The effects of capsaicin on gastrin secretion in isolated human antral glands: before and after ingestion of red chilli.

BACKGROUND: Capsaicin is known to have regulatory effects on gastrointestinal functions via the vanilloid receptor (VR1). We reported previously that endocrine-like cells in the human antrum express VR1. AIM: To identify VR1-expressing endocrine-like cells in human antral glands and to examine whether stimulation with capsaicin causes release of gastrin, somatostatin, and serotonin. Further, to investigate the effects of a chilli-rich diet. METHODS: Gastroscopic biopsies were received from 11 volunteers. Seven of the 11 subjects agreed to donor gastric biopsies a second time after a 3-week chilli-rich diet containing 1.4-4.2 mg capsaicin/day. VR1-immunoreactive cells were identified by double-staining immunohistochemistry against gastrin, somatostatin, and serotonin. For the stimulation studies, we used an in vitro method where antral glands in suspension were stimulated with 0.01 mM capsaicin and physiological buffer was added to the control vials. The concentrations of secreted hormones were detected and calculated with radioimmunoassay (RIA). Results The light microscopic examination revealed that VR1 was localized in gastrin cells. The secretory studies showed an increase in release of gastrin and somatostatin compared to the control vials (P = 0.003; P = 0.013). Capsaicin-stimulation caused a consistent raise of the gastrin concentrations in the gland preparations from all subjects. A chilli-rich diet had an inhibitory effect on gastrin release upon stimulation compared to the results that were obtained before the start of the diet. CONCLUSION: This study shows that capsaicin stimulates gastrin secretion from isolated human antral glands, and that a chilli-rich diet decreases this secretion.

Corticotropin-releasing hormone (CRH) regulates macromolecular permeability via mast cells in normal human colonic biopsies in vitro.

OBJECTIVE: Persistent stress and life events affect the course of ulcerative colitis and irritable bowel syndrome by largely unknown mechanisms. Corticotropin-releasing hormone (CRH) has been implicated as an important mediator of stress-induced abnormalities in intestinal mucosal function in animal models, but to date no studies in human colon have been reported. The aim was to examine the effects of CRH on mucosal barrier function in the human colon and to elucidate the mechanisms involved in CRH-induced hyper-permeability. DESIGN: Biopsies from 39 volunteers were assessed for macromolecular permeability (horseradish peroxidase (HRP), (51)Cr-EDTA), and electrophysiology after CRH challenge in Ussing chambers. The biopsies were examined by electron and confocal microscopy for HRP and CRH receptor localisation, respectively. Moreover, CRH receptor mRNA and protein expression were examined in the human mast cell line, HMC-1. RESULTS: Mucosal permeability to HRP was increased by CRH (2.8+/-0.5 pmol/cm(2)/h) compared to vehicle exposure (1.5+/-0.4 pmol/cm(2)/h), p = 0.032, whereas permeability to (51)Cr-EDTA and transmucosal electrical resistance were unchanged. The increased permeability to HRP was abolished by alpha-helical CRH (9-41) (1.3+/-0.6 pmol/cm(2)/h) and the mast cell stabilizer, lodoxamide (1.6+/-0.6 pmol/cm(2)/h). Electron microscopy showed transcellular passage of HRP through colonocytes. CRH receptor subtypes R1 and R2 were detected in the HMC-1 cell line and in lamina propria mast cells in human colon. CONCLUSIONS: Our results suggest that CRH mediates transcellular uptake of HRP in human colonic mucosa via CRH receptor subtypes R1 and R2 on subepithelial mast cells. CRH-induced macromolecular uptake in human colon mucosa may have implications for stress-related intestinal disorders.

Fusion of radiostereometric analysis data into computed tomography space: application to the elbow joint.

Improvement of joint prostheses is dependent upon information concerning the biomechanical properties of the joint. Radiostereometric analysis (RSA) and electromagnetic techniques have been applied in previous cadaver and in vivo studies on the elbow joint to provide valuable information concerning joint motion axes. However, such information is limited to mathematically calculated positions of the axes according to an orthogonal coordinate system and is difficult to relate to individual skeletal anatomy. The aim of this study was to evaluate the in vivo application of a new fusion method to provide three-dimensional (3D) visualization of flexion axes according to bony landmarks. In vivo RSA data of the elbow joint's flexion axes was combined with data obtained by 3D computed tomography (CT). Results were obtained from five healthy subjects after one was excluded due to an instable RSA marker. The median error between imported and transformed RSA marker coordinates and those obtained in the CT volume was 0.22 mm. Median maximal rotation error after transformation of the rigid RSA body to the CT volume was 0.003 degrees . Points of interception with a plane calculated in the RSA orthogonal coordinate system were imported into the CT volume, facilitating the 3D visualization of the flexion axes. This study demonstrates a successful fusion of RSA and CT data, without significant loss of RSA accuracy. The method could be used for relating individual motion axes to a 3D representation of relevant joint anatomy, thus providing important information for clinical applications such as the development of joint prostheses.

Maternal and perinatal risk factors for childhood leukemia.

This report describes an exploratory population-based study of maternal and perinatal risk factors for childhood leukemia in Sweden. The Swedish National Cancer Registry ascertained 411 cases in successive birth cohorts from 1973 through 1984 recorded in the Swedish Medical Birth Registry. Using the latter, we matched five controls without cancer to each case by sex and month and year of birth. Mothers of children with leukemia were more likely to have been exposed to nitrous oxide anesthesia during delivery than mothers of controls [odds ratio (OR) = 1.3; 95% confidence interval (CI) = 1.0, 1.6]. Children with leukemia were more likely than controls to have Down's syndrome (OR = 32.5; 95% CI = 7.3, 144.0) or cleft lip or cleft palate (OR = 5.0; 95% CI = 1.0, 24.8); to have had a diagnosis associated with difficult labor but unspecified complications (OR = 4.5; 95% CI = 1.1, 18.2) or with other conditions of the fetus or newborn (OR = 1.5; 95% CI = 1.1, 2.1), specifically, uncomplicated physiological jaundice (OR = 1.9; 95% CI = 1.2, 2.9); or to have received supplemental oxygen (OR = 2.6; 95% CI = 1.3, 1.3, 4.9). Because multiple potential risk factors were analyzed in this study, future studies need to check these findings. We did not confirm the previously reported higher risks for childhood leukemia associated with being male, having a high birth weight, or being born to a woman of advanced maternal age.

Fine structural organization of spinothalamic and trigeminothalamic lamina I terminations in the nucleus submedius of the cat.

We examined lamina I trigemino- and spinothalamic tract (TSTT) terminals labeled with Phaseolus vulgaris leucoagglutinin in the nucleus submedius (Sm), a nociceptive relay in the cat's thalamus. Volume-rendered (three-dimensional) reconstructions of ten lamina I TSTT terminals identified with light and electron microscopy were built from serial ultrathin sections by computer, which enabled the overall structures of the terminal complexes to be characterized in detail. Two fundamentally different terminations were observed: compact clusters of numerous boutons, which predominate in the dense focus of a lamina I terminal field in the Sm, and boutons-of-passage, which are present throughout the terminal field and predominate in its periphery. Reconstructions of cluster terminations reveal that all boutons of each cluster make synaptic contact with protrusions and branch points on a single dendrite and involve presynaptic dendrites (PSDs) in triadic arrangements, providing a basis for the secure relay of sensory information. In contrast, reconstructions show that boutons-of-passage are generally characterized by simple contacts with PSDs, indicating an ascending inhibitory lamina I influence. These different synaptic arrangements are consistent with physiological evidence indicating that the morphologically distinct nociceptive-specific and thermoreceptive-(cold)-specific lamina I TSTT neurons terminate differently within the Sm. Thus, a suitable structural substrate exists in the cat's Sm for the inhibitory effect of cold on nociception, a behavioral and physiological phenomenon of fundamental significance. We conclude that the Sm is more than a simple relay for nociception, and that it may be an integrative comparator of ascending modality-selective information that arrives from neurons in lamina I.

Synaptology of trigemino- and spinothalamic lamina I terminations in the posterior ventral medial nucleus of the macaque.

We used the electron microscope to examine lamina I trigemino- and spinothalamic (TSTT) terminations in the posterior part of the ventral medial nucleus (VMpo) of the macaque thalamus. Lamina I terminations were identified by anterograde labeling with biotinylated dextran, and 109 boutons on 38 terminal fibers were closely studied in series of ultrathin sections. Five unlabeled terminal boutons of similar appearance were also examined in detail. Three-dimensional, volume-rendered computer models were reconstructed from complete series of serial sections for 29 boutons on 10 labeled terminal fibers and one unlabeled terminal fiber. In addition, postembedding immunogold staining for GABA was obtained in alternate sections through 23 boutons. Lamina I TSTT terminations in VMpo generally have several large boutons (mean length = 2.16 microm, mean width = 1.29 microm) that are densely packed with vesicles and make asymmetric synaptic contacts on low-order dendrites of VMpo neurons (mean diameter 1.45 microm). They are closely associated with GABAergic presynaptic dendrites (PSDs), and nearly all form classic triadic arrangements (28 of 29 reconstructed boutons). Consecutive boutons on individual terminal fibers make multiple contacts with a single postsynaptic dendrite and can show evidence of progressive complexity. Dendritic appendages that enwrap and invaginate the terminal bouton constitute additional anatomic evidence for secure, high-fidelity synaptic transfer. These observations provide direct ultrastructural evidence supporting the hypothesis that VMpo is a lamina I TSTT thalamocortical relay nucleus in primates that subserves pain, temperature, itch, and other sensations related to the physiological condition of the body.

GABA-like immunoreactivity in the thalamic nucleus submedius of the cat.

The distribution of GABAergic elements and their synaptic contacts in the nucleus submedius, a specific nociceptive relay in the medial thalamus of the cat, was studied using light and electron-microscopic postembedding immunohistochemical methods. About one-fourth of the neurons in nucleus submedius were GABA immunoreactive. These neurons were generally smaller than the unlabeled neurons and are probably local circuit neurons. Electron microscopy showed GABA immunoreactivity in two types of vesicle-containing profiles, F-terminals and presynaptic dendrites. F-terminals formed simple synapses with the dendrites of presumed thalamocortical relay cells. Presynaptic dendrites were involved in more complex synaptic arrangements that included ascending trigeminothalamic and spinothalamic tract terminals and thalamocortical relay cell dendrites. Analysis of single sections showed that about 40% of the trigeminothalamic and spinothalamic tract terminals, identified by anterograde transport of horseradish peroxidase, were presynaptic to GABAergic presynaptic dendrites. These results show that GABAergic neurons are frequent in nucleus submedius and that the GABAergic elements make synaptic connections similar to those described for other sensory relay nuclei, including the somatosensory ventroposterior nucleus. This suggests that GABAergic mechanisms play an important role in the processing of nociceptive and thermoreceptive information.

An analysis of the inhibition of replication of HIV and MuLV by some 3'-blocked pyrimidine analogs.

Some 3'-blocked pyrimidine analogs were synthesized and tested as inhibitors of replication of human immunodeficiency virus (HIV) and Moloney-murine leukemia virus (MuLV). The analogs were of 3 kinds: (1) analogs of 3'-azido-3'-deoxythymidine (AZT) in which the C-5 CH3 of the base was exchanged for H (AZU) or C2H5 (AZEU); (2) 3'-fluoro-3'-deoxythymidine (FLT) and analogs thereof, in which the C-5 CH3 of the base was exchanged for H (FLU), C2H5 (FLEU) or nC3H7 (FLPU); (3) the threo analogs of AZT (AZT increases) and AZU (AZU increases). All analogs were less active inhibitors of HIV replication than AZT, except FLT, which was as active as AZT. The 3'-fluoro analogs and AZEU did not inhibit MuLV replication at non-cytotoxic concentrations. Oral administration of FLT to MuLV-infected mice result in antiviral effects only at toxic drug levels. AZU and FLU were less potent inhibitors of HIV replication than AZT or FLT, but the 2'-deoxy uridine analogs were less cytotoxic to human embryonic fibroblasts than the thymidine analogs. The 5'-triphosphates of AZU, AZT, AZEU, FLT and FLEU were tested as inhibitors of the HIV- and MuLV-reverse transcriptases. Ranking of the Ki/Km values for HIV-RT resulted in the following order of potency of the 5'-triphosphates AZT = FLT greater than AZU greater than AZEU greater than FLEU. The 5'-triphosphates of AZEU, FLT and FLEU did not inhibit the MuLV-RT, which explains, in part, the lack of effect of these analogs against MuLV replication. The threo forms (azido "up") of AZU and AZT were less active inhibitors of HIV replication than the erythro forms (azido "down"). A 15N-NMR and 1H-NMR study showed that the furanose moieties of analogs with the azido function "up" assume a conformation distinct from that of the analogs with azido "down". This is due to intramolecular stabilisation of the "N" conformer in the threo ("up") diastereomer, due to interaction of the azido functions with the nucleobase and possibly the OH group of C-5' of the furanose. As discussed, this conformation might explain the decreased biological activity of threo forms compared with the erythro forms.

Critical determinants of antiherpes efficacy of buciclovir and related acyclic guanosine analogs.

Buciclovir is an example of an antiherpes, acyclic guanosine analog activated by the viral thymidine kinase and inhibiting viral DNA synthesis in infected cells. An investigation of closely related buciclovir-analogs with similar antiherpes activities in cell cultures and similar, or identical, modes of action but with disparate effects in vivo, revealed the following critical determinants of antiherpes efficacy. (1) The accumulation of guanosine analog-triphosphates in infected cells, which is cell-type-specific and analog-dependent. (2) The potencies of the triphosphates as inhibitors of the viral DNA polymerase. (3) The plasma kinetics of the analogs, which are widely different despite the similar structures. (4) The penetration into nervous tissue relative to penetration into non-nervous tissues, of importance in connection with the neurotropic behavior of the virus. (5) The concentration of the antagonist thymidine in certain tissues. (6) The difference in pathogenesis between primary infections and recurrent infections, exemplified in the different efficacies of topically applied drugs in cutaneous and genital HSV-2 infections in guinea pigs.

Impact of changing age and parity distributions of mothers on perinatal mortality in Sweden, 1953-1975.

A study was made on how the shift in the age and parity distribution of mothers affected the perinatal mortality in Sweden between 1953-55 and 1973-75. During these years the overall perinatal mortality rate fell from 29 to 13 per 1 000 births. The authors used the specific perinatal mortality rates by the mother's age and infant's birth order in 1973-75 to calculate what the overall perinatal mortality rate would have been with the age and parity distributions of mothers in 1953-55 and 1963-65. They conclude that only 1.4 of the 16 per 1 000 decline in perinatal mortality could be attributed to the shift in the mother's age and parity distribution.

Surveillance of malformations at birth: a comparison of two record systems run in parallel.

The efficiency of two national record systems for malformation monitoring has been compared. During 1973 and 1974, two such registers were run in parallel in Sweden. One is based on specific report cards which are sent in when a malformed infant is born, the other is a computerised analysis of routine birth record diagnoses. Both systems lose a similar, and significant, proportion of malformed infants. The quality of diagnosis is lower in the system of routine birth records than in the system based on specific notifications--especially in infants with multiple malformations or with reduction malformations of the limbs. The specific report system is the only one suitable for monitoring of malformations; it is also somewhat quicker than the other system.

Maternal smoking in pregnancy: does it increase the risk of childhood cancer?

Experimental studies show that some compounds in tobacco smoke are transplacental carcinogens, but epidemiological data on maternal smoking and childhood cancer are inconclusive. Using the national Swedish Medical Birth and Cancer Registries, the incidence of cancer was followed through 1987 in a cohort of 497,051 children born 1982-1987 for whom information was available on maternal smoking at 2-3 months of pregnancy. A total of 327 cancers appeared including 198 solid tumours and 129 cancers of the lymphatic and haematopoietic system. The overall relative risk for cancer in children with mothers reporting smoking during pregnancy was 0.99 (95% confidence interval (CI): 0.78-1.27). Corresponding risks for solid tumours and cancers of the lymphatic/haematopoietic system were 0.96 (0.70-1.32) and 1.04 (0.71-1.52), respectively. There was no consistent increase in risk for cancer of different sites or in relation to number of cigarettes smoked per day.

Electron microscopic identification of lamina I axon terminations in the nucleus submedius of the cat thalamus.

Ascending lamina I axons were labeled with Phaseolus vulgaris leucoagglutinin and the synaptic connections of their terminals in nucleus submedius (Sm) were studied in the electron microscope. The terminals were large, contained rounded synaptic vesicles, and were involved in complex synaptic aggregations with pre- and postsynaptic dendrites. It was observed that clustered large boutons from a single axon could contact a single dendritic shaft. These observations support a sensory role for lamina I input to Sm.

Neonatal exposure to substance P alters behavioral and substance P levels in the central nervous system of the adult rat.

Substance P (SP) administered subcutaneously to male and female rats during a neonatal period (days 1-7 after birth), produced long-term effects. Thermal/pain perception and elements of both male and female copulatory behavior were altered. A significant increase in the SP level in the dorsal part of the spinal cord was demonstrated by radioimmunoassay and by micro-fluorescence. The present study indicates that exposure to SP during the neonatal period, when the role of SP in transmission is likely to be established, has biochemical and functional consequences for SP systems in the adult.

AMPA-selective glutamate receptor subunits and their relation to glutamate- and GABA-like immunoreactive terminals in the nucleus submedius of the rat.

Glutamate plays an important role in supraspinal nociceptive systems. Thus, glutamate is present in the nucleus submedius of the medial thalamus, a major relay for nociceptive information. In this study, immunoreactivity for the four subunits (GluR1-4) of alpha-amino-3-hydroxy-5-methyl-4-isoxasoleproprionate (AMPA) receptors was examined by a preembedding immunohistochemical method in order to evaluate the presence of this glutamate receptor subtype in the nucleus submedius. Combining the preembedding method with a postembedding immunogold technique, we found that AMPA receptor-like immunoreactivity was present postsynaptically to glutamatergic terminals but not to terminals containing gamma-aminobutyric acid (GABA). These findings suggest a role for AMPA receptors in excitatory synaptic transmission in the nucleus submedius of the rat thalamus.

A systematic study of nucleotide analysis of human erythrocytes using an anionic exchanger and HPLC.

A two-step procedure for rapid HPLC analysis of nucleotides from human erythrocytes is described. A strong anion exchanger Partisil-10 is used as column material. Elution of monophosphates requires about 12 min and the elution of di- and triphosphates 21 min. The elutions are performed separately and with different injections as such a procedure will save time otherwise used to re-condition the columns. In addition to the three adenylates other nucleotides such as GTP, GDP, IMP and NAD can be recorded as isolated, well-defined peaks, which can be subject to quantitative analysis. The mean value of ATP concentration for 12 healthy individuals was 1.55 +/- 0.05 mmol/l, about 25% higher than generally reported in the literature. Accurate estimates of ADP and AMP concentrations allowed calculation of mean values for the physiologically interesting ratios: adenylate energy charge (0.945 +/- 0.002) and equilibrium constant for adenylate kinase (1.205 +/- 0.053). GDP and GTP are present in concentrations that are about 4% of those for corresponding adenylates. The analysis of nucleotides in human erythrocytes is a useful way of studying erythrocyte preservation and investigating patients with hemolytic disorders.

Erythrocyte nucleotide pattern in two children in a Norwegian family with pyrimidine 5'-nucleotidase deficiency.

In the erythrocytes from two Norwegian children, a brother and a sister, with a hemolytic anemia due to pyrimidine 5'-nucleotidase deficiency, the pyrimidine and purine nucleotides have been investigated using HPLC with a strong anionic exchanger. The standard procedure was complemented with some additional elution systems which made it feasible to separate in the extract and to analyse, in addition to the conventional mono-, di- and triphosphates, UDP-glucose, UDP-N-acetylglucosamine, CDP-choline and CDP-ethanolamine. The two different purine nucleotides (A, G) and the two different pyrimidine nucleotides (U, C) exhibited normal ratios (energy charge ratios) between the conventional nucleotides. This would indicate that the erythrocytes have a sufficient energy production. It is suggested that the partly intravascular hemolysis might be due to disturbed synthesis of phospholipids.

Purine metabolism in normal and ITP-pyrophosphohydrolase-deficient human erythrocytes.

Fresh and stored erythrocytes from normal and ITP-pyrophosphohydrolase (ITP-ase, EC 3.6.1.19) deficient individuals were incubated with hypoxanthine, guanine, allopurinol, and inosine. Differences in the purine metabolism between the normal and the ITP-ase deficient erythrocytes were observed only in the IMP-ITP cycle. Hypoxanthine, guanine and allopurinol were converted to nucleotides at the same rate. Hypoxanthine (2.5 mumol/l) inhibited the salvage of allopurinol (40 mumol/l). A slow decrease (0.7%/day) in salvage rate was observed in both types of cells upon storage at +4 degrees C. Erythrocyte ITP-ase activity was measured in a reference sample group of 48 healthy volunteers. Two distinct groups were found with mean activities equal to 48.3 +/- 13.1 nkat/g Hb (means +/- SD, n = 38) and 11.4 +/- 4.3 nkat/g Hb (n = 10). In two previously selected subjects, the ITP-ase activity was 0.2 and 2.4 nkat/g Hb. A hypothetical genetic mechanism is discussed. The maximal energy turnover in the IMP-ITP cycle during hypoxanthine incubation was found to be less than 10% of the basal erythrocyte energy turnover.

High adenosine content in human uterine smooth muscle compared with striated skeletal muscle.

We determined the concentrations of adenosine and some of its catabolic products in biopsy specimens from predetermined loci of human myometrium under different functional conditions to compare uterine muscle with rectus abdominis muscle from the same individuals. In order to achieve a good resolution in the separation of nucleosides and purine bases, a preseparation procedure was developed prior to analysis of these compounds on high performance liquid chromatography. Adenosine occurred in a nearly 70-fold higher concentration in smooth uterine muscle in comparison with striated skeletal muscle. Similarly, myometrial inosine and hypoxanthine were 7- and 2.4-times in excess over the rectus muscle, whereas xanthine was scarcely and rather evenly represented in the two types of muscles. The uterine content of adenosine and inosine was distinctly higher in pregnant women compared to non-pregnant ones. A regional difference existed for adenosine, with 3.3 times higher concentration in fundus uteri compared to the isthmic part. A reverse pattern was observed for hypoxanthine and inosine, being 2-3 times more frequent in the isthmic part. The orthophosphate concentration was not stoichiometrically related to the adenosine concentration in a simple way, being 2-3 times lower in uterine muscle compared to the skeletal muscle. A significant correlation existed between uterine contents of AMP and adenosine and similarly, significant inverse correlations were apparent between uterine ATP and ADP contents and energy charge on one hand and adenosine content on the other.

Incidence of legal abortion in Sweden after the Chernobyl accident.

The number of legal abortions in Sweden increased around the time of the Chernobyl accident, particularly in the summer and autumn of 1986. Although there was no recording of reasons for legal abortions, one might have suspected this increase to be a result of fear and anxiety after the accident. However, seen over a longer time perspective, the increase in the number of abortions started before and continued far beyond the time of the accident. There was also a simultaneous and pronounced increase in the number of births during the years subsequent to the accident. Therefore, it seems unlikely that fear of the consequences of radioactive fall-out after the Chernobyl accident resulted in any substantial increase of the number of legal abortions in Sweden.

PIP: After the Chernobyl accident, there was concern about the effects of the accident on pregnancy in Sweden. This concern is addressed by analyzing the trends in legal abortion and births between 1960. Although abortion has been legal since 1975, there is no requirement to report the reason, only the incidence to the National Board of Health on a monthly basis. In 1986 legal abortions totaled 33,124, which was an increase over preceding years. The increase continued up to 1990. July 1986 marked an increase particularly among women 15-25 years, but this increase also appeared in July 1988 and 1989. If Chernobyl was the cause, one would expect a decrease in births, which in fact did not occur. There has been an increase in births and a shift toward higher maternal age. This suggests that younger women are using abortion as birth control. 1986 coincidentally marked a period of change in reproductive behavior. If chernobyl had an effect, then it is expected that it would be short term for abortions and births, with an increase in abortion and a decrease in births; instead, there is a 4-year trend in increased abortions and births. The results of the National Board of Health's inquiry into area-specific rates and reported radioactive fallout for each area showed no differences in trends in abortion rates between areas. This also suggests little influence of Chernobyl on abortion rates. Few studies are available that explore the reasons for pregnancy termination and none were conducted after Chernobyl. In a 1982 Stockholm study, over 50% reported unstable or nonexistent relationships with the father, another 25% reported socioeconomic reasons, and the remainder reported too young age as a reason. It is concluded that there is little evidence to support the position that the Chernobyl accident caused pregnancy termination out of fear and anxiety among Swedish women, even though women in antenatal clinics did express concern about the accident's consequences.