ATG16L1 orchestrates interleukin-22 signaling in the intestinal epithelium via cGAS-STING

A coding variant of the inflammatory bowel disease (IBD) risk gene ATG16L1 has been associated with defective autophagy and deregulation of endoplasmic reticulum (ER) function. IL-22 is a barrier protective cytokine by inducing regeneration and antimicrobial responses in the intestinal mucosa. We show that ATG16L1 critically orchestrates IL-22 signaling in the intestinal epithelium. IL-22 stimulation physiologically leads to transient ER stress and subsequent activation of STING-dependent type I interferon (IFN-I) signaling, which is augmented in Atg16l1 ΔIEC intestinal organoids. IFN-I signals amplify epithelial TNF production downstream of IL-22 and contribute to necroptotic cell death. In vivo, IL-22 treatment in Atg16l1 ΔIEC and Atg16l1 ΔIEC/Xbp1 ΔIEC mice potentiates endogenous ileal inflammation and causes widespread necroptotic epithelial cell death. Therapeutic blockade of IFN-I signaling ameliorates IL-22-induced ileal inflammation in Atg16l1 ΔIEC mice. Our data demonstrate an unexpected role of ATG16L1 in coordinating the outcome of IL-22 signaling in the intestinal epithelium.

Acetarsol Suppositories: Effective Treatment for Refractory Proctitis in a Cohort of Patients with Inflammatory Bowel Disease

BACKGROUND

Management of proctitis refractory to conventional therapies presents a common clinical problem. The use of acetarsol suppositories, which are derived from organic arsenic, was first described in 1965. Data concerning clinical efficacy and tolerability are very limited.

AIM

To examine the efficacy of acetarsol suppositories for the treatment of refractory proctitis.

METHODS

A retrospective analysis was performed on patients with inflammatory bowel disease treated with acetarsol suppositories between 2008 and 2014 at Addenbrooke's Hospital, Cambridge, United Kingdom. Clinical response was defined as resolution of symptoms back to baseline at the time of next clinic review.

RESULTS

Thirty-nine patients were prescribed acetarsol suppositories between March 2008 and July 2014 (29 patients with ulcerative colitis, nine with Crohn's disease, and one with indeterminate colitis). Thirty-eight were included for analysis. The standard dose of acetarsol was 250 mg twice daily per rectum for 4 weeks. Clinical response was observed in 26 patients (68%). Of the 11 patients who had endoscopic assessment before and after treatment, nine (82%) showed endoscopic improvement and five (45%) were in complete remission (Wilcoxon signed-rank test p = 0.006). One patient developed a macular skin rash 1 week after commencing acetarsol, which resolved within 4 weeks of drug cessation.

CONCLUSION

Acetarsol was effective for two out of every three patients with refractory proctitis. This cohort had failed a broad range of topical and systemic treatments, including anti-TNFα therapy. Clinical efficacy was reflected in significant endoscopic improvement. Adverse effects of acetarsol were rare.

Pectoral nerve block1 versus modified pectoral nerve block2 for postoperative pain relief in patients undergoing modified radical mastectomy: a randomized clinical trial

BACKGROUND

Pectoral nerve block1 (PEC1) given between pectoralis major and minor, and modified pectoral nerve block2 (mPEC2) performed between pectoralis minor and serratus anterior, can provide continuous analgesia after modified radical mastectomy (MRM) when catheters are placed before skin closure. This study was designed to compare PEC1 and mPEC2 block for providing postoperative pain relief after MRM.

METHODS

Sixty-two physically fit patients undergoing MRM were assigned into two groups (Group PEC1, n=31 and Group mPEC2, n=31). Before wound closure, epidural catheter was placed in the group designated muscle plane and 30ml of 0.25% bupivacaine was injected through the catheter after wound closure. Bupivacaine 15ml of 0.25% top up was given on patient's demand or whenever visual analogue scale (VAS) score was>4. Time for first analgesia (TFA), number of top ups and VAS was recorded at 0.5, 6, 12, 18, 24 h after surgery. Sensory blockade was assessed 30 min after extubation.

RESULTS

Analgesia was significantly prolonged in group mPEC2 [mean(SD)] 313.45(43.05) vs 258.87(34.71) min in group PEC1, P<0.001. Total pain experienced over 24 h was significantly less in group mPEC2 [mean(SD)] 9.77(6.93) than in group PEC1 24.19(10.81), P<0.0001. Consequently, top up requirements were significantly reduced in group mPEC2 than in group PEC1 [median(range)] 3(2-4) vs 4(3-5) respectively, P<0.001. Lateral pectoral (77.42% and 35.48%) and thoracodorsal nerves (93.55% and 48.39%) had higher incidence of sensory block in group mPEC2 than group PEC1, P<0.001.

CONCLUSIONS

mPEC2 provides better postoperative analgesia than PEC1 when catheters are placed under direct vision after MRM.

CLINICAL TRIAL REGISTRATION

CTRI/2017/02/007811 (REF/2015/11/010185).

Defective ATG16L1-mediated removal of IRE1α drives Crohn's disease-like ileitis

ATG16L1^T300A, a major risk polymorphism in Crohn's disease (CD), causes impaired autophagy, but it has remained unclear how this predisposes to CD. In this study, we report that mice with Atg16l1 deletion in intestinal epithelial cells (IECs) spontaneously develop transmural ileitis phenocopying ileal CD in an age-dependent manner, driven by the endoplasmic reticulum (ER) stress sensor IRE1α. IRE1α accumulates in Paneth cells of Atg16l1^ΔIEC mice, and humans homozygous for ATG16L1^T300A exhibit a corresponding increase of IRE1α in intestinal epithelial crypts. In contrast to a protective role of the IRE1β isoform, hyperactivated IRE1α also drives a similar ileitis developing earlier in life in Atg16l1;Xbp1^ΔIEC mice, in which ER stress is induced by deletion of the unfolded protein response transcription factor XBP1. The selective autophagy receptor optineurin interacts with IRE1α, and optineurin deficiency amplifies IRE1α levels during ER stress. Furthermore, although dysbiosis of the ileal microbiota is present in Atg16l1;Xbp1^ΔIEC mice as predicted from impaired Paneth cell antimicrobial function, such structural alteration of the microbiota does not trigger ileitis but, rather, aggravates dextran sodium sulfate-induced colitis. Hence, we conclude that defective autophagy in IECs may predispose to CD ileitis via impaired clearance of IRE1α aggregates during ER stress at this site.

Observation of forbidden exciton transitions mediated by Coulomb interactions in photoexcited semiconductor quantum wells

We use terahertz pulses to induce resonant transitions between the eigenstates of optically generated exciton populations in a high-quality semiconductor quantum well sample. Monitoring the excitonic photoluminescence, we observe transient quenching of the 1s exciton emission, which we attribute to the terahertz-induced 1s-to-2p excitation. Simultaneously, a pronounced enhancement of the 2s exciton emission is observed, despite the 1s-to-2s transition being dipole forbidden. A microscopic many-body theory explains the experimental observations as a Coulomb-scattering mixing of the 2s and 2p states, yielding an effective terahertz transition between the 1s and 2s populations.

Simultaneous time and wavelength resolved spectroscopy under two-colour near infrared and terahertz excitation

Time and wavelength resolved spectroscopy requires optical sources emitting very short pulses and a fast detection mechanism capable of measuring the evolution of the output spectrum as a function of time. We use table-top Ti:sapphire lasers and a free-electron laser (FEL) emitting ps pulses as excitation sources and a streak camera coupled to a spectrometer for detection. One of the major aspects of this setup is the synchronization of pulses from the two lasers which we describe in detail. Optical properties of the FEL pulses are studied by autocorrelation and electro-optic sampling measurements. We discuss the advantages of using this setup to perform photoluminescence quenching in semiconductor quantum wells and quantum dots. Carrier redistribution due to pulsed excitation in these heterostructures can be investigated directly. Sideband generation in quantum wells is also studied where the intense FEL pulses facilitate the detection of the otherwise weak nonlinear effect.

Percutaneous penetration and genotoxicity of 4,4'-methylenedianiline through rat and human skin in vitro

4,4'-Methylenedianiline (MDA) is a primary aromatic amine used in the plastics industry and is classified by the International Agency for Research on Cancer as an animal carcinogen and possible human carcinogen. In order to estimate human exposure it is useful to determine percutaneous penetration. Previous studies have suggested that both rat and human skin were permeable to MDA, with greater penetration being seen through human skin. In this study no significant difference was seen between the percutaneous penetration of MDA through human or rat skin for three different treatment levels: 0.01, 0.1 and 1mg per skin membrane (0.32 cm(2)). The apparent dermal flux was calculated as 0.7 +/- 0.3 and 10.1 +/- 2.0 microg/cm(2)/h for the 0.01 and 0.1mg treatments, respectively. The permeability constant K(p) was estimated at 1.8 x 10(-3) cm/h and the lag time at 3.5 +/- 0.5 h. MDA absorbed into the skin was found to be bioavailable. Experiments also showed that after application of 0.1mg MDA, 4% penetrated through latex and nitrile gloves, respectively. The potential genotoxicity of MDA in human skin was assessed by DNA (32)P-postlabelling; levels of DNA adducts were detected, following the treatment and penetration of 1mg MDA.

Conformational specificity of mini-αA-crystallin as a molecular chaperone

The chaperone activity and biophysical properties of the 19 amino acid peptide DFVIFLDVKHFSPEDLTVK, identified as the functional element in alphaA-crystallin and here referred to as mini-alphaA-crystallin, were studied using light scattering and spectroscopic methods after altering its sequence and enantiomerism. The all-D and all-L conformers of the peptide do not show marked differences in their chaperone-like activity against heat-induced aggregation of alcohol dehydrogenase at 48 degrees C and dithiothreitol-induced aggregation of insulin. The retro peptide does not show any secondary structure and is also unable to act like a chaperone. Both all-L and all-D peptides lose their beta-sheet conformations, hydrophobicity and chaperone-like activity at temperatures > 50 degrees C. However, upon cooling, a significant portion of those properties was regained, suggesting temperature-dependent, reversible structural alterations in the peptides under investigation. We propose that both the hydrophobicity and beta-sheet conformation of the functional element of alphaA-crystallin are essential for chaperone-like activity.

Aggregation of insulin by chlorpromazine

Chlorpromazine (CPZ) is known to induce hyperglycaemia and can inhibit insulin secretion in both normal subjects and patients with latent diabetes mellitus. In this study, we have tried to determine a probable mechanism by which CPZ causes hyperglycaemia. It is possible that CPZ causes insulin aggregation by the reduction of disulphide bonds, thereby inactivating insulin and hence causing hyperglycaemia.

Interactions of chlorpromazine with milk proteins

The mode and nature of the binding of chlorpromazine (CPZ), a psychotropic drug, with milk proteins--alpha-lactalbumin (with substantial amounts of alpha-helix, beta-sheet and random coil), alpha-lactoglobulin (a major beta-sheeted protein) and alphas-casein (a random coiled protein) have been studied spectrofluorometrically and spectropolarimetrically. The binding affinity of CPZ for unfolded proteins is comparatively less than that of folded proteins although the number of binding sites is smaller in the latter case, due to the greater extent of binding of CPZ for folded proteins. Thermodynamic analysis reveals that CPZ binds to alpha-lactalbumin and alphas-casein in an endothermic (deltaH degrees is positive) and hydrophobic manner but with beta-lactoglobulin in an exothermic (deltaH degrees is negative) manner. Far UV Circular dichroic studies reveal that CPZ increases the secondary structure of the major beta-sheeted protein, beta-lactoglobulin possibly by increasing the relative contact orders (non-local contacts) within the residues. On the other hand, for proteins possessing random coil, it increases the unfolded state of the protein. CPZ does not affect local contacts in alpha-helix when its interaction is compared with a major alpha-helical protein, myoglobin.

Studies on the effects of lipopolysaccharide on lipid peroxidation of erythrocyte and its reversal by mannitol and glycerol

Gram-negative sepsis often produces endotoxin (LPS) which causes infection. Reduction in tissue perfusion due to microcirculatory failure may lead to septic shock. We studied the effect of LPS on lipid peroxidation of erythrocyte. In vitro studies using 50 microg to 250 microg LPS/ml blood showed increased lipid peroxidation of erythrocyte in a dose-dependent manner. The increased effect of lipid peroxidation does not occur with LPS when erythrocytes were washed to remove plasma and leukocytes. Mannitol and glycerol, known scavengers of hydroxyl radical, arrest the elevation in lipid peroxidation of erythrocytes after LPS treatment. Hemolysis of erythrocytes was reduced with low doses of LPS. Plasma lipid peroxidation was elevated after treatment of blood with LPS. From the results we suggest that the peroxidation of erythrocyte lipid caused by LPS may probably play a role in the production of septic shock.

Validity of mechanism of gene transfer in the process called conjugation in bacteria

We have attempted a new evaluation of the process of conjugation in bacteria, because of some basic dissimilarities observed between this and that of eukaryotes, or plants and animals. Reference donor and recipient strains, widely used to prove conjugation in bacteria, were chosen; addition of DNase during the conjugation process, led to an unexpected but highly reproducible increase in the transconjugant colony counts (TCC; ca. > or = 1 log), when compared with that of the controls without DNase. Transconjugants were also obtained when the same live donors were substituted with the UV-killed ones although the TCC was very low initially. Contrarily, donors treated with DNA-intercalating agents, e.g. acridine orange or ethidium bromide, resulted in a complete failure to produce transconjugants. There was a quantitative relationship between the DNase used on donors and levels of DNA sugars/nucleotides/DNA, which possibly resulted from interaction between the DNase and DNA being present/produced on the donor surface. This may be indicative of what may actually happen in the donor-recipient mixtures in the conjugation test proper, where the recipient DNase may activate a donor DNA production cycle. The evidences presented did not suggest that the donor DNA in the conjugation process is actually vestibuled through any intercellular conjugation passages, and is susceptible to the action of DNase or the intercalating dyes.

Effect of endotoxin on protein degradation and lipid peroxidation of erythrocytes

Sepsis has often been associated with infection due to endotoxin (LPS) produced from gram-negative bacteria. Microcirculatory failure is one of the ultimate causes of septic shock. We studied the effect of endotoxin on the protein breakdown and lipid peroxidation of erythrocyte. In vivo (20 ug LPS/100 g) studies in rats showed increased tyrosine production from erythrocyte, as an index of protein degradation in erythrocyte. In vitro studies using 25 microg to 250 microg LPS per ml also showed similar type of increased effect of endotoxin in protein degradation. Washed erythrocyte devoid of plasma and leucocytes did not show any increased effect after endotoxin treatment. Lipid peroxidation was also increased after endotoxin treatment. However, protein degradation was more prominent than lipid peroxidation. We concluded therefore that the protein degradation and lipid peroxidation of erythrocytes caused by endotoxin are probably related to the production of septic shock.

Molecular chaperone-like properties of an unfolded protein, alpha(s)-casein

All molecular chaperones known to date are well organized, folded protein molecules whose three-dimensional structure are believed to play a key role in the mechanism of substrate recognition and subsequent assistance to folding. A common feature of all protein and nonprotein molecular chaperones is the propensity to form aggregates very similar to the micellar aggregates. In this paper we show that alpha(s)-casein, abundant in mammalian milk, which has no well defined secondary and tertiary structure but exits in nature as a micellar aggregate, can prevent a variety of unrelated proteins/enzymes against thermal-, chemical-, or light-induced aggregation. It also prevents aggregation of its natural substrates, the whey proteins. alpha(s)-Casein interacts with partially unfolded proteins through its solvent-exposed hydrophobic surfaces. The absence of disulfide bridge or free thiol groups in its sequence plays important role in preventing thermal aggregation of whey proteins caused by thiol-disulfide interchange reactions. Our results indicate that alpha(s)-casein not only prevents the formation of huge insoluble aggregates but it can also inhibit accumulation of soluble aggregates of appreciable size. Unlike other molecular chaperones, this protein can solubilize hydrophobically aggregated proteins. This protein seems to have some characteristics of cold shock protein, and its chaperone-like activity increases with decrease of temperature.

Alpha-crystallin does not require temperature activation for its chaperone-like activity

alpha-crystallin acts as a molecular chaperone by preventing the aggregation of proteins. Although the mechanism for this activity is not understood there is a proposition that temperature activation at or above 30 degrees C of alpha-crystallin is an absolute requirement, thereby suggesting a conformational transition as a trigger for the activity. In an attempt to unravel the putative temperature-activity relationship, the chaperone-like activity of alpha-crystallin was studied at a number of temperatures above and below 30 degrees C. Chaperone activity was monitored against aggregation of the insulin-B chain induced by cleavage of disulfide bond of insulin and also against photo-aggregation of gamma-crystallin. Contrary to the above notion, the results indicate that alpha-crystallin does not require thermal activation for its chaperone function and that it can efficiently function as a molecular chaperone even at temperatures below the previously reported transition temperature.

Structural organisations of hemoglobin and myoglobin influence their binding behaviour with phenothiazines

Binding modalities of chlorpromazine and trifluoperazine, two widely used antipsychotic phenothiazine drugs with hemoglobin and myoglobin have been studied to understand how the quaternary, tertiary and secondary structural organisations of the proteins regulate the binding process. NaCl-induced alteration in the quaternary structure of hemoglobin influences its binding modality with phenothiazines. Minor alterations in the tertiary structure of thermally denatured myoglobin (denaturation temperature ranging between 30-70 degrees C) do not affect its affinity and the modality of binding with the drugs, but alterations in the secondary structure of the protein denatured at temperatures between 70-80 degrees C influence its binding.

Dioflorin, a Minor Flavonoid from Dioclea grandiflora

Dioflorin (1) was isolated as a minor constituent from the rootbark of Dioclea grandiflora, the crude extract of which demonstrated analgesic activity. The structure of 1 has been determined to be 5,7,2'-trihydroxy-8-methoxy-6-(3-methyl-2-butenyl)flavanone on the basis of spectral analysis.

Alterations in intracellular calcium during sepsis

Tissue injury and/or infection produce significant alterations in intracellular calcium ion regulation. These alterations in cellular calcium has recently been studied following both short term and long term septic model which uses two types of gram-negative bacteria frequently encountered human abdominal sepsis. Changes in calcium flux as well as functional disturbances has been observed in the major organs, specially in skeletal muscle. The changes in calcium flux in different organs were studied using 45Ca exchange, 19F NMR study or by using calcium-fluorescence probes. Calcium-channel blockers attenuate the increased effects of calcium flux. Further anti-cytokines may be useful to prevent septic injury in tissues.

Trifluoperazine is more effective than chlorpromazine in releasing oxygen from haemoglobin and myoglobin

The extent of oxygen release from two heme proteins, haemoglobin and myoglobin have been studied in the presence of trifluoperazine and chlorpromazine (5-1000 microM). At a molar ratio (drug:protein) of 1.5, the release of oxygen from haemoglobin was 4 and 15% in the presence of chlorpromazine and trifluoperazine respectively, while from myoglobin the corresponding values were 20 and 40%. The findings were attributed to the greater extent of local conformational change around tryptophan moieties of each of the proteins induced by trifluoperazine.

Analgesic effect of Dioclea grandiflora constituents in rodents

An aqueous fraction and dioclein (5,2',5'-trihydroxy-6,7-dimethoxyflavanone) obtained from the ethanolic extract of the Dioclea grandiflora were tested for their analgesic effect in mice and rats employing acetic-induced writhing and tail flick tests, respectively. When administered intraperitoneally the two agents exhibited significant analgesic effects. The activity of both dioclein and aqueous fraction apparently involves an opiate-like mechanism, since their analgesic action was attenuated by naloxone pretreatment.

Interaction of chlorpromazine with myoglobin and hemoglobin. A comparative study

The mode and nature of the binding of chlorpromazine (CPZ), a psychotropic drug, with myoglobin, a monomeric muscle protein, were studied spectrofluorometrically and the results compared with those from the binding of CPZ to hemoglobin, a tetrameric allosteric protein from red blood cells (RBC). CPZ interacted with myoglobin in a non-cooperative mode, with a binding constant of 8.4 x 10(3) M-1 in 0.145 M NaCl, pH 6.8, whereas in the case of hemoglobin this interaction was found to be positively cooperative with a binding constant of 4.2 x 10(3) M-1. The interaction of CPZ with myoglobin was not influenced by the NaCl molarity of the solution, whereas CPZ interaction with hemoglobin significantly decreased with increasing NaCl molarity, indicating that CPZ-hemoglobin binding is mostly electrostatic in nature, whereas that of the CPZ-myoglobin complex is of a non-electrostatic type. Thermodynamic analysis revealed that binding of CPZ to hemoglobin was exothermic (delta H degrees = -2.65 kcal/mol), whereas binding to myoglobin was endothermic (delta H degrees = + 1.39 kcal/mol) with a high entropic contribution (delta S degrees = +23 cal/degree/mol), suggesting that CPZ binding to myoglobin is hydrophobic in nature. Such contrasting binding features of this drug have been discussed in the light of a typical subunit interaction property present and absent in hemoglobin and myoglobin, respectively.

Skeletal muscle Ca2+ flux and catabolic response during sepsis

Membrane Ca2+ flux and net protein catabolism were studied in the skeletal muscle during experimental sepsis. Sterilized rat fecal pellets with (septic) or without (sterile) gram-negative bacteria, Escherichia coli [10(2) colony-forming units (cfu)] and Bacteroides fragilis (2 x 10(3) cfu), were implanted into the abdomens of male Sprague-Dawley rats (110-120 g). Septic and sterile rats were febrile and hyperlactacidemic on day 1 postimplantation. These responses subsided by day 2 in sterile but not septic rats. Initial Ca2+ flux, estimated from measurements of 45Ca uptake by soleus muscles in vitro, was elevated on day 1 in both sterile and septic rats and on day 2 and 3 in septic rats only. The septic rat soleus muscle showed a significantly increased net protein catabolic response (measured as tyrosine release by soleus muscle, in vitro) over that found in muscles of sterile rats on day 1-3 postimplantation. The increase in Ca2+ flux in septic (day 1-3 postimplantation) and sterile (day 1 only) rats was abolished when the rats were treated with the calcium channel blocker diltiazem. In unoperated control rat soleus muscles the Ca2+ ionophore, ionomycin, concomitantly caused an increase in Ca2+ flux and net protein catabolism. Overall, the present study suggested that altered cellular Ca2+ regulation plays a role in the net protein catabolic response in the skeletal muscle during sepsis.

Longitudinal study on distribution of Phlebotomus argentipes sandflies at different heights in cattleshed

Distribution of Ph. argentipes at three levels (level I, 0-0.91 m; level II, 0.91-1.82 m; and level III 1.82-2.74 m) above the ground in 6 cattlesheds was studied during July 1989 to June 1990. Of the 8044 Ph. argentipes caught, 3151 (39.2%), 3936 (48.9%) and 957 (11.9%) were from levels I, II, and III respectively. Both male and fed, half-fed, gravid and unfed female sandflies were found at all the three levels and in all the three seasons viz., rainy, winter and summer, of the year. The maximum height of occurrence of sandflies was 2.51 m (8.3 ft) above the ground level.

Chemical and pharmacological investigation of Solanum species of Brazil--a search for solasodine and other potentially useful therapeutic agents

A systematic search for solasodine, an important starting material for the partial synthesis of steroidal hormones as well as other potentially bioactive constituents of various Solanum species of Brazil has been undertaken. Thus, the fruits of S. paludosum, S. asperum, S. sessiliflorum and Solanum sp. were found to contain significant amounts of solasodine. The root bark of S. paludosum which showed curare like activity yielded tomatidenol and another yet unidentified alkaloid responsible for the biological activity. The fruits of S. asperum yielded a new spirosolane alkaloid, solaparnaine. The stem bark of S. pseudo-quina showed convulsive and excitatory activity from which (25S)-isosolafloridine was identified as the active principle. In addition, the latter alkaloid was also found to show antimicrobial activity.

Alpha 1-antitrypsin: a possible tool for diagnosis of cervical cancer

The serum protease inhibitor alpha 1-AT was measured in patients with different types of cancer and compared with that of normal human serum. alpha 1-AT levels, as measured by its trypsin inhibitory capacity and the immunodiffusion technique, showed significant increase (P less than 0.05 and P less than 0.001, respectively) in cervical cancer patients. The results indicates that levels of alpha 1-AT may have a direct relationship with cervical cancer condition.

The effect of submaxillariectomy on the uterine peroxidase activity and [14C]phenylalanine incorporation into uterine protein in rats

Surgical removal of submaxillary glands in immature female rats caused an increase in size and about 3-fold increase in dry and wet weight of the uterus compared to that of the sham operated animals of the same age group. Histological examination reveal a significant increase in the diameter of the uterus with considerable elongation of the luminal epithelium from cubical to columnar in the experimental group. Biochemical studies showed that the uterine peroxidase, a marker enzyme for oestrogen action, increased (P less than 0.01) on submaxillariectomy. Incorporation of [14C]phenylalanine into the nuclear fraction of uterus was also enhanced significantly on removal of submaxillary glands. The elevation of peroxidase activity as well as of [14C]phenylalanine incorporation into the nuclear fraction due to removal of submaxillary glands were abolished in ovariectomized rats suggesting the involvement of ovarian hormones. The results show that oestrogen was responsible for all the above mentioned changes, whereas progesterone had little effect. Results further suggest the existence of a factor in the submaxillary glands through which they exert an effect on the uterus and ovary.

Effect of cold exposure on the amylase activity of submaxillary gland of rats

Cold exposure of rats for 3 h (6 +/- 2 degrees C) caused an increase in amylase activity of the submaxillary gland. This effect was not observed in other salivary glands i.e. parotid and sublingual or in the pancreas. The increase of amylase activity during cold exposure was completely abolished by the beta-receptor antagonist, propranolol, and the alpha-receptor antagonist, phenoxybenzamine, reduced the effect. Administration of actinomycin D to the cold-exposed rats produced a tremendous increase of enzyme activity instead of abolition of the increase as had been expected.

Uterine changes on removal of submaxillary glands in rats (histological changes/uterine peroxidase/blood estradiol level)

Surgical removal of submaxillary gland in immature rats causes a large increase in size and about three to four fold increase in dry and wet weight of uterus compared to that of the sham operated animals of the same age group. Histological examination reveals a significant increase in the diameter of the uterus with considerable elongation of the luminal epithelium from cubical to columnar in the experimental group. Biochemical studies show that the uterine peroxidase (donor: hydrogen-peroxide oxidoreductase, EC 1.11.1.7), a marker enzyme for uterine growth, increases by ten to fifteen fold on submaxillariectomy and returns almost to the normal level on administration of submaxillary gland extract (105,000 X g supernatant) to the submaxillariectomized animals. Estrogen estimation by radioimmunoassay shows a similar increase of three to four fold on removal of submaxillary glands and decrease almost to the normal value on administration of the submaxillary extract.

Effect of cold exposure on peroxidase and iodinase activities of rat submandibulary gland

Exposure of rats to 6 +/- 2 degrees C for 3 h caused an increase in peroxidase activity (55%) and tyrosine iodinase activity (40%) of the submandibulary glands. Thiocyanate, hydrogen peroxide and formation of triiodide from iodide were also elevated under the same conditions. Administration of alpha-receptor blockers and indomethacin prevented the rise of peroxidase activity during cold stress whereas beta-receptor blockers were less effective.

Constituents of Spartina cynosuroides: isolation and 13C-NMR analysis of tricin

Tricin was isoalted from the aerial parts of the marsh plant Spartina cynosuroides, which yielded a fraction enriched in antiluekemic activity. The 13C-NMR spectrum of tricin is discussed.