ABSTRACT
INTRODUCTION: Dementia occurring in young people may be difficult to recognize. We compared the time to diagnosis between young- (YOD, age < 65) and late-onset dementia (LOD). METHODS: Time between the onset of symptoms and the diagnosis was measured in YOD and LOD patients consecutively seen in a cognitive neurology clinic. Multivariable regression analyses were performed to identify determinants of time to diagnosis. RESULTS: Mean time to diagnosis in 95 YOD patients was 11.2 months longer than in 73 LOD patients (p = 0.022). The delay was driven by a longer time taken by YOD patients to be seen in the specialist centre, which in turn was related to the presence of language disturbances and coexisting depression. DISCUSSION: Young people take longer than elderly people to receive a dementia diagnosis because they take longer to be referred to dementia specialist centres. More awareness on YOD is needed in primary care and the public.
Subject(s)
Dementia , Adolescent , Age of Onset , Aged , Dementia/etiology , Humans , Referral and ConsultationABSTRACT
Presenilin1 (PSEN1) gene is the most common known genetic cause of early-onset familial Alzheimer's disease. We describe an Italian family with the known p.Ala260Gly mutation in PSEN1 gene. The presence of an asymptomatic 64-year-old male carrying the mutation provides evidence of a possible incomplete penetrance leading to a wider range of age at onset. In order to evaluate whether or not epigenetic modifications could contribute to the phenotypic heterogeneity, we assessed global DNA methylation levels which resulted significantly higher in the three females than in their presymptomatic brother. The study suggests that DNA methylation can contribute to slowing down or possibly protecting from the manifestation of symptoms even in monogenic diseases, emphasizing the great complexity of familial Alzheimer's disease.
Subject(s)
Alzheimer Disease , Age of Onset , Alzheimer Disease/genetics , Female , Humans , Male , Middle Aged , Mutation/genetics , Penetrance , Presenilin-1/geneticsABSTRACT
Rheumatoid arthritis (RA) is an aggressive articular autoimmune disease that causes deformities and disability. The temporomandibular joint (TMJ) might be affected by this disease. Few controlled studies have evaluated bite force (BF) and oro-facial manifestations of this disease. To characterise oro-facial alterations in patients with RA, correlate these results with clinical and disease activity parameters and correlate BF with hand strength (HS). A cross-sectional study of 150 women was performed, (75 RA patients (RA group) and 75 healthy individuals (control group). The presence of articular sounds, pain on palpation of masseter, temporal and TMJ lateral pole, changes in occlusion, range of mandibular motion, measurement of BF in the incisor and molar regions and assessment of HS were evaluated. In relation to oro-facial evaluation there were statistical differences between the groups. There was correlation between BF and HS, in the RA group, this correlation was consistent in patients with natural teeth. Patients with RA had lower scores (P < 0·05) in the HAQ, DASH and OHIP-14 questionnaires than the control group. Inverse correlations were found between BF and HAQ, but not between BF and DAS-28, DASH and OHIP-14 questionnaires in the RA group. The women with RA presented more signs and symptoms in the oro-facial region and had a lower BF than the women in the control group. BF was inversely correlated with the overall function (evaluated by the HAQ) in the patients with RA, and there were correlations between BF and HS in the RA patients and in the control group.
Subject(s)
Arthritis, Rheumatoid/physiopathology , Bite Force , Temporomandibular Joint Disorders/physiopathology , Adult , Aged , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Cross-Sectional Studies , Disability Evaluation , Female , Hand Strength , Humans , Middle Aged , Pain Measurement , Quality of Life , Surveys and QuestionnairesABSTRACT
UNLABELLED: investigator either placed or did not place earplugs into the patients' ears (PLUG or noPLUG groups, respectively). Propofol requirements for stable sedation guided by the bispectral index and incidence of postoperative recall of intraoperative events were assessed in a double-blinded fashion. RESULTS: We found high but comparable propofol requirements in both groups (PLUG 4.4+/-1.2 vs. noPLUG 4.2+/-1.0 mg kg-1 h-1, p=NS). The incidence of intraoperative awareness was lower in the PLUG compared to the noPLUG group (16 vs. 56%; P<0.001). CONCLUSION: Although no sedative-sparing effect could be found in patients who wore earplugs during elective orthopedic surgery under spinal anesthesia, we nevertheless recommend using single-use paraffin wax earplugs. Beside their beneficial effect against potential harmful intraoperative noise, they reduce the incidence of intraoperative awareness with recall.
Subject(s)
Anesthesia, Spinal , Ear Protective Devices , Hypnotics and Sedatives/administration & dosage , Intraoperative Awareness/prevention & control , Mental Recall , Propofol/administration & dosage , Aged , Double-Blind Method , Female , Humans , Male , Prospective StudiesABSTRACT
BACKGROUND: To prospectively investigate the performance, sealing capacity and operating room (OR) staff exposure to waste anaesthetic gases during the use of the Cobra perilaryngeal airway (CobraPLA) compared with the laryngeal mask airway classic (LMA). METHODS: Sixty patients were randomly assigned to the CobraPLA or the LMA group. Insertion time, number of insertion attempts and airway leak pressures were assessed after induction of anaesthesia. Occupational exposure to nitrous oxide (N(2)O) and Sevoflurane (SEV) was measured at the anaesthetists' breathing zone and the patients' mouth using a photoacoustic infrared spectrometer. RESULTS: N(2)O waste gas concentrations differed significantly in the anaesthetist's breathing zone (11.7+/-7.2 p.p.m. in CobraPLA vs. 4.1+/-4.3 p.p.m. in LMA, P=0.03), whereas no difference could be shown in SEV concentrations. Correct CobraPLA positioning was possible in 28 out of 30 patients (more than one attempt necessary in five patients). Correct positioning of the LMA classic was possible in all 30 patients (more than one attempt in three patients). Peak airway pressure was higher in the CobraPLA group (16+/-3 vs. 14+/-2 cmH(2)O, P=0.01). The average leak pressure of the CobraPLA was 24+/-4 cmH(2)O, compared with 20+/-4 cmH(2)O of the LMA classic (P<0.001; all values means+/-SD). CONCLUSION: Despite higher airway seal pressures, the CobraPLA caused higher intraoperative N(2)O trace concentrations in the anaesthetists' breathing zone.
Subject(s)
Anesthesia, General/instrumentation , Anesthetics, Inhalation/analysis , Laryngeal Masks , Occupational Exposure/analysis , Adult , Aged , Aged, 80 and over , Environmental Monitoring , Female , Humans , Male , Methyl Ethers/analysis , Middle Aged , Nitrous Oxide/analysis , Respiration, Artificial , Sample Size , Sevoflurane , Spectrophotometry, Infrared , Young AdultABSTRACT
BACKGROUND: Fluid management guided by oesophageal Doppler monitor has been reported to improve perioperative outcome. Stroke volume variation (SVV) is considered a reliable clinical predictor of fluid responsiveness. Consequently, the aim of the present trial was to evaluate the accuracy of SVV determined by arterial pulse contour (APCO) analysis, using the FloTrac/Vigileo system, to predict fluid responsiveness as measured by the oesophageal Doppler. METHODS: Patients undergoing major abdominal surgery received intraoperative fluid management guided by oesophageal Doppler monitoring. Fluid boluses of 250 ml each were administered in case of a decrease in corrected flow time (FTc) to <350 ms. Patients were connected to a monitoring device, obtaining SVV by APCO. Haemodynamic variables were recorded before and after fluid bolus application. Fluid responsiveness was defined as an increase in stroke volume index >10%. The ability of SVV to predict fluid responsiveness was assessed by calculation of the area under the receiver operating characteristic (ROC) curve. RESULTS: Twenty patients received 67 fluid boluses. Fifty-two of the 67 fluid boluses administered resulted in fluid responsiveness. SVV achieved an area under the ROC curve of 0.512 [confidence interval (CI) 0.32-0.70]. A cut-off point for fluid responsiveness was found for SVV > or =8.5% (sensitivity: 77%; specificity: 43%; positive predictive value: 84%; and negative predictive value: 33%). CONCLUSIONS: This prospective, interventional observer-blinded study demonstrates that SVV obtained by APCO, using the FloTrac/Vigileo system, is not a reliable predictor of fluid responsiveness in the setting of major abdominal surgery.
Subject(s)
Monitoring, Intraoperative/methods , Stroke Volume , Abdomen/surgery , Adult , Aged , Algorithms , Echocardiography, Transesophageal , Epidemiologic Methods , Female , Fluid Therapy/methods , Hemodynamics , Humans , Intraoperative Care/methods , Male , Middle Aged , Signal Processing, Computer-AssistedABSTRACT
BACKGROUND: This study investigated the cost-effectiveness of ultrasonographic-guided interscalene brachial plexus blockade (ISB) in comparison with general anaesthesia (GA) for arthroscopic shoulder surgery. METHODS: Forty patients undergoing arthroscopic shoulder surgery received either an ultrasonographic-guided ISB or GA. ISB was performed outside the operation room (OR) and patients were transferred in the OR at the earliest 20 min after block performance. All drugs and disposables were recorded to evaluate the costs for both techniques. The following anaesthesia-related times were defined: ready for surgical preparation (from arrival in the OR until end of anaesthesia induction), OR emergence time (from end of dressing until leaving the OR), anaesthesia control time (from patient's arrival in the OR until readiness for positioning plus time from the end of surgery to patient's discharge from the OR), and post-anaesthesia care unit (PACU) time (from patient's arrival in the PACU to the eligibility for discharge to normal ward). Personnel costs were excluded from statistical analysis. RESULTS: The total costs were [mean (sd)] 33 (9)euro for patients with ISB and 41 (7)euro for those who received GA (P<0.01). The anaesthesia-related workflow was improved in the ISB group when compared with the GA group [ready for surgical preparation 8 (3) vs 13 (5) min, P<0.001; OR emergence time 4 (3) vs 10 (5), P<0.001; anaesthesia control time 12 (4) vs 23 (6), P<0.001; and PACU time 45 (17) vs 70 (20), P<0.001]. CONCLUSIONS: Ultrasonographic-guided ISB is a cost-effective method for arthroscopic shoulder surgery.
Subject(s)
Anesthesia, General/economics , Arthroscopy/economics , Brachial Plexus , Nerve Block/economics , Shoulder Joint/surgery , Adult , Aged , Anesthesia, General/adverse effects , Anesthesia, General/methods , Austria , Cost-Benefit Analysis , Disposable Equipment/economics , Drug Costs/statistics & numerical data , Female , Health Care Costs/statistics & numerical data , Humans , Male , Middle Aged , Nerve Block/adverse effects , Nerve Block/methods , Patient Selection , Ultrasonography, Interventional/economicsABSTRACT
INTRODUCTION: 2-Chlorodeoxyadenosine (cladribine or 2-CdA) is a purine analogue that has been used successfully in hairy cell leukaemia (HCL). Moreover, it has been increasingly used to treat chronic lymphoproliferative syndromes and paediatric acute myeloid leukaemia. Cutaneous side-effects associated with this drug have seldom been described in cases of HCL. PATIENTS AND METHODS: We describe three patients with chronic lymphocytic leukaemia that presented generalized skin eruptions after treatment with 2-CdA. RESULTS: All patients had advanced disease, receiving 2-CdA as a second or third line chemotherapy. Skin lesions were severe and chemotherapy had to be discontinued. Histological examination of skin biopsies showed an eosinophil-rich infiltrate with flame figures, similar to what is observed in Wells' syndrome (eosinophilic cellulitis). Corticosteroids were effective to control the eruptions. CONCLUSIONS: Cutaneous adverse reactions associated with 2-CdA have seldom been observed in the treatment of HCL. However, as this purine analogue has been used in more advanced cases these may be more frequent and severe. The pathophysiology of these lesions is unclear, but it is probably related to drug-induced change in T-cell imbalance in severely immunosuppressed patients.
Subject(s)
Antineoplastic Agents/adverse effects , Cladribine/adverse effects , Drug Eruptions/diagnosis , Exanthema/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Aged , Antineoplastic Agents/administration & dosage , Cladribine/administration & dosage , Diagnosis, Differential , Drug Eruptions/etiology , Drug Eruptions/pathology , Exanthema/chemically induced , Exanthema/pathology , Female , Humans , Middle AgedABSTRACT
Positron emission tomography (PET) imaging of spinal cord in monkeys with a cholinergic tracer demonstrates increased spinal cholinergic activity in response to an analgesic dose of morphine, and this PET result correlates with measurement of acetylcholine spillover into spinal cord extracellular space induced by morphine, as measured by microdialysis. Previous studies in rats, mice, and sheep demonstrate activation of spinal cholinergic neurons by systemic opioid administration, and participation of this cholinergic activity in opioid-induced analgesia. Testing the relevance of this observation in humans has been limited to measurement of acetylcholine spillover into lumbar cerebrospinal fluid. The purpose of this study was to apply a recently developed method to image spinal cholinergic terminals non-invasively via PET and to test the hypothesis that the tracer utilized would reflect changes in local cholinergic activity. Following Animal Care and Use Committee approval, seven adult male rhesus monkeys were anesthetized on three separate occasions. On two of the occasions PET scans were performed using [(18)F] (+)-4-fluorobenzyltrozamicol ([(18)F]FBT), which selectively binds to the vesicular acetylcholine (ACh) transporter in the presynaptic cholinergic terminals. PET scans were preceded by injection of either saline or an analgesic dose of IV morphine (10 mg/kg). On the third occasion, microdialysis catheters were inserted in the spinal cord dorsal horn and acetylcholine concentrations in dialysates determined before and after IV morphine injection. Morphine increased cholinergic activity in the spinal cord, as determined by blood flow corrected distribution volume of [(18)F]FBT in the cervical cord compared to the cerebellum. Morphine also increased acetylcholine concentrations in microdialysates from the cervical cord dorsal horn. The one animal which did not show increased spinal cholinergic activity by PET from this dose of morphine also did not show increased acetylcholine from this morphine dose in the microdialysis experiment. These data confirm the ability to use PET to image spinal cholinergic terminals in the monkey spinal cord and suggest that acute changes in cholinergic activity can be imaged with this non-invasive technique. Following preclinical screening, PET scanning with [(18)F]FBT may be useful to investigate mechanisms of analgesic action in normal humans and in those with pain.
Subject(s)
Analgesics, Opioid/pharmacology , Cholinergic Fibers/drug effects , Cholinergic Fibers/physiology , Morphine/pharmacology , Spinal Cord/drug effects , Spinal Cord/physiology , Acetylcholine/metabolism , Animals , Cholinergic Fibers/diagnostic imaging , Fluorine Radioisotopes , Fluorobenzenes/pharmacokinetics , Macaca mulatta , Male , Microdialysis , Piperidines/pharmacokinetics , Regional Blood Flow/drug effects , Spinal Cord/blood supply , Tomography, Emission-ComputedABSTRACT
Spinally released norepinephrine is thought to produce analgesia in part by stimulating alpha(2)-adrenergic receptors, which in turn leads to nitric oxide synthesis. Also, nitric oxide is known to react with norepinephrine in vivo in the brain to form 6-nitro-norepinephrine, which inhibits neuronal norepinephrine reuptake. In the present study, we tested the hypothesis that formation of 6-nitro-norepinephrine occurs in the spinal cord and that intrathecal administration of 6-nitro-norepinephrine produces analgesia by stimulating norepinephrine release. 6-Nitro-norepinephrine was present in rat spinal cord tissue and microdialysates of the dorsal horn and intrathecal space. Intrathecal norepinephrine injection increased 6-nitro-norepinephrine. 6-Nitro-norepinephrine also stimulated norepinephrine release in dorsal spinal cord in vitro. Intrathecal injection of 6-nitro-norepinephrine produced antinociception and interacted additively with norepinephrine for antinociception. Spinal noradrenergic nerve destruction increased antinociception from intrathecally injected norepinephrine, but decreased antinociception from 6-nitro-norepinephrine. These results suggest a functional interaction between spinal nitric oxide and norepinephrine in analgesia, mediated in part by formation of 6-nitro-norepinephrine. Stimulation of auto-inhibitory alpha(2)-adrenergic receptors at noradrenergic synapses decreases norepinephrine release. Paradoxically, alpha(2)-adrenergic agonist injection increases and alpha(2)-adrenergic antagonist injection decreases norepinephrine release in the spinal cord. 6-Nitro-norepinephrine may be an important regulator of spinal norepinephrine release and could explain the positive feedback on norepinephrine release after activation of spinal alpha(2)-adrenergic receptors.
Subject(s)
Analgesia/methods , Nitric Oxide/metabolism , Nociceptors/metabolism , Norepinephrine/analogs & derivatives , Norepinephrine/biosynthesis , Norepinephrine/metabolism , Pain/metabolism , Receptors, Adrenergic, alpha-2/drug effects , Spinal Cord/metabolism , Animals , Feedback/drug effects , Feedback/physiology , Male , Microdialysis , Nociceptors/drug effects , Norepinephrine/pharmacology , Pain/pathology , Pain/physiopathology , Pain Threshold/drug effects , Pain Threshold/physiology , Posterior Horn Cells/drug effects , Posterior Horn Cells/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Adrenergic, alpha-2/metabolism , Spinal Cord/drug effectsABSTRACT
Nitric oxide has been shown to react under physiologic conditions with norepinephrine (NE) to produce 6-nitro-norepinephrine (6-NO(2)-NE), a compound that enhances NE release in the brain. Previous studies suggest that 6-NO(2)-NE is formed in the spinal cord and stimulates spinal NE release to produce analgesia. The purpose of the current studies was to examine the mechanisms by which 6-NO(2)-NE stimulates NE release in the spinal cord. Crude synaptosomes were prepared from spinal cords of male Sprague-Dawley rats and loaded with [(3)H]NE. Incubation of synaptosomes with 6-NO(2)-NE resulted in a release of NE, with a threshold of 1 microM 6-NO(2)-NE and a maximum effect of 30% fractional release. NE transporter inhibitors desipramine and nomifensine blocked NE release from 6-NO(2)-NE, and desipramine exhibited an IC(50) of 9.6 microM. NE release from 6-NO(2)-NE was dependent on external Na(+), but not Ca(2+) or the activity of guanylate cyclase. 6-NO(2)-NE also blocked uptake of [(3)H]NE into synaptosomes, with an IC(50) of 8.3 microM. These data are consistent with a direct action of 6-NO(2)-NE on noradrenergic terminals in the spinal cord to release NE. This action is independent of guanylate cyclase activation, and most likely shares a common mechanism with classic monoamine releasers such as amphetamine that cause direct release of NE from vesicles into the nerve terminal cytoplasm, leading to extracellular release by reverse transport.
Subject(s)
Norepinephrine/analogs & derivatives , Norepinephrine/metabolism , Spinal Cord/drug effects , Synaptosomes/drug effects , Animals , Calcium/pharmacology , Dose-Response Relationship, Drug , Male , Nitric Oxide/biosynthesis , Norepinephrine/pharmacology , Rats , Rats, Sprague-Dawley , Sodium/pharmacology , Spinal Cord/metabolism , Synaptosomes/metabolismABSTRACT
BACKGROUND: Cholinergic agents produce analgesia after systemic and intrathecal administration. A retrospective review showed that intrathecal neostigmine was more potent in women than in men, suggesting a sex difference in this response. The purpose of this study was to determine whether such a sex difference exists in normal rats and to examine the pharmacologic mechanisms that underlie this difference. METHODS: Male and female rats with indwelling intrathecal catheters received injections of neostigmine, bethanechol (muscarinic agonist), or RJR-2403 (neuronal nicotinic agonist) alone or with atropine (muscarinic antagonist), mecamylamine (nicotinic antagonist), or phentolamine alpha-adrenergic antagonist) with antinociception determined to a noxious heat stimulus to the hind paw. Time versus subcutaneous paw temperature relationships were defined for males and females. RESULTS: Neostigmine produced dose-dependent antinociception with five times greater potency in female than in male rats. Neostigmine-induced antinociception was reversed in male rats by atropine and unaffected by mecamylamine, whereas it was partially reduced by each antagonist alone in females and completely reversed after injection of both. RJR-2403 was more potent in females than in males, whereas there was no sex difference to bethanechol. Phentolamine partially reversed antinociception from RJR-2403 in females. Paw temperature increased more rapidly in females than in males for the same lamp intensity. CONCLUSIONS: These data demonstrate a large sex difference in antinociception to intrathecal neostigmine that is primarily the result of a nicotinic component in females. Phentolamine reversal suggests that part of this nicotinic component may rely on spinal norepinephrine release. A better understanding of this sex difference could lead to development of novel pain therapy for women.
Subject(s)
Analgesics/pharmacology , Cholinergic Agents/pharmacology , Neostigmine/pharmacology , Receptors, Nicotinic/drug effects , Analgesics/administration & dosage , Animals , Cholinergic Agents/administration & dosage , Dose-Response Relationship, Drug , Female , Injections, Spinal , Male , Muscarinic Agonists/administration & dosage , Muscarinic Agonists/pharmacology , Muscarinic Antagonists/administration & dosage , Muscarinic Antagonists/pharmacology , Neostigmine/administration & dosage , Nicotinic Agonists/administration & dosage , Nicotinic Agonists/pharmacology , Nicotinic Antagonists/administration & dosage , Nicotinic Antagonists/pharmacology , Pain Measurement , Rats , Rats, Sprague-Dawley , Reference Values , Sex FactorsABSTRACT
BACKGROUND: Intrathecally administered adenosine receptor agonists have antinociceptive effects in animals, suggesting that intrathecal adenosine might provide analgesia in humans. The authors performed preclinical neurotoxicity studies to define the safety of intrathecally administered adenosine in rats and dogs. METHODS: Eighteen rats with long-term intrathecal catheters received daily injections of saline or 100 microg adenosine for 4 days and were observed for general behavior and thermal nociception before being killed on day 6. Nine beagle dogs were prepared with long-term, lumbar intrathecal catheters and infused continuously with saline or adenosine, 2.4 mg/day for 48 h, then 7.2 mg/day for 26 days. Animals were then anesthetized and perfused with preservative and their spinal cords were examined systematically. RESULTS: No disturbances in neurologic function were detected in either animal species. intrathecal adenosine caused transient sedation in rats and increased muscle tone in dogs, resolving with continued exposure to drug. Neither adenosine-nor saline-treated rats or dogs showed acute thermal analgesia. Adenosine groups did not differ from saline groups regarding histopathology, although a moderate fibrotic and inflammatory reaction was noted in both, and protein concentrations in cerebrospinal fluid were increased in both. CONCLUSION: The current study in rats and dogs failed to provide behavioral or histologic evidence of neurotoxicity from intrathecal administration of adenosine. This provides evidence for the presumption of safety of adenosine in this dose range, and supports phase I safety trials of acute intrathecal adenosine administration in humans.
Subject(s)
Adenosine/toxicity , Spinal Cord/drug effects , Adenosine/administration & dosage , Adenosine/cerebrospinal fluid , Analgesia , Animals , Behavior, Animal/drug effects , Dogs , Female , Humans , Injections, Spinal , Male , Rats , Regional Blood Flow/drug effects , Spinal Cord/blood supply , Spinal Cord/pathology , Urination/drug effectsABSTRACT
BACKGROUND: Intrathecal clonidine produces dose-dependent postoperative analgesia and enhances labor analgesia from intrathecal sufentanil. The authors evaluated the dose-response potency of intrathecally administered clonidine by itself during first stage of labor with respect to analgesia and maternal and fetal side effects. METHODS: Thirty-six parturients requesting labor analgesia were included in this prospective, randomized, double-blind study. Parturients with < 6 cm cervical dilatation received either 50, 100, or 200 microg intrathecal clonidine. The authors recorded visual analog pain score (VAPS), maternal blood pressure and heart rate, ephedrine requirements, and sedation at regular intervals and fetal heart rate tracings continuously. Duration of analgesia was defined as time from intrathecal clonidine administration until request for additional analgesia. RESULTS: Clonidine produced a reduction in VAPS with all three doses. The duration of analgesia was significantly longer in patients receiving 200 microg (median, 143; range, 75-210 min) and 100 microg (median, 118; range, 60-180 min) than 50 microg (median, 45; range, 25-150 min), and VAPS was lower in the 200-microg than in the 50-microg group. In the 200-microg group, hypotension required significantly more often treatment with ephedrine than in the other groups. No adverse events or fetal heart rate abnormalities occurred. CONCLUSIONS: Fifty to 200 microg intrathecal clonidine produces dose-dependent analgesia during first stage of labor. Although duration and quality of analgesia were more pronounced with 100 and 200 microg than with 50 microg, the high incidence of hypotension requires caution with the use of 200 microg for labor analgesia.
Subject(s)
Analgesia, Obstetrical , Analgesics, Non-Narcotic/pharmacology , Clonidine/pharmacology , Hemodynamics/drug effects , Labor Stage, First , Adult , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Injections, Spinal , Pregnancy , Prospective StudiesABSTRACT
BACKGROUND: Spinal adenosine receptor agonists exert antinociception in animal models of acute and chronic pain, but adenosine itself has not been examined. The authors tested the antinociceptive and antihypersensitivity interactions of intrathecal adenosine and its interactions with intrathecal clonidine and neostigmine in rat models of acute thermal nociception and postoperative hypersensitivity. METHODS: Rats were prepared with lumbar intrathecal catheters. Responses to acute noxious stimulation were evaluated by latency to paw withdrawal from a radiant heat source focused on the hind paw. Postoperative hypersensitivity was measured after an incision in the rat hind paw by application of von Frey filaments to the heel adjacent to the wound. An isobolographic design was used to distinguish between additive and synergistic drug interactions. RESULTS: Spinal administration of clonidine and neostigmine, but not adenosine, produced dose-dependent antinociception to noxious thermal stimulation. Addition of adenosine enhanced the antinociceptive effect of clonidine but not neostigmine. In contrast, each of these three agents alone reversed postoperative hypersensitivity. Pretreatment with the alpha-adrenergic antagonist phentolamine completely reversed adenosine's antihypersensitivity action. Adenosine interacted synergistically with neostigmine and additively with clonidine in reducing postoperative hypersensitivity. CONCLUSIONS: These data indicate that intrathecal adenosine by itself has no antinociceptive properties to acute noxious thermal stimulation in rats, but enhances clonidine's antinociception. In contrast, intrathecal adenosine is active against postoperative hypersensitivity by an adrenergic mechanism. Different interactions between adenosine, clonidine, and neostigmine in acute nociception and postoperative hypersensitivity models are consistent with altered central processing of sensory information after peripheral injury.
Subject(s)
Adenosine/pharmacology , Analgesics, Non-Narcotic/pharmacology , Clonidine/pharmacology , Neostigmine/pharmacology , Pain, Postoperative/drug therapy , Animals , Disease Models, Animal , Dose-Response Relationship, Drug , Drug Synergism , Drug Therapy, Combination , Male , Rats , Rats, Sprague-DawleyABSTRACT
Binding of new chemical entities to serum proteins is an issue confronting pharmaceutical companies during development of potential therapeutic agents. Most drugs bind to the most abundant plasma protein, human serum albumin (HSA), at two major binding sites. Excepting fluorescence spectroscopy, existing methods for assaying drug binding to serum albumin are insensitive to higher-affinity compounds and can be labour-intensive, time-consuming, and usually require compound-specific assays. This led us to examine alternative ways to measure drug-albumin interaction. One method described here uses fluorescence quenching of the single tryptophan (Trp) residue in HSA excited at 295 nm to measure drug-binding affinity. Unfortunately, many compounds absorb, fluoresce, or both, in this UV wavelength region of the spectrum. Several types of binding phenomenon and spectral interference were identified by use of six structurally unrelated compounds and the equations necessary to make corrections mathematically were derived and applied to calculate binding constants accurately. The general cases were: direct quenching of Trp fluorescence by optically transparent ligands with low or high affinities; binding of optically transparent, non-fluorescent ligands to two specific sites where both sites or only one site result in Trp fluorescence quenching; and chromophores whose absorption either overlaps the Trp emission and quenches by energy transfer or absorbs light at the Trp fluorescence excitation wavelength producing absorptive screening as well as fluorescence quenching. Unless identification of the site specificity of drug binding to serum albumin is desired, quenching of the Trp fluorescence of albumin by titration with ligand is a rapid and facile method for determining the binding affinities of drugs for serum albumin.
Subject(s)
Serum Albumin/metabolism , Spectrometry, Fluorescence/methods , Tryptophan/chemistry , Binding Sites , Fluorescence , Humans , In Vitro Techniques , Ligands , Statistics as TopicABSTRACT
PURPOSE: Our goal was to demonstrate the feasibility of an in vivo noninvasive method for imaging spinal cord cholinergic terminals using (+)-4-[18F]fluorobenzyltrozamicol ([18F]FBT) and PET. METHOD: In vitro and in vivo experiments in rats were conducted to demonstrate the specific binding characteristics, localization, and time course of [3H]FBT binding in the spinal cord. PET imaging was then performed on seven rhesus monkeys. RESULTS: The rat studies demonstrate high specific binding in the spinal cord with a distribution coinciding with the known distribution of cholinergic terminals. In vivo tracer concentrations in the spinal cord and basal ganglia were of the same magnitude. With use of [18F]FBT and PET in the rhesus monkey, the spinal cord was clearly visualized, with tracer concentration in the spinal cord being approximately one-fourth of that seen in the basal ganglia. CONCLUSION: This work demonstrates the feasibility of imaging cholinergic terminals in vivo in the spinal cord using [18F]FBT and PET.
Subject(s)
Cholinergic Fibers/diagnostic imaging , Fluorobenzenes , Nerve Endings/diagnostic imaging , Piperidines , Spinal Cord/diagnostic imaging , Tomography, Emission-Computed , Animals , Autoradiography , In Vitro Techniques , Macaca mulatta , Male , Radioligand Assay , Rats , Rats, Sprague-DawleyABSTRACT
The evolution of the pattern of nucleolar organiser regions (AgNORs) in circulating lymphocytes during the stable phase and after chemotherapy in CLL was analysed. Peripheral blood smears were stained by the AgNOR technique at diagnosis, during observation follow-up in stable phase, or at the beginning and at the end of chemotherapy in patients with progressive disease. The changes in the AgNOR pattern were compared with those of TTM used as a tumour burden parameter. Among 52 cases that entered the study, 29 were in stable phase and 23 had progressive disease and received chemotherapy. During stable phase, the AgNORs as well as TTM remained constant. In treated patients, the relative reduction of tumour mass was correlated with a decrease in the percentage of lymphocytes containing one AgNOR cluster. The percentage of cells with one compact nucleolus before chemotherapy was inversely correlated with the relative amount of tumor reduction after treatment. We conclude that the AgNOR pattern in CLL describes the cell kinetic changes during the evolution of the disease and is a prognostic factor for tumor reduction after treatment.
Subject(s)
Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Nucleolus Organizer Region/drug effects , Nucleolus Organizer Region/ultrastructure , Aged , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Disease Progression , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/blood , Leukemia, Lymphocytic, Chronic, B-Cell/therapy , Lymphocytes/drug effects , Lymphocytes/pathology , Lymphocytes/ultrastructureSubject(s)
Anesthesia, Spinal , Adrenergic alpha-Agonists/administration & dosage , Analgesics/administration & dosage , Anesthesia, Spinal/methods , Animals , Cholinergic Agents/administration & dosage , Humans , Injections, Spinal , N-Methylaspartate/antagonists & inhibitors , Narcotics/administration & dosage , SafetyABSTRACT
OBJECTIVE: To investigate erythropoietin (EPO) production and the erythropoietic potency of recombinant human EPO in the multiple organ dysfunction syndrome. DESIGN: Randomized, prospective, controlled clinical trial. MATERIALS AND METHODS: Patients received either 600 IU/kg intravenous EPO three times weekly (n = 9) or saline (control, n = 10). MEASUREMENTS: EPO levels, circulating soluble receptors for tumor necrosis factor and interleukin-2, levels of interleukin-6 and intercellular adhesion molecule, and early peripheral blood cell progenitors. RESULTS: EPO production in the control group remained low. Pharmacologic EPO blood levels were associated with increased reticulocyte counts compared with both controls (p < 0.04) and baseline (p < 0.006). Increased levels of soluble receptors for tumor necrosis factor in the treatment group compared with the controls did not prevent this effect. Interleukin 6 inhibited reticulocyte production. CONCLUSION: Despite increased cytokine levels, pharmacologic EPO blood levels were associated with increased reticulocyte counts in patients with multiple organ dysfunction syndrome.