Relationship of short-term verbal memory to the need for hyperbaric oxygen treatment after carbon monoxide poisoning

It has long been known that carbon monoxide (CO) poisoning has a spectrum of effects on cognitive functioning, including memory, perception, and attention. The current study reports the investigation of the effects of CO poisoning on short-term verbal memory, both rote and context aided. Impairment was measured before and after hyperbaric oxygen (HBO) treatment. Twenty-six patients who had been admitted for emergency treatment after exposure to significant CO poisoning were tested using a measure of short-term recall for word lists with no or varying degrees of internal context-aided structure. Impairment of context-aided memory (but not rote memory) has been previously reported to be associated with low relative frontal volume in psychiatric patients. Carbon monoxide poisoning was significantly associated with impairment of context-aided memory, with the degree of pretreatment impairment predicting the number HBO treatments judged to be necessary on the basis of clinical monitoring of the patient. In patients with poisoning of moderate severity, pretreatment performance in context-aided memory improved after the first HBO treatment. The implications of these findings for the effects of CO poisoning on frontal area function are discussed. The memory measure used in this study appears to have considerable potential usefulness in the clinical assessment of the severity of CO poisoning in patients treated in an emergency setting.

Two separate regions in the genome of the tobacco etch virus contain determinants of the wilting response of Tabasco pepper

Infection of Tabasco pepper by the tobacco etch virus (TEV) typically causes wilting associated with root necrosis. However, a strain of TEV, designated TEV nonwilting (TEV NW), is able to infect Tabasco pepper plants but does not cause wilting. In order to locate the genetic determinants responsible for the wilting response, a full-length cDNA clone of TEV NW from which infectious transcripts can be derived was made. A number of chimeric constructs were prepared by substituting cDNA fragments between TEV HAT (which causes wilting) and TEV NW clones. This approach was used to identify two wilting determinants in TEV HAT: one encompasses the 3' one-third of the P3 encoding region; the other spans the 3' end of the CI, the 6-kDa protein, and the 5' end of the VPg-NIa coding regions. Substitutions of both these TEV NW fragments into TEV HAT resulted in infection but not wilting of Tabasco pepper, while the replacement of either of the fragments alone did not alter the wilting response. This indicates that both TEV NW regions contain determinants necessary but not sufficient to alter the wilting response and that both must be present in order to avoid the wilting response. There was no difference between the in vitro transcription-translation products derived from constructs containing these regions from TEV HAT and TEV NW.

Sch 54445: a new polycyclic xanthone with highly potent antifungal activity produced by Actinoplanes sp

A novel antifungal agent, Sch 54445, was isolated from the fermentation broth of an Actinoplanes species. Sch 54445 was identified as a polycyclic xanthone related to the albofungin family of compounds on the basis of analyses of spectroscopic data. As a broad-spectrum antifungal agent, Sch 54445 exhibits highly potent activities against various yeasts and dermatophytes with MIC values approximately 0.00038 microgram/mL.

Effect of chronic endogenous hypergastrinaemia on pancreatic growth and carcinogenesis in the hamster

BACKGROUND

To examine the effect of gastrin on spontaneous and induced pancreatic carcinogenesis in the hamster.

METHODS AND RESULTS

Two sets of experiments were carried out, one involving long term hypergastrinaemia and one involving cancer induction during hypergastrinaemia. The effect of hypergastrinaemia accomplished by gastric fundectomy was studied for eight months. Neither fundectomised hamsters nor sham operated controls developed premalignant or malignant pancreatic lesions. In the fundectomy group, the mean pancreatic weight, total protein content, and DNA content was increased by 28%, 25%, and 25% respectively. No such increases were found in fundectomised animals receiving a cholecystokinin-B receptor antagonist during the last 24 days of the experiment. In the cancer induction study, the effect of fundectomy on N-nitrosobis(2-oxopropyl) amine induced pancreatic carcinogenesis was studied for three months. There were no significant differences in the incidence or [3H]-thymidine labelling index of focal pancreatic lesions between fundectomised and sham operated control animals.

CONCLUSIONS

Fundectomy with chronic hypergastrinaemia induces pancreatic hypertrophy, but does not enhance N-nitrosobis (2-oxopropyl)amine induced pancreatic carcinogenesis in the hamster. The increases in growth were inhibited by a cholecystokinin-B receptor antagonist, indicating that the trophic effect of fundectomy is mediated by gastrin.

Chronic endogenous hypercholecystokininemia promotes pancreatic carcinogenesis in the hamster

In order to examine the effect of cholecystokinin on spontaneous and induced pancreatic carcinogenesis in the hamster, two sets of experiments were carried out, one involving long-term hypercholecystokininemia and one involving cancer induction during hypercholecystokininemia. The effect of hypercholecystokininemia, induced by pancreaticobiliary diversion (PBD), was studied for 8 months. Neither PBD animals nor sham-operated controls developed premalignant or malignant pancreatic lesions. However, in the PBD group the mean pancreatic weight, total protein content and DNA content were increased by 30, 29 and 27% respectively. No such increases were found in PBD animals receiving a cholecystokinin-A receptor antagonist during the last 24 days of the experiment. In the cancer induction study, the effect of PBD on N-nitrosobis(2-oxopropyl)amine-induced pancreatic carcinogenesis was studied for 3 months. Putative premalignant pancreatic lesions were diagnosed in all PBD hamsters and in four of 15 sham-operated controls. Pancreatic ductular carcinoma in situ was only found in PBD animals. The [3H]thymidine labeling index of the pancreatic lesions was significantly higher in the PBD group than in the controls. No such increase was observed in PBD animals receiving a cholecystokinin-A receptor antagonist during the last 5 days of the experiment. It is concluded that chronic endogenous hypercholecystokininemia promotes early phase pancreatic carcinogenesis, but does not per se cause development of premalignant or malignant pancreatic lesions in the hamster.

Unsafe abortions: methods used and characteristics of patients attending hospitals in Nairobi, Lima, and Manila

Using quantitative and qualitative data, the authors present selected characteristics of 626 women who reported complications of induced abortion in five hospitals: one in Nairobi, two in Lima, and two in Manila. Although there are some similarities, the findings show some marked differences in demographic characteristics. In Nairobi nearly all respondents were single, nulliparous, and 25 years or younger; in Lima and Manila most were either married or in union, usually aged 25 years or older and had at least 1 child. There was evidence of repeat abortions, especially in Nairobi where 26% had had at least one previous abortion. Access to safe abortions is severely restricted and is obtained through a secret referral system. A list of potentially hazardous local abortifacients range from the drinking of strong Kenyan tea to dangerous practices such as insertion of sharp objects into the uterus or drinking chemicals and toxic substances.

The national distribution of Certified Registered Nurse Anesthetists across metropolitan and nonmetropolitan settings

The purpose of this study is to describe the metropolitan and nonmetropolitan distribution of Certified Registered Nurse Anesthetists actively practicing across the United States. More than 3,000 counties of the United States were categorized according to degree of urbanization by utilizing the rural-urban continuum codes for metropolitan and nonmetropolitan counties developed within the U.S. Department of Agriculture. Zip code information was used to locate all actively practicing CRNAs by county of residence. Applying the rural-urban continuum codes to this database revealed a descriptive national distribution of CRNAs across geographical areas. Data show that 81.3% (18,086) of CRNAs reside in metropolitan counties and that 18.7% (4,182) reside in nonmetropolitan areas. The greatest number of CRNAs (8,519) are found in central counties of metropolitan areas of one million population or more. The lowest number of CRNAs (90) are found in completely rural counties of fewer than 2,500 urban population adjacent to a metropolitan area, and 160 CRNAs reside in counties of fewer than 2,500 population not adjacent to a metropolitan area. Differences in age, gender distribution, educational credentials, and population ratios are also noted between metropolitan and nonmetropolitan CRNAs.

The basic domain/leucine zipper protein hXBP-1 preferentially binds to and transactivates CRE-like sequences containing an ACGT core

The transcription factor hXBP-1 belongs to the family of basic region/leucine zipper (bZIP) proteins and interacts with the cAMP responsive element (CRE) of the major histocompatibility complex (MHC) class II A alpha, DR alpha and DP beta genes. However, the developmental expression of hXBP-1 as revealed by in situ hybridization in mouse embryos, has suggested that it interacts with the promoter of additional genes. To identify other potential target genes of this factor, we performed binding site selection experiments with recombinant hXBP-1 protein. The results indicated that hXBP-1 binds preferably to the CRE-like element GAT-GACGTG(T/G)NNN(A/T)T, wherein the core sequence ACGT is highly conserved, and that it also binds to some TPA response elements (TRE). hXBP-1 can transactivate multimers of the target sequences to which it binds in COS cells, and the level of transactivation directly correlates with the extent of binding as observed in gel retardation experiments. One target sequence that is strongly bound by hXBP-1 is the 21 bp repeat in the HTLV-1 LTR, and we demonstrate here that hXBP-1 can transactivate the HTLV-1 LTR. Further, the transactivation domain of hXBP-1 encompasses a large C-terminal region of the protein, containing domains rich in glutamine, serine and threonine, and proline and glutamine residues, as shown in transient transfection experiments using hXBP-1-GAL4 fusion proteins and a reporter gene under the control of GAL4-binding sites.

Inhibition of c-fos proto-oncogene induction by Sch 52900 and Sch 52901, novel diketopiperazine produced by Gliocladium sp

Sch 52900 (1) and Sch 52901 (2), two new inhibitors of c-fos proto-oncogene induction, have been isolated from the fermentation of broth of the fungal culture (SCF-1168), Gliocladium sp. Along with compounds 1 and 2, a known compound verticillin A (3) was also obtained from the culture. Structure elucidation of 1 and 2, accomplished by analysis of spectral data in comparison with the data of 3, revealed both 1 and 2 were found to be closely related to the verticillin family of diketopiperazines. All three compounds prevented serum-stimulated transcription of the human c-fos promoter, using a fos/lac Z reporter gene assay, with IC50 values of 1.5, 18 and 0.5 microM of 1, 2 and 3, respectively. Northern analysis revealed the exposure of cells to compound 3 causes inhibition of both phorbol ester-induced c-fos induction of serum-induced JE induction in the absence of inhibiting RNA synthesis, as measured by [3H]uridine incorporation. There results suggest that this class of compounds exerts antitumor activity by blocking a signal transduction pathway that is common to and necessary for the induction of at least a subset of immediate early genes involved in cell proliferation.

Effect of endogenous hypergastrinemia on gastrin receptor expressing human colon carcinoma transplanted to athymic rats

BACKGROUND & AIMS

The effect of endogenous hypergastrinemia on growth of human colon carcinoma is not known. Our aim was to study the growth of human colon carcinoma in an animal model with endogenous hypergastrinemia.

METHODS

Human colon carcinoma was transplanted to the colon of 40 athymic rats. Of these, 25 underwent gastric fundectomy to accomplish endogenous hypergastrinemia, and 15 were sham operated to serve as controls. The duration of the study was 8 weeks. During the last week, 12 fundectomized animals received a gastrin (cholecystokinin B) receptor antagonist. Metaphase arrest index, local invasion, and distant spread of the tumor were investigated. Expression of gastrin and cholecystokinin B receptor messenger RNA was examined by reverse-transcription polymerase chain reaction.

RESULTS

Tumor spread by direct extension outside the colon was observed in all animals, and liver metastases were observed in 10 of the 25 fundectomized animals. Sham-operated animals showed none of these features. The metaphase arrest index of the tumor did not differ between fundectomized animals given the cholecystokinin B receptor antagonist and sham-operated animals, whereas it was significantly increased in fundectomized animals not given the antagonist. The tumor expressed both gastrin and cholecystokinin B receptor messenger RNA.

CONCLUSIONS

The results indicate that endogenous hypergastrinemia may promote proliferation and spread of human colon carcinoma expressing cholecystokinin B receptor.

Effects of graded glutamine intake on liver protein metabolism following partial hepatectomy

OBJECTIVE

To elucidate whether glutamine can influence the rate of regeneration and protein metabolism in regenerating liver.

DESIGN

Liver regeneration rate, protein content and synthesis were measured in rats 7 days after a liver resection or sham operation. After the operation, the rats were fed three elementary isonitrogenous diets, one without and two including different levels of glutamine.

METHODS

Fifty-six rats were randomly assigned to either sham operation or liver resection. After the operation, they received an isonitrogenous, isocaloric elementary diet with a glutamine content of 0, 2 or 4%. The resected part of the liver was weighed and analysed for DNA and protein content. Seven days later, hepatic protein synthesis was measured by the flooding method using L-[3H]-phenylalanine, and the liver was analysed for DNA, RNA and protein content.

RESULTS

The regeneration rate was higher in the group receiving 2% glutamine but not in the group receiving 4% glutamine than in the 0% group. Total protein content was increased in regenerating liver in the 2 and 4% glutamine groups compared with the 0% group. Protein synthesis was higher 7 days after liver resection than in sham-operated rats. In the 2% group there was a tendency towards increased protein synthesis compared with the 0% group.

CONCLUSION

A diet with normal glutamine content improved liver regeneration rate, total protein content and protein synthesis in regenerating liver, but an excess of glutamine did not enhance this effect.

Discrepancy in T cell clonal expansions in synovial fluid and peripheral blood from rheumatoid arthritis patients

Rheumatoid arthritis (RA) is an autoimmune disease involving the synovial membrane of peripheral joints. T cells specific for self antigens may play a critical role. Identification of T cell receptors (TCR) of such specific T cell clones is very important for treatment, prevention and identification of relevant autoantigens. To identify specific T cells, TCR V beta family repertoire and the clonal expansion of T cells were analyzed in this study. The percentage of V beta 5+ or V beta 8+ cells in the synovial fluid mononuclear cells (SFMCs) was similar to that in the peripheral blood mononuclear cells (PBMCs). However, the percentage of DR+ T cells in the SFMCs was higher (p < 0.01). Analyzing the clonality of T cells in 8 V beta families (V beta 1, V beta 5, V beta 8, V beta 14, V beta 16, V beta 17, V beta 18, V beta 20), clonal expansions in CD8+ T cells from the SFMCs were found more frequently than in the PBMCs. The patterns of clonal expansions were discrepant between the SFMCs and the PBMCs even in the same patient, which suggests several inflamed tissue specific T cell clonal expansions in the SFMCs. These T cell clones might be activated by autoantigens which are not identified yet and responsible for the RA pathogenesis.

Mutational analysis of the coat protein N-terminal amino acids involved in potyvirus transmission by aphids

The nature of the amino acids in the N-terminal 'DAGX' motif of the coat protein of tobacco vein mottling virus (TVMV) that have a direct effect on aphid transmissibility of the virion were further defined by site-directed mutagenesis. In the first position of the DAGX motif, Asp or Asn are required for aphid transmissibility. In the second position, the nonpolar residue Ala, but not the nonpolar Gly or Val or the polar Thr and Ser, is compatible with transmissibility. In the third position, the small, neutral, nonpolar Gly appears to be critical; even substitution of Ala, with a minimal side-chain, drastically reduces transmissibility. Although the amino acid following the DAG sequence is not highly conserved among potyviruses, the presence of an acidic Glu or Asp residue at this position in the TVMV coat protein drastically reduces or abolishes aphid transmissibility. An attempt was made to test the hypothesis that trypsin cleavage of the N terminus is involved in the aphid inoculation process by destroying a trypsin cleavage site downstream from the DAGX motif. While the predicted decrease in transmission occurred from infected plants, there was no effect on the transmission of purified virus. Of the 23 mutations in the DAGX region of TVMV reported here and previously, only two, substitutions of Lys and Arg for Asp, had a detectable adverse effect other than on aphid transmissibility. These, and perhaps other, residues near the N terminus function in some phase of the TVMV life cycle, in addition to aphid transmission.

Transesophageal indirect atrial pacing for open-heart surgery in children

BACKGROUND

Transesophageal atrial pacing (TAP) has been successfully applied for clinical use for more than 30 years. Not only for cardiac pacing, or diagnosis and treatment of rhythmic disturbance but also for assessing the presence and severity of coronary artery disease and maintaining adequate heart rate can TAP provide satisfactory effect. In this study we applied TAP on children undergoing the cardiac surgery to evaluate its efficacy and side effects during such major surgery.

METHODS

Twenty-four children (15 M and 9 F) undergoing open-heart surgery with informed consents were included in this study. After induction of anesthesia the bipolar pacing electrode (Tapcath, Arzco Medical Electronics) was inserted into esophagus through the nose until the ideal site for atrial pacing was found by monitoring the esophageal ECG lead (lead I), and then initiation of atrial pacing was performed by applying the transesophageal cardiac stimulator (Arzco Medical Electronics). Continuous ECG, arterial blood pressure and central venous pressure (CVP) were simultaneously monitored and recorded. Patient's height, inserted length of the pacing electrode, current and pulse duration for effective atrial pacing were also recorded.

RESULTS

The effective rate for initiating sinus tachycardia (atrial capture) by applying TAP was 79.2% (19/24) in our study. For effective atrial pacing the average current was 11.6 +/- 2.4 mA, the average stimulus pulse duration was 4.8 +/- 1.0 ms, and the average inserted length of bipolar electrode was 19.1 +/- 2.2 cm.

CONCLUSIONS

TAP method can be applied satisfactorily in children undergoing cardiac surgery. If urgent cardiac pacing must be applied in these patients TAP would be a choice.

Novel ketoepoxides block phospholipase D activation and tumor cell invasion

The functional significance of phospholipase D (PLD) could most easily be investigated using selective inhibitors. We have isolated a family of fungal metabolites, ketoepoxides, that inhibit chemotactic peptide (formyl-Met-Leu-Phe)-stimulated PLD activation and superoxide generation in granulocytes in the low micromolar range (SCH 49210 having an IC50 of 1.6 microM). Unlike receptor-mediated PLD activation, ketoepoxides were poor inhibitors of phorbol ester-induced PLD activity in granulocytes (IC50 = 43 microM for SCH 49210). Ketoepoxides did not inhibit platelet-derived growth factor-stimulated PLD activity in fibroblasts at up to 50 microM. We also tested the effect of ketoepoxides on in vitro epidermal growth factor receptor and neu tyrosine kinase activities. SCH 49210 (and 49209) did not inhibit the tyrosine kinases at up to 100 microM. These results suggest that ketoepoxides do not inhibit PLD activation due to effects on tyrosine kinase activity. fMLP-induced phospholipase A2 (PLA2) activation is also inhibited by ketoepoxides in the low micromolar range (SCH 49210 having an IC50 of 3.2 microM), but the ketoepoxides were poorer inhibitors of Ca2+ ionophore A23187-induced PLA2 (SCH 49210 having an IC50 of 83 microM). As a measure of phospholipase C (PLC) activity, the generation of inositol-1,4,5 triphosphate in thrombin-stimulated platelets was measured. The ketoepoxides did not inhibit PLC activation indicating that, unlike the aminosteroid U73122, ketoepoxides exhibit some selectivity among receptor-linked phospholipases. The ketoepoxides were also effective inhibitors of tumor cell invasion, as measured by penetration of HT1080 human fibrosarcoma cells into a reconstituted basement membrane matrix. Interestingly, both PLD inhibition and anti-tumor invasion activity correlate closely. These ketoepoxides are, therefore, potential anti-metastatic compounds and may be useful probes to study the role of PLD in cell function.

Endogenous hypercholecystokininemia, but not aspirin, reduces the gallstone incidence in the hamster model

BACKGROUND

Studies in humans and rodents indicate that gallstone development may be prevented by inhibiting gallbladder mucus hypersecretion with non-steroidal anti-inflammatory drugs or by preventing stasis of gallbladder bile with administration of cholecystokinin.

METHODS

The effect of oral aspirin and pancreaticobiliary diversion with endogenous hypercholecystokininemia on crystal and gallstone formation was studied in Syrian golden hamsters fed a lithogenic diet for 8 weeks.

RESULTS

None of the control animals fed a normal diet developed gallstones or crystals in gallbladder bile. Gallstones developed in 67% of the animals fed a lithogenic diet only. The gallstone prevalence did not differ significantly in animals on a lithogenic diet and a daily aspirin dose of 6 mg/kg (gallstone prevalence, 60%) or 100 mg/kg (gallstone prevalence, 70%), whereas it was significantly lower in animals with endogenous hypercholecystokininemia on a lithogenic diet (gallstone prevalence, 29%). The prevalence of crystals in gallbladder bile did not differ significantly between any of the experimental groups.

CONCLUSIONS

It is concluded that in hamsters on a lithogenic diet, aspirin does not prevent gallstone formation, whereas endogenous hypercholecystokininemia reduces the prevalence of stones without affecting the occurrence of crystals in gallbladder bile.

Effects of gastric fundusectomy and antrectomy on gallbladder epithelial proliferation in the hamster

BACKGROUND

Exogenous administration of cholecystokinin or its analog cerulein induces epithelial hyperplasia in the mouse gallbladder. The effects on the gallbladder of resectional surgery of the stomach with hormonal consequences are not known.

METHODS

The effects of gastric fundusectomy and antrectomy on proliferation and growth of the gallbladder epithelium were studied in male Syrian golden hamsters during periods of 5 and 25 days. Sham-operated animals served as controls.

RESULTS

Basal plasma gastrin concentrations were significantly increased after fundusectomy and significantly decreased after antrectomy, whereas basal plasma cholecystokinin concentrations were not significantly affected. Five days after fundusectomy, there was a significant increase in the tritiated thymidine DNA labeling index of gallbladder epithelial cells. On day 25, the gallbladder weight and total number of epithelial cells were significantly increased after fundusectomy. Antrectomy significantly decreased the gallbladder weight on day 25, whereas the labeling index and total number of epithelial cells were not significantly affected on days 5 and 25.

CONCLUSIONS

These results suggest that gastric fundusectomy at least transiently induces gallbladder epithelial hyperplasia and hypertrophy in the hamster. Although achlorhydria and hypergastrinemia are prominent features, the actual mechanism behind this effect of fundusectomy on the gallbladder needs further clarification.

Colonic mucosal proliferation after pancreaticobiliary diversion in the hamster

The effect of pancreaticobiliary diversion (PBD) on the colonic mucosa was studied in hamsters over 5, 10, and 24 days. Sham-operated animals served as controls. At all three time intervals, experimental animals had increased plasma cholecystokinin concentrations and decreased gastrin concentrations. Five days after PBD, there was an increase in scintigraphically measured [3H]thymidine incorporation into colonic tissue. Correspondingly, there was an increase in the [3H]thymidine DNA labeling index of goblet cells in the colonic mucosa. The total number of cells in the colonic crypt columns were significantly increased on days 5, 10 and 24. Whether this proliferative response in the colon is due to increased release of cholecystokinin, enteroglucagon, other aberrations of hormones or growth factors, or simply an increased bile load on the colonic mucosa remains to be clarified. Such further studies may reveal an alternative animal model for studies on risk factors in colonic carcinogenesis.

Ultrahigh repetition rate picosecond pulses from a passively mode-locked neodymium glass laser by solid-state saturable dye films

Ultrashort pulses with ultrahigh tunable repetition rates up to 50 GHz are produced by the use of a solid-state saturable absorber film of polymethine dyes in a polymer matrix to mode lock a neodymium glass laser. The energy and the pulse duration of the ultrashort pulses and the stability of the train are measured. The shortest duration pulses produced are ~4 ps with no noticeable change in the optical properties of solid-state dye films after several hundred shots of operation.

Pancreatic hypertrophy with acinar cell nodules after longterm fundectomy in the rat

The effect of gastric fundectomy with hypergastrinaemia on the pancreas in rats was studied for 14 months. Rats with hypercholecystokininaemia that had had a pancreaticobiliary diversion (PBD) operation and sham operated rats served as controls. Fundectomised rats showed a significant increase in pancreatic weight and total DNA and protein content compared with sham operated rats. DNA flow cytometry showed a significantly higher ratio of tetraploid to diploid nuclei in pancreatic tissue after fundectomy than after sham operation. Mean values of all these variables were significantly lower after fundectomy than after PBD. Acidophilic atypical acinar cell foci of the pancreas were diagnosed in both fundectomised and PBD operated rats, but not in sham operated controls. The volume density and 3H-thymidine labelling index of the acidophilic atypical acinar cell foci were significantly lower after fundectomy than after PBD. Changes consistent with pancreatic adenoma were diagnosed in the PBD group only. In conclusion, fundectomy lasting about half of the life span in rats causes pancreatic hyperplasia and hypertrophy, as well as development of acidophilic atypical acinar cell foci. Although hypergastrinaemia is a prominent feature, it may not be the only factor responsible for this pancreaticotrophical effect of fundectomy.

Effects of pancreaticobiliary diversion and gastric fundectomy on azaserine-induced pancreatic carcinogenesis in the rat

The effects of pancreaticobiliary diversion (PBD) and gastric fundectomy on the pancreas in azaserine-treated rats were studied over 14 months. Sham-operated azaserine-treated animals served as controls. A significant increase in pancreatic weight and total DNA and protein content was found in PBD-operated and fundectomized animals. DNA flow cytometry showed a significantly increased ratio of tetraploid to diploid cells in pancreatic tissue in both experimental groups. Mean values of all these variables were significantly higher after PBD than after fundectomy. Acidophilic atypical acinar cell foci of the pancreas were observed in all of the experimental and 75% of the control animals. The volume density of these foci was significantly higher in each experimental group than in the controls. The volume density, radioactive thymidine labeling index, and mitotic index of the foci were significantly higher after PBD than after fundectomy. Changes consistent with pancreatic adenoma were diagnosed in the PBD group only. It is concluded that not only PBD with endogenous hypercholecystokininemia, but also fundectomy with endogenous hypergastrinemia lasting about half of the life span in rats, induces pancreatic hypertrophy and enhances the development of precancerous pancreatic changes after azaserine treatment. In comparison with PBD, fundectomy caused less pronounced changes and no observable neoplasia.

A novel class of platelet activating factor antagonists from Phoma sp

Four novel platelet activating factor (PAF) antagonists, Sch 47918, Sch 49026, Sch 49027 and Sch 49028, were isolated from the fermentation broth of the fungal culture, Phoma sp. (ATCC 74077). The structures of these compounds were elucidated by spectroscopic methods. The structure and stereochemistry of the first isolated component, Sch 47918, were confirmed by single crystal X-ray diffraction analysis. Sch 49028, the most active component, was found to inhibit PAF-induced human platelet aggregation in vitro with an IC50 of 1.26 microM. However, this compound was inactive in vivo at 5 mg/kg, iv against PAF-induced bronchospasm in guinea pigs.

Tidal volume peritoneal dialysis versus intermittent peritoneal dialysis

In a 12-week crossover study we assessed the effect of tidal volume peritoneal dialysis (TVPD) on serum chemistry, patient well-being, appetite and sleep, blood pressure, and body weight period and compared it with the effect of intermittent peritoneal dialysis (IPD) on these same parameters over a similar period. We used similar volumes of dialysis solutions per exchange and session, and the exchanges were of the same duration in each session. There were 12 patients (6 males, 6 females) with a mean age of 76 years (range 61-88 years), and mean duration of peritoneal dialysis 49 months (range 20-148 months). Five patients started with TVPD and switched to IPD after 3 months; the remaining 7 patients started with IPD and switched to TVPD for the next 3 months. No differences were seen between TVPD and IPD in any of the measured parameters: body weight, appetite, sleep, and well-being by self-assessment, number of transfusions, and complications related to peritoneal dialysis. There were two episodes of peritonitis during the TVPD period and none during the IPD period. Our data indicate that TVPD and IPD are equally effective when applied over similar durations and with similar volumes of dialysis solutions in each session. The improved results with TVPD that others have reported probably can be explained by the use of higher volumes of dialysate.

Effects of gastric fundectomy and antrectomy on the exocrine pancreas in the hamster

The effect of gastric fundectomy and antrectomy on growth of the exocrine pancreas was studied in hamsters over 5 and 25 d. Sham-operated animals served as controls. After 5 d, basal plasma gastrin concentrations were significantly increased in fundectomized animals (80.3 +/- 20.6 pmol/L) and significantly decreased in antrectomized animals (11.6 +/- 1.1 pmol/L) as compared with the controls (20.0 +/- 1.7 pmol/L). Similar differences were present among the 25-d groups, whereas basal plasma cholecystokinin (CCK) concentrations did not differ significantly between any groups at any time. At 5 d after fundectomy, there was a significant increase in pancreatic tissue [3H]-thymidine uptake and total DNA content, both of which were reduced 5 d after antrectomy. Autoradiography showed significantly increased [3H]-thymidine labeling index of acinar, intralobular duct, and centroacinar cells of the pancreas at 5 d after fundectomy. The increased intralobular duct cell labeling index persisted 25 d after fundectomy. Labeling indexes after antrectomy did not differ significantly from those in the controls, although antrectomized animals had the lowest values in all three cell compartments at 25 d. At 25 d, pancreatic wet wt and total DNA and protein content were significantly increased after fundectomy and significantly reduced after antrectomy. These findings indicate that fundectomy in the hamster induces pancreatic exocrine tissue hyperplasia and hypertrophy, whereas antrectomy leads to retardation of pancreatic growth.

Endogenous hypercholecystokininemia model in the hamster: trophic effect on the exocrine pancreas

Using Syrian golden hamsters, we studied the effect of pancreaticobiliary diversion (PBD) on plasma cholecystokinin (CCK) and exocrine pancreatic tissue over 5, 10, and 24 days. As compared with sham-operated controls, PBD-operated animals had increased plasma CCK concentrations by 228, 318, and 207% at 5, 10, and 24 days, respectively. Correspondingly, pancreatic wet weight increased by 24, 61, and 87%; total pancreatic protein by 6, 57, and 73%; and total pancreatic DNA by 35, 52, and 98%, respectively. At 5 days, but not at 10 and 24 days, there was a significant increase in the pancreatic tissue DNA concentration (p less than 0.01) and [3]H-thymidine incorporation into DNA (p less than 0.02). Autoradiography showed increased [3]H-thymidine labeling index in acinar cells at 5 and 10 days after PBD (p less than 0.01 and p less than 0.005). Although not significant, ductal cell labeling index was also increased at 5 and 10 days. These findings provide evidence that, as in the rat, PBD in the hamster induces hypercholecystokininemia with ensuing pancreatic hyperplasia and hypertrophy. The hamster model may be useful for studies on the effect of endogenous CCK on pancreatic ductal cell carcinogenesis and diseases of the gallbladder, neither of which can be studied in the rat.

Effect of pancreaticobiliary diversion on liver regeneration

To ascertain whether the increase in cholecystokinin (CCK) level associated with pancreaticobiliary diversion has a cytoproliferative effect on the liver similar to that on the pancreas, we studied three groups of rats: group I (n = 19) had a pancreaticobiliary diversion and 4 weeks later a 70% liver resection, group II (n = 13) had a liver resection only, and group III (n = 6) underwent a sham liver operation. Tissue samples were taken from the liver and pancreas 48 h after the liver operation. Liver regeneration was evaluated on the basis of continuous incorporation of tritiated thymidine into hepatocytes, liver weight, and DNA content. For confirmation of the increase in CCK levels the effects on the pancreas was studied by measuring wet weight, total protein, and total DNA content. The results showed trophic effects on the pancreas, as expected, but no effects whatsoever on liver regeneration. CCK does not seem to have any role in the regulation of liver regeneration.

Effects of gastric fundectomy and antrectomy on the colonic mucosa in the hamster

The effects of gastric fundectomy and antrectomy on the colonic mucosa were studied in hamsters over 5 and 25 days. Sham-operated animals served as controls. Basal plasma gastrin concentrations were significantly increased after fundectomy and significantly decreased after antrectomy. Five days after fundectomy, there was a significant increase in scintigraphically determined colonic tissue [3H]-thymidine uptake and [3H]-thymidine labeling index of goblet cells, both of which were reduced 5 days after antrectomy. After fundectomy, the labeling index was maximal in differentiating-proliferative cells in the midportion of the colonic crypts, whereas the labeling index of the immature proliferative cells at the base of the crypts did not differ from that in the controls. On day 25, the crypt size and the number and percentage of goblet cells in the crypts were significantly increased in fundectomized animals. The number and percentage of goblet cells in antrectomized animals were significantly reduced on day 25. It is concluded that fundectomy in the hamster induces colonic mucosal hyperplasia with goblet cell proliferation, whereas antrectomy leads to retardation of colonic goblet cell proliferation.

Gastric fundic epithelial proliferation after pancreaticobiliary diversion. Studies with quantitative histological analysis and autoradiography in the hamster

The effect of pancreaticobiliary diversion (PBD) with hypercholecystokininemia on the gastric fundic mucosa was studied in the Syrian golden hamster over 5 and 24 days. Sham-operated animals served as controls. Basal plasma gastrin concentrations were significantly decreased on days 5 and 24. Five days after PBD, there was a significant increase in the scintigraphically measured [3H]-thymidine incorporation into fundic tissue. Correspondingly, there was a significant increase in the number of cells with [3H]-thymidine-labeled DNA in the proliferative zone of the fundic mucosa. The total number of cells in the gastric pits, the number of cells in the proliferative zone and the proliferation index were also significantly increased 5 days after PBD. Although the mean values of all variables were higher after PBD than in the control group on day 24, these increases were not significant. It is concluded that PBD at least transiently stimulates gastric fundic epithelial proliferation in the hamster. Whether this is an effect of hypercholecystokininemia remains to be definitely proven in further studies.

Proliferative response of different exocrine pancreatic cells after surgical pancreaticobiliary diversion in the rat

Pancreaticobiliary diversion (PBD) is known to induce chronic, endogenous hypercholecystokininemia causing pancreatic growth in rats. In the present study the proliferative response of the different exocrine pancreatic cells was studied by administration of 3H-thymidine, 1 mCi/kg, given 1 h before the rats were killed and 5, 10, 20, and 40 days after PBD. DNA and 3H-thymidine uptake, both expressed per 1 mg of pancreatic tissue, were significantly increased on day 5. The nuclear labeling index was increased fivefold in both the acinar and ductal cell group. In the centroacinar cell group the labeling index was increased on day 10. In conclusion, we found that the proliferative activity after PBD occurred during the first 10 days and that the ductal cells were forced into proliferation to the same extent as the acinar ones. These findings are of interest for future studies of hormonal influences on the development of pancreatic carcinoma.

Disseminated dermal dendrocytomas. A new cutaneous fibrohistiocytic proliferative disorder?

A 77-year-old white woman presented with 1 1/2-year history of progressively enlarging cutaneous papules, nodules, and plaques, some of which had spontaneously regressed. Her past medical history included untreated chronic lymphocytic leukemia for 10 years' duration. Multiple skin biopsy specimens revealed a diffuse superficial and deep dermal spindle-cell infiltrate accompanied by occasional foamy round cells and multinucleated giant cells. The spindle-shaped cells were focally arranged in a storiform pattern with prominent fibrous stroma. The spindle-shaped cells stained positively for numerous macrophage markers including CD45, factor XIIIa, Leu M5, HLA-DR, CD4, and Leu M3, consistent with dermal dendrocytes. They were also positive for nonspecific esterase and acid phosphatase, which is typical of tissue macrophages. The spindle-shaped cells were negative for CD-1, S-100, and ATPase activity, thus excluding a Langerhans cell immunophenotype. Combining the clinical features, light microscopy, immunohistochemistry, and enzymatic analysis, this patient appears to represent a novel cutaneous fibrohistiocytic proliferative disorder that features large numbers of dermal dendrocytes.

A splint for controlled active motion after flexor tendon repair. Design, mechanical testing, and preliminary clinical results

A splint for controlled active motion after flexor tendon repair is described. It incorporates a single core-coated elastic band passing around a palmar pulley and attached proximally to a spring wire. Its mechanical properties were tested against six other systems. The tension in various systems all rose near full extension. However, the palmar pulley, the spring wire, and the elastic band each could lower the tension significantly. When the bending moments at the interphalangeal joints were measured, all systems produced a peak during the latter part of extension. With the palmar pulley, spring wire, and elastic band, the rise was minimal and in fact, the bending moments diminished near full extension. Initial results in 28 flexor tendon repairs using this splint showed less flexion contracture when compared with 78 flexor tendon repairs using a standard rubber band anchored at the wrist.

Absorption and disposition kinetics of chlorothiazide in protein-calorie malnutrition

The influence of dietary protein deficiency on the absorption and disposition kinetics of chlorothiazide was investigated in male Sprague-Dawley rats fed for 4 weeks on a 23 per cent (control) or a 5 per cent (low) protein diet ad libitum. Chlorothiazide in plasma and urine was determined by a sensitive and specific HPLC assay. Following an intravenous dose of 10 mg kg-1 chlorothiazide, there was a significant decrease in the total plasma clearance (Cl) per kg of body weight from 1.80 +/- 0.15 to 1.29 +/- 0.15 l h-1 kg-1 and apparent steady-state volume of distribution from 0.65 +/- 0.13 to 0.38 +/- 0.07 l kg-1 in the protein-deficient rats. However, no significant difference was found in the two groups of animals with respect to mean residence time (MRT) and free fraction of drug in plasma. The mean harmonic half-life was increased from 72 to 91 min in the protein-deficient rats. The urinary recovery of unchanged chlorothiazide in 48 h was essentially complete in both groups of animals. The absorption of chlorothiazide, as assessed by the mean urinary recovery of unchanged drug after oral administration, was 66 per cent and 68 per cent in normal and protein-deficient rats, respectively.

Lactase deficiency in Singapore-born and Canadian-born Chinese

Seventy-three of 77 adult Singapore-born Chinese (95%) and 48 of 49 Canadian-born adult Chinese (98%) were demonstrated to be lactase deficient using the lactose breath hydrogen test. The similar prevalence of lactase deficiency in the Singapore- and the Canadian-born Chinese despite a larger estimated amount of daily milk ingestion in the Canadian-born Chinese (430 ml vs 157 ml) supports the concept that lactase deficiency, which is transmitted genetically, does not have an adaptable component related to the quantity of lactose ingested. When the lactose breath hydrogen test performed with a dose of 0.5 g/kg of lactose was compared with the test using a standard dose of 50 g of lactose, there was very little loss of sensitivity. In spite of the presence of lactase deficiency, only 32% of the Singapore subjects and 23% of the Canadian subjects had gastrointestinal symptoms when milk was ingested in the daily diet. Peak breath H2 was higher in females than males, but the difference was more significant in the Canadian cohort.

Heterotransplantation of human prostatic tissue

Pieces of human prostatic tissue (approximately 1 mm3) were encapsulated in XM-50 Amicon hollow fibers and either implanted into the testis of an adult male rat or placed in culture. The protein synthetic capacity of such tissue pieces removed 1-42 days later was monitored by TCA precipitation, SDS-PAGE, and autoradiography. The results showed that tissue pieces retained their functional protein synthetic elements after this procedure. A newly developed solid-phase enzyme immunoassay for human prostatic antigen (PA), described in this report, was used to monitor PA levels in the serum of the recipient host or culture media. In some instances PA was detected 1-2 weeks postimplantation, a result that implies maintenance of functional secretory elements in vivo. Finally, morphology of tissue pieces 1-2 weeks postimplantation sometimes showed the presence of ductal epithelia and stromal elements in distribution patterns typical of those seen in fresh biopsy samples. We conclude that the function and structure of prostatic tissue implanted intrastesticularly compares favorably with that maintained in conventional explant culture. As such, the hollow fiber method offers promise for a new way of monitoring hormonal and/or chemotherapy testing of human prostatic tissue.