Hydrological, thermal and chemical influence of an intact rock glacier discharge on mountain stream water

Rock glaciers are the most prominent permafrost-related mountain landforms. This study investigates the effects of the discharge from an intact rock glacier on the hydrological, thermal and chemical dynamics of a high-elevation stream in the NW Italian Alps. Despite draining only 39 % of the watershed area, the rock glacier sourced a disproportionately large amount of discharge to the stream, with the highest relative contribution to the catchment streamflow occurring in late summer - early autumn (up to 63 %). However, ice melt was estimated to be only a minor component to the discharge of the rock glacier, due to its insulating coarse debris mantle. The sedimentological characteristics and internal hydrological system of the rock glacier played a major role in its capability to store and transmit relevant amounts of groundwater, especially during the baseflow periods. Besides the hydrological influence, the cold and solute-enriched discharge from the rock glacier significantly lowered the stream water temperature (especially during warm atmospheric periods) as well as increased the concentrations of most solutes in the stream. Furthermore, in the two lobes forming the rock glacier, different internal hydrological systems and flowpaths, likely driven by different permafrost and ice content, caused contrasting hydrological and chemical behaviours. Indeed, higher hydrological contributions and significant seasonal trends in solute concentrations were found in the lobe with higher permafrost and ice content. Our results highlight the relevance of rock glaciers as water resources, despite the minor ice melt contribution, also suggesting their potential, increasing hydrological importance in the light of climate warming.

Role of landslides on the volume balance of the Nepal 2015 earthquake sequence

The 7.8 M_w earthquake that struck Nepal on April 25th, 2015 triggered over 21,000 landslides over an area of more than 25,000 km². These landslides contributed to mass wasting, partially compensating the tectonic uplift by the earthquake. In this paper we quantify the volume balance resulting from the 2015 earthquake uplift (or subsidence) and landslide erosion. Starting from a new complete earthquake-induced landslide inventory, we calculated landslide volume by adopting different strategies for low-mobility and high-mobility landslides, considering also the potential supply of sediments to the drainage network. The results show that the contribution of earthquake-induced landslides to erosion is about one order of magnitude smaller than the vertical coseismic displacement. We found landslide volume values, due to the 2015 Nepal earthquake, ranging between 251 (- 15/ + 16) Mm³ up to 1503 (- 183/ + 210) Mm³ based on the adopted method, and a volume due to coseismic vertical displacement of 2134 (± 1269) Mm³ for the whole area. The volume balance of the 2015 Nepal earthquake is strongly dominated by tectonic displacement. We show that these estimates depend on several uncertainties. We identified and quantified uncertainties related to: (1) the choice of empirical volume-area scaling relationships and their parameters; (2) the completeness and quality of landslide inventory through comparison with available inventories; (3) the approach adopted for the assessment of elongated landslide volume; (4) the InSAR displacement data.

Intestinal perforation secondary to blunt abdominal trauma in pre-existing inguinal hernia

Inguinal hernias are very common in men. We report a rare case of intestinal perforation following blunt abdominal trauma in a 80-year-old man with pre-existing inguinal hernia. A careful and serial physical examination, with the information obtained from the computed tomography (CT) scan guides the prompt surgical exploration. This case demonstrates that external forces, that may seem too trivial to cause intraperitoneal injury, can cause significant injury when applied to a patient with a hernia. It is possible to repair the intestinal perforation and inguinal hernia in the same operation.

Effect of acute alcohol on ischemia-induced glutamate release and brain damage

Epidemiological studies show that chronic ethanol consumption at high doses enhances the risk of cerebral stroke. The mechanisms responsible for the greater vulnerability of alcoholics' brains to stroke have to be completely understood, but a role for excitatory amino acids has been suggested. In order to study the interaction between alcohol and ischemia, we investigated the effect of acute alcohol administration in a model of focal cerebral ischemia. In particular, we evaluated the release of glutamate and aspartate from the cerebral frontal cortex by a transdialysis technique. Alcohol was acutely administered at 1.5 and 3.0 g/kg ip. During the period of maximal alcoholemia, ethanol almost abolished the ischemia-induced release of glutamate leading to glutamate values around or below the basal. Aspartate levels were unaltered both following ischemia and alcohol+ischemia. The decrease in glutamate release, however, was not accompanied by a significant reduction of the extension of the damaged area assessed by histological analysis.

Higher plasma catecholamine and metabolite levels in the early phase of nonsegmental vitiligo

The etiology of vitiligo is still being debated, although neural factors seem to play a pivotal role in its pathogenesis. In our search for a link between vitiligo and the activity of monoaminergic systems, we used high-pressure liquid chromatography and electrochemical detector (HPLC-ED) methods to measure the plasma levels of the following substances in 35 healthy subjects and in 70 patients suffering from nonsegmental vitiligo at the different stages of the disease: catecholamines [norepinephrine (NE), epinephrine (E), and dopamine (DA)], their precursor 3,4-dihydroxyphenylalanine (DOPA), their metabolites [3-methoxy-4-hydroxyphenylglycol (MHPG), normetanephrine (NMN), metanephrine (MN), and homovanillic acid (HVA)], and 5-hydroxyindolacetic acid (5-HIAA) as the major metabolite of serotonin. We found that the levels of NE, E, NMN, MN, HVA, and 5-HIAA were significantly higher in patients compared to controls. The patients at an active phase of the disease (n = 49/70) showed significantly higher levels of NE, NMN, MHPG, and HVA than ones at a stable phase. The patients with progressive vitiligo and at its more recent onset (< 1 year) showed significantly increased levels of E, NE, and MN in comparison with longer-term sufferers. No significant differences were observed when the patients were subdivided according to the type of vitiligo or their age at its onset. The higher catecholamine and metabolite levels in the early phase of the disease may reflect increased activity by monoaminergic systems, probably due to stressful events, including the onset of vitiligo itself.

Liver ischemia modifies the concentration of plasmatic catecholamines after reperfusion in the rat

Pulmonary hypertension is one of the most frequent and severe consequences of liver ischemia. The aim of this study is to evaluate the presence of humoral vasoactive mediators, generated during liver ischemia, which could be able to determine the onset of pulmonary hypertension. Thus, we evaluated the plasmatic concentration of catecholamines (adrenaline, noradrenaline, dopamine) during the immediate reperfusion period. Wistar rats were used. Animals (n = 89) were divided into four groups. Group 1 served as control (sham-operated). In group 2 animals underwent 60 min of left hepatic exclusion. In group 3 animals underwent to bilateral adrenectomy. In group 4 animals had both bilateral adrenectomy and liver ischemia. Ischemia in group 2 and 4 was induced by interrupting the vascular supply to the left and median lobes, so avoiding the use of a portal shunt. Blood samples were collected from the suprahepatic inferior caval vein immediately after reperfusion. Strips of the main pulmonary artery were put into an isolated organ bath and tested for the response to noradrenaline, adrenaline and plasma samples. Plasma samples collected after ischemia caused a significantly greater (p < 0.01) contraction of the pulmonary artery compared to controls. Plasma samples collected after adrenectomy caused a weak contraction which was not different from that obtained in the adrenectomy + ischemia group. Plasma concentrations of catecholamines after liver ischemia were significantly increased in the control group (p < 0. 01). In adrenectomized rats only the adrenaline level was greatly reduced. However ischemia did not increase plasma catecholamines as it occurred in sham-operated rats.

The influence of alprazolam on the monoaminergic neurotransmitter systems in dysthymic patients. Relationship to clinical response

The effects of alprazolam (1.5 mg/die) on the levels of the monoaminergic neurotransmitter metabolites, on the activity of the hypothalamic-pituitary-adrenal axis and on clinical outcome in subjects with primary late-onset dysthymia were investigated. Drug treatment significantly decreased plasma and urinary cortisol levels, serotonin platelet-bound and urinary 3-methoxy-4-hydroxyphenylglycol concentrations, while it increased plasma homovanillic acid (HVA) concentrations. Significant relationships were observed between neurochemicals and global scores or some items of the Hamilton Depression Rating Scale, before and after treatment. Patients responded positively (73%) to the therapy; clinical outcome was significantly correlated with plasma and urinary HVA levels. Collected data seem to support the hypothesis that central monoaminergic systems are in part involved in therapeutic response to alprazolam.

Evaluation of the reperfusion syndrome after liver ischemia in the rat

Hepatic surgery in man often requires a transient interruption of the blood flow to the liver. After the vascular declamping the hepatic reperfusion induces a group of phenomena commonly called "reperfusion injuries." The aim of this study was to evaluate the presence and effect of vasoactive agents that could induce the acute pulmonary arterial hypertension which contributes to reperfusion injury. Wistar rats were used. The hepatic ischemia was induced by crossclamping the whole hepatic hilus for 20, 40, and 60 min. In control experiments a sham operation was performed. Blood samples were collected from the suprahepatic inferior vena cava. Strips of the main pulmonary artery were set up in an isolated organ bath and tested for the response to noradrenaline, adrenaline, KCl, and plasma samples. Plasma levels of catecholamines were determined by high-performance liquid chromatography. Plasma concentration of noradrenaline significantly increased from 1.6 +/- 0.4 (control) to 10.8 +/- 2.9 ng.ml-1 and adrenaline concentration rose from 2.7 +/- 0.7 to 38.7 +/- 7.6 ng.ml-1 after ischemia. Noradrenaline potency, compared to control values, significantly increased after prolonged liver ischemia. The plasma samples collected after prolonged liver ischemia caused a greater contraction of the pulmonary artery than from control plasma. This contraction is partially inhibited by phentolamine. We conclude that hepatic ischemia modifies the response of the pulmonary artery to exogenous noradrenaline. At the same time it induces an increase in the plasma levels of adrenaline and noradrenaline. The resulting combined effect may cause the pulmonary hypertension which has been observed in reperfusion injury.

Catecholaminergic, neuroendocrine and anxiety responses to acute psychological stress in healthy subjects: influence of alprazolam administration

We studied the effect of alprazolam (APZ) in 12 healthy volunteers on the psychological stress-induced activation of emotion and on the pituitary-adrenal, adrenomedullary and sympathoneuronal systems. After 3 days of placebo or APZ (1 mg/day orally) administration, we examined plasma levels of adrenocorticotropic hormone, cortisol, L-3,4 dihydroxyphenylalanine, dopamine, norepinephrine (NE), epinephrine, metanephrine, normetanephrine, homovanillic acid, vanillylmandelic acid, 3-methoxy-4-hydroxy phenyglycol, urinary levels of cortisol and catecholamines, circulatory responses and state anxiety levels in subjects undergoing psychological stress based on viewing horror, violence, danger and war film clips. Film viewing produced modest rises of state anxiety levels, of plasma NE concentration and of diastolic blood pressure in both the placebo and drug groups. APZ significantly reduced anxiety levels at the beginning of the experimental session and caused a decrease of noradrenergic and dopaminergic neurotransmitter and cortisol concentrations. Our data suggest that APZ reduced anxiety related to the expectation of the event, while the circuitry between structures responsible for anxiety and peripheral sympathoneural function was still found to be partly sensitive to film viewing.

Normal-range plasma catecholamines in patients with generalized and acrofacial vitiligo: preliminary report

BACKGROUND

There is a body of evidence that neutral factors may play a role in the pathogenesis of vitiligo.

OBJECTIVE

We look for the existence of a relationship between vitiligo and monoaminergic systems.

METHODS

We use high-pressure liquid chromatography to measure the plasma level of catecholamines, their precursor 3,4-dihydroxyphenylalanine and their metabolites 3-methoxy-4-hydroxy phenylglycol (MHPG), normetanephrine (NMN), metanephrine and homovanillic acid (HVA). Forty patients with the generalized (n = 31) and acrofacial (n = 9) types of vitiligo are studied.

RESULTS

Significant differences are not found either between males and females or between the entire group of patients and the controls. HVA and NMN levels significantly correlate with age (r = 0.332, p < 0.05, and r = 0.331, p < 0.05, respectively). Significant correlations are also seen either between noradrenergic or between dopaminergic parameters (norepinephrine vs. MHPG, r = 0.326, p < 0.05; dopamine vs. HVA, r = 0.540, p < 0.01). When the patients are grouped on the basis of vitiligo type or age of disease onset, the plasma mean levels of the neural compounds are always nonsignificantly different from those of the controls. However, both catecholamines and metabolites show higher, although not significant, concentrations in patients with a shorter duration of disease.

CONCLUSION

Monoaminergic systems seem unlikely to be related to vitiligo, at least to the generalized and acrofacial types. However, variations cannot be excluded in genetically predisposed individuals during the onset or the active phases of disease.

Simultaneous measurement of total catecholamines and metanephrines in human urine by liquid chromatography with coulometric detection

A simple routine method is described for simultaneous assay of total urinary norepinephrine, epinephrine, dopamine, normetanephrine and metanephrine. An internal standard of 3,4 dihydroxybenzylamine is added to the diluted urine and acidic hydrolysis of the conjugates is followed by reverse-phase HPLC separation and coulometric detection in the redox mode. The method is rapid and precise and it has a broad linear working range for all substances making it suitable for clinical analysis. Examples are shown of excretion patterns of catecholamines and metanephrines for healthy subjects and depressed patients.

[Gastric leiomyoblastoma. Description of a clinical case]

The paper describes a case of gastric myoblastoma, a rare tumour of the smooth musculature most commonly found in the stomach but also encountered outside the digestive tract. The tumour is potentially malignant and the occasional malignant forms feature histologically a large number of clearly atypical mitoses and clinically an aggressive pattern often involving even widespread metastasis. The case presented is that of a 73 year old woman given a Billroth I gastric resection who was in perfect health 7 months later despite the findings of a myoblastoma with some signs of enhanced mitosis.

Aspects of amitriptyline and nortriptyline plasma levels monitoring in depression

Fifty-nine depressed female inpatients were treated with 100 mg amitriptyline (AMT) IM for 4 weeks. Depression ratings and determinations of the parent drug and nortriptyline (NT) were performed weekly. No direct relationship between plasma AMT + NT concentrations and therapeutic response was apparent, but beneficial therapeutic responses and significantly lower side-effect scores were more frequently noted in subjects with concentrations in the 100-200 ng/ml range. AMT + NT concentrations were significantly correlated with age. No significant difference was found in the number of responders between younger and older subjects with two clinical improvement criteria; however, a significant difference emerged when a third more restrictive clinical outcome criterion was adopted. The implications of the present findings for patient treatment and for the interpretation of previous studies are discussed. The data collected point to a possible usefulness of monitoring AMT and NT plasma levels, even if further investigations are needed.

[Adenocarcinoma of the cecal appendix. Presentation of 2 cases and a review of the literature]

Two cases of adenocarcinoma of the vermiform appendix are described. The literature on these rare cancers which are almost always diagnosed at routine histology and whose prognosis is related to Duke grading and staging, is reviewed. The stable cure observed in one patient after 13 years after straightforward caecal resection for cancer of the appendix extending beyond the base of the implant (which today would be handled with hemicolectomy) and then treated for multiple polyps, two of them in a stage of malignant degeneration, suggests a difference of biological behaviour compared to tumours of the other colon districts. In the second case, stress is laid on the unusual extension of the tumour-related inflammation to the skin of the gluteal region.

Noradrenergic output and clinical response in depressed women during amitriptyline therapy

The measurement of the urinary excretion of 3-methoxy-4-hydroxyphenylglycol (MHPG) in 59 unipolar depressed women before and during administration of 100 mg amitriptyline (AMT) i.m. daily for four weeks showed that the patients could be divided into high or low MHPG excretors. An analysis of the excretion course of MHPG and 3-methoxy-4-hydroxy mandelic acid during therapy showed, in most patients, a lower urinary excretion of both these noradrenaline (NA) metabolites in comparison with basal values. Therapy also decreased plasma noradrenaline concentrations and blood pressure values both at rest and on orthostatic challenge. Available evidence seems to suggest that AMT administration caused a lower overall noradrenergic output that might be partially responsible for a diminished sympathetic nervous activity. The authors were unable to confirm that the baseline MHPG level can predict the clinical response to antidepressant treatment and they found no significant correlations between changes in bio-chemical or physiological variables and drug plasma concentrations or clinical response. The possibility that depressed patients might be grouped according to their different NA metabolism needs to be validated in a larger patient sample.

Clinical and biochemical responses to therapy in Alzheimer's disease and multi-infarct dementia

Memory performance, central monoaminergic function and sympathetic nerve activity were studied in patients with dementia of the Alzheimer type (DAT) or with multi-infarct dementia before and after 4 weeks with single or combined drug therapy (choline-piracetam). Analysis of the levels of 3-methoxy-4-hydroxyphenylglycol (MHPG), 3-methoxy-4-hydroxyphenylacetic acid (HVA) and 5-hydroxyindolacetic acid in the cerebrospinal fluid (CSF) and also in urine (plus 3-methoxy-4-hydroxy mandelic acid) showed that the basal values of HVA in the CSF and urine were lower in the more severely demented compared with the mildly demented subjects in both groups. The combined drug treatment resulted in a statistically significant increase in the MHPG level in the CSF of mildly demented subjects of the DAT group, while it seemed not to influence the other monoamine metabolites. The sympathetic nerve activity was similar in both patient groups and was unchanged after therapy. These findings suggest a dopaminergic deficit in advanced stages of the disease and a possible enhancement of the central noradrenergic output with therapy. No effects of therapy on memory performance or correlations between monoamine levels and memory test scores were noted.

Amitriptyline action on sympathetic neuronal function in depressed women

1. Noradrenaline plasma levels and cardiovascular function modifications with orthostatic challenge during therapy were studied in 59 female depressed inpatients treated with 100 mg amitriptyline daily by intramuscular route for 4 weeks. 2. Therapy induced an increase in pulse rate in supine and upright positions, a decrease of noradrenaline levels and modified standing systolic and (partially) diastolic blood pressure, particularly in elderly subjects. 3. No correlation between neurotransmitter or functional changes and drug plasma levels was noted. 4. The supposed lower noradrenergic output together with blood pressure drop in both positions suggests a reduced sympathetic tone.

Viloxazine in depressed women: clinical response and cardiovascular effects

The antidepressant effect of viloxazine (300 and 500 mg/day) was investigated for 4 weeks in 26 depressed women. The decrease in the Hamilton Depression Rating Scale score indicated a prompt overall clinical improvement, the depressed mood and suicide items showing the highest percent diminution. The highest plasma level of viloxazine was reached at day 7 and decreased during treatment only with the 500 mg dosage. Blood pressure and pulse rate responses to orthostatic stress were slightly affected and showed few untoward cardiovascular reactions to drug treatment. The decrease of noradrenaline plasma levels in both postural positions might indicate a lower sympathetic nervous system tone.

Amitriptyline and nortriptyline plasma levels, urinary 3-methoxy-4-hydroxyphenylglycol and clinical response in depressed women

Thirty-eight depressed female inpatients, treated intramuscularly with 100 mg/day amitriptyline (AMT), were monitored to investigate the relationships between plasma levels of the drug and its metabolite nortriptyline (NT), the urinary excretion of 3-methoxy-4-hydroxyphenylglycol (MHPG), side effects and clinical response. Considering the whole group, the clinical improvement was better within an intermediate range of AMT plus NT plasma concentrations (100-200 ng/ml). A more favorable outcome was also observed at NT plasma levels below 55 ng/ml. No significantly different percent clinical response among the patient clinical subgroups was observed as well as no significant correlations between MHPG decrease and drug plasma levels.

Assay of urinary vanilmandelic, homovanillic, and 5-hydroxyindole acetic acids by liquid chromatography with electrochemical detection

A reversed-phase liquid chromatographic method with amperometric detection has been developed for the simultaneous determination of the noradrenaline metabolite, vanilmandelic acid, the dopamine metabolite, homovanillic acid, and the serotonin metabolite, 5-hydroxyindole acetic acid, in human urine. After purification by an extraction procedure, the metabolites were rapidly separated under isocratic conditions. Detection and quantification were performed with an electrochemical detector using a carbon paste electrode. The present method is sensitive, selective and, achieves a high degree of precision by the use of isovanilmandelic acid as an internal standard. This provides a suitable tool for clinical and research applications.

Urinary 3-methoxy-4-hydroxyphenylglycol determination using reversed-phase chromatography with amperometric detection

A reversed-phase liquid chromatographic method with amperometric detection has been developed for the determination of urinary 3-methoxy-4-hydroxyphenylglycol. Before and after enzymatic deconjugation, it was purified by an extraction procedure and rapidly quantified under isocratic conditions. The 24-h excretion profile in normal human subjects (eight males and seven females) was determined; our results are consistent with those arrived at in a number of other studies. The present method is highly sensitive and selective; in addition, a good degree of precision is assured by use of 4-methoxy-3-hydroxyphenylglycol as internal standard.

Blood noradrenaline and 5-HT levels in depressed women during amitriptyline or lithium treatment

Noradrenaline levels and platelet and free serotonin concentrations were studied in depressed women in-patients (n=78) before and during amitriptyline (n=41) or lithium treatment (n=37). Pronounced monthly differences in platelet serotonin level have been shown in these subjects before treatment. In all clinical subgroups (neurotic, involutional, manic-depressive patients) a significant fall in platelet serotonin level was observed with amitriptyline medication while an increase was noted with lithium. No significant correlations between serotonin concentrations and clinical outcome were found. Amitriptyline treatment also produced a decrease in peripheral noradrenaline concentration in all subgroups, while an increase was observed with lithium. Some correlations between noradrenaline level and degree of depression were noted in patients treated with amitriptyline or lithium. A more extended analysis of blood amine levels could supply meaningful information on the peripheral action of antidepressive drugs on noradrenaline and serotonin concentrations in depression.

Amitriptyline, nortriptyline plasma levels and clinical response in women with affective disorders

The relationship between the plasma levels of amitriptyline and its metabolite nortriptyline, as well as their side-effects and clinical response, were studied in 102 depressed female in-patients, treated with different dosages of amitriptyline. For 50 and 100 mg dosages, significant positive correlations were found between amitriptyline concentration and the Hamilton amelioration scores, as well as between Hamilton final values and side effects. For depressive neurosis and involutional melancholia best therapeutic responses were yielded at a dosage of 50 mg, while in the treatment of manic-depressive illness, comparable results occurred at a 150 mg dosage. In the depressive neurosis and in the involutional melancholia the upper plasma concentration limits for the therapeutic effect of nortriptyline were identified. The lower plasma concentration limits of amitriptyline and nortriptyline in the treatment of manic-depressive illness were also pointed out.

A sensitive fluorimetric method for determination of platelet-bound and plasma free serotonin

A sensitive and specific fluorimetric assay for blood platelet-bound and plasma free serotonin is described. Serotonin is concentrated and purified on Amberlite CG-50 resin, eluted by 0.15 mol/l HCl and its native fluorescence is read at 295/350 nm. The good recovery (90% about), reproducibility and sensitivity (the smallest amount detectable is 5 ng) make the assay particularly useful for the detection of free serotonin in plasma. The whole procedure is rapid enough to permit the analysis of 15--20 samples within one working day and thus the method is suitable for routine determination of serotonin in biological specimens.