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We present a multi-user W-CDMA baseband channel unit processor for cellular base station applications. The ASIC is compliant with the 3GPP/UMTS standard and exceeds 3GPP minimum requirements for high-speed data by 2.2-6.2 dB. It supports up to eight users simultaneously, with a mix of voice and data services and a maximum uplink data rate of 384 kb/s and maximum downlink data rate of 2 Mb/s. The ASIC implements preamble detection, searching, demodulation RAKE-finger processing, channel coding/decoding for voice and data services, and transmission functions. It is coupled to a DSP to form a complete channel element for eight users.

It has been shown recently that longterm but not short term heavy drinking of alcohol frequently results in increased serum activities of pancreatic enzymes suggesting subclinical pancreatic injury. Serum pancreatitis associated protein (PAP) is a novel protein, whose synthesis in the acinar cells and release into serum is specifically induced by acute pancreatic damage. This study was performed to further characterise the alcohol induced subclinical pancreatic injury by using serum PAP measurements. Three groups were studied: (1) control group (n = 25), (2) short term drinking group (n = 20), who consumed 2.0 g of ethanol per kg body weight during four hours, and (3) longterm drinking group (n = 32), who were admitted to withdrawal clinic after a median 30 months heavy drinking period. Serum PAP concentration was low in the control group (8 (5 to 12) micrograms/l, geometric mean (95% confidence intervals)). In the short term drinking group serum PAP was in the range of the control group values during 56 hours after drinking. Longterm drinking induced at least a 10-fold increase in serum PAP, the highest concentrations being seen on day 2 after drinking had ended (106 (61 to 184) micrograms/l). The patients did not develop abdominal symptoms, increased blood white cell count, or increased serum C reactive protein concentration. These results further support the suggestion that heavy longterm drinking often induces subclinical pancreatic damage, but not clinical pancreatitis.

Large scale sequencing of cDNAs from a tissue-specific library provides information on the functional phenotype of that tissue and the clones constitute a reservoir of biological markers. For these reasons, we have randomly sequenced 2166 clones of a cDNA library constructed with human colorectal cancer mRNAs. Database searches indicated that 1014 of the cDNAs represented known human genes or human homologs of other genes, 142 sequences corresponded to known ESTs, 119 sequences corresponded to 28S rRNA, repetitive sequences or poly(A) stretches only, and 891 corresponded to unknown transcripts representing the products of 740 new genes. Preliminary studies demonstrated that expression of some of them was altered in cancer. That cDNA collection is therefore a source of potential markers of colorectal cancer.

Summary Pancreatic gene expression was analyzed in the rat during tauro-cholate-induced pancreatitis, with emphasis on the postacute phase where regeneration occurs. Increased expression of cellular oncogenes c-myc and H-ras followed a pattern typical of tissular regeneration. The c-myc protein was immunolocalized to acinar cells, in which amylase expression was concomitantly decreased. Such modifications in the program of gene expression and the presence of numerous mitotic figures confirmed participation of acinar cells in regeneration. There was, on the contrary, no evidence of duct cell proliferation and pancreatitis did not influence the expression of two mRNAs encoding ductal proteins. Expression of villin, which is a marker of the embryonic pancreas, increased by five times during pancreatic regeneration. The protein was localized to the tubular complexes, suggesting that cells forming those structures had returned to a protodifferentiated stage in which they should have recovered pluripotency. They might therefore supply the pancreas with any cell type needed to reconstitute functional parenchyma.

A panel of kinases whose inhibition increased apoptosis of pancreatic adenocarcinoma cells in vitro was recently established. The aim of this work was to observe in a mouse xenograft model whether inhibition of these kinases would alter pancreatic tumor growth. Rate of apoptosis, caspase-3 activity and cell viability were assessed in two pancreatic cancer cell lines, MiaPaCa2 and BxPC3, after inhibiting selected kinases by transfection of specific siRNAs. For in vivo experiments, MiaPaCa2 cells were injected into the pancreas of nude mice, where they formed tumors. Inhibition of kinases was obtained by repeated intraperitoneal (i.p.) injections of modified O-Methyl (OMe) siRNAs specific for the selected kinases. Tumor volumes were assessed after 21 days. Among selected kinases, PAK7, MAP3K7 and CK2alpha were those whose inhibition increased apoptosis the most in vitro. Simultaneous inhibition of two of them increased apoptosis up to five times. Moreover, inhibiting these kinases had little effect on 10 non-pancreatic cell lines, suggesting pancreatic specificity. In vivo, OMe-siRNAs induced significant but incomplete inhibition of kinase expression (45-75%). Nevertheless, such inhibition resulted in a twofold increase in caspase-3 activity in tumors and a strong reduction in tumor volume (about 75%). In vivo inhibition by OMe-siRNAs of three survival kinases apparently specific for pancreatic cancer cells, PAK7, MAP3K7 and CK2alpha, decreases significantly the growth of xenografted MiaPaCa2 cells. This strategy is therefore of potential clinical interest.

We present a multi-user W-CDMA baseband channel unit processor ASIC for cellular base station applications. The ASIC is compliant with the 3GPP/UMTS standard and exceeds 3GPP minimum requirements for high-speed data by 2.1 to 6.35 dB. It supports up to 8 users simultaneously, with a mix of voice and data services and a maximum uplink data rate of 384 kbps. The ASIC implements preamble detection, searching, RAKE-finger demodulation, channel coding/decoding for voice and data services, and transmission functions. It is coupled to a DSP to form a complete channel element for 8 users. The ASIC has 1.88 M gates plus 2.7 Mbits of SRAM in a 0.16 /spl mu/m CMOS process at 61.44 MHz.

TP53INP1, formerly called either TEAP (thymus-expressed acidic protein) or SIP (stress-induced protein), was identified by microarray technology in mouse. It is a novel gene plausibly involved in the function of thymus (Carrier et al., 1999) and is induced by stress during the acute phase of pancreatitis (Tomasini et al., 2001). The human TP53INP1 counterpart (also called p53DINP1: p53-dependent damage-inducible nuclear protein 1, Okamura et al., 2001) and SIP (Tomasini et al., in press) is a proapoptotic gene induced through TP53 activation. This gene is a stress-induced gene with potential antitumoral properties. We report here the localization of TP53INP1 gene to human chromosome 8q22, in a region that shows conserved synteny with region A1–A2 of the murine chromosome 4 where the mouse gene was mapped (Carrier et al., 2000).

We have used a quantitative fluorescent cDNA microarray hybridization approach to identify pancreatic genes induced by the cellular stress promoted by acute pancreatitis in the mouse. We report the cloning and characterization of one of them that encodes the stress-induced proteins (SIP). The mouse SIP gene is organized into five exons and expands over approximately 20 kilobase pairs. Exon 4 (38 base pairs) is alternatively spliced to generate two transcripts. Northern blot and in situ hybridization showed that both SIP mRNAs are rapidly and strongly induced in acinar cells of the pancreas with acute pancreatitis. They are also constitutively expressed in several other tissues, although with different ratios. They encode proteins of 18 and 27 kDa (SIP(18) and SIP(27)). SIP(27) is identical to the thymus-expressed acidic protein (TEAP) protein, formerly described as a thymus-specific protein. Expression of the SIP(18) and SIP(27)/EGFP or V5 fusion proteins showed that both are nuclear factors. We monitored SIP expression in NIH3T3 cells submitted to various stress agents. UV stress, base damaging, mutagenic stress, ethanol, heat shock, and oxidative stress induced the concomitant expression of SIP(18) and SIP(27) mRNAs. Finally, transient transfection of SIP(18) and SIP(27) expression plasmids induced death by apoptosis in COS7 cells as measured by terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling staining. In conclusion, the SIP gene is an important element of cellular stress response. It is expressed in many tissues and induced by a variety of stress agents affecting many cellular pathways. SIP generates, by alternative splicing, two nuclear proteins that can promote cell death by apoptosis.

We report that exposure of mouse embryonic fibroblasts to transforming growth factor beta-1 (TGFbeta-1) (5 ng/ml) results in a strong activation of p8 mRNA expression that precedes the induction of cell growth. Involvement of the p8 promoter in the regulation was demonstrated by using a p8-chloramphenicol acetyltransferase construct. We therefore speculated that p8 might be a mediator of TGFbeta-1 in these cells. The incorporation of [(3)H]thymidine on treatment with TGFbeta-1 was indeed significantly higher in p8(+/+) fibroblasts than in p8(-/-) fibroblasts. Smad transcriptional activity was used as marker of the TGFbeta-1 signalling pathway, to probe the lower p8(-/-) response to TGFbeta-1. Two Smad-binding elements (SBEs)-luciferase constructs were transfected into p8(-/-) and p8(+/+) embryonic fibroblasts before treatment with TGFbeta-1. A lower level of Smad transactivation was observed in p8(-/-) embryonic fibroblasts, under basal conditions and after stimulation with TGFbeta-1. To test whether Smad underexpression in p8(-/-) cells was actually due to p8 depletion, p8(-/-) embryonic fibroblasts were transfected with a human p8 expression plasmid together with an SBE-luciferase construct. The expression of p8 restored Smad transactivation in unstimulated and TGFbeta-1-treated cells to the level found in p8(+/+) cells. We concluded that TGFbeta-1 activates p8 expression, which in turn enhances the Smad-transactivating function responsible for TGFbeta-1 activity.

The increasing evidence of the benefits of neonatal screening for cystic fibrosis (CF) indicates that this procedure could soon be implemented throughout France. The screening strategy currently used involves the detection of infants with elevated levels of immunoreactive trypsinogen (IRT) (approximately 1% of the population), followed by the detection of CFTR gene mutations. However, genetic analysis has certain drawbacks, the most important of which being the management of heterozygotes, and in France the requirement by law of previous informed consent. In cases of CF, pancreatic alterations are already present in utero. A previous study has demonstrated the value of pancreatitis-associated protein (PAP) as a screening test for CF, and has indicated that a feasible two-stage strategy could involve the following: 1) selection of infants with elevated PAP levels; 2) in this group of infants, subsequent detection of those with elevated IRT levels for direct CF diagnosis by the sweat test thereby avoiding the use of genetic analysis. The study aim was to evaluate this strategy in a large number of neonates.The aforementioned strategy was evaluated in a prospective study involving 47,213 infants in the Provence region of France. In infants with a PAP7.5 ng/mL (1.28%), 176 had an elevated IRT level700 ng/mL (0.37%). In this limited population sample (0.37% of the total), the sweat test diagnosed five cases of CF. A sixth case involving the monozygous twin of an infant with diagnosed CF remained undetected, probably because of a registration error. Genetic analysis confirmed the diagnosis, and also detected another case in an infant with two CFTR mutations but with a normal phenotype at 20 months of age. As the observed incidence was similar to that which had previously been reported, and as no further case was subsequently detected two years after the end of the study, this indicated that the sensitivity of this screening strategy was satisfactory. Its specificity makes the direct diagnosis of CF cases by the sweat test feasible, without further selection by genetic analysis.The PAP/IRT technique for CF detection seems to be suitable for mass screening, without the drawbacks of genetic testing.

Peritoneal colonization is a crucial event in the pathogenesis of peritonitis and its local complications. Adherence to the serosal mesothelium is mediated in a number of microorganisms derived from the digestive tract (especially E. coli) by type-1 fimbriae which have an oligosaccharide specificity.To evaluate the effect of repeated peritoneal washes with saline solution and oligosaccharides on E. coli peritoneal adherence in a rat peritonitis model.Sixty rats were randomized in 3 groups of 20. E. coli was inoculated at a constant concentration of 10(8)/mL per 100 g of weight. Then, peritoneal washes were achieved daily during three consecutive days (D1, D2, D3), with saline solution in Group I (control group), Methyl alpha-D-Mannoside (MADM) in Group II, and p-Nitro-phenyl alpha-D-Mannoside (pNADM) in Group III. Peritoneal samples were obtained before and after lavage at D1, D2, and D3. Microbial recovery was expressed as cfu/mg of tissue, and converted into a percentage of the initial value. A 10% threshold defined efficiency of the wash (inhibition of adherence for 90% of bacteries).Compared with data from Group I, E. coli peritoneal adherence was significantly lower after washes in Group III (D1: p = 0.03; D2: p = 0.009; D3: p = 0.003). Repeated washes were more efficient in Group III than in Group II (D1: p = 0.1; D2: p = 0.5; D3: p = 0.001).These results suggest that the addition of oligosaccharides, especially of pNADM, reduces the peritoneal adherence of E. coli when a peritoneal wash is performed for peritonitis.

Lithostathine and the pancreatitis-associated protein (PAP) belong to the same family of proteins. Several research groups have contributed independently to the description of these proteins, starting from different tissues and different species including human, rat, mouse, dog and cow. Therefore, several names have appeared in the literature for each protein. Identities were discovered later, when cDNA sequences had been obtained and submitted to data banks for comparison. As a result, there is presently no consensus on the nomenclature of the family. Before entering into a description of structural and functional properties of the proteins, the duplications will be recapitulated through a brief historical perspective.

Expression of the pancreatitis-associated protein I (PAP I), an exocrine pancreatic protein, increases rapidly and strongly in acinar cells during the acute phase of pancreatitis. This is reminiscent of the response to stress of acute phase proteins. We have previously demonstrated that serum factors from rats with acute pancreatitis, but not from healthy rats, could induce endogenous PAP I gene expression in the acinar cell line AR-42J (Dusetti, N., Mallo, G., Dagorn, J.-C., Iovanna, J. L. (1994) Biochem. Biophys. Res. Commun. 204, 238-243). In the present work, we have evaluated the influence of several mediators of inflammation on rat PAP I gene transcription in these cells. Tumor necrosis factor alpha induced an increase in PAP I mRNA expression, and interferon gamma caused an even greater increase in PAP I mRNA level. These stimulations were antagonized by dexamethasone. Interleukin (IL)-1, IL-6, or dexamethasone alone were ineffective. Combinations of IL-1 with IL-6 or dexamethasone were also ineffective. IL-6 and dexamethasone together induced a marked stimulation of PAP I gene transcription, and this effect was slightly attenuated by IL-1. To analyze the cis-regulatory elements responsible for the induction of transcription, we fused a 1.2-kilobase segment of the rat PAP I promoter to the chloramphenicol acetyltransferase (CAT) gene as reporter. The resultant chimeric DNA was transfected into AR-42J cells. Addition of IL-6 or dexamethasone was ineffective, whereas their mixture increased the CAT activity 12 times. Progressive deletions of the PAP I promoter were then fused to the CAT gene, and the constructs were transfected to AR-42J cells. A 12-fold increase in CAT activity was seen upon IL-6/dexamethasone treatment with constructs containing more than 274 base pairs upstream from the cap site. In that region, two sequences are similar to the canonical IL-6 response element. Site-directed mutagenesis of these regions strongly decreased induction, showing that they were functional. PAP I should therefore be classified among acute phase proteins of class 2, whose expression is increased by IL-6 acting in combination with glucocorticoids.

Pancreatitis-associated protein (PAP) is a lectin-related protein barely detectable in normal pancreas but overexpressed by this tissue during the acute phase of the pancreatitis. We describe in this report that PAP is constitutively expressed in the human intestinal tract. Northern blot analysis with pancreatic cDNA as probe shows the presence of a transcript in the jejunum that has the same electrophoretic mobility as the pancreatic mRNA. No signal was detected in colon, however. In addition, immunoblotting assays, utilizing specific rabbit immunosera prepared against PAP, revealed the presence of a protein of 16,000 Da (as in pancreatic juice) in the homogenate of jejunum, but not of the colon. When the same antibodies were used for tissule localization of the protein, positive immunoreactivity was observed on Paneth cells and in some goblet cells located in jejunum at the bottom of the crypts. No staining was observed in colon.

Neonatal screening of cystic fibrosis (CF) is presently based on immunoreactive trypsin (IRT) assay in blood spots, whose low specificity is a matter of concern. Because the pancreatitis-associated protein (PAP) proved to be a better serum marker of pancreatic alteration than exocrine enzymes, it might be an interesting alternative for CF screening. We report here a preliminary evaluation of the PAP test, conducted in retrospect on blood spots from groups of neonates already screened for CF with the IRT. Neonates with elevated IRT were submitted to subsequent analysis of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene. Neonates with normal IRT (n = 990) or high IRT but normal genotype (n = 28) had normal PAP. Elevated PAP was observed in all CF neonates (n = 11). False-positives for the PAP test were found only among neonates with high IRT and heterozygotes for a mutation in the CFTR gene (6 out of 17 cases). That group represents less than 0.2% of newborns. These results therefore suggest that PAP discriminates CF neonates with a significantly better specificity than IRT.

The pancreatitis-associated protein (PAP) is undetectable in normal pancreatic secretion and overexpressed in the acute phase of pancreatitis. We investigated whether serum PAP could be an indicator of the course of acute pancreatitis.Serum PAP was retrospectively monitored in 98 patients with acute pancreatitis during their stay in the hospital. Patients were classified according to the severity of their disease as group I (or = 1 complication), group II (or = 2 complications), or group III (lethal pancreatitis).At admission, 34% of patients, all from group I, had normal PAP values (10 micrograms/L). None of them developed complications. They had a significantly shorter stay in the hospital than patients with elevated PAP (6.2 days vs. 14.9 days). In all patients, serum PAP increased after admission to a maximum, which correlated significantly to the severity of the disease. Average peak values were 22.2 micrograms/L and 240.0 micrograms/L in group I patients with normal or high PAP at admission, 963.0 micrograms/L and 1436.0 micrograms/L in groups II and III. Serum PAP decreased steadily during recovery.Monitoring serum PAP in patients with acute pancreatitis would provide (1) at admission, selection of most patients who will not develop complications; (2) a dynamic assessment of severity; and (3) anticipation of the patient's recovery.

In different tissues alteration of protein synthesis has been observed during acute stress. In this review we characterise the modulation of pancreatic protein synthesis during inflammation. A sustained decrease of mRNA levels of secretory enzymes is accompanied by noncoordinated alterations of protein synthesis during the acute phase and the recovery from pancreatitis. For that regulation both translational and transcriptional alterations are of importance. The most prominent finding was the expression of pancreatitis-associated proteins (PAP) in humans or rats, which are absent in the normal gland but synthesised during acute pancreatitis. PAPs are pancreatic secretory proteins, their mRNA were cloned and sequenced and the sequence of encoded preproteins of 175 amino acids were deduced. The PAP expression increased as a function of the severity of pancreatitis. It can be assayed in serum and may be used as a marker of the disease. Due to its affinity to bacterial surfaces the PAP molecule could act as an endogenous antibiotic factor that prevents the bacterial infection of the inflamed pancreas.

The control of the formation of crystals in biological fluids is one of the most exciting field of research involving both organic and biochemical areas. Many organisms have evolved mechanisms which minimize or avoid the effects of nucleation and crystal growth formation. One of the most important mechanism is the interaction of specific proteins, called inhibitors, with crystals which alters their habits and leads to their elimination. This article, focused on saliva, pancreatic juice and bile, reviews our present knowledge on the structure-function relationships existing between these proteins and their ability to inhibit the growth of different calcium salt crystals.

Rat pancreatitis-associated protein (PAP) mRNA is barely detectable in normal pancreas and overexpressed during acute pancreatitis (Iovanna, J., Orelle, B., Keim, V., and Dagorn J.-C. (1991) J. Biol. Chem. 266, 24664-24669). RNA amplification by reverse-transcriptase-coupled polymerase chain reaction showed that PAP mRNA was constitutively expressed in duodenum, jejunum, and ileum, at similar levels as in pancreas during the acute phase of pancreatitis. A weak expression was also detected in several other tissues. The rat PAP gene was isolated from a genomic library and characterized over 3.2 kilobases of gene sequence and 1.2 kilobases of 5'-flanking sequence. The 5' end of the coding sequence was determined by primer extension of the PAP transcript. Several potential regulatory elements were identified in the promoter region, including a pancreas-specific consensus sequence, two Pan1 (pancreas-specific) transcription activators, two IL-6 response elements, and one glucocorticoid response element. The PAP coding sequence spanned over six exons. The first three exons encoded the 5'-untranslated region of the mRNA, the signal peptide, and 39 amino acids of the NH2-terminal end of the mature protein, respectively. The other three exons encoded a domain of the protein with significant homology to the carbohydrate-recognition domain of animal lectins. Sequence comparison of the PAP gene with 13 carbohydrate-recognition domain-containing genes revealed that they derived from the same ancestor gene. Position of introns within the carbohydrate-recognition domain were different, however, suggesting that PAP belongs to a new group of lectins. These results support the hypothesis that genes encoding PAP and other lectins evolved from a common ancestor gene by intron gain.

The purpose of the present study was to examine the weight, DNA content, and enzyme mRNA levels in the pancreas in response to endogenous hypercholecystokininemia produced by pancreaticobiliary diversion (PBD) in starved rats. The results showed that PBD, which is known to increase the circulating cholecystokinin (CCK) concentration, prevented the reduction in the weight and DNA content of the pancreas after 3 days of starving, and that PBD increased the mRNA levels of amylase, chymotrypsinogen B, and procarboxypeptidase A in the pancreas of starved rats. The findings support the view that endogenous CCK plays an important role in maintaining the weight of the normal pancreas of starved rats and that it stimulates the transcription of genes coding for pancreatic exocrine enzymes.

Lithostathine is a protein of pancreatic secretion inhibiting calcium carbonate crystal growth. Antibodies to lithostathine were used to identify a related protein in urine and kidney stones. Western blot analysis of proteins extracted from concentrated normal urine or kidney stones demonstrated the presence of a protein with an apparent molecular weight of 23 kDa. The same antibodies were used in immunolocalization experiments on fresh human nephrectomy specimens cryosections. A positive signal was observed in the cells of proximal tubules and thick ascending limbs of Henle's loop. Protein extracts of renal stones inhibited calcium carbonate crystal growth. Because of its structural and functional similarities with pancreatic lithostathine, it was called renal lithostathine.

Pancreatic juice is naturally supersatured in calcium and bicarbonate ions. A mechanism controlling CaCO3 crystal formation and growth is therefore necessary to prevent duct clogging. Lithostathine, a glycoprotein synthesized by acinar cells and secreted in pancreatic juice, could be involved in such a control. Lithostathine significantly delayed crystal nucleation and inhibited growth of CaCO3 crystals from supersatured solutions. Lithostathine adsorbed to sites specifically inhibiting crystal growth with a dissociation constant Kd = 0.9 x 10(-6) mol/L. The glycosylated N-terminal undecapeptide generated by limited trypsin hydrolysis of lithostathine, inhibited CaCO3 crystal growth with a Kd = 3.4 x 10(-6) mol/L similar to that of lithostathine. On the contrary, the carboxy-terminal polypeptide (lithostathine H) was inactive. The N-terminal undecapeptide of lithostathine is therefore essential to the inhibitory activity of the protein on CaCO3 crystal growth.

Rat pancreatitis-associated protein (PAP) is an additional protein appearing in pancreatic juice after induction of prancreatic inflammation. Its messenger RNA was cloned and sequenced from pancreas. The deduced amino acid sequence revealed that PAP was synthetized as a preprotein with, in its mature form, a predicted molecular weight of 16,630. A search in protein data bases revealed a marked homology with the carbohydrate binding region of animal lectins; no hemagglutination activity could be shown for PAP, but the protein induced extensive bacterial aggregation. In healthy rats, the very low level of PAP expression in pancreas could be increased up to 4-fold by physiological stimuli such as chronic hormonal or cholinergic stimulation of pancreatic secretion and adaptation of rats to a carbohydrate-rich diet. By contrast, induction of acute experimental pancreatitis by retrograde injection of sodium taurocholate resulted in dramatic overexpression. Pancreatic concentration of PAP mRNA increased more than 300 x within 12 h whereas concentrations of mRNAs encoding major secretory proteins such as amylase decreased. PAP overexpression persisted during the 2 days of the acute phase and then returned to the control level during pancreatic recovery. PAP mRNA could not be evidenced in liver, stomach, salivary glands, brain, kidney, or testis. Its pattern of expression during severe pancreatic aggression suggests that it might be a stress protein involved in the control of bacterial proliferation.

We used a cDNA encoding the human pancreatic stone protein (PSP-S), the secretory inhibitor of CaCO3 crystal growth, as a probe for cloning rat PSP-S messenger RNA. Overlapping clones gave a mRNA sequence of 783 nucleotides encoding a preprotein of 165 amino acids including a prepeptide of 21 amino acids. Rat and human PSP-S showed 70% identity, and the mature proteins had the same length. PSP-S mRNA concentration was measured in the pancreas of rats adapted to diets containing 15, 25, or 70% protein. Compared with the 15% protein diet, concentration increased 3 and 12 times with the diets with 25 and 70% protein, respectively, which is 3 times higher than for serine proteases. A complete sequence identity was observed between the rat PSP-S transcript and the reg mRNA described by Terazono et al. (Terazono, K., Yamamoto, H., Takasawa, S., Shiga, K., Yonemura, Y., Tochino, Y., and Okamoto, H. (1988) J. Biol. Chem. 263, 2111-2114), which is expressed in regenerating pancreatic islets but not in mature islets. A specific role of the reg protein in islet regeneration was suggested. We found that PSP-S (reg) mRNA concentration was indeed increased in isolated regenerating islets. Yet, a transient increase was also observed in exocrine tissue during the initial phase of regeneration following pancreatectomy or acute pancreatitis, suggesting increased expression during cell dedifferentiation. It is concluded that, in mature pancreas, expression of the reg/PSP-S gene occurs primarily in acinar cells. The gene product, which encodes a secretory protein inhibiting CaCO3 crystal growth in juice, is unlikely to play a specific role in islet regeneration.

Pancreatic secretion of mammals contains about 20 principal protein species (Rinderknecht 1986). Most of these secretory proteins are directly implicated in the digestive process. Our laboratory has reported the presence in human pancreas of a protein apparently devoid of enzyme activity (Montalto et al. 1986) and named secretory pancreatic stone protein (PSP-S) because of its immunological identity with the pancreatic stone protein, the major component of the protein matrix present in calculi of patients suffering from chronic calcifying pancreatitis (CCP). In human pancreatic juice collected over an appropriate mixture of protease inhibitors, PSP-S comprised four species with apparent M r between 16 and 20 kDa, named PSP-S2 to PSP-S5 (de Caro et al. 1988). However, immunoprecipitation of in vitro translation products of pancreatic RNAs showed that PSP-S was synthesised as a single polypeptide (Giorgi et al. 1985a). Hence, PSP-S is a protein entity with a molecular weight heterogeneity probably due to postranslational processing. An additional PSP- S form (PSP-S1) appears in pancreatic juice upon activation. PSP-S1 with a M r of 15 kDa derives from PSP-S2-5 by trypsin-like cleavage of an Arg-Ile bond in the NH2-terminal part of the protein (Rouimi et al. 1987).

Emulsifying properties of purified pea globulins and of vicilin-legumin mixtures were evaluated through their emulsifying capacity, emulsifying activity index and stability of the resulting emulsions. The results were discussed by reference to the interface adsorption behaviors of these proteins. The influence of the vicilin/legumin ratio on the efficiency of pea isolates as emulsifying agents was also studied. Vi-cilin which has been shown to be more surface active at air/water and dodecane/water interfaces, led also, in both cases, alone or mixed, to better emulsifying properties than legumin. The globulin composition of the isolates did not completely explain their emulsifying behaviors.

The interfacial behaviours of the two main pea globulins (legumin and vicilin) at water/air interfaces were studied in order to improve the general knowledge concerning the physicochemical basis of the foaming and emulsifying properties of these proteins. The surface tension (γ) was monitored by the WILHELMY plate technique till it reaches a constant value. The final concentration c of the proteins injected in the subphase was comprised between 0.3. 10−6 and 80. 10−6 g/ml. The adsorption kinetics γ = f(t) were analyzed using different mathematical relations given in the literature. Different phases can be distinguished, corresponding to the diffusion, penetration and rearrangement of protein molecules at the interface, each phase being characterized by a rate constant and an energy barrier. The rate constants were generally higher in the case of vicilin; in consequence the equilibrium surface pressure π were reached more quickly. The isotherms πe = f(log c) showed that the concentration needed to reach the plateau value of πe, were respectively about 11.7. 10 6 g/ml and 18.5. 10−6 g/ml for vicilin and legumin air/water interface. The plateau value of πe, was about the same for both proteins at air/water interface (24.5 mN/m). For lower concentrations, vicilin gave higher values for ne. The areas per molecule in the adsorbed monolayer were about the same for vicilin (1.05 nm2) and legumin (1.04 nm2) at air/water interface. By studying the surface properties of vicilin/legumin mixtures it was observed that πe increased with increasing relative concentration of vicilin and that inhibiting interactions occured between the two globulins, legumin adsorption being more disturbed by vicilin than the opposite. According to these results, the differences between legumin and vicilin can be related to their molecular characteristics. Pea globulins and especially vicilin appeared to be efficient proteins as surface active agents.

Since nonparallel secretion of enzymes by the exocrine pancreas has been demonstrated with several experimental models, we were interested in verifying a recent claim that enzyme secretion remained strictly proportional (parallel) upon stimulation of the in vivo rabbit pancreas. Pancreatic juice was collected by extraduodenal cannulation of the pancreatic duct, in two different protocols. In the first protocol the administration of pentobarbital induces a mild anesthesia. Under this condition, amylase and chymotrypsin secretion remained parallel after cholecystokinin stimulation. In a second protocol, a deeper and constant anesthesia was attained with Fluothane resulting in a lower basal protein output than in the first protocol. Pancreatic secretion was collected under intravenous secretin perfusion (4.5 clinical units∙kg−1∙h−1). After stabilization and basal collection periods, pancreatic secretion was stimulated with an i.v. bolus injection of either cholecystokinin (2 Ivy dog units/kg), caerulein (0.1 μg/kg), or carbachol (6 μg/kg). Upon stimulation of the pancreas, protein output increased an average of 30-fold and there was a concomitant 20–25% decrease in the ratio of the specific activities of amylase to chymotrypsin which resulted from a greater increase in the specific activity of chymotrypsin in pancreatic juice after stimulation of secretion. Thus, under appropriate conditions, nonparallel secretion of enzymes by the exocrine pancreas can be demonstrated in yet another experimental model. Furthermore, the proportion of amylase and chymotrypsin activities in pancreatic juice are once more shown to be dependent, up to a threshold, upon the rate of protein output by this exocrine gland.

The kinetics of the adaptative changes in the relative rates of synthesis and pancreatic concentrations of amylase, chymotrypsinogen and trypsinogen were studied over 10 days of adaptation to a carbohydrate-rich (G), or a protein-rich (P) diet. During adaptation to the P diet, 60% of the adaptative decrease of the amylase to chymotrypsinogen ratio of incorporation was complete within 24 h of feeding and plateau values were obtained after five days. Adaptation to the G diet was only 20% complete after 24 h and plateau values were obtained later than with the P diet. The evolution of the ratio of concentrations of amylase and chymotrypsinogen followed those of incorporation in the adaptation to both diets. These results support the determinant role of adaptative changes in the rates of synthesis of individual enzymes on the dietary adaptation of enzyme proportions in the pancreas. The differences in the kinetics of adaptation to the two diets suggest that different mechanisms are involved in the adaptative regulation of protein synthesis to a carbohydrate-rich diet or a protein-rich diet.

Dietary adaptation of pancreatic protein synthesis and of pancreatic enzyme concentration, was studied over the first 24 h of exposure to a new diet. Rats were adapted to a carbohydrate-rich (G) or to a protein-rich diet (P) and were switched to the opposite regime after a 15 h fast. The evolution of the relative rate of synthesis of amylase, chymotrypsinogen and trypsinogen and of the pancreatic concentration of amylase and chymotrypsinogen were followed. Fasting caused important modifications in the relative rate of synthesis of the three enzymes in rats adapted to a P diet. Adaptative changes in the relative rate of synthesis of amylase, chymotrypsinogen and trypsinogen were seen within 2 h after the beginning of refeeding. These changes were followed by corresponding adaptative modifications in pancreatic contents 4 h after the beginning of refeeding. After 24 h of refeeding, significant adaptative changes had occurred in both the relative rates of synthesis and in enzyme concentrations. Thus exocrine pancreatic protein synthesis can be modulated as early as 2 h after refeeding and this modulation is followed by adaptative changes in pancreatic enzyme content.

The effect of neurotensin on rat pancreatic secretion was studied in the conscious animal as well as on pancreatic lobules. In vivo neurotensin induced a dose-related inhibition of both water and protein basal secretion. Protein secretion was much more depressed than fluid secretion. Neurotensin did not modify the pancreatic response to exogenous secretin or cholecystokinin-pancreozymin, or to intraduodenal infusion of HCl. On the other hand neurotensin totally inhibited the increase in volume as well as in protein output to an intraduodenal infusion of oleic acid, but did not change the delayed inhibitory effect on protein output. In vitro, neurotensin did not affect basal and cholecystokinin stimulated pancreatic secretion. These results indicate that: 1) neurotensin could interfere with the release of hormones from the gut (cholecystokinin, and possibly VIP), 2) neurotensin did not mimic the delayed protein inhibitory effect observed after administration of oleic acid.

The present study has been undertaken to determine in the rat the influence of exocrine secretory stimulation on pancreatic protein synthesis. This stimulant consisted of a single injection of cholecystokinin–pancreozymin (8 Ivy units/kg) plus secretin (5 clinical units/kg). The rate of [14C]phenylalanine incorporation into total proteins was measured 5, 11, 17, 30, 45 and 60 min later. Incorporation was significantly decreased after 5 min, then significantly increased at 17 min, and finally returned to control values at 45 min. This biphasic evolution was shown not to be caused by variations in the precursor pool specific radioactivity. We concluded that secretory stimulation of the pancreas can induce a decrease in the rate of protein biosynthesis. This decrease is nevertheless a transient phenomenon, since the rate of biosynthesis was increased at 17 min. These results, obtained from a totally in vivo system, confirm previous data obtained from an in vivo – in vitro system.

1. The relative variations of rat pancreatic amylase versus lipase and chymotrypsinogen secretions have been studied in vitro with the help of two different techniques: in situ organ perfusion and incubation of pancreatic lobules. 2. In experiments on the perfused pancreas, with 8 C u.kg-1 hr-1 secretin added to the perfusion fluid, cholecystokinin-pancreozymin (8 ID u.kg-1) or pilocarpine (15 mg kg-1) both resulted in a significant change in the enzyme proportions in the juice. 3. In experiments on pancreatic lobules, the addition to the incubation medium of secretin (10(-7) M), alone or associated with cholecystokinin-pancreozymin (8 x 10(-7) M) or pilocarpine (10(-4) M) did not induce any change in the enzyme proportions in secretion. 4. It was concluded that the non-parallelism between enzyme secretions can occur in the rat upon pancreozyminic or cholinergic stimulation in vitro as well as in vivo (Dagorn, 1978) provided basal protein output is low enough. This is not the case when the tissular integrity of the pancreas is lost, such as in experiments on lobules. 5. This work confirms that pancreatic secretion derives from two intrapancreatic pools of different enzymatic composition, and gives a possible explanation for some discrepancies from the literature on the existence of non-parallel secretion.

The short-term influence of repeated secretory stimulations of the pancreas on pancreatic enzyme content was studied in the rat. The animals received 10 successive injections of either cholecystokinin-pancreozymin (CCK-PZ), secretin, CCK-PZ plus secretin, caerulein or pilocarpine. The pancreatic enzyme content was determined the next morning. CCK-PZ, with or without secretin, caerulein and pilocarpine had a similar influence increasing the chymotrypsinogen concentration in the pancreas twofold, while lipase and amylase concentrations increased by only 50 and 25%, respectively. Fasted and fed animals responded similarly. Secretin, a mostly ductal secretagogue, was without influence on the pancreatic enzyme composition. Thus, the mere stimulation of pancreatic protein secretion seems to result in a rapid change in enzyme composition in the pancreas.

The formation of large aggregates by ionic interactions between acidic glucosaminoglycans and cationic secretory proteins has been proposed as one of the critical steps in the concentration process in the condensing vacuoles of secretory cells. In this paper, this hypothesis was tested by studies on the interactions between bovine chymotrypsinogen A and chondroitin sulfate as a simplified model. Small amounts of chondroitin sulfate were found able to induce chymotrypsinogen precipitation. Like zymogen granules, the resulting aggregates were moderately sensitive to ionic strength and insensitive to osmolality. Moreover, their pH dependence was similar to that of isolated zymogen granules. When sulfated glucosaminoglycans isolated from the zymogen granules of the guinea pig pancreas were used instead of chondroitin sulfate, the same kind of interactions with chymotrypsinogen were obtained. Our data support the hypothesis that the strong ionic interactions between those sulfated glucosaminoglycans and cationic proteins could be responsible for the concentration process.

This work is part of general program of the diagnostic radiation dosage monitoring in the C.H.U. of Brest. The aim of these measurements is to precise the doses delivered to the sensitive organs in infants from one to thirty days of age in the intensive care pediatric Department. We present in this paper the technology used and the results of these controls. We complete this experimental work with a statistical study of the number of radiographies made in the intensive care pediatric Department on 623 children. We insist on the use of leaded protection in the radiodiagnostic practice, as often as it is possible.