Leaky gut biomarkers in depression and suicidal behavior.

OBJECTIVE: Inflammation is associated with major depressive disorder (MDD) and suicidal behavior. According to the 'leaky gut hypothesis', increased intestinal permeability may contribute to this relationship via bacterial translocation across enterocytes. We measured plasma levels of gut permeability markers, in patients with a recent suicide attempt (rSA), MDD subjects with no history of a suicide attempt (nsMDD), and healthy controls (HC), and related these markers to symptom severity and inflammation. METHOD: We enrolled rSA (n = 54), nsMDD (n = 13), and HC (n = 17). Zonulin, intestinal fatty acid binding protein (I-FABP), soluble CD14, and interleukin-6 (IL-6) were quantified in plasma. Montgomery-Åsberg Depression Rating Scale (MADRS) and Suicide Assessment Scale (SUAS) were used for symptom assessments. RESULTS: The rSA group displayed higher I-FABP and lower zonulin levels compared with both the nsMDD and the HC groups (all P < 0.001). IL-6 correlated positively with I-FABP (r = 0.24, P < 0.05) and negatively with zonulin (r = -0.25, P < 0.05). In all subjects, I-FABP levels correlated positively with MADRS (r = 0.25, P < 0.05) and SUAS scores (r = 0.38, P < 0.001), and the latter correlation was significant also in the nsMDD group (r = 0.60, P < 0.05). CONCLUSION: The 'leaky gut hypothesis' may improve our understanding of the link between inflammation and suicidal behavior. These findings should be considered preliminary until replicated in larger cohorts.

Glucose-lowering effect of the DPP-4 inhibitor sitagliptin after glucose and non-glucose macronutrient ingestion in non-diabetic subjects.

AIM: Recent studies suggest that the incretin concept is not restricted to glucose ingestion but relevant also after non-glucose macronutrient administration. We therefore hypothesized that raising incretin hormones reduces circulating glucose after both glucose and non-glucose macronutrient ingestion in healthy subjects. METHODS: Twelve healthy subjects received the dipeptidyl peptidase-4 inhibitor sitagliptin (100 mg) or placebo before ingestion of glucose, fat (olive oil) or protein mix in equicaloric amounts (8 kcal/kg) plus paracetamol (1.5 g). The 120-min areas under curve (AUC) of intact glucagon-like peptide-1 (GLP-1), glucose, insulin, C-peptide, glucagon and paracetamol, and model-derived insulin secretion rate (ISR), insulin sensitivity, insulin clearance and glucose absorption were measured. RESULTS: The increased plasma intact GLP-1 levels after each macronutrient was augmented by sitagliptin. This was associated with a robust lowering of glucose: glucose excursion after oral glucose was diminished, and glucose fell below baseline after oral fat and protein. In spite of lower glucose, AUCC -peptide and ISR did not differ significantly between sitagliptin and placebo after any macronutrient. AUCglucagon , insulin sensitivity and insulin clearance were also not different between sitagliptin and placebo. Glucose absorption after oral glucose was reduced by sitagliptin, whereas AUCparacetamol was not statistically different between sitagliptin and placebo. CONCLUSIONS: Physiological elevation of intact GLP-1 levels after ingestion of glucose and non-glucose macronutrients is robustly glucose-lowering in healthy subjects. Hence, the incretin concept is not restricted to glucose ingestion in normal physiology. The glucose-lowering action of sitagliptin at these low glucose levels in healthy subjects may have complex mechanisms, involving both islet-dependent and islet-independent mechanisms.

Lymph node tissue kallikrein-related peptidase 6 mRNA: a progression marker for colorectal cancer.

BACKGROUND: A most important characteristic feature for poor prognosis in colorectal cancer (CRC) is the presence of lymph node metastasis. Determination of carcinoembryonic antigen (CEA) mRNA levels in lymph nodes has proven powerful for quantification of disseminated tumour cells. Here, we investigate the utility of human tissue kallikrein-related peptidase 6 (KLK6) mRNA as a progression biomarker to complement CEA mRNA, for improved selection of patients in need of adjuvant therapy and intensified follow-up after surgery. METHODS: Lymph nodes of pTNM stage I-IV CRC- (166 patients/503 lymph nodes) and control (23/108) patients were collected at surgery and analysed by quantitative RT-PCR. RESULTS: Lymph node KLK6 positivity was an indicator of poor outcome (hazard ratio 3.7). Risk of recurrence and cancer death increased with KLK6 lymph node levels. Patients with KLK6 lymph node levels above the 90th percentile had a hazard ratio of 6.5 and 76 months shorter average survival time compared to patients with KLK6 negative nodes. The KLK6 positivity in lymph nodes with few tumour cells, that is, low CEA mRNA levels, also indicated poor prognosis (hazard ratio 2.8). CONCLUSION: In CRC patients, lymph node KLK6 positivity indicated presence of aggressive tumour cells associated with poor prognosis and high risk of tumour recurrence.

Increased plasma levels of circulating cell-free mitochondrial DNA in suicide attempters: associations with HPA-axis hyperactivity.

Preclinical data suggest that chronic stress may cause cellular damage and mitochondrial dysfunction, potentially leading to the release of mitochondrial DNA (mtDNA) into the bloodstream. Major depressive disorder has been associated with an increased amount of mtDNA in leukocytes from saliva samples and blood; however, no previous studies have measured plasma levels of free-circulating mtDNA in a clinical psychiatric sample. In this study, free circulating mtDNA was quantified in plasma samples from 37 suicide attempters, who had undergone a dexamethasone suppression test (DST), and 37 healthy controls. We hypothesized that free circulating mtDNA would be elevated in the suicide attempters and would be associated with hypothalamic-pituitary-adrenal (HPA)-axis hyperactivity. Suicide attempters had significantly higher plasma levels of free-circulating mtDNA compared with healthy controls at different time points (pre- and post-DST; all P-values<2.98E-12, Cohen's d ranging from 2.55 to 4.01). Pre-DST plasma levels of mtDNA were positively correlated with post-DST cortisol levels (rho=0.49, P<0.003). Suicide attempters may have elevated plasma levels of free-circulating mtDNA, which are related to impaired HPA-axis negative feedback. This peripheral index is consistent with an increased cellular or mitochondrial damage. The specific cells and tissues contributing to plasma levels of free-circulating mtDNA are not known, as is the specificity of this finding for suicide attempters. Future studies are needed in order to better understand the relevance of increased free-circulating mtDNA in relation to the pathophysiology underlying suicidal behavior and depression.

Acute and long-term biphasic volume alterations in rat type-II somatotrophs during GH secretory stimulation.

The size and shape of growth hormone (GH)-producing rat (type II)-somatotrophs was studied during secretory stimulation by either human GH-releasing hormone (hGHRH(1-29)) or 50 nM extracellular potassium. A new type of perfusion chamber for light microscopy allowed the interpretation of early changes in cell morphology. The exposure to 10 nM hGHRH caused a significant transient decrease in cell volume to 94.4 +/- 2.1% within 2 s. The cell volume recovered to 99.2 +/- 1.3% at 30 s. A second, more gradual volume decrease then followed (60 s), which stabilized at about 92.5 (8 min) and was still present after 20 min of continuous hGHRH exposure. Potassium, 50 mM, gave an immediate and persistent cell volume increase of about 5%. The fluctuation in rat somatotroph volume after hGHRH exposure correlates to a previously observed biphasic GH-secretory pattern involving an initial burst secretion and a second slow phase secretion. The transient early volume decrease may reflect ion fluxes across the membrane and/or the response of the cytoskeleton to calcium mobilization during the GH-secretory onset. The second, persistent, volume decrease closely correlates to the calculated volume of lost GH vesicles.

The correlation between calcium outflow and growth hormone release in perifused rat somatotrophs.

The time-relationships between GH secretion and 45Ca2+ efflux in response to human GRF (hGRF)-(1-29), hGRF-(1-44), 3-isobutyl-1-methylxanthine (IBMX), (Bu)2-cAMP, and high extracellular K+ were studied in perifused cultured rat somatotrophs. In cells exposed to 1-10 nM hGRF-(1-29) or -(1-44), GH release and 45Ca2+ efflux increased during the first 15 sec and reached peak values within 75 sec. At lower GRF concentrations, 45Ca2+ efflux still increased within 15 sec while GH secretion commenced 15-30 sec later. hGRF-(1-29) increased GH release and 45Ca2+ efflux also after 30 min preperifusion in a calcium-depleted medium with 0.1 mM EGTA added during the last 5 min of preperifusion. However, the magnitude of the stimulation was lower than in the presence of calcium. IBMX increased GH release and 45Ca2+ efflux within 15 sec and peak values were reached within 60 sec. (Bu)2cAMP increased GH release both in the presence and absence of extracellular calcium although the magnitude of stimulation was less in the calcium-depleted medium. Efflux of 45Ca2+ was stimulated by (Bu)2cAMP, independently of extracellular calcium. When exposed to 50 mM K+, both GH release and 45Ca2+ efflux increased within 15 sec and reached high peak values within 60 sec, an effect blocked by removal of extracellular calcium. We conclude that GRF and three other GH secretagogues, (Bu)2cAMP, IBMX, and a high extracellular K+ concentration, rapidly increase 45Ca2+ efflux. GH release and 45Ca2+ efflux appear to be tightly coupled with the calcium response perhaps slightly preceding GH release. This tight coupling strengthens the hypothesis that increased Ca2+ activity is directly involved in exocytosis. GRF and (Bu)2cAMP stimulate GH release and 45Ca2+ efflux also in a calcium-free medium, suggesting that mobilization of intracellular calcium is involved in the action of these secretagogues.

Effect of N-methyl-D,L-aspartate on isolated rat somatotrophs.

The effect of excitatory amino acid receptor agonists on GH secretion was tested in isolated male rat somatotrophs. N-Methyl-D,L-Aspartate (NMDA) had a dose-dependent stimulatory effect on GH secretion in perifused somatotrophs. The effect was observed already during the first minute after exposure to NMDA and was reversible after its omission. The effect of 1 microM NMDA was inhibited by the NMDA receptor antagonists 10 microM AP7 and 5 microM MK801, and by 5 microM dextromethorphan. L-Glutamate, 100 microM, and 100 microM kainic acid also stimulated GH secretion. The stimulatory effect of NMDA on GH release was paralleled by an increase in 45Ca efflux and an increase in somatotroph intracellular calcium concentration. Efflux of 86Rb (tracer for potassium) was not affected by NMDA. It is concluded that excitatory amino acids can stimulate GH secretion in rats through a direct effect on the somatotrophs.

Effects of 5-hydroxytryptamine, dopamine, and aromatic L-amino acids on growth hormone (GH)-releasing factor-stimulated GH release in rat anterior pituitaries.

The importance of monoaminergic mechanisms for the regulation of GH-releasing factor (GRF)-stimulated GH secretion was studied in perifused rat anterior pituitaries. Dopamine (greater than 1 microL) reduced GRF-stimulated GH release, but 5-hydroxytryptamine (5-HT; 1 mL) had no effect. The substrates for L-aromatic amino acid decarboxylase, L-5-hydroxy-tryptophan(L-5-HTP; 10 microM) L-dihydroxyphenylalanine; (1 mM), D,L-o-tyrosine (2 mM), and D,L-m-tyrosine (2 mM), all reduced GRF-stimulated GH release. Inhibition of the L-aromatic amino acid decarboxylase by benserazide (0.1 mM), carbidopa (0.1 mM), or alpha-monofluoromethyldopa (0.1 mM) did not reduce the effect of the decarboxylase substrates on GH secretion. The enzyme inhibitors had no influence on hormone secretion per se. The findings indicate that dopamine may inhibit GRF-induced GH release at the pituitary level and that the precursor amino acids inhibit GH secretion independently of the formation of the corresponding amines.

Islet cell antibodies, but not glutamic acid decarboxylase antibodies, are decreased by plasmapheresis in patients with newly diagnosed insulin-dependent diabetes mellitus.

The effects of plasmapheresis on islet autoantibody levels, C-peptide (beta-cell function), and hemoglobin-A1c (HbA1c, metabolic control) were tested in a prospective blinded study of 18 newly diagnosed insulin-dependent diabetes mellitus (IDDM) patients randomly assigned to receive plasmapheresis (P), carried out as double filtration, or sham (S) treatment at diagnosis and 3 months thereafter. At diagnosis, 6 of 8 patients (75%) in group P and 9 of 10 patients (90%) in group S had islet cell antibodies (ICA), whereas 4 of 8 (50%) and 7 of 10 (70%) patients, respectively, had glutamic acid decarboxylase antibodies (GAD65-Ab), with no significant differences between the groups in ICA and GAD65-Ab levels. After 6 months, P patients showed significantly lower ICA levels than S patients (11 +/- 6 and 128 +/- 47 Juvenile Diabetes Foundation International Units, respectively; P < 0.02) due to an increase in ICA levels in 8 of 9 (88%) of the S patients not seen in P patients (P < 0.002). Concurrently, HbA1c stabilized in P, but not in S, patients and was significantly lower by 24 months (6.58 +/- 0.54% vs. 9.76 +/- 1.21%; P < 0.05). Moreover, fasting C-peptide increased significantly (214 +/- 11 pmol/L; P < 0.05) over the first 6 months in P. After the initial 6 months, ICA levels tended to decrease in all patients and were not detected after 60 months. GAD65-Ab levels were not influenced by plasmapheresis and, also in contrast to ICA, increased significantly (P < 0.05) in the whole study population after 60 months. In fact, 4 initially negative patients became GAD65-Ab positive after diagnosis (in 2 patients > 24 months after diagnosis). We conclude that plasmapheresis of newly diagnosed IDDM patients does not change subsequent GAD65-Ab levels, but ICA are significantly decreased with associated improved C-peptide and HbA1c levels.

Metamorphosis of identified neurons innervating thoracic neurohemal organs in the blowfly: transformation of cholecystokininlike immunoreactive neurons.

With antisera to gastrin/cholecystokinin, we studied the postembryonic development of neurons in the thoracic ganglia of the blowfly Calliphora erythrocephala. There are some changes in the population of thoracico-abdominal neurons displaying gastrin/CCK-like immunoreactivity (CCKLI): some CCKLI neurons cannot be found after pupariation; other neurons become immunoreactive during metamorphosis. Six large thoracic CCKLI neurons could, however, be followed through metamorphosis. These CCKLI neurons innervate neuropil in thoracic ganglia and segmental neurohemal organs in the larva. In the adult insect the same neurons innervate many regions of thoracic neuropil and extensive neurohemal areas dorsally in the fused thoracico-abdominal ganglia. The immunoreactive terminals are located in the neural sheath, and electron microscopy shows that only an extracellular basal lamina separates them from the circulating hemolymph. On the basis of the location of their terminals, it can be suggested that the six CCKLI neurons have functions as neurosecretory cells both in the larva and in the adult. In both developmental stages the neurons can interact with large portions of the thoracic nervous system and release bioactive substance into the circulation. A CCK-like substance may be used both as a transmitter/neuromodulator and as a neurohormone by the same neuron. The larval neurohemal organs are described here for the first time. They show characteristics of thoracic perisympathetic organs known to exist in more primitive insects. The adult neurohemal regions on the other hand are typical of higher insects. Since the neurohemal areas are continuously (during development) innervated by the six large CCKLI neurons, we conclude that the larval neurohemal organs metamorphose into the adult neurohemal area in the neural sheath.

Postembryonic differentiation of serotonin-immunoreactive neurons in fleshfly optic lobes developing in situ or cultured in vivo without eye discs.

The differentiation of serotonin-immunoreactive (5-HTi) neurons in the optic lobes of fleshflies was studied during in situ development and in in vivo cultures. All 5-HTi neurons with cell bodies in the imaginal optic lobes differentiate during postembryonic (pupal) development. These are local anaxonal neurons. In addition there are two large 5-HTi bilateral neurons that connect all optic lobe neuropil regions on both sides of the brain and have their cell bodies in the midbrain proper. Deafferentation of optic lobes cultured in vivo leads to drastic reduction in optic lobe volume and increased cell death. All the 5-HTi neurons differentiate after deafferentation but their morphology changes. The neuropil receiving the photoreceptor inputs, the lamina, degenerates but a disorganized "pseudolamina" is formed by the processes of the two large 5-HTi neurons. The layering of the optic lobe neuropils cannot be distinguished and 5-HTi processes form novel projectional patterns. Hence, the 5-HTi neurons do not require afferent inputs from the retina for their differentiation and survival, but the effect on other optic lobe interneurons is reflected in the morphological plasticity of the 5-HTi neurons.

Acute antithrombotic effects of ximelagatran, an oral direct thrombin inhibitor, and r-hirudin in a human ex vivo model of arterial thrombosis.

BACKGROUND: Thrombin plays a major role in thrombus formation through activation of platelets and conversion of fibrinogen to fibrin. OBJECTIVES: To investigate the antithrombotic effects of the oral direct thrombin inhibitor (DTI) ximelagatran and the parenteral DTI r-hirudin in humans. SUBJECTS AND METHODS: Healthy male volunteers randomized into four parallel groups each with 15 subjects received either ximelagatran (20, 40 or 80 mg orally) or r-hirudin (0.4 mg kg-1 intravenous bolus + infusion of 0.15 mg kg-1 h-1 for 2 h and 0.075 mg kg-1 h-1 for 3 h). Antithrombotic effects were assessed as changes in total thrombus area (TTA) and total fibrin area (TFA) from baseline, using the Badimon perfusion chamber model at baseline and 2 h and 5 h after drug administration. RESULTS: Two hours postdosing, ximelagatran showed antithrombotic effects at both high and low shear rates (TTA% of mean baseline value +/- SEM was 76 +/- 13% and 71 +/- 17% [both P < 0.05] for the 20-mg dose, 85 +/- 11% [P > 0.05] and 62 +/- 15% [P < 0.05] for the 40-mg dose and 60 +/- 11% and 26 +/- 7% [both P < 0.05] for the 80-mg dose, respectively). r-Hirudin also showed a significant antithrombotic effect at high and low shear rates (76 +/- 11% [P = 0.05] and 57 +/- 17% [P < 0.05] of baseline values, 2 h postdosing, respectively). The inhibitory effects on TFA were similar to those on TTA. CONCLUSIONS: The oral DTI ximelagatran shows antithrombotic effects under both high and low shear conditions. The antithrombotic effect of 40-80 mg ximelagatran appeared comparable to that of parenterally administered r-hirudin, which has been previously demonstrated to be clinically effective in acute coronary syndromes.

Cancer pain relief by continuous administration of epidural morphine in a hospital setting and at home.

Fifteen patients with severe pain due to malignancy were treated by continuous epidural morphine infusions. A disposable external pump was used. Patients were treated in a hospital setting or at home for a total of 906 days. Pain intensity was estimated by VAS. The pumps functioned well. Bacterial growth was found in 0.6% of the balloon reservoirs used, while the epidural filters were free from growth. There were no clinical infections. It appears that this delivery system is safe, practical and suitable for use in the home environment.

Light and electron microscopic immunocytochemistry of neurons in the blowfly optic lobe reacting with antisera to RFamide and FMRFamide.

Different antisera to the molluscan cardioexcitatory peptide FMRFamide, and its fragment, RFamide (Arg-Phe-NH2), label a distinct population of neurons in the optic lobe of the blowfly, Calliphora erythrocephala. Seven morphological types of RFamide/FMRFamide-like immunoreactive neurons could be distinguished in the optic lobes based on the locations of their cell bodies, their axonal projections and the distribution of their processes. Of these, two types could be resolved in their entire extent, the others were labeled only in their cell bodies and terminal processes or were partly obscured by other immunoreactive processes. The RF-like immunoreactive neurons in the optic lobes are of two main classes: (1) two types of large field projection neurons and (2) five types of local neurons. One type of projection neurons (five in each lobe) connects the entire projected retinal mosaic of the medulla and lobula in the optic lobe with protocerebral centres associated with the mushroom body calyx. The other type (2-3 invading each lobe) has cell bodies in the protocerebrum and contralateral processes invading optic lobes. Of the class of local neurons there are two amacrine RF-like immunoreactive neurons in each medulla. Each of these amacrines supplies the entire mosaic with fine processes. The remaining local RF-like immunoreactive neurons are present in relatively large numbers (one type in more than 2000 copies in each medulla) and-supply the medulla, lobula and lobula plate neuropils with fine varicose processes. In the medulla the RF-like immunoreactive processes are arranged in strict layers whereas in the lobula complex the distribution is diffuse. Electron microscopic immunocytochemistry, using both pre-embedding immuno peroxidase-antiperoxidase and post-embedding protein A-gold labeling, was employed for analysis of cytology and synaptic connections of RF-like immunoreactive neurons in the medulla. The varicosities of the processes of the large field projection neurons were not found to make chemical synapses with other neurons in the medulla. The spines of the RF-like immunoreactive processes of the large medulla amacrines, however, make pre- and postsynaptic contacts with other neural elements. Our findings indicate that an RFamide/FMRFamide-like substance may be used as a neurotransmitter or neuromodulator by optic lobe neurons of different types. The local and projection RF-like immunoreactive pathways probably play different roles in visual processing.

Endogenous testosterone enhances growth hormone (GH)-releasing factor-induced GH secretion in vitro.

The influence of endogenous gonadal steroids in male and female rats on basal and growth hormone-releasing factor (GRF)-stimulated GH secretion from perifused anterior pituitaries was studied. After 75 min of perifusion with basal medium, freshly dissected pituitaries were exposed to human GRF(1-44) (10 nmol/l) for 15 min. Neonatal (day 1-2) or prepubertal (day 25) gonadectomy of male rats suppressed baseline GH release (ng/min per mg dry weight) as well as GRF-stimulated GH release by 40-70%. This effect was slightly more pronounced in neonatally gonadectomized animals. In prepubertally gonadectomized male rats, the suppression of GH release was completely reversed by testosterone replacement therapy. In female rats, prepubertal gonadectomy did not affect GH secretion from perfused pituitaries. However, treatment of ovariectomized female rats with oestradiol reduced baseline and GRF-induced GH release to levels lower than those observed in sham-operated or vehicle-treated ovariectomized animals. The data suggest that testicular androgen secretion in adult male rats increases the pituitary GH release in response to GRF in vitro, whereas ovarian oestrogen secretion is of less importance for the GRF responsiveness of female rat pituitaries.

An ultrastructural and functional characterization of rat somatotrophs highly enriched on a continuous Percoll density gradient.

We here describe the use of a continuous Percoll density gradient in preparing a fraction of consistently more than 95% rat somatotrophs. Recovery was about 50% and cell viability 98-99.5%. Two groups of somatotrophs were identified, one (74-82%, type II) heavily and another (18-26%, type I) sparsely granulated. Freshly prepared somatotrophs responded to growth hormone-releasing factor but the responsiveness was greatly enhanced after 3 days' culture. Electron microscopy revealed a well-preserved morphological integrity in both freshly prepared and cultured somatotrophs. culture reduced the average granule profile area and granule volume density of type II cells. This population of pure and well-functioning somatotrophs is suited for studies on the cellular mechanisms involved in growth hormone secretion.

Treatment with tumor-reactive Fab-IL-2 and Fab-staphylococcal enterotoxin A fusion proteins leads to sustained T cell activation, and long-term survival of mice with established tumors.

C215Fab-IL-2 fusion protein, with full IL-2 and antigen binding activity, was produced in E. coli at high level (>50 mg/l). When co-administered with Fab-superantigen fusion protein (C215Fab-SEA) in mice strong and sustained T cell activation was observed. Combination treatment of mice carrying B16 melanoma transfected with C215 antigen was also more efficient than using C215Fab-SEA (p<0.01) or C215Fab-IL-2 alone (p<0.001). In a long-term survival experiment 5/12 mice having received combination treatment 5 days after i.v. inoculation of B16 cells survived >85 days. Improved therapeutic efficacy correlated with increased tumor infiltration by activated CD25+ T cells, indicating a T cell mediated mechanism.

Non-palpable inguinal hernia in the female.

A total of 142 inguinal hernioplasties in 130 female patients with nonpalpable inguinal hernias were performed over a period of 8 years. The mean age in this series was 32 years. (Range 10-76 years). One hundred thirty six cases were followed 3-51 months postoperatively. One hundred seventeen of these (86%) were considered to have good results. Nonpalpable inguinal hernia in the female is clinically recognizable on the basis of intermittency, character and localization of the pain and typical findings at the clinical examination. About three quarters of these patients report in addition to dull inguinal pain, intermittent neuralgic pain and in almost two thirds of the patients a pin-prick hyperalgesia of the skin corresponding to the ilio-inguinal nerve can be demonstrated. It is also typical that all patients experience a distinct tenderness upon palpation over the deep inguinal ring during Valsalva's maneuvre. It is important to keep this condition in mind, especially since the patients respond well to surgical treatment.

Evidence for specific ceramidase present in the intestinal contents of rats and humans.

A neutral ceramidase activity stimulated by bile salt was previously identified in the intestinal content. Recently, bile salt stimulated lipase (BSSL) was found to have ceramidase activity. It is unknown whether the ceramidase activity previously found is attributable to BSSL. To address this question, we compared the behaviors of high quaternary aminoethyl (HQ) anion exchange chromatography, the distributions, the stability, and the responses to lipase inhibitor between ceramidase and pancreatic BSSL. The proteins from whole small intestinal contents of humans and rats were precipitated by acetone and dissolved in 20 mM Tris buffer pH 8.2. These proteins had neutral ceramidase activity but not BSSL activity against p-nitrophenyl acetate. When the proteins were subject to HQ chromatography, two peaks of ceramidase activity were identified, which had acid and neutral pH optima, respectively. Neither of them had BSSL activity against p-nitrophenyl acetate. Western blot using BSSL antiserum failed to identify BSSL protein in the fractions with high neutral ceramidase activity. In rat intestinal tract, pancreatic BSSL activity was high in the duodenum and declined rapidly in the small intestine, whereas neutral ceramidase activity was low in the duodenum and maintained a high level until the distal part of the small intestine. In addition, orlistat, the inhibitor of lipase, abolished human BSSL activity against p-nitrophenyl acetate and slightly reduced its activity against ceramide but had no inhibitory effect on ceramidase activity isolated by HQ chromatography. In conclusion, we provide the evidence for a specific ceramidase other than pancreatic BSSL present in the intestinal content. The enzyme may play important roles in digestion of dietary sphingolipids.

Outcomes of periradicular surgery in cases with apical pathosis and untreated canals.

OBJECTIVE: Surgical management is intended to eliminate or block infection originating in the root canals. The root end is customarily sealed to prevent pathogenic products remaining in the root canal from reaching the periradicular tissues. The purpose of this study was to evaluate the microbiologic and radiographic outcomes of surgical treatment of periradicular pathosis associated with teeth with necrotic pulps. STUDY DESIGN: One tooth from each of 10 patients was root-end resected and root-end filled without prior root canal treatment. One year postoperatively, the outcomes were assessed radiographically and the root canals were sampled for bacteria. RESULTS: Radiographic examination showed complete or incomplete (scar tissue) healing in 5 teeth and uncertain healing in the other 5 teeth. Bacteriologic samples from the root canals were positive in 9 of the 10 cases. CONCLUSIONS: In teeth with necrotic pulps, treatment of periradicular pathosis by surgery and root-end filling may show radiographic evidence of satisfactory healing 1 year postoperatively. However, viable bacteria may persist in the canals, constituting a potential risk factor for recurrence of periradicular pathosis.