Diversity of arbuscular mycorrhizal fungi in soil from the Pampa Ondulada, Argentina, assessed by pyrosequencing and morphological techniques.

The aim of this study was to assess the effects of agronomic practices on the arbuscular mycorrhizal (AM) fungal community in soils from the Pampa Ondulada region (Argentina), and to compare conclusions reached when using pyrosequencing or a morphological approach. The AM fungal diversity of 3 agricultural exploitations located in the Pampa Ondulada region (Argentina) was assessed by using 454 amplicon pyrosequencing and morphological (based on spore traits) approaches. Two kinds of soil managements are found in these sites: agronomic and non-agronomic. A total of 188 molecular operational taxonomic units and 29 morphological species of AM fungi were identified. No effect of soil management on AM richness was detected. AM fungal communities were more diverse and equitable in the absence of agronomic management. In contrast, the results on ß-diversity varied according to the methodology used. We concluded that agronomic management of soil has a negative effect on AM fungal community biodiversity in the Pampa Ondulada region. We also conclude that both methodologies complement each other in the study of AM fungal ecology. This study greatly improved the knowledge about AM fungi in South America where the molecular diversity of AM fungi was practically unknown.

Percutaneous arthrodesis of sacro-iliac joint: a pilot study.

AIM: Between 15-30% of patients presenting with low back pain have some SI joint involvement. The diagnosis of SI joint involvement in low back pain is quite difficult and depends on a detailed combination of clinical manoeuvres and injection tests. In 5% of patients with SI joint pain, the joint is physically unstable (termed disruption) resulting in ineffective medical and conservative therapeutic options. In this study we present the results of the first 12 cases of SI joint disruption treated using a minimally invasive SI joint arthrodesis system in order to evaluate the safety and the efficacy of this system. METHODS: Medical charts at a single center were reviewed for demographics, perioperative metrics, patient reported outcomes for pain, function and quality of life (NRS, ODI and RDQ respectively), as well as satisfaction with surgery (yes/no) and results of postoperative CT scan. RESULTS: Mean age was 53 years (range 36-71) and all patients were female. Patient reported outcomes at follow up (range 8-18 months) improved clinically as well as statistically as evidenced by a mean improvement in pain on NRS of 4 points, back related function on ODI by 19.4 points, and in quality of life measured using RDQ of 13.6 points (all P=0.01). Local hematoma requiring drainage was apparent in 2 patients. Patient satisfaction was 100%. All 3 month CT scans showed initial fusion. CONCLUSION: The results of this study confirm that MIS SI joint fusion using the iFuse Implant System is safe and effective method of treating patients with SI joint disruption.

Detection of arbuscular mycorrhizal fungi associated with pecan (Caryaillinoinensis) trees by molecular and morphological approaches.

Arbuscular mycorrhizal (AM) fungal community associated with pecan (Caryaillinoinensis) roots and rhizospheric soils was assessed by spore isolation and morphological characterisation and by pyrosequencing of AM molecular markers. The AM fungal community associated with pecan growing in the field, was always more diverse than that associated with pecan growing in containers. This was not observed when AM richness was studied, suggesting that soil disturbance by a reduction in host plant richness leads to a less equitable distribution of AM fungal species, in contrast to natural soils. The chosen primers (AMV4.5F/AMDGR) for pyrosequencing showed high AM fungal specificity. Based on 97% sequence similarity, 49 operational taxonomic units (MOTUs) were obtained and, amongst these, 41 MOTUs corresponded to the Glomeromycotaphylum. The number of obtained AM sequences ranged from 2164, associated with field samples, to 5572 obtained from pecan trap pot culture samples, defining 30 and 29 MOTUs, respectively. Richness estimated by conventional species identification was 6 and 9 AM fungal species in soil and pot samples, respectively. Claroideoglomuslamellosum, Funneliformismosseae and Entrophosporainfrequens were the only taxa detected using both techniques. Predominant sequences in the pecan rhizosphere samples, such as Rhizoglomusirregulare and other less abundant (Dominikiairanica, Dominikiaindica, Sclerocystissinuosa, Paraglomuslaccatum), were detected only by pyrosequencing. Detection of AM fungal species based on spore morphology, in combination with molecular approaches, provides a more comprehensive estimate of fungal community composition.

Trazodone for deafferentation pain. Comparison with amitriptyline.

We report a clinical multicentre experience with antidepressant agents (trazodone and amitriptyline) in the treatment of chronic pain due to deafferentation. Forty five patients were admitted to the study; most of them with oncological peripheral nerve lesions. Almost all of them were already being treated with NSAID in association with weak or strong opioids. A random double blind study was performed: 23 patients were treated with trazodone, 22 with amitriptyline. In the assessment of results, pain intensity, hours of sleep, hours standing and lying, side effects, mood, anxiety and weakness were all taken into consideration. The therapeutic analgesic efficacy of the two drugs proved to be similar.

CSF leukotriene C4 following subarachnoid hemorrhage.

Leukotrienes derive from arachidonic acid metabolism via the lipoxygenase pathway and modulate several cellular events. In the central nervous system, leukotrienes are mainly synthesized in the gray matter and in vascular tissues. Their production is enhanced in ischemic conditions and in experimental subarachnoid hemorrhage (SAH). Previous studies have indicated the ability of the leukotrienes C4 and D4 to constrict arterial vessels in vivo and in vitro and have suggested their involvement in the pathogenesis of cerebral arterial spasm. In the present study, the authors measured lumbar and cisternal cerebrospinal fluid (CSF) levels of leukotriene C4 in 48 patients who had suffered aneurysmal SAH. In 12 of the cases, symptomatic and radiological spasm was evident. The mean lumbar CSF level of immunoreactive-like activity of leukotriene C4 (i-LTC4) was significantly higher (p less than 0.005) than in control cases, while the cisternal CSF level was higher than the lumbar mean concentration (p less than 0.005). Patients presenting with vasospasm had significantly higher levels of i-LTC4 compared to patients without symptomatic vasospasm. This is the first report concerning monitoring of i-LTC4 levels in the CSF after SAH. The results of this study suggest that: 1) metabolism of arachidonic acid via the lipoxygenase pathway is enhanced after SAH; 2) the higher cisternal CSF levels of i-LTC4 may be part of the biological response in the perianeurysmal subarachnoid cisterns after the hemorrhage; and 3) the higher CSF levels of i-LTC4 in patients presenting with vasospasm suggest that a relationship exists between this compound and arterial spasm and/or reflect the development of cerebral ischemic damage.

Phosphatases and cathepsin D activities after vasogenic oedema: an experimental study.

The role of two phosphatases (acid and alkaline phosphatase) and a lysosomal aspartyl endopeptidase (cathepsin D) in producing rat brain oedema was studied in 3 different rat cerebral areas (i.e. frontal cortex, hippocampus and striatum) at 1, 2 and 3 d after vasogenic brain oedema induction. The percentage of water content in the frontal cortex increased immediately, 1 d after oedema induction and remained high for 2 and 3 d after oedema induction. In the hippocampus and the striatum the water content only increases 3 d after oedema induction. In the oedematous hemisphere (right), when compared to the contralateral hemisphere (left), the acid phosphatase activity decreases in the hippocampus, while the alkaline phosphatase increases in the frontal cortex and striatum; cathepsin D increases only in the striatum. The changes caused by the enzymatic activities were significant only 2 and 3 d after oedema induction. The results of this study show that: (i) the vasogenic oedema induced in experimental conditions was not sufficient to cause a massive liberation of lysosomal enzymes and (ii) brain areas adjacent (below) to the site of the experimental oedematous lesion (frontal cortex) were influenced by oedema induction.

Usefulness of sagittal computed tomography in neurosurgery.

Sagittal section tomographic images can be obtained either directly or by an electronic reconstructing procedure. These two techniques are extremely useful for neurosurgeons because it is possible to obtain a better clinical and pathological evaluation of the lesion. This procedure is almost recommended in case of pituitary adenoma, cerebello-pontine angle neoplasms, orbital lesions and brain-stem lesions. The authors show the results of the experience of the University of Pavia and discuss the true indications to this neuroradiological technique.

Outcome following acute supratentorial subdural hematoma in pediatric age.

The authors report their experience in surgical treatment of 39 cases of acute subdural hematoma, followed by intensive therapy and physiokinesitherapy. The causes of head injuries, types of fractures, localization of the hematomas, concomitant lesions, diagnostic and therapeutic clinical features are discussed. The most common neurological evaluation scales for rating the state of comas are used for comparing the cases of head injury in adults (Glasgow Coma Scale) and in children (Children's Coma Scale). The Authors also report clinical follow-up, morbidity, and general mortality rate. Moreover, they emphasize the frequency and clinical importance of cases with unapparent symptomatology and demonstrate that extrinsic eye movement is a very important factor for prognostic evaluation.

Growing skull fractures of childhood. Case report and review of 132 cases.

Authors report a case of growing skull fracture, unusual complication of linear skull fracture in infancy and childhood. A review of 132 cases reported in literature is done with an analysis of general characteristics of this lesion. The most common localization is parietal (50%); clinical presentation is represented by development of seizures (54 cases), focal neurological deficit (57 cases) or loss of consciousness (50 cases). In 50% of cases interval time between head injury and first symptom varies between 1 day and 1 year. After the first year of age the 34.4% of patients develop seizures and 59% present loss of consciousness. Among patients from 1 day to 6 months of age, 46% develop seizures, 38% focal neurological deficit and 21% loss of consciousness. Asymptomatic presentation is more common in fronto-parietal or fronto-parieto-occipital localizations. In parieto-occipital and occipital localization (30 cases), 13 patients (43.3%) have seizures, 36.7% a focal neurological deficit and 60% loss of consciousness. In parieto-temporal localization there is a higher probability of seizures (62.5%) and loss of consciousness (62.5%). The long-term follow-up and the functional recovery in patients which undergo surgery is linked to the clinical presentation and early diagnosis.

Enzymes related to energy metabolism in human gliomas.

The evaluation of the specific activity of some enzymes related to energy transduction was performed in 7 fresh samples of malignant gliomas and in 4 samples of normal brain tissue. Compared with normal brain tissue, the hexokinase, phosphofructokinase and citrate synthase activities are lower; the lactate dehydrogenase and succinate dehydrogenase are unchanged, while glucose-6-phosphate dehydrogenase and NADP+-isocitrate dehydrogenase activities are higher in gliomas.

Peripheral PICA aneurysm. Case report.

One case of aneurysm of the right distal posterior inferior cerebellar artery (PICA), arising from the telo-velo tonsillary segment, is reported; the patient, a 73 years-old woman, was successfully treated by clipping procedure. Few similar cases are reported in literature. Among all intracranial aneurysms, PICA aneurysms account for 0.5-0.7%; most of them arise from vertebro-basilar junction, while only 72 distal PICA aneurysms are reported in literature, till now, with complete anatomo-radiological study. We recommend four vessel angiography because these aneurysms are likely to be missed. When determining the surgical approach it is important to know from which segment the aneurysm arises.

Venous saclike aneurysm of the central nervous system.

A case of cerebral venous saclike aneurysm of the parietal cerebral cortex is presented with surgical and histological confirmation. Computed tomographic findings are non-specific but very useful for detecting the lesion. Angiographic findings are not so obvious as with an arteriovenous malformation, but are necessary for the final diagnosis of a cerebral varix.

Experimental isobaric subarachnoid hemorrhage: regional mitochondrial function during the acute and late phase.

Patients treated for aneurysmal subarachnoid hemorrhage show, in the long-term follow up, an elevated rate of cognitive disturbances that are mainly related to the impact of the initial bleeding: the neurotoxic effects of blood deposition in subarachnoidal spaces may result in a diffuse encephalopathy, but the intrinsic mechanism and the biochemical correlates are not known. In the present study we have evaluated mitochondrial function after experimental induction of subarachnoid hemorrhage. Mitochondrial function was evaluated in four different rat brain areas (frontal cortex, occipital cortex, hippocampus, and brain stem) after experimental isobaric subarachnoid hemorrhage in rats. Subarachnoid hemorrhage was induced by injecting 0.07 mL of arterial autologous blood into the cisterna magna. Intracranial pressure did not significantly increase. The nonsynaptic mitochondrial fraction was isolated from different rat brain areas, and the maximal rate of enzymatic reactions of some key enzymatic activities related to the Krebs cycle [nicotinamide adenine dinucleotide (oxidized form) (NAD+)-isocitrate dehydrogenase, citrate synthase, and succinate dehydrogenase] and of the electron transfer chain (cytochrome oxidase) were evaluated. The nonsynaptic mitochondrial fraction was utilized also to check parameters related to the mitochondrial respiration: state 3, state 4, uncoupled state, respiratory control ratio, and adenosine 5'-diphosphate/oxygen ratio. The biochemical parameters were measured at 1 and 72 hours after the subarachnoidal injection of blood. Subarachnoid hemorrhage did not affect the mitochondrial enzymatic activities both at 1 and 72 hours, while the mitochondrial enzymatic activities parameters were significantly affected: in particular, a significant decrease of respiratory control ratio in all tested brain areas was demonstrated. The increased mitochondrial vulnerability in the delayed phases could be one of the biochemical correlates of post-hemorrhagic encephalopathy.

Cell kinetics aspects of human malignant neuroepithelial tumors: a follow-up study.

The prognostic value of proliferative activity and DNA distribution (ploidy), determined by flow cytometry (FCM), was evaluated in 38 cases of human malignant neuroepithelial tumors. No statistically significant correlation was found between flow cytometric data and clinical outcome. In particular, there was no significant difference between mean survival in cases with percentage of cells in S-phase lower and higher than 5%, respectively. In 21 cases with unimodal DNA distribution, the mean survival was 11.7 months; in 17 cases with bimodal DNA distribution, the mean survival was 12.5 months. The difference was not statistically significant. In our experience, proliferative activity and ploidy do not correlate well with the clinical course and survival of patients with malignant neuroepithelial tumors. However, application of FCM may provide, aside from histopathologic examination, additional biologic information that may be valuable in understanding the variation observed in the course of individual patients.

[Giant and intracavernous aneurysms of the carotid arteries. Their treatment by extracranial-intracranial bypass and gradual occlusion of the carotid artery in the neck]. / Aneurismi giganti ed intracavernosi della carotide. Loro trattamento mediante by-pass extra-intracranico ed occlusione graduale della carotide al collo.

Intracavernous aneurysms are a clinical diagnostic and technical problem. The risk of a direct surgical clipping, whenever possible, is high. Carotid ligation remains the classical surgical treatment for inaccessible aneurysms. Internal carotid artery (ICA) ligation is more effective than common carotid artery (CCA) ligation but carries a higher risk of cerebral ischaemia. The performance of ipsilateral extra-intracranial by-pass (EIAB) helps to maintain blood flow in the cerebral hemisphere. It also decrease the collateral flow formation through the circle of Willis with turbulence in the aneurysmal sac, thus enhancing thrombosis. A series of five cases is reported. The results are satisfactory except in one patient who died in the immediate postoperative period for malignant hemispheric edema, in spite of the patent by-pass. The EIAB can reduce but not eliminate the risk of ischaemic complications related to ICA ligation.

[Cerebral vasospasm. Clinical and experimental aspects]. / Il vasospasmo cerebrale. Aspetti clinico-sperimentali.

A large number of experimental data suggest a possible biochemical hypothesis for the trigger stimulus of cerebral vasospasm after subarachnoid hemorrhage (SAH). Among several classes of possible spasmogens, arachidonic acid metabolites may play a primary role. Authors have measured with radioimmunoassay technique (R.I.A.) the levels of four arachidonate metabolites (PGD2, TxB2, 6-keto-PGF1 alpha and i-LTC4) in lumbar and cisternal cerebrospinal fluid (CSF) of patients admitted with diagnosis of aneurysmal SAH. In all cases a significant activation of arachidonate metabolism is found, if compared to control cases. Patients with demonstrated vasospasm have significantly higher CSF levels of PGD2 and i-LTC4. Cisternal CSF levels of four metabolites are significantly higher than lumbar CSF levels. This suggests the correlation between subarachnoidal clot extension and the risk for vasospasm. Authors also present an experimental animal model of SAH, which is reliable from a pathological standpoint. This model could be therefore used in the study of neurochemical and neuropharmacological aspects of SAH.

[Chemotherapy and immunotherapy of intracranial malignant gliomas]. / Chemioterapia ed immunoterapia dei gliomi maligni endocranici.

Although in recent years a great attempt has been made in brain tumor chemotherapy, this therapeutic approach appears to be conditioned by a large number of problems such as cell kinetics, tumor growth modalities, and drug delivery. Therefore only a small number of drugs (BCNU, CCNU, streptozotocin, and procarbazine) clearly demonstrate effectiveness against these tumors. Immunotherapy raises the same and other problems. In fact, if immune reaction is quite possible inside the brain, unfortunately current immunostimulant methods are unable to produce significant improvements.

Idiopathic hydrocephalic dementia in aging brain the neurosurgical approach.

On the basis of our 16 years' experience, we have treated 36 patients by extrathecal shunt for idiopathic normal pressure hydrocephalus. All patients were submitted to clinical evaluation, neuroradiological, and neuropsychological (Mini Mental Test) tests. Seventy-six per cent of patients showed a significant clinical improvement. No change was found in 24% of them, including two patients who died. In a group of 13 patients we measured the level of main neurotransmitter metabolites (MHPG, HVA, 5-HIAA) in order to evaluate the functional status of encephalic monoaminergic system. If care is taken to make a correct diagnosis and give adequate treatment with a shunt, hydrocephalic dementia has a good prognosis.

Bioenergetics of different brain areas after experimental subarachnoid hemorrhage in rats.

We studied energy metabolism after experimental subarachnoid hemorrhage in rats. Four different cerebral areas were tested: frontal cortex, occipital cortex, hippocampus, and brainstem. Vmax of the following enzymatic activities was evaluated: in the homogenate: hexokinase, phosphofructokinase, and lactate dehydrogenase for the glycolytic pathway, and glucose-6-phosphate dehydrogenase for the hexose monophosphate shunt; in the purified nonsynaptic mitochondria: NAD+-isocitrate dehydrogenase, citrate synthase, and succinate dehydrogenase for the Krebs cycle, and cytochrome oxidase for the electron transfer chain. We also evaluated some parameters related to the respiration of nonsynaptic mitochondria (State 3, State 4, uncoupled state, respiratory control ratio, and ADP:O ratio). Subarachnoid hemorrhage did not significantly affect Vmax of the enzymatic activities related to anaerobic and aerobic metabolism; however, mitochondrial respiration was affected, particularly in the presence of NADH-producing substrates (glutamate + malate).