykinin-potentiating peptide 9a after intravenous injection

The fat of less than Glu1-3H-labelled bradykinin-potentiating peptide 9a [BPP9a; less than Glu-Trp-Pro-Arg-Pro-Gln-Ile-Pro-Pro, an inhibitor of angiotensin-converting enzyme (peptidyl dipeptidase)] was studied in the rabbit. After intravenous injection, BPP9a was rapidly removed from blood and much of the associated radioactivity was excreted in urine. Approx. 8% of the radioactivity in urine collected 2h after drug administration occurred in the form of BPP9a itself, the remainder occurring in three lower homologues: less than Glu-Trp (60%), less Glu-Trp-Pro-Arg-Pro-Gln (20%) and less than Glu-Trp-Pro-Arg-Pro-Gln-Ile (12%). Hydrolysis was not accounted for by enzymes in blood or urine. Apparently hydrolysis occurred within the kidney, as less than Gl-Trp was obtained in 60% yield in urine of isolated rat kidney perfused with [less than Glu1-3H]BPP9a.

Cholesterol gallstone formation and prevention by chenodeoxycholic and ursodeoxycholic acids. A new hamster model

Prior animal models of cholesterol gallstone formation have been criticized for their dissimilarity to the conditions of humans with gallstones. We present a new hamster model of cholesterol cholelithiasis that more closely approximates the human situation. Sixty female Golden Syrian hamsters (average weight 83.2 +/- 3.4 g) were allocated to six groups of 10 animals each. Groups were fed standard diet (containing 0.8 gm cholesterol/g of food) or increased cholesterol diet (containing 2.4 mg cholesterol/g of food), with or without ethinyl estradiol, 15 micrograms/kg/d. Two groups receiving both increased cholesterol and ethinyl estradiol also received either chenodeoxycholic acid or ursodeoxycholic acid, 20 mg/kg/d. The animsl were sacrificed at 12 wk. Cholesterol gallstones (78.3 +/- 5.0% cholesterol by weight) formed in 30% of the animals fed ethinyl estradiol, 50% of those fed increased cholesterol, and 90% of those fed the combination of both. Bile was saturated in all three groups, with the saturation index of the combination group (2.08 +/- 0.17) being the highest. In both groups receiving bile acid therapy, no gallstones were found, and the bile remained unsaturated. For the bile acid-fed groups, both hepatic HMG-CoAR and hepatic cholesterol 7 alpha-hydroxylase activities were reduced (P less than 0.01) when compared to the group fed standard diet and to the grou fed the combination. Thus, a new animal model of cholesterol gallstone formation has been developed in which chenodeoxycholic acid and ursodeoxycholic acid therapy prevented gallstone formation through mechanisms similar to those reported in cholesterol gallstone patients.

A simple radioassay for human urinary kallikrein

We have developed a sensitive, highly selective assay for human urinary kallikrein (HUK) that uses Pro-Phe-Arg-[3H]benzyl-amide as substrate. The substrate was prepared from Pro-Phe-Arg-3-iodo-benzylamide by dehalogenation in 3H2 gas. HUK is measured by its ability to release [3H]benzylamine. The pH optimum is 9.5. Urokinase, plasmin and thrombin do not interfere. The assay can measure as little as 5 ng of HUK in a 15 min incubation at 37 degrees C. Typically, we use 50 microliter of dialyzed urine for HUK assays. Reactions are terminated by adding 0.1 M NaOH, and reaction product is separated from substrate by partitioning with an equal volume of toluene. A sample of the toluene phase is submitted for liquid scintillation counting. As judged by separations obtained on molecular sieve chromatography (Sephacryl), only one urinary enzyme possesses the ability to hydrolyze our substrate. The enzyme MW 45,000, is inhibited by Trasylol but not by soya bean trypsin inhibitor (SBTI). It is reactive with and is inhibited by antibodies prepared against pure HUK.

Preparation of intrinsically-labelled kinins

As part of a program to prepare bradykinin (H-Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg-OH) labelled at high specific radioactivities, we have synthesized three analogs for dehalogenation in tritium gas: [4-Br-Phe5]-bradykinin (BK), [4-Br-Phe8]-BK and [4-Br-Phe5,8]-BK. The analogs were synthesized by the Merrifield solid-phase method and were purified by molecular sieve and partition chromatography. The analogs themselves possess biological activity (as assayed for effects on mean arterial blood pressure and isolated rat uterus). [4-Br-Phe8]-BK was 1.5 to 3 times as active as bradykinin. [4-Br-Phe5,8]-BK was approx. 22% as active as BK and [4-Br-Phe5]-BK was approx. 18% as active. [4-Br-Phe5]-BK was submitted to catalytic dehalogenation with 10% Pd/C and 5% Rh/CaCO3 in H2O and DMF (1:1) plus 10 Ci of 3H2. [4-3H-Phe5]-BK was obtained at 6.7 Ci/mmole in an overall yield of 15%. [4-3H-Phe8]-BK was prepared similarly to yield an intrinsically-labelled peptide with a specific radioactivity of 21 Ci/mmole.

Inhibition by propranolol of bile acid- and PGE1-stimulated camp and intestinal secretion

Three colonic and three ileal loops were prepared in six rabbits pretreated with propranolol (PR) 4 mg./kg. I.V. and in five untreated rabbits. In random order, 1 ml. of either deoxycholic acid (DCA) 6 mM., prostaglandin E1 (PGE1) 20 microgram./ml., or saline was placed in each colonic loop and 1 ml. of either cholera enterotoxin (CE) 10 microgram./ml., PGE1 20 microgram./ml., or saline was placed in each ileal loop. In untreated animals, DCA and PGE1 in the colon and CE and PGE1 in the ileum stimulated (P less than 0.01) adenylate cyclase (AC) and net secretion. In the colon, PR abolished DCA-stimulation of AC and net secretion and decreased PGE1-stimulated AC (P less than 0.01) and net secretion. In conclusion, at the doses and times studied, colonic-AC and net secretion stimulated by PGE1 or DCA was distinguished from small bowel-AC and net secretion stimulated by PGE1 or CE.

Estrogen enhances dietary cholesterol induction of saturated bile in the hamster

The influence of ethinyl estradiol (EE) on the effects of dietary cholesterol on the biliary saturation index and on the rate-limiting hepatic enzymes of cholesterol synthesis, hydroxymethylglutaryl-CoA-reductase, and bile acid synthesis, 7 alpha-hydroxylase, were determined. Four groups of 12 male hamsters were treated for 1 month with EE, 15 micrograms per kg per day, or placebo vehicle administered intraperitoneally and fed either a standard diet, 0.8 mg of cholesterol per g of food, or high cholesterol diet, 2.4 mg of cholesterol per g. The high cholesterol diet increased the saturation index to 1.00 +/- 0.03 (P less than 0.01) from 0.65 +/- 0.02 in untreated hamsters on the standard diet. EE treatment on the high cholesterol diet further increased (P less than 0.01) the saturation index to 1.15 +/- 0.02. The high cholesterol diet decreased (P less than 0.01) hydroxymethylglutaryl-CoA-reductase activity from 308 +/- 16 pmoles per mg per min in untreated hamsters on the standard diet. The addition of EE treatment had no effect on hydroxymethylglutaryl-CoA-reductase activity. The high cholesterol diet increased (P less than 0.01) 7 alpha-hydroxylase activity from 23 +/- 1.0 pmoles per mg per min in untreated hamsters on the standard diet. The addition of EE decreased (P less than 0.01) 7 alpha-hydroxylase activity from that in untreated hamsters on the standard diet. The conclusions are as follows: (1) EE prevented dietary cholesterol-induced stimulation of cholesterol 7 alpha-hydroxylase activity; (2) EE enhanced the ability of dietary cholesterol to induce saturated bile; and (3) gallstone formation in estrogen-treated women may result from impaired metabolism of dietary cholesterol.

Gallstone dissolution by chenodeoxycholic acid and phenobarbital

Gallstone dissolution and biliary lipids were determined and compared in patients receiving either chenodeoxycholic acid (CDC), or CDC and phenobarbital (PB) for 11/2 to 2 years. Among patients with radiolucent gallstones, dissolution occurred in 53% of those receiving CDC alone and in only 25% of those receiving both CDC and PB. No dissolution occurred in 13 other patients with calcified gallstones. Patients with dissolution had a significantly greater molar percentage of CDC and a significantly lower saturation index in bile than those without dissolution. Diarrhea and transiently abnormal liver function tests were the most frequently observed side-effects but only diarrhea necessitated a reduction of the CDC dose. Gallstones recurred following dissolution in one of six patients followed for six months after discontinuation of CDC. In conclusion, PB did not enhance CDC-induced desaturation of bile or gallstone dissolution.

Solitary reticulum cell sarcoma of the uterine cervix with initial cytodiagnosis

A minimally symptomatic elderly woman was discovered to have reticulum cell sarcoma involving the uterine cervix on the basis of cervico-vaginal smears taken in the absence of a visible mass lesion. The diagnosis was confirmed by biopsy, and subsequent clinical and operative staging revealed the tumor to be arising in and confined to the uterine cervix. The cytologic features of reticulum cell neoplasia are repetitive and highly characteristic irrespective of its site of origin.

New substrates for the radioassay of angiotensin converting enzyme of endothelial cells in culture

To develop means of measuring angiotensin converting enzyme of endothelial cells in culture, we have synthesized benzoyl-Phe-Ala-Pro-OH (I), benzoyl-Pro-Phe-Arg-OH (II) and benzoyl-Gly-His-Leu-OH (III), each bearing a 3H-atom on the para-position of its benzoyl moiety. All three of the acylated tripeptides are substrates for the enzyme. Substrate I exhibits the lowest Km (12.5 micrometer) and yields the most sensitive assay: the enzyme of 10(6) cells can be measured in a 30 min incubation at 37 degrees C. Radiolabelled reaction product is separated from substrate by extraction of acidified reaction mixture with an organic solvent, and the rate of formation of product can be quantified by liquid scintillation counting of the organic phase. Substrate III can also be used to measure angiotensin converting enzyme of cells but requires longer incubations (180--240 min) and high salt concentrations (0.75 M Na2SO4). Substrate II is not specific: it is hydrolyzed by more than one enzyme of endothelial cells.

Gallstone prevalence and biliary lipid composition in inflammatory bowel disease

Biliary cholesterol saturation has been correlated with disease variables that might effect bile acid loss in ileitis patients with (N = 9) or without (N = 8) intestinal resection having a defined prevalence of gallstones. In addition, cholesterol saturation was determined in ulcerative colitis patients (N = 7) and gallstone patients (N = 18) as well as in 5 normal controls. Biliary cholesterol saturation in ileitis patients both with and without resection was similar to that in gallstone patients yet the prevalence of gallstones was only 12%. Cholesterol saturation did not correlate with ileal resection nor the extent, duration, or activity of ileitis. Biliary cholesterol saturation was not different in ulcerative colitis patients from that in normal subjects. It is concluded that cholesterol saturation of bile alone does not account for the high prevalence of cholesterol gallstones that has been reported in ileitis patients.

A simple radioassay for angiotensin-converting enzyme

Angiotensin-converting enzyme can be measured by the rate of release of 3H-labelled hippurate from p-[3H]benzoylglycylglycylglycine. The product is separable from the substrate by extraction of acidified reaction mixtures with ethyl acetate. Assay results for human serum angiotensin-converting enzyme can be obtained within 1.5 h of receipt of serum samples. Within the limits tested, the assay appears to be specific. However, interference by hitherto unrecognized enzymes of abnormal sera must be ruled out.

Feasibility of low-dose and intermittent chenodeoxycholic acid therapy of gallstones

Chenodeoxycholic acid, by reducing the concentration of biliary cholesterol relative to that of bile acid and phospholipid, dissolves cholesterol gallstones. This bile acid, however, has potential dose-related hepatotoxicity and causes dose-related diarrhea. Therefore, the feasibility of low-dose and intermittent therapy was assessed by studying the induction and persistence of chenodeoxycholic acid-induced biliary lipid changes. Biliary lipid composition with each of 3 doses of chenodeoxycholic acid was determined in bile samples obtained by cholecystokinin-stimulated duodenal drainage before, after one week and one month of treatment, and up to 9 weeks after discontinuation of treatment. The lowest dose that significantly reduced the relative concentration of biliary cholesterol was 250 mg/day. A significant reduction occurred one week after initiation of treatment and was maintained for 9 weeks following discontinuation of treatment. Thus, clinical trials on low-dose and intermittent chenodeoxycholic acid therapy for gallstone prophylaxis or dissolution are warranted.

Lymphocyte and fibroblast chalones: some chemical properties

Experiments with lymphocyte and fibroblast chalones indicate that they are complexed strongly with RNA in tissue extracts; have a molecular weight of less than 10,000 and more than 1,000 daltons, and probably about 5,000 daltons; are strongly cationically charged; and contain mannose and perhaps other carbohydrates.

Dietary cholesterol affects chenodeoxycholic acid action on biliary lipids

Chenodeoxycholic acid (CDC) decreases biliary saturation and dissolves gallstones in one-half of the treated patients. Dietary cholesterol also affects biliary lipids and is a possible factor explaining unsuccessful CDC therapy. The aim of this investigation was to study the effect of high and low dietary cholesterol on the CDC-induced decrease of biliary saturation and activity of hepatic hydroxymethylglutaryl coenzyme A reductase (HMG-CoAR). Seventy two hamsters in six groups were fed for 1 month one of three diets: 0.8 mg of cholesterol per g of food, 2.4 mg of cholesterol per g, or cholesterol-free. On each diet hamsters received no CDC or CDC 30 mg per kg per day. When animals were killed, biliary lipids were determined and the activity of hepatic HMG-CoAR was assayed. CDC administration decreased the saturation index (SI)(P less than 0.01) in hamsters on the high cholesterol and standard diets but not on the cholesterol-free diet. The SI in CDC-treated hamsters on the high cholesterol (0.78 +/- 0.03) and cholesterol-free (0.68 +/- 0.02) diets were greater (P less than 0.02) than in CDC-treated hamsters on the standard diet (0.48 +/- 0.03). CDC decreased (P less than 0.01) HMG-CoA reductase activity on each diet. In comparison to HMG-CoAR activity (190 +/- 7.6 pmoles per mg per min) in CDC-treated hamsters on the standard diet, the activity in CDC-treated hamsters on the high cholesterol diet (176 +/- 5.8 pmoles per mg per min) was decreased ( less than 0.05), whereas the activity on the cholesterol-free diet (495 +/- 11.5 pmoles per mg per min) was greater (P less than 0.01). It is concluded that: (1) dietary cholesterol is necessary for optimum CDC inhibition of HMG-CoAR; (2) high cholesterol and cholesterol-free diets prevent maximum CDC decrease of the biliary saturation index; (3) dietary cholesterol alterations may therefore be one cause of the failure of CDC dissolution of gallstones.

Squamous carcinoma arising in benign cystic teratoma of the ovary: a report of four cases and review of the literature

Four cases of squamous carcinoma arising in benign cystic teratoma of the ovary are presented, with a detailed correlation of clinical, operative and pathological findings with prognosis. Confinement of tumor to the ovary, with an intact ovarian capsule, is the most important prognostic factor since patients wih extracapsular extension succumb to their disease within 2 years. The literature dealing with this subject is reviewed.

Effect of propranolol on bile acid- and cholera enterotoxin-stimulated cAMP and secretion in rabbit intestine

Stimulation of net secretion by deoxycholic acid (DCA) in the colon and by cholera enterotoxin (CE) in the jejunum is mediated by cAMP. Propranolol (Pr) inhibits adenylate cyclase (AC) activity and net secretion induced by bile acid in the colon. The aim of this study was to assess the organ specificity of DCA and CE as well as the selectivity of Pr inhibition. Three colonic and three jejunal loops were prepared in each of 8 rabbits treated intravenously with Pr, 4 mg per kg, 1/2 hr before loop construction and in each of 10 untreated control rabbits. One milliliter of DCA, 6 mM, CE, 10 mug per ml, or heat-inactivated CE or 0.9% NaCl, as basal controls were injected in random order into each of the loops. The volume of luminal fluid and mucosal AC were measured in each intestinal loop 5 hr later. DCA in the colon stimulated AC 2-fold (P less than 0.01) and luminal fluid 15-fold (P less than 0.01). CE in the jejunum stimulated AC 2.3-fold (P less than 0.01) and luminal fluid 9-fold (P less that 0.01). No significant effects on volume or AC occurred in response to CE in the colon or to DCA in the jejunum. Pr pretreatment completely prevented the stimulation of AC and luminal fluid by DCA in the colon but did not affect the action of CE in the jejunum of the same animals. Thus, DCA and CE are organ-specific stimulants of cAMP systems, and Pr is a selective inhibitor of certain inducers of cAMP and net secretion.

Inhibition by propranolol of bile acid stimulation of rabbit colonic adenylate cyclase in vitro

Bile acids, especially unconjugated deoxycholic acid, cause diarrhea by inducing colonic mucosal secretion of water and electrolytes. This effect has been shown to be mediated by adenylate cyclase (AC). Propranolol, a beta-adrenergic blocking agent which inhibits AC, may then prevent this action of bile acids on colonic mucosa. The aim of this study was to determine the effect of bile acids, catecholamines, and propranolol on AC activity in colonic mucosa. The in vitro effects of deoxycholic acid, taurocholic acid, NaF, epinephrine, norepinephrine, and propranolol on AC in rabbit colonic mucosa were determined. NaF, 10(-4) M, increased AC activity to 220% of control (P less than 0.01). Deoxycholic acid, 10(-4) M, increased AC activity to 178% of control (P less than 0.01). Lesser but significant (P less than 0.01) stimulation of AC occurred at both higher and lower concentrations of deoxycholic acid, with no effect at 10(-10) M. Taurocholic acid, 10(-4) M, and epinephrine and norepinephrine, 10(-2) M, 10(-4) M, 10(-6) M, and 10(-8) M, had no effect on AC. Propranolol, 10(-6) M, caused a 60% decrease (P less than 0.01) in the stimulated AC activity induced by 10(-4) M deoxycholic acid. Propranolol, 10(-4) M, decreased basal AC by 30% (P less than 0.01).

IN CONCLUSION

(1) Deoxycholic acid, but not taurocholic acid, epinephrine, or norepinephrine, stimulates colonic AC activity. (2) Propranolol inhibited this deoxycholic acid stimulation of AC. (3) Catecholamines are not intermediaries in this action of propranolol on colonic mucosal AC activity.

Propranolol inhibits adenylate cyclase and secretion stimulated by deoxycholic acid in the rabbit colon

Bile acids cause diarrhea by inducing colonic secretion, probably mediated through the cyclic AMP system. The aim was to determine the effects of an adenylate cyclase inhibitor, propranolol, on deoxycholic acid (DCA) stimulation of net secretion and the cyclic AMP system in the colon. In each of 30 New Zealand white rabbits, 0.9% NaC1 as control and 6 mM and 8 mM DCA were injected in random sequence into three colonic loops in situ. Propranolol, 4 mg per kg was administered intravenously to 12 of the 30 rabbits 1/2 hr before preparation of the loops, i.e., 5 1/2 hr before the rabbits were killed. In the 18 untreated animals, 6 and 8 mM DCA significantly stimulated colonic net secretion and mucosal adenylate cyclase activity; 6 mM DCA caused no change in mucosal phosphodiesterase activity, whereas 8 mM DCA caused a 25% decrease (P less than 0.01). In propranolol-treated animals compared to untreated animals, the volume of luminal fluid in controls was not different, with 6 mM DCA it was 88% less (P less than 0.01), and with 8 mM DCA it was 45% less (P less than 0.01); adenylate cyclase activity in controls was 43% less (P less than 0.01), with 6 mM DCA it was 67% less (P less than 0.01), and with 8 mM DCA it was 65% less (P less than 0.01); phosphodiesterase activity in controls and with 6 mM DCA was not different and with 8 mM DCA it was 38% greater (P less than 0.02). In conclusion, propranolol prevented DCA stimulation of colonic net secretion and inhibited the cyclic AMP system. Propranolol, therefore, warrants investigation as therapy for diarrhea caused by bile acids in the colon.

Localization of angiotensin converting enzyme (kininase II). I. Preparation of antibody-hemeoctapeptide conjugates

Antibodies to pig lung angiotensin converting enzyme (kininase II) were conjugated to a heme-octapeptide (8-microperoxidase, 8-MP) derived from cytochrome c. 8-MP, which has only one reactive amine, was coupled to antibody in a two-step procedure using a bifunctional active ester, bis-succinyl succinate. In the first-step, 8-MP-succinyl succinate, a stable compound which can be stored. In a second step, the remaining active ester was used for coupling to reactive amines of the antibody. The conjugate consists of 1.6-2.3 8-MP moieties per antibody. Using these procedures, the formation of complex polymers is avoided. Each molecule of conjugate possesses both immunoreactivity and peroxidatic activity. The conjugate has been used to localize angiotensin converting enzyme along the plasma membrane and associated caveolae of pig aortic endothelial cells in culture.

Cardiac glycogen in long-evans rats: diurnal pattern and response to exercise

The 24-h pattern of cardiac glycogen was determined in normally active, caged male Long-Evans rats. Relatively small fluctuation was observed during a 24-h cycle with maximal difference between mean values ranging from 3.41 +/- 0.28 (dark room) to 5.15 +/- 0.19 (light room) mg glycogen/g wet wt heart, suggesting that the substantial diurnal variation of cardiac glycogen reported in Wistar rats is not a universally observed phenomenon. Cardiac glycogen during and following a single bout of moderate running was compared to a bout of strenuous running in fed male Long-Evans rats. Moderate continuous running at 20 m/min for 30 min did not decrease cardiac glycogen below the average control level (4.09 +/- 0.10 mg glycogen/g heart) but did cause a short period of supercompensation, which reached a peak of 6.27 +/- 0.19 mg/g heart at 2 h postexercise. Strenuous running in bouts at 30 m/min over a 2-h period for a distance of 1,413 m caused a significant decrease in cardiac glycogen to 2.66 +/- 0.20 mg/g heart followed by an extended period of supercompensation, which reached a peak of 9.01 +/- 1.41 mg/g heart at 4 h postexercise and remained significantly elevated during the next 13 h. Thus, the severity of exercise in normal, fed rats determines not only the extent of cardiac depletion, but also the supercompensation pattern of glycogen repletion following exercise.