Thyroxine control of pancreatic amylase gene expression: modulation of PTF1 binding activity

The role of pancreas specific transcription factor (PTF1) in thyroxine (T4) modulation of amylase gene expression in suckling rats was evaluated. Electrophoretic mobility shift assay (EMSA) was used to determine the PTF1 binding activity by the amount of a synthetic oligonucleotide containing the amylase enhancer sequence bound by nuclear protein extracts. Nuclear protein from rat pancreata showed a developmental increase of PTFI activity correlated with age. To study the action of T4, pups were made hyperthyroid by T4 injection and hypothyroid by feeding propylthiouracil (PTU) to the lactating dams. EMSA of nuclear proteins isolated from these groups showed an increase in PTF1 binding activity in the T4 group and a decrease in the PTU group. Concomitantly, T4 increased, while PTU decreased both amylase enzyme and mRNA concentrations. T4 replacement reversed the effect of PTU on PTF1 binding, amylase enzyme activity and mRNA levels. To examine the age dependence of T4 effects, T4 was injected to pups for 5 days prior to killing at the age of 15, and 25 days. T4 was effective when given at an earlier age (15 days) but not at a later stage (25 days) in increasing amylase activity and amylase mRNA levels. Nuclear proteins isolated from pancreata of these groups showed an increase in PTF1 binding activity in the T4-treated 15-day-olds but not in the 25-day-olds in comparison to their corresponding age matched littermates. These results suggest that PTF1 is an important intermediary in T4 modulation of amylase gene expression during ontogeny of the rat exocrine pancreas.

Comparison of mutation spectra induced by N-ethyl-N-nitrosourea in the hprt gene of Mer+ and Mer- diploid human fibroblasts

N-Ethyl-N-nitrosourea (ENU) forms several major adducts upon reaction with DNA, of which ethylation at the O6 position of guanine and the O4, O2 and N3 positions of thymine have been implicated to be mutagenic lesions. To investigate what specific kinds of ENU-induced mutations were affected by the repair ability of O6-alkylguanine-DNA alkyltransferase (AGT), we examined the mutations in the hypoxanthine (guanine) phosphoribosyltransferase gene (hprt) in 87 independent mutants derived from ENU-treated AGT proficient (Mer+) or deficient (Mer-) diploid human fibroblasts. Of the characterized mutations, 97% were single base substitutions. The major difference in the mutation spectra was that the frequency of G.C to A.T transitions was significantly higher in Mer- mutants (16/38) than in Mer+ mutants (4/33). The results indicate that AGT removes O6-ethylguanine, thus protecting human cells from parts of the cytotoxic and mutagenic effects of ENU. A high frequency of T.A to A.T transversions induced by ENU was observed in both Mer+ (52%) and Mer- (34%) mutants. This type of mutation was less frequently observed (10%) in N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced mutants derived from the same Mer+ cells in our previous report (J. Mol. Biol., 221, 421, 1991). Comparison of alkylating lesions formed by MNNG and ENU indicates that O2-ethylthymine and N3-ethylthymine are potent mutational adducts for T to A transversions. The occurrence of ENU-induced T.A base pair transversions showed a strong strand bias; 35/37 were located on the non-transcribed strand, assuming thymine is the mutagenic lesion. The result suggests a difference in repair capacity of ethylthymine on the two strands. In addition, this type of mutation preferentially occurred at 5'-Pu-T sequences.

Neutrophil adhesion and complement inhibition prolongs survival of cardiac xenografts in discordant species

Hyperacute rejection results in rapid destruction of a discordant cardiac xenograft and is characterized by antibody deposition, complement activation, and platelet aggregation. The importance of neutrophils is unclear. Complement inhibition prolongs discordant cardiac xenograft survival. The purpose of this experiment was to determine the relative roles of complement and neutrophils. Selective inhibition of complement and neutrophil adhesion was used in a guinea pig-to-Lewis rat cardiac heterotopic xenotransplant model. NPC 15669 (N-[9H-(2,7-dimethylfluorenyl-9-methoxy)carbonyl]-L-leucine), a member of a new class of antiinflammatory agents termed leumedins, specifically prevents recruitment of neutrophils at inflammatory foci by inhibiting upregulation of the CD11b/CD18 adhesion molecule. Soluble complement receptor type 1 (sCR1, BRL 55730) is a potent inhibitor of the alternative and classical complement pathways. Group I (n = 13) received saline vehicle i.v. Group II (n = 15) was treated with NPC 15669 (10 mg/kg i.v. bolus) prior to reperfusion. Group III (n = 13) was treated with sCR1 (20 mg/kg i.v. bolus) prior to reperfusion. Group IV (n = 13) received both NPC 15669 and sCR1. Two xenografts were harvested at each interval time point (Groups I and II, 1, 2, 4, and 6 min; and Groups III and IV, 6, 15, 30, and 60 min). The remainder were followed to cessation of graft function. Graft survival was significantly increased in group IV and group III-375 +/- 13.4 min (mean +/- SD) and 112 +/- 29.4, respectively (P < .05), compared with 9.9 +/- 6.3 in group II and 8.7 +/- 4.9 in group I. Extreme interstitial hemorrhage and edema and contraction band injury were present in group I-III animals at end-stage, and neutrophil infiltration in group III. In group IV grafts, there was a decrease in these parameters despite the longer survival time, and at end-stage rejection the cellular infiltrate was primarily mononuclear. This study demonstrates that complement is an important mediator in early xenograft HYP injury. Combined treatment with NPC 15669 and sCR1 results in reduced histologic injury at all time points and longer graft survival than with sCR1 alone. These results suggest that neutrophil and complement activation play synergistic roles in the pathogenesis of xenograft hyperacute rejection. Neutrophil inhibition may prove to be an important component of multimodality therapy for hyperacute rejection, particularly in less-discordant transplants.

Faecal enzymes: in vivo human skin irritation

Digestive enzymes in faeces have been reported to possess skin irritation potential. The present study was designed to investigate the in vivo irritant potentials of faecal concentrations of proteolytic and lipolytic digestive enzymes in bile salt mixtures. In a 21-day cumulative irritation assay, clinical evaluation and noninvasive bioengineering techniques were used. 5 days occlusive exposure to phosphate buffer (pH = 8) caused no visual skin damage but reflectance spectroscopy demonstrated significant vasodilation (p < 0.01) and increases in transepidermal water loss (TEWL) and skin pH were also observed (p < 0.01). These increases were still present at days 12 and 19. Occlusive exposure to physiologic concentrations of faecal enzymes resulted in significant visual and objective scores at day 5, 12, and 19, with increased readings as a function of exposure time (p < 0.01). The enzyme mixture containing lipase caused delayed onset of skin erythema and epidermal barrier disruption compared to elastase and chymotrypsin containing solutions. Prolonged occlusive exposure to digestive enzymes in faecal concentrations caused severe skin erythema and epidermal barrier disruption in a human model, suggesting a possible etiologic role of digestive enzymes in perianal, circumstomal or diaper dermatitis.

Beam-hardening effects of wedges on a spoiled 6 MV beam

The beam-hardening effects of the wedges on a 6-MV spoiled beam has been studied. The beam quality of all the wedged beams was found to be the same as the open beam. The dmax also stayed unchanged for all the wedges at all field sizes. The relative wedge factors were found to reflect the beam-hardening effect, which is a function of the wedge angles, depths, and field sizes. For the 15 degrees and 30 degrees wedges, the relative wedge factor at depths less than 15 cm were found to deviate less than +2% for all fields, while those for the 45 degrees and 60 degrees wedges for the same depth range from +3% to +4%. The surface doses were found to decrease with the wedged fields. For 15 degrees, 30 degrees, and 45 degrees wedges, the decreases were found to be from 0 to -2.0%. For 60 degrees wedges, the largest deviation was found to be -2.5% for a field size of 10 cm x 10 cm at a depth of 2 mm. The wedge factors at dmax were found to depend slightly on the field sizes. The use of an averaged wedge factor for each individual wedge was found to produce less than +/- 1.2% of error for all field sizes.

Continuous succinylcholine infusion and phase II block in short surgical procedures

The study was designed to observe continuous succinylcholine infusion and phase II block in short surgical procedures (duration < 90 min). The characteristics of neuromuscular blockade produced by continuous succinylcholine infusion were observed in 15 adult patients anesthetized with nitrous-oxide-isoflurane (0.7% end tidal concentration) and fentanyl, and were compared with the single-dose technique (n = 13) in recovery time. Ulnar nerve was stimulated supramaximally with repeated train-of-four (interval = 10 sec, frequency = 2 Hz) via surface electrodes at the wrist using an electromyographic monitor (Datex, Relaxograph, Finland). The infusion rate was adjusted to maintain the height of the first twitch (T1) in each train of four at 5-10% of control twitch height. The mean duration of infusion was 50.74 +/- 18.06 minutes. The steady state infusion rate required to maintain 90% to 95% twitch depression was 83.5 +/- 21.4 micrograms/kg/min. Five patients developed phase II block (T4/T1 < 0.5) designated as IB. The other ten did not develop phase II block as IA. Recovery times (T1 = 10.50%, 10-100%) between IA and IB were not statistically significantly different. The recovery time of train-of-four fade (T1 = 10% to T1 = 100% and train of four > 75%) was 5.73 +/- 0.43 minutes. However, recovery times between continuous infusion group and single dose group were significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)

Protein kinase C and CYP1A1 induction in rainbow trout (Oncorhynchus mykiss) hepatocyte culture

1. The role of protein kinase C (PKC) in B-naphthoflavone (BNF) induction of CYP1A1 in rainbow trout hepatocytes was investigated. 2. Primary cultures of rainbow trout hepatocytes treated with BNF for 24 hr showed an increase in microsomal 7-ethyoxyresorufin-O-deethylase (EROD) activity compared to cells treated with vehicle (DMSO) only. 3. Increases in EROD activities were proportional to increased concentrations of BNF from 1 to 10 nM reaching a plateau at higher concentrations (20-100 nM) of BNF. 4. Western blot analysis using specific antibody (LM4b) against CYP1A1 showed that changes in microsomal CYP1A1 protein paralleled that of EROD activity. 5. The induction of EROD activity by BNF required both protein and RNA synthesis since the process was blocked by both cycloheximide and actinomycin D. 6. Pretreatment of hepatocytes with 12-O-tetradecanoyl-phorbol-13-acetate (TPA) led to a dose dependent suppression of BNF-induced EROD activity and CYP1A1 content. TPA alone had no effect on hepatic EROD activity and CYP1A1 protein level. 7. Pretreatment with sn-1,2 didecanoylglycerol, a PKC activator, had no effect on BNF-induced EROD activity in these cells. 8. Pretreatment of cells with staurosporine, a PKC inhibitor, effectively blocked BNF-induced EROD activity. 9. PKC may play a role in the induction of CYP1A1 gene expression in fish liver by BNF.

Protection of the internal mammary artery pedicle with polytetrafluoroethylene membrane

With increasing frequency, reoperative coronary artery bypass surgery is being performed in the setting of a patent internal mammary artery (IMA) graft. Injury to the IMA graft at reoperation can result in ischemic myocardial injury and cardiac arrest. This descriptive laboratory study examined use of a polytetrafluoroethylene (PTFE) membrane wrap to protect the IMA pedicle during sternal reentry. Six pigs (25-30 kg) underwent median sternotomy and takedown of left and right IMAs. Grafts were implanted in the epicardium by a modified Vineberg procedure. In each animal, one IMA was wrapped circumferentially with PTFE, while the contralateral bare IMA served as the control. Redo sternotomy was performed 3 months later. Severe adhesions between chest wall, myocardium, and bare IMA grafts were encountered in six of six animals. PTFE-wrapped IMAs were easily identified by appearance and by palpation. There was no adherence between PTFE membranes and surrounding tissue, nor was there evidence of cellular infiltration, disruption, or contraction of the membrane. Most notably, PTFE membranes could not be cut or injured with the electrocautery, since they are electrical nonconductors. This study demonstrates that PTFE membrane: (1) is relatively inert and incites minimal surrounding tissue reaction; and (2) is impenetrable to electrocautery injury. Further studies are necessary to determine the impact of PTFE membrane on IMA graft patency and wound infection. PTFE membrane may prove clinically useful in protecting patent IMA pedicles during reoperative cardiac surgery.

Development of lipolytic activity in gastric aspirates from premature infants

Neonates, having little or no pancreatic lipase, would have a compromised ability to digest lipids if not for lingual and gastric lipases. To document the postnatal developmental profile of preduodenal lipase activity, 350 premature infants who were at various gestational ages and who had an orogastric tube had their gastric aspirates collected. Two hundred one infants had their gastric aspirates collected within 12 h after delivery. Serial collections were performed in 25 infants at various postnatal ages. Gastric aspirates collected from premature infants had a pH activity profile similar to that of lingual and gastric lipase but different from that of pancreatic lipase, indicating that their origin was from the tongue and/or stomach. Lipolytic activity and pH of these aspirates were quite variable, but no correlation was found between pH and enzyme activity. At birth, lipase activity was lower in the younger infants (< or = 26 weeks, n = 13). It increased to a peak at 30-32 weeks of gestational age and then declined to a lower level at term (> or = 40 weeks, n = 40). Postnatally, a composite plot of the serially collected aspirates also showed a predominant peak at 28-33 weeks of age. Comparison among siblings in twins (n = 12 pairs) and triplets (n = 3) showed great variations in their lipolytic activities, suggesting that the hereditary factor is not a major determinant. Various combinations of antibiotic medications (ampicillin, cefotaxime, gentamicin, and vancomycin) and drugs (dexamethasone, heparin, furosemide, phenobarbital, albumin, and vitamin K) apparently had no effect on the level and development of gastric lipolytic activities.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcaneal fracture-dislocation with entrapment of the medial neurovascular bundle: a case report

The calcaneus is the most commonly fractured of all the tarsal bones. Soft-tissue interposition, usually involving the peroneal tendons, has been reported to block reduction of calcaneal fractures and subtalar dislocations. To our knowledge, no case of entrapment of the neurovascular bundle has been reported. This is the subject of our report.

Small intestinal mucosa changes, including epithelial cell proliferative activity, of children receiving total parenteral nutrition (TPN)

We examined the small intestinal histology disaccharidase activities as well as the incorporation of [3H]thymidine into DNA of biopsies maintained in organ culture from seven children (ages 9 months to 5 years) receiving total parenteral nutrition (TPN). Three children suffered from inflammatory bowel disease and received TPN for one month (short term). Four required long-term TPN (> 9 months) for short-bowel syndrome. DNA was extracted from the samples following serial precipitation with perchloric acid. Results were compared to those from 22 age-matched children investigated for abdominal pain or chronic diarrhea. Short-term TPN resulted in slightly lower lactase, sucrase, and palatinase activities that were not statistically different from controls. Long-term TPN resulted in focal mild villus atrophy and a decrease in disaccharidase activity in two patients. Biopsies from long-term TPN patients incorporated less thymidine compared to those of controls (P < 0.001) when data was expressed per total biopsy (3.6 +/- 1.1 vs. 8.4 +/- 1.1 fmol) or per milligram of tissue (1.0 +/- 0.12 vs 2.7 +/- 0.7 fmol). The above data are in general agreement with the hypoplastic effect of TPN in animals. However, in children, much longer periods of TPN are required to realize the changes.

Neutrophil adhesion inhibition prolongs survival of cardiac allografts with hyperacute rejection

Hyperacute rejection results in rapid destruction of a cardiac allograft and is characterized by infiltration of neutrophils into the donor organ. We sought to ameliorate this response by using a potent inhibitor of neutrophil adhesion to vascular endothelium, NPC 15669 (N-[9H-(2,7-dimethylfluorenyl-9-methoxy) carbonyl]-L-leucine) and determine its effect on long-term graft survival and histology. This compound specifically prevents recruitment of neutrophils at inflammatory foci by inhibiting upregulation of the CD11b/CD18 adhesion molecule located on the neutrophil surface. Lewis rats were presensitized by three serial ACI rat skin grafts placed 10 days apart. ACI rat hearts were heterotopically transplanted into Lewis recipients 10 to 14 days after the final skin graft. Group I (n = 15) was treated with a 10 mg/kg intravenous bolus of NPC 15669 before reperfusion, followed by 3 mg/kg over 30 minutes. Group II (n = 13) was given saline vehicle intravenously. Two allografts in each group were harvested at 5, 15, 30, and 60 minutes, and the remainder were followed to cessation of graft function. Early 5- to 60-minute allograft histologic findings revealed focal interstitial hemorrhage, edema, and contraction-band necrosis associated with neutrophil infiltration in group II. Group I had significant reduction of all parameters at the earliest time points. Graft survival was significantly increased in group I, 89.2 +/- 20.3 hours (mean +/- SD) compared to 27 +/- 17 hours in group II (p < 0.0001). End-stage rejection was characterized by extensive neutrophil infiltrate and hemorrhage in group II; group I grafts had a predominantly mononuclear cell infiltrate with rare neutrophils.(ABSTRACT TRUNCATED AT 250 WORDS)

Patterns of infant weight gain in developing countries

Data relating to weight of infants from 23 developing countries and two western industrialized populations taken from the literature were compared. Growth in the developing countries was extremely variable, but was poor compared to western standards such that by 12 months of age mean weight in all 23 populations was below the NCHS 50th percentile (P < 0.001) and in 11 populations mean weight was below the 10th percentile. Birth weight was not related to growth increment in the first 3 months. Multiple regression analysis showed birth weight and growth increments in the first four 3-month periods post-partum to be highly significantly related to weight at 12 months (P < 0.0001 in all cases). Growth increment in the first 3 months had the greatest effect out of these variables; the effect of the other four variables was similar. These patterns demonstrate the variable impact of environmental factors on growth in the first year of life.

Down regulation of CYP 1A1 by glucocorticoids in trout hepatocytes in vitro

Short-term culture of rainbow trout (Onchorhynchus mykiss) hepatocytes was used to examine the effect of dexamethasone (DEX) on microsomal CYP 1A1 protein content and 7-ethoxyresorufin-O-deethylase (EROD) activity in vitro. Hepatocytes prepared by controlled collagenase digestion and plated at a density of 0.25 x 10(6) cells/cm2 in plastic culture dishes precoated with trout skin extract (7.6 micrograms skin protein/cm2) to facilitate cell attachment were maintained at 16 degrees C. Cells were treated with DEX (10(-9) to 10(-7) M) or vehicle (dimethyl sulfoxide, DMSO) at 24 h. Microsomal CYP 1A1 protein content and EROD activities were measured at 72 h. Both CYP 1A1 protein as measured by Western blots using CYP 1A1 specific anti-sera and EROD activity were significantly lower in DEX (10(-8) to 10(-7) M)-treated hepatocytes compared to untreated (control) or DMSO-treated cells. The effect was dose dependent in that a gradual decrease of CYP 1A1 protein and EROD activities were seen with increasing doses of DEX (10(-8) to 10(-7) M). DEX at 10(-9) M was ineffective. Concomitant addition of 10(-6) M RU486, a type II specific glucocorticoid receptor antagonist, to hepatocytes treated with 10(-7) M DEX abolished the DEX effect. RU486 at 10(-8) M was ineffective. Spironolactone (10(-8) to 10(-6) M), a type I specific glucocorticoid receptor antagonist, did not counteract the DEX effect. RU486 or spironolactone (10(-6) M) alone had no effect on CYP 1A1 under similar conditions. DEX thus down regulates CYP 1A1 in fish cultured hepatocytes and this regulation is mediated through the type II glucocorticoid receptor(s).

The value of potency testing of poliomyelitis and measles vaccines as an integral part of cold chain surveillance

The Virology Division in the Institute for Medical Research, Kuala Lumpur, Malaysia performs potency tests on oral polio vaccines and live attenuated measles vaccines. Since these potency tests were introduced in 1981 a total of 752 tests have been performed on vaccine samples from peripheral immunization centers. Of 165 representative vaccine samples sent for potency evaluation after a cold chain breakdown 154 (87%) passed minimum potency requirements recommended for immunization of infants. In the absence of potency evaluation, those vaccines exposed to temperatures higher than the recommended storage range would be discarded, perhaps resulting in unnecessary wastage and economic loss. Results of the vaccine potency evaluation has enabled health authorities to indirectly monitor cold chain efficiency and ensure the high quality of viral vaccines used in our childhood immunization program.

34-year-old woman with hypotension, respiratory failure, fever, and an abdominal mass

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Characteristics of a spoiled 6-MV beam from a dual-energy linear accelerator

A beam spoiler for a 6-MV x-ray beam was designed and spoiled beam dosimetry performed. The spoiled beam quality was similar to that of the unspoiled beam. The percentage depth doses at 5 mm were at least 90% for all field sizes except 4 x 4 cm, while the surface dose at 0 mm varied from 22.5% for a 4 x 4-cm field to 85.8% for a 22 x 22-cm field. The spoiled beam showed degraded beam flatness for small field size at superficial depths; the beam flatness at 6 mm for a 4 x 4-cm field was +/- 9.0%. The beam flatness improved as the field size increased, e.g., at same depth, the beam flatness was +/- 2.5% for a 22 x 22-cm field. The penumbra width (90%-10%) of the spoiled beam was greater than that of the unspoiled beam for all field sizes and at all depths; e.g., at 0-mm depth, for a 22 x 22-cm field, the penumbra width was 3.8 cm for the unspoiled beam and 7.2 cm for the spoiled beam. Beyond dmax the difference in the penumbra widths between the spoiled and unspoiled beam was about 3-4 mm for all field sizes and at all depths. The peripheral dose was larger for the spoiled beam.

Patterning of heads and feet during regeneration of Hydra oligactis aggregates

The de novo appearance of head organizing centers was monitored during regeneration of aggregates made from dissociated body column tissue of Hydra oligactis using the head-specific monoclonal antibody CP8 (L. C. Javois, R. D. Wood, and H. R. Bode, 1986, Dev. Biol. 117, 607-618). Newly differentiated CP8+ head organizing centers were present by 24 hr of regeneration and were restricted to one half of the aggregate. Depending on subsequent patterning events these CP8+ cells went on to develop into heads or body tentacles, or remained as CP8+ patches. A comparison of the number of initial CP8+ patches with the final number of CP8+ structures indicated that this number was fairly constant, suggesting that a limited number of head organizing centers were established early during regeneration. Examination of fully differentiated head structures revealed that they were segregated to one end of the aggregate with feet segregated away from the CP8+ structures. Increasing the surface area of the aggregates resulted in a more random initial spacing of CP8+ head organizing centers and ultimately a more random distribution of differentiated heads and feet. However, polarized polyps with one head and foot detached and the remaining structures were then segregated. The ability of existing pattern formation models to describe interactions between head- and foot-forming systems resulting in the observed spacing of heads and feet is discussed.

Negative control of cytochrome P450 1A1 (CYP1A1) by glucocorticoids in rainbow trout liver

1. In rainbow trout liver, dexamethasone caused a reduction in cytochrome P450 1A1 proteins but no change in P450 3A proteins as measured by Western blots using specific anti P450 1A1 and P450 3A sera. 2. After dexamethasone administration, the level of P450 1A1 was down to 14% and 8% of the control values at 24 and 48 hr, respectively. 3. There was no change in P450 1A1 mRNA abundance at 24 hr but a decrease to 45% of the control value was observed at 48 hr after dexamethasone. 4. There is, therefore, a differential response between P450 1A1 and P450 3A to dexamethasone in the trout liver. 5. The initial decrease in P450 1A1 protein probably occurs at the translational level while both translational and transcriptional levels are involved 48 hr after dexamethasone administration.

Thyroidal regulation of lingual lipase development in suckling rats

Rat lingual lipase undergoes maturational increases during postnatal development. The role of thyroxine (T4) in the control of lingual lipase during development was evaluated. T4 given at an early suckling stage (starting day 4 or 5) moderately increased lingual lipase (20-30%) compared to age-matched controls. A similar dose of T4 given later (age > 2 weeks) was ineffective. The T4-sensitive period coincides with a time of low circulating T4, suggesting a role of T4 in modulating the development of lingual lipase in rat pups. Since simultaneous treatment with U486, a type II glucocorticoid receptor antagonist only partially blocked the T4 induction of lingual lipase, T4 appeared to have a direct action on the lingual gland. Pups of propylthiouracil (PTU)-treated dams (previously found to be hypothyroid) showed a delay in the maturation of lingual lipase compared to age-matched pups whose dam was not given PTU. Pups were most sensitive to PTU in the early suckling stage. PTU-induced delayed maturation of lingual lipase was a result of hypothyroidism, since T4 replacement when given early (at the age of 5 days) abolished most of the effect of PTU. When T4 was given later (at the age of 10 days), recovery was much less. This suggests the presence of an early period that is critically dependent on T4 for the full expression of lingual lipase in the rat tongue serous glands.(ABSTRACT TRUNCATED AT 250 WORDS)

Synthesis and biological evaluation of novel potent antagonists of the bombesin/gastrin releasing peptide receptor

This paper reports the synthesis and antagonist activity of 20 C-terminal analogues of gastrin releasing peptide (GRP). The ability of each analogue to inhibit bombesin (BN) stimulated amylase release from rat pancreatic acini was determined, and those showing antagonist activity were further evaluated for their ability to inhibit BN-stimulated [3H]thymidine uptake in serum-starved 3T3 cells. The assays also included two known peptide antagonists, C (Leu14,psi 13,14]BN) and H (N-pivaloyl-GRP20-25-(R)-2-methyl-4-nonylamide) as positive controls. On the basis of these assays we suggest that a des-Met27,Leu26-psi[CH2NHCOCH3]GRP C-terminal octapeptide imparts antagonist activity. The two most active compounds are peptides 14 ([D-Phe19,Leu26-psi(CH2NHCOCH3)]GRP19-26) and 18 ([D-Phe19,Gln20,Leu26-psi(CH2NHCOCH3)]GRP19++ +-26). In their ability to inhibit BN-stimulated [3H]thymidine uptake, the IC50 of peptides C, H, 14, and 18 were 43.2, 31.2, 2.7, and 32.5 nM, respectively. In conclusion, the novel C-terminal psi[CH2NHCOCH3] bond promises to be a useful peptide backbone modification for imparting antagonism in GRP/BN analogues.

Menetrier's disease associated with formula protein allergy and small intestinal injury in an infant

Menetrier's disease in infancy is extremely rare, and its natural course has not been studied in detail. The present case report describes an infant whose initial diagnosis was formula protein allergy and who developed gastric outlet obstruction by 3 months of age. The diagnosis of Menetrier's disease was suggested by characteristic radiological, pathological, and functional abnormalities of the stomach. Small intestinal partial villous atrophy, malabsorption, and protein loss from both the stomach and the intestine were documented. Cytomegalovirus infection was excluded. There was no evidence for an immune deficiency. The described features and an unrelenting course suggest that infantile Menetrier's disease may be an entity distinct from the childhood and adult forms.