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1.
Injury ; : 111534, 2024 Apr 04.
Article En | MEDLINE | ID: mdl-38677890

INTRO: Distal growth core fractures of the femur are the third most common fracture in patients older than 10 years. These fractures result from high-energy trauma and have a high risk of evolving into growth disorders. The classification most used to describe these types of fractures is that described by Salter and Harris. Special clinical cases often occur in clinical practice that are not described in the classifications used. In our study, we analyzed and further focused on new fracture patterns related to pediatric epiphyseal detachments not easily described by the normal classifications currently used in the literature. MATERIALS AND METHODS: From January 2020 to December 2022, we treated 2 male clinical cases with epiphyseal detachments of the distal femur that could not be classified according to the Salter and Harris classification. age of the patients was 10 and 11 years, respectively; for both patients, the traumatic mechanism was a direct trauma to the right knee at high speed using an electric scooter; Serious clinical and radiographic follow-ups were performed at month 1, month 3, month 6, month 12, and month 24 from the date of surgery. DISCUSSION: Distal femur fractures represent a challenge for the orthopedics because they have a high incidence of complications. In our experience, there has been an increase in this type of injury caused using recently developed electric vehicles, which can reach considerable speeds. The Salter Harris classification is among the most widely used for fractures involving the growth physis. This classification proved to be rather limiting in the present case, so we decided to classify the fracture as 'Salter Harris III equivalent'. CONCLUSIONS: The fracture examined is a very rare fracture of the distal femur and is not reflected in the classifications currently in use. The patient presented an excellent clinical and radiographic result after surgery with the presence of a shortening of the affected femur in relation to the contralateral one, which suggests that the growth deficit may continue and increase over time for which reason future studies until skeletal maturity will be necessary to quantify the damage to the growth physis.

2.
Mech Ageing Dev ; 205: 111686, 2022 07.
Article En | MEDLINE | ID: mdl-35609733

Recent evidence demonstrates that Crocus sativus L. (saffron) counteracts oxidative stress, mitochondrial dysfunction and neuroinflammation, closely linked to initiation and progression of major brain pathologies. Interestingly, saffron constituents such as crocin, crocetin and safranal can exert antioxidant or toxic effects depending on their endogenous concentration. According to the hormesis principles, at low dose they act as antioxidants in a wide range of brain diseases by upregulating Nrf2 signaling pathway and the expression of vitagenes, such as NAD(P)H-quinone oxidoreductase (NQO1), glutathione transferase (GT), heme oxygenase-1 (HO-1), sirtuin-1 (Sirt1) and thioredoxin (Trx) system. Importantly, neuronal dysregulation of Nrf2 pathway can be a prominent cause of selective susceptibility, under neuroinflammatory conditions, due to the high vulnerability of brain cells to oxidative stress. Here we discuss natural inducers from saffron targeting Nrf2/vitagene pathway for development of new therapeutical strategies to suppress oxidative stress and neuroinflammation and consequently cognitive dysfunction. In this review we also focus on the hormetic effect of saffron active constituents, summarizing their neuroprotective and anti-neuroinflammatory properties, as well as pharmacological perspectives in brain disorders.


Brain Diseases , Crocus , Antioxidants/pharmacology , Antioxidants/therapeutic use , Humans , NF-E2-Related Factor 2 , Oxidation-Reduction , Plant Extracts/pharmacology , Plant Extracts/therapeutic use
3.
Sci Rep ; 6: 19393, 2016 Jan 20.
Article En | MEDLINE | ID: mdl-26786552

Non-fibrillar soluble oligomeric forms of amyloid-ß peptide (oAß) and tau proteins are likely to play a major role in Alzheimer's disease (AD). The prevailing hypothesis on the disease etiopathogenesis is that oAß initiates tau pathology that slowly spreads throughout the medial temporal cortex and neocortices independently of Aß, eventually leading to memory loss. Here we show that a brief exposure to extracellular recombinant human tau oligomers (oTau), but not monomers, produces an impairment of long-term potentiation (LTP) and memory, independent of the presence of high oAß levels. The impairment is immediate as it raises as soon as 20 min after exposure to the oligomers. These effects are reproduced either by oTau extracted from AD human specimens, or naturally produced in mice overexpressing human tau. Finally, we found that oTau could also act in combination with oAß to produce these effects, as sub-toxic doses of the two peptides combined lead to LTP and memory impairment. These findings provide a novel view of the effects of tau and Aß on memory loss, offering new therapeutic opportunities in the therapy of AD and other neurodegenerative diseases associated with Aß and tau pathology.


Long-Term Potentiation , Memory , Protein Aggregates , Protein Aggregation, Pathological , Protein Multimerization , tau Proteins/metabolism , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Alzheimer Disease/psychology , Amyloid beta-Peptides/metabolism , Animals , Disease Models, Animal , Extracellular Space/metabolism , Hippocampus/metabolism , Hippocampus/pathology , Mice , Neurons/metabolism , tau Proteins/chemistry
4.
Neuroscience ; 307: 26-36, 2015 Oct 29.
Article En | MEDLINE | ID: mdl-26314631

For several years Amyloid-beta peptide (Aß) has been considered the main pathogenetic factor of Alzheimer's disease (AD). According to the so called Amyloid Cascade Hypothesis the increase of Aß triggers a series of events leading to synaptic dysfunction and memory loss as well as to the structural brain damage in the later stage of the disease. However, several evidences suggest that this hypothesis is not sufficient to explain AD pathogenesis, especially considering that most of the clinical trials aimed to decrease Aß levels have been unsuccessful. Moreover, Aß is physiologically produced in the healthy brain during neuronal activity and it is needed for synaptic plasticity and memory. Here we propose a model interpreting AD pathogenesis as an alteration of the negative feedback loop between Aß and its physiological receptors, focusing on alpha7 nicotinic acetylcholine receptors (α7-nAchRs). According to this vision, when Aß cannot exert its physiological function a negative feedback mechanism would induce a compensatory increase of its production leading to an abnormal accumulation that reduces α7-nAchR function, leading to synaptic dysfunction and memory loss. In this perspective, the indiscriminate Aß removal might worsen neuronal homeostasis, causing a further impoverishment of learning and memory. Even if further studies are needed to better understand and validate these mechanisms, we believe that to deepen the role of Aß in physiological conditions might represent the keystone to elucidate important aspects of AD pathogenesis.


Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Animals , Humans , Signal Transduction/physiology
5.
Neuropharmacology ; 95: 361-6, 2015 Aug.
Article En | MEDLINE | ID: mdl-25896769

The second messengers cGMP and cAMP have a vital role in synaptic plasticity and memory processes. As such, phosphodiesterases inhibitors (PDE-Is), which prevent the breakdown of these cyclic nucleotides, represent a potential treatment strategy in memory decline. Recently it has been demonstrated that cGMP and cAMP signaling act in sequence during memory consolidation, with early cGMP signaling requiring subsequent cAMP signaling. Here, we sought to confirm this relationship, and to evaluate its therapeutic implications. Combining sub-efficacious doses of the cGMP-specific PDE type 5 inhibitor vardenafil (0.1 mg/kg) and cAMP-specific PDE type 4 inhibitor rolipram (0.01 mg/kg) during the early and late memory consolidation phase, respectively, led to improved memory performance in a 24 h interval object recognition task. Similarly, such a sub-efficacious combination treatment enhanced the transition of early-phase long-term potentiation (LTP) to late-phase LTP in hippocampal slices. In addition, both object memory and LTP were improved after administration of two sub-efficacious doses of the dual substrate PDE type 2 inhibitor BAY60 7550 (0.3 mg/kg) at the early and late consolidation phase, respectively. Taken together, combinations of sub-efficacious doses of cAMP- and cGMP-specific PDE-Is have an additive effect on long-term synaptic plasticity and memory formation and might prove a superior alternative to single PDE-I treatment.


Long-Term Potentiation/drug effects , Memory/drug effects , Nootropic Agents/pharmacology , Phosphodiesterase Inhibitors/pharmacology , Animals , Cyclic AMP/metabolism , Cyclic GMP/metabolism , Dose-Response Relationship, Drug , Drug Synergism , Hippocampus/drug effects , Hippocampus/physiology , Imidazoles/pharmacology , Long-Term Potentiation/physiology , Male , Memory/physiology , Mice, Inbred C57BL , Neurons/drug effects , Neurons/physiology , Rats, Wistar , Rolipram/pharmacology , Tissue Culture Techniques , Triazines/pharmacology , Vardenafil Dihydrochloride/pharmacology
6.
Oncol Rep ; 20(2): 385-90, 2008 Aug.
Article En | MEDLINE | ID: mdl-18636202

Local therapies such as radiofrequency ablation (RFA) represent a valuable choice in limited hepatocellular carcinoma (HCC) and are increasingly used also in advanced tumors. Medical treatments generally gave frustrating results in advanced HCC especially if comorbidities exist. Several biologic non-chemotherapeutic drugs are currently tested in HCC and, among them, octreotide was evaluated in single series of HCC patients reporting conflicting results. We have treated a series of 35 patients affected by advanced HCC (26 M and 9 F; age range: 55-85 years, median: 73 years) with RFA followed by octreotide to primarily evaluate the safety of combined treatment and to give preliminary evaluation on its activity. We have also evaluated serum VEGF changes during the study. Child A and Child B represented 60% and about 34% of the cases, respectively. Only two patients with Child C compensated cirrhosis were included in this study. All patients have multiple liver HCC nodules and one had bone metastases. Two complete responses, 3 partial responses and 23 disease stabilization for at least three months were obtained (overall response rate, 14,2%; clinical benefit, 80%). Mean overall survival was 31.4 months. The combined treatment was well tolerated. Statistically significant correlation was found between serum VEGF and tumor progression. In conclusion, the combination of RFA and octreotide was active in advanced HCC, however, confirmation in a larger series is required.


Antineoplastic Agents, Hormonal/therapeutic use , Carcinoma, Hepatocellular/blood , Catheter Ablation , Liver Neoplasms/blood , Octreotide/therapeutic use , Vascular Endothelial Growth Factor A/blood , Aged , Aged, 80 and over , Biomarkers, Tumor , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/surgery , Carcinoma, Hepatocellular/therapy , Combined Modality Therapy , Disease-Free Survival , Female , Humans , Liver Cirrhosis/blood , Liver Cirrhosis/therapy , Liver Neoplasms/drug therapy , Liver Neoplasms/surgery , Liver Neoplasms/therapy , Male , Middle Aged , Neoplasm Recurrence, Local , Neoplasm Staging , Prognosis , Prospective Studies , Survival Rate , Treatment Outcome
7.
J Craniofac Surg ; 17(3): 552-6, 2006 May.
Article En | MEDLINE | ID: mdl-16770197

Langerhans Cell Histiocytosis is a rare and protean disease of unknown etiology, clinically characterized by single or multiple osteolytic and/or soft tissue lesions. Oral involvement may predate systemic manifestations or mimic infectious/inflammatory disorders. In the present series, oral involvement characterized eight cases of pediatric Langerhans Cell Histiocytosis and oral symptoms represented a very early sign of this disease in four patients. A careful clinical investigation and a proper histologic analysis were required for achieving a definite diagnosis and for confirming clinical suspicion of disease relapse. Immunohistochemistry, that nowadays represents a reliable and accessible ancillary histological technique, allowed the definite diagnosis in all cases of our series.


Histiocytosis, Langerhans-Cell/diagnosis , Mouth Diseases/diagnosis , Child, Preschool , Diagnosis, Differential , Exanthema/diagnosis , Female , Follow-Up Studies , Gingival Diseases/diagnosis , Gingivitis, Necrotizing Ulcerative/diagnosis , Histiocytosis, Langerhans-Cell/pathology , Humans , Immunohistochemistry , Infant , Male , Mouth Diseases/pathology , Mouth Mucosa/pathology , Osteolysis/diagnosis , Recurrence , Stomatitis, Aphthous/diagnosis
8.
J Craniofac Surg ; 17(1): 152-62, 2006 Jan.
Article En | MEDLINE | ID: mdl-16432425

Maxillofacial prosthetic rehabilitation aims to restore anatomic function when serious tissue defects are present, as a result of congenital factors, trauma, or surgery. The aims are both aesthetic and functional, and results are obtained using devices that contain, reconstruct, and fill. This study introduces a technique using methods and materials that are acceptable to the patient in that they satisfy chewing, phonetic, and aesthetic functions, while respecting bone structure and restoring function to the soft tissues without causing trauma to them. Our techniques do not use innovative materials, but ones that are structurally different and that, until now, have not been connected with attachment systems. Acrylic resin, acetylic resin, and silicon are used, each in such a way as to take maximum advantage of each material's characteristics and thus give the best results.


Biocompatible Materials , Palatal Obturators , Prosthesis Design , Resins, Synthetic , Silicone Elastomers , Acrylic Resins/chemistry , Adult , Biocompatible Materials/chemistry , Biomechanical Phenomena , Cleft Palate/surgery , Humans , Infant, Newborn , Intraoperative Care , Male , Middle Aged , Odontogenic Cysts/surgery , Odontogenic Tumors/surgery , Palatal Neoplasms/surgery , Palate, Hard/surgery , Resins, Synthetic/chemistry , Silicone Elastomers/chemistry
10.
Neurology ; 59(12): 1971-3, 2002 Dec 24.
Article En | MEDLINE | ID: mdl-12499494

Fourteen diabetic subjects with gustatory sweating were treated by intracutaneous injections of botulinum toxin type A into the affected facial skin areas. In all subjects, sweating (measured by Minor starch iodine test) ceased within 4 days, with the maximal follow-up time lasting 24 weeks. This therapeutic approach, which could be used to reduce the severity of diabetic gustatory sweating, appears to be long lasting, adverse effect free, and minimally invasive.


Autonomic Nervous System Diseases/drug therapy , Botulinum Toxins/therapeutic use , Diabetes Complications , Sweating, Gustatory/drug therapy , Aged , Autonomic Nervous System Diseases/etiology , Botulinum Toxins/adverse effects , Electrophysiology , Female , Humans , Iodine , Male , Middle Aged , Parasympathetic Fibers, Postganglionic/drug effects , Starch , Sweating, Gustatory/etiology
11.
Brain Res ; 867(1-2): 210-6, 2000 Jun 09.
Article En | MEDLINE | ID: mdl-10837815

Several researches have shown that the spinal reflex transmission in animals, as well as humans, was inhibited by alpha(2)-agonists, due to a disfacilitation of tonic noradrenergic control on motoneuronal output. To understand better the mechanisms regulating certain aspects of motor activity, here we reinvestigated the possible role of noradrenergic systems in modulating reflex activity of the brainstem in humans. To this aim, blink reflex responses (R1 and R2) evoked by electrical stimulation of the supraorbital nerve were electromyographically recorded in healthy volunteers. Both R1 and R2 areas were measured at 10-min intervals before and after i.v. injection of alpha(2)-agonist clonidine (0.5 microg/kg). The substance induced consistent depression of R1, which reached its maximum 40 min after drug administration (-43% of the control values). Ipsilateral R2 area resulted little affected by clonidine (-15% at 50 min), whereas no effects were observed in contralateral R2. Blood pressure values were never altered by drug injections. These results, taken together with previous observations, support the hypothesis that alpha(2)-agonist substances may cause a transient inactivation of noradrenergic neurons, thus releasing neurons involved in the circuitry of the blink reflex from a facilitatory drive. Since clonidine differentially modulated blink reflex responses, it is likely to assume that such a disfacilitation concerns mostly pontine units mediating the R1. However, the complexity of clonidine's effects at multiple pre- and postsynaptic sites does not allow us to exclude that other systems are involved in the alpha(2)-mediated control of facial motoneurons.


Blinking/physiology , Norepinephrine/physiology , Adult , Blinking/drug effects , Blood Pressure/drug effects , Clonidine/administration & dosage , Female , Humans , Male , Middle Aged , Sympatholytics/administration & dosage
12.
Clin Pharmacokinet ; 38(2): 95-110, 2000 Feb.
Article En | MEDLINE | ID: mdl-10709775

In recent years, drug analysis in keratinised matrices, such as hair and nails, has received considerable attention because of several advantages over drug testing methodologies employing body fluids, such as urine or serum. For example, keratinic matrices, such as finger- and toenails, can accumulate drugs during long term exposure. Drugs are incorporated into nails by a double mechanism: (i) deposition into the root of the growing nail via the blood flow in the nail matrix; and (ii) incorporation via the nail bed during growth from the lunula to the beginning of the free margin. Together, these account for a wide retrospective window of drug detection. Nails can provide a good forensic matrix for the detection of drugs of abuse. Indeed, the international literature has reported the use of nail analysis in postmortem detection of drugs of abuse, drug testing in the workplace and drug screening to detect prenatal exposure, even though further studies are needed for correct interpretation of the data obtained. Another application of drug analysis in nails consists of the possibility of detecting the presence of an antimycotic at the site of action during antifungal therapy for patients with onychomycosis. When available, this evidence has permitted drug treatment of a shorter duration and reduced toxicity. However, so far the potential of drug monitoring in nails still lacks harmonisation and validation of analytical methodologies and a better comprehension of the possible correlation between drug concentrations in the matrix and period of exposure.


Forensic Medicine/methods , Nails/chemistry , Pharmaceutical Preparations/analysis , Toxicology/methods , Humans , Nails/physiology
13.
J Chromatogr B Biomed Sci Appl ; 732(2): 509-14, 1999 Sep 24.
Article En | MEDLINE | ID: mdl-10517374

A procedure based on gas chromatography-tandem mass spectrometry for identification and quantitation of lorazepam in plasma and urine is presented. The analyte was extracted from biological fluids under alkaline conditions using solid-phase extraction with an Extrelut-1 column in the presence of oxazepam-d5 as the internal standard. Both compounds were then converted to their trimethylsilyl derivatives and the reaction products were identified and quantitated by gas chromatography-tandem mass spectrometry using the product ions of the two compounds (m/z 341, 306 and 267 for lorazepam derivative and m/z 346, 309 and 271 for oxazepam-d5 derivative) formed from the parent ions by collision-induced dissociation in the ion trap spectrometer. Limit of quantitation was 0.1 ng/ml. This method was validated for urine and plasma samples of individuals in treatment with the drug.


Anti-Anxiety Agents/analysis , Gas Chromatography-Mass Spectrometry/methods , Lorazepam/analysis , Anti-Anxiety Agents/blood , Anti-Anxiety Agents/urine , Humans , Lorazepam/blood , Lorazepam/urine , Oxazepam/chemistry , Reference Standards
14.
Neuroreport ; 10(6): 1225-9, 1999 Apr 26.
Article En | MEDLINE | ID: mdl-10363929

Previous findings in animals demonstrated that the noradrenergic coeruleospinal system exerts a tonic facilitation on spinal reflexes and that activation of alpha2-autoinhibitory receptors can be responsible for a disfacilitation of the spinal activity. To investigate this issue further, we examined whether this system is also involved in descending facilitatory control of spinal motoneurons in healthy humans. The H-reflex technique was utilized to assay the motoneuronal excitability. The ratio between the maximal reflex response (H) and maximal direct response (M) was determined in each subject and was calculated at 10 min intervals before and after i.v. administration of the alpha2-agonist clonidine (0.5 microg/kg). In all subjects a marked decrease of the H/M ratio, due to depression of the H response, occurred 10 min following the clonidine injection and reached its maximum within 30 min. No significant changes of blood pressure values were provoked by drug injections. These results suggest that an autoinhibitory action may be induced by alpha2-receptor activation of locus coeruleus neurons in humans, and that this device may serve as a mechanism for a myotonolytic action on spinal motoneurons.


Clonidine/pharmacology , H-Reflex/physiology , Motor Neurons/physiology , Spinal Cord/physiology , Adrenergic alpha-2 Receptor Agonists , Adult , Blood Pressure , Clonidine/administration & dosage , Female , H-Reflex/drug effects , Humans , Injections, Intravenous , Kinetics , Locus Coeruleus/physiology , Male , Middle Aged , Models, Neurological , Motor Neurons/drug effects , Spinal Cord/drug effects , Time Factors
15.
Neuroscience ; 88(1): 135-50, 1999 Jan.
Article En | MEDLINE | ID: mdl-10051195

We have studied the control of the primary motor cortex on the activity of lemniscal neurons in semi-chronic implanted cats. In each experiment, two to three foci in the primary motor cortex were identified by intracortical microstimulation at low threshold (up to 20 microA) for their capacity to evoke movements of contralateral single limb joints. Neurons belonging to the dorsal column nuclei (main cuneate nucleus and gracile nucleus), or to the ventral posterolateral nucleus, were sampled for their response to stimulation of the peripheral cutaneous fields, as well as the antidromic response to stimulation of the contralateral medial lemniscus and ipsilateral somatosensory cortex, respectively. These neurons were then tested for stimulation of the cortical foci using a current intensity equal to the threshold needed to evoke motor effects, although we reduced the duration of the stimulating trains; thus, we avoided evoking movements which could elicit afferent volleys along the somatosensory paths. It was found that the primary motor cortex was able to modulate the transmission of exteroceptive signals at the level of both dorsal column nuclei and ventral posterolateral nucleus with analogous modalities. In particular: (i) a high percentage of responses, with a prevalence of excitatory effects, was observed when the receptive field of the neurons topographically corresponded to, or was very close to, the joint controlled by a given cortical focus; (ii) in these cases, higher percentages of excitations were observed in tests which concerned the distal segments of limbs than the proximal segments; (iii) the percentage of responses became lower as the neuronal receptive field was located further from the cortical motor target, the pattern being more frequently inhibitory in nature. From a functional point of view, the motor cortex control appears to be organized in a very precise manner. Its excitatory nature might subserve integrative mechanisms by which exteroceptive information arising in a given limb segment would be enhanced by a motor command inducing movements of the same body part. Moreover, a better definition of the afferent input could be obtained by a simultaneous depression of neurons, which send towards the cortex signals from adjacent or more distant cutaneous regions. It can be hypothesized that such an organization of the cortical control could improve the discriminative somatosensory aspects during the execution of explorative movements, besides supplying a sharper cutaneous feedback to the motor cortex.


Cerebral Cortex/physiology , Joints/physiology , Medulla Oblongata/physiology , Motor Activity/physiology , Motor Cortex/physiology , Neurons/physiology , Thalamus/physiology , Animals , Cats , Electric Stimulation , Functional Laterality , Joints/innervation , Microelectrodes , Models, Neurological , Skin/innervation
16.
Arch Ital Biol ; 136(3): 215-23, 1998 Jul.
Article En | MEDLINE | ID: mdl-9645311

The retrograde transport of a tracer has been combined with peroxidase immunocytochemistry to verify whether corticostriatal (CS) neurons contain in their cell bodies high levels of glutamate (Glu) and aspartate (Asp). Injections of WGAapoHRP-Au in the caudate/putamen of adult rats produced retrograde labeling of a large number of layer V neurons of wide regions of the ipsilateral cerebral cortex; fewer labeled neurons were also found on the contralateral side. In all experiments, most CS neurons were seen in the agranular frontal cortex, in both the medial and the lateral subdivisions. Moreover, numerous retrogradely labeled neurons were observed in the cingulate cortex and in the granular parietal cortex, depending on the location of the injection site in the various experiments. The majority of CS neurons examined were immunostained using antibodies against glutaraldehyde-conjugates of Glu or Asp. Glu immunopositive neurons resulted 52-61% of CS neurons. Asp immunopositive neurons ranged between 53% and 62%. In the cortical tissue where Glu and Asp antisera were visualized simultaneously, up to 96% of the CS neurons were immunostained. The latter finding indicates that the populations of Glu and Asp immunopositive neurons are largely segregated and that virtually all cortical neurons projecting to the striatum contain high concentrations of Glu and/or Asp, thus corroborating the hypothesis that CS projections use excitatory amino acids as neurotransmitters.


Amino Acids/physiology , Cerebral Cortex/physiology , Corpus Striatum/physiology , Neurotransmitter Agents/physiology , Synaptic Transmission/physiology , Animals , Aspartic Acid/metabolism , Cerebral Cortex/cytology , Glutamic Acid/metabolism , Gold Colloid , Immunohistochemistry , Molecular Probes , Neurons/physiology , Rats , Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate
17.
J Anal Toxicol ; 22(2): 135-41, 1998.
Article En | MEDLINE | ID: mdl-9547410

Urine specimens containing 11 common beta blockers were processed using solid-phase extraction technology to extract the drugs from the urine matrix, then converted to their cyclic methaneboronates by treatment with methaneboronic acid in ethyl acetate. The compounds tested included acebutolol, atenolol, alprenolol, bisoprolol, betaxolol, carteolol, penbutolol, propranolol, pindolol, timolol, nadolol, sotalol, labetolol, metoprolol, and oxprenolol. The extraction efficiencies were greater than 90% for all drugs tested. The cyclic methaneboronates formed by this procedure generally possessed good chromatographic properties. The mass spectral behavior of the methaneboronates was excellent, with all compounds containing several high mass fragments and every tested compound possessing a unique mass spectrum.


Adrenergic beta-Antagonists/urine , Boronic Acids , Substance Abuse Detection/methods , Adrenergic beta-Antagonists/chemistry , Adrenergic beta-Antagonists/isolation & purification , Boronic Acids/chemistry , Chromatography, High Pressure Liquid , Feasibility Studies , Gas Chromatography-Mass Spectrometry , Humans
18.
Microsc Res Tech ; 36(3): 159-64, 1997 Feb 01.
Article En | MEDLINE | ID: mdl-9080405

We have used a confocal laser scanning optical microscope imaging device and a bioimage-oriented workstation equipped for augmented reality to study the helical sperm head of the octopus Eledone cirrhosa. This approach allows us to study different complex organisational motifs due to the spatial arrangement of linear helical structures. We consider this helical specimen an enlarged copy of one of the most important biostructures governing cell functioning such as chromatin-DNA. Moreover, this very same sample is made of highly compacted chromatin that can be studied at higher resolution, i.e., by means of scanning force microscopy. Fluorescence optical sectioning has been used to enter the spatial organisation. Three-dimensional images of single, twisted, and folded fibers are shown.


Image Processing, Computer-Assisted/methods , Microscopy, Confocal/methods , Sperm Head/ultrastructure , Animals , Chromatin/ultrastructure , Male , Microscopy, Atomic Force , Octopodiformes
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