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CD 63 Cell Expression Detected by Flow-Cytometric Determination and Basophil Activation in Allergic Patients. Int J Immunopathol Pharmacol 2012; 25:1143-7. [DOI: 10.1177/039463201202500432] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Flow cytometry analysis of in vitro activated basophils (BATs) based on the detection of CD63 up-regulation on basophil membrane provides the physician and the clinical laboratory with a novel diagnostic approach, proposed as a promising alternative method for in vitro diagnosis of IgE and non-mediated reactions. We performed an optimized flow cytometric procedure to assess CD63 expression on activated basophils on twenty allergic patients, and compared the results with specific IgE determination (RAST) and skin testing (Prick test).
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Immune response to sublingual immunotherapy in children allergic to mites. J BIOL REG HOMEOS AG 2011; 25:627-634. [PMID: 22217994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Allergic rhinitis (AR) is characterized by Th2 polarized immune response. Specific immunotherapy modifies this arrangement restoring a physiologic Th1 profile. Sublingual immunotherapy (SLIT) is widely prescribed, but there is no early marker of response. The aim of this study is to investigate possible marker of SLIT effectiveness. Thirty children with mite allergy were studied: 15 were treated with drugs alone, 15 with SLIT and drugs on demand. The study lasted 2 years. Visual analogue scale (VAS) for symptoms and medication score were evaluated. Serum cytokines (IL-2, IL-4, IL-6, IL-8, IL-10, IFN-gamma, MCP-1, and TNF-alpha) were assessed by ELISA before and after 1 and 2 year SLIT. SLIT-treated children obtained a significant improvement of symptoms and a reduction of drug use, whereas children treated with a drug alone did not obtained any change. IL-10 significantly increased, whereas Th2-dependent and pro-inflammatory cytokines significantly decreased. In conclusion, the present study demonstrates that 2-year SLIT is capable of inducing immunologic hyporeactivity to mites.
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Efficacy of over-the-counter immunostimulants in the prevention of paediatric recurrent acute respiratory tract infections. Criticisms and pitfalls of available metanalyses. Eur Ann Allergy Clin Immunol 2011; 43:157-161. [PMID: 22145251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
UNLABELLED Preschool children frequently suffer from acute respiratory tract infections (ARTI). Immunostimulants (ISs) are often administered to reduce their impact. This study aimed to establish the efficacy of ISs in the prevention of pediatric ARTI through the analysis of systematic reviews (SRs). We explored Medline database in October 2010 limiting our search to SRs, that included studies on the effectiveness of ISs in the prevention of pediatric ARTI. Six SRs with meta analysis (MA) were found. The studies included showed a low methodological quality and a high statistical heterogeneity. All papers published on journals with impact factor > 1 and a Jadad score > 3 reviewed the efficacy of OM-85. The number needed to treat (NNT) was between 2 and 11, depending on the setting. CONCLUSIONS Pediatric ARTI are a social and health care problem. When they impair the quality of life of the family a course of OM-85 might be warranted. Although scientific knowledge of clinicians may be improved by SRs, MA and aggregation of results may not always be the best way to accomplish this.
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Influenza vaccine administration in rheumatoid arthritis patients under treatment with TNFalpha blockers: safety and immunogenicity. Clin Immunol 2009; 134:113-20. [PMID: 19846344 DOI: 10.1016/j.clim.2009.09.014] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Accepted: 09/29/2009] [Indexed: 12/14/2022]
Abstract
Twenty-eight patients with low-moderate, stable rheumatoid arthritis (RA), under treatment with tumor necrosis factor (TNF) alpha blockers, were immunized at least once with non-adjuvanted trivalent influenza vaccine during three consecutive influenza seasons. Antibodies toward A influenza antigens significantly increased and reached protective levels, still detectable 6 months after vaccination, both in RA patients and healthy controls. Response to B antigen instead was only observed from the second year for healthy controls and in the third year for patients. No significant difference in disease activity and anti-nuclear antibodies was observed as a consequence of vaccine administration, whereas T regulatory cells showed a significant increase 30 days after immunization in RA patients. This study confirms safety of influenza vaccine administration in RA patients treated with TNFalpha blockers. The cohort follow-up revealed the overcoming of poor B vaccine antigen immunogenicity via repeated vaccinations. Finally, protective antibody response was still observed 6 months after vaccination.
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Bone mineral density and body composition in a myelomeningocele children population: effects of walking ability and sport activity. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2008; 12:349-354. [PMID: 19146196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Myelomeningocele causes serious locomotor disability, osteoporosis and pathologic fractures. The aim of this study was to investigate the relationship between body composition, bone mineral density, walking ability and sport activity in myelomeningocele children. 60 patients aged between 5 and 14 yrs with myelomeningocele (22 ambulatory and 38 non-ambulatory), were studied. Fat mass and fat-free-mass were calculated by anthropometry. The bone mineral density at lumbar and femoral neck were evaluated. Bone mineral density at the lumbar and femoral neck was lower than in the normal population. In the non-ambulaty group, bone mineral density was approximately 1 SD lower than in the ambulatory one (p < 0.01). Fat mass was greater than expected but without significantly differences between walking group (mean 26%) and wheel-chair users (25%). Patients practised sport activity had a better bone mineral density and body fat compared with other patients with the same disability. Patients with myelomeningocele have decreased bone mineral density and are at higher risk of pathologic bone fractures. All subjects showed an excess of fat as percentage of body weight and are shorter than normal children. The measurement of bone mineral density may help to identify those patients at greatest risk of suffering of multiple fractures. Walk ability and sport activity, associated with the development of muscle mass, are important factors in promoting bone and body growth, to reduce the risk of obesity and of pathological fractures.
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Evaluation of neutrophil CD64 expression and procalcitonin as useful markers in early diagnosis of sepsis. Int J Immunopathol Pharmacol 2008; 21:43-9. [PMID: 18336730 DOI: 10.1177/039463200802100106] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Quantitation of neutrophil CD64 expression and procalcitonin (PCT) levels in blood samples have been recently proposed as useful tools for early detection of sepsis. To determine the usefulness of these tests, we analyzed blood samples of 112 patients, admitted to an intensive care unit (ICU), presenting clinical symptoms of sepsis, as well as of 50 healthy controls. At the end of the study, a retrospective analysis showed that only 52 of the 112 ICU-patients presented a real sepsis (positive blood culture). The results obtained indicated that of the 52 patients with sepsis, 50 and 49 presented levels of neutrophil CD64 expression >or= 2398 molecules per cell (cut-off determined by receiver operator characteristic analysis) and PCT levels >0.5 ng/ml (cut-off suggested by the manufacturer), respectively. However, the neutrophil CD64 test showed higher specificity in detecting sepsis since 5 out of the 60 ICU-patients without sepsis (negative blood culture), presented CD64 expression levels >or= 2398 molecules per cell, PCT levels >or= 0.5 ng/ml were shown in 27 patients. Moreover, while none of the 50 healthy controls presented a neutrophil CD64 level higher than the cut-off value, 5 patients presented PCT levels >or= 0.5 ng/ml. In conclusion, our data seem to indicate that the quantitation of CD64 expression could be taken into consideration as a sensitive and specific test for early diagnosis of sepsis.
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Neurotrophic factor expression in newborns with myelomeningocele: preliminary data. Eur J Paediatr Neurol 2008; 12:113-8. [PMID: 17881265 DOI: 10.1016/j.ejpn.2007.07.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Revised: 07/12/2007] [Accepted: 07/12/2007] [Indexed: 11/30/2022]
Abstract
BACKGROUND Neurotrophic factors play a crucial role in the stimulation of sprouting, synaptic plasticity and reorganization after spinal cord damage. The aim of this study was to investigate the expression of some neurotrophic factors [brain derived neurotrophic factor (BDNF), glial derived neurotrophic factor (GDNF), and nerve growth factor (NGF)] in the cerebrospinal fluid (CSF) of newborns with myelomeningocele (MMC) and to determine their correlations with this malformation. METHODS To measure the expression of BDNF, GDNF, and NGF, we collected CSF samples of six newborns during the neurosurgical operation to correct the open MMC and of 10 matched controls. Endogenous neurotrophic factor levels were quantified using a two-site immuno-enzymatic assay. The statistical analysis was performed using the Mann-Whitney two-tailed two-sample test. FINDINGS In the CSF of patients analysis of neurotrophic factor expression showed a significant increase of BDNF, GDNF, and NGF compared to the mean level of the control group (445.8+/-82.3, 86.5+/-2.6, and 59.9+/-6.2 pg/mL, respectively, respect to 10.2+/-5.9, 19.9+/-11.3, and 15.3+/-2.6 pg/mL) (p<0.001). INTERPRETATION Our study shows an over-expression of neurotrophic factors in the CSF of newborns with MMC. This neurotrophin up-regulation may stimulate axonal sprouting and synaptic reorganization of the damaged neural cells at the site of spinal cord lesion. The neurotrophic factor up-regulation may represent a particularly important biochemical markers of spinal cord damage and might be associated with the severity of spine injury in MMC patients.
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Multidimensional study on quality of life in children with type 1 diabetes. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2007; 11:249-55. [PMID: 17876960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
AIM To study the Health Related Quality of Life (HRQoL) and metabolic assessment in 33 children affected with type 1 diabetes (18 males, 15 females; mean age 10.3 years). METHODS AND RESULTS We used the Child Health Questionnaire-Parental Form 50 items (CHQ-PF50), measurements of metabolic control and we related them to patient management and family status. Quality of life (QoL) in diabetic children was worse than in the healthy sample. Interestingly, mean and last glycosylated hemoglobin (mean HbAlc r: -.4410 p < .01 and last HbAlc r: -.4012 p < .01), age of patients (r: -.4428; p < .009) and number of glycaemia controls (r: -.37, p < .03) were the most important parameters related to HRQoL parameters. CONCLUSION This multidimensional study stressed that HRQoL is influenced by the metabolic assessment. Moreover, the report examined the parental perception of QoL in children with chronic diseases. Higher number of glycaemia controls/day, better metabolic control, lower age of children and earlier onset of diabetes produced better physical and psychological aspects of QoL. In comparison with adolescent patients, in children with diabetes, factors as number of insulin injections and daily snacks, and the level of education of the mother were not so important to influence QoL. Unexpectedly, in this sample, life habits, family features, and anthropometric parameters did not correlate with specific domains of QoL.
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Urodynamic Evaluation in Children With Lipomeningocele: Timing for Neurosurgery, Spinal Cord Tethering and Followup. J Urol 2007; 177:2319-24. [PMID: 17509349 DOI: 10.1016/j.juro.2007.01.176] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2006] [Indexed: 11/28/2022]
Abstract
PURPOSE We assessed the usefulness of urodynamic testing for determining the optimal timing of surgery and for evaluating the development of bladder function in children with lipomeningocele. MATERIALS AND METHODS We retrospectively evaluated 64 patients (40 females) 3 to 17 years old (mean 8.5) with lipomeningocele. Patients were divided into 3 groups based on age at surgery, ie younger than 12 months (34 patients), 12 to 36 months (17) and older than 36 months (13). All patients underwent urodynamic testing preoperatively and during extended followup (mean 6.5 years, range 3 to 12). RESULTS Bladder capacity and mean detrusor leak pressure improved in all groups but particularly in patients operated on within the first year of life. At the end of the study mean bladder capacity was 420 cc in patients younger than 12 months, 300 cc in those 12 to 36 months old and 260 cc in those older than 36 months (p <0.01), and mean detrusor leak pressure was 37, 54 and 55 cm H(2)O, respectively (p <0.01). At the latest followup 65% of patients in the youngest group had improved urodynamic parameters vs 33% of those 12 to 36 months old and 28% of those older than 36 months. CONCLUSIONS Urodynamic evaluation and the presence of neurological impairment have crucial roles in determining the optimal timing of surgery in patients with lipomeningocele, and in diagnosing the onset of tethered cord. Our data show that early surgical repair seems to reduce the risk of neurological deterioration of the lower urinary tract, and allows a more physiological development of urinary function.
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Prevalence of latex allergy in spina bifida: genetic and environmental risk factors. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2007; 11:149-153. [PMID: 17970230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
AIM OF STUDY To evaluate the prevalence of latex allergy in a population of children with spina bifida (SB) and to assess the role of early exposure to latex products and others risk factors. INTRODUCTION SB is related with an higher incidence of latex allergic reactions. These patients received repeated surgical procedures, implant of latex-containing materials and catheterization. MATERIALS AND METHODS Eighty consecutive subjects affected with SB besides answering a questionnaire, underwent a skin-prick test (SPT) to latex and the determination of the specific serum IgE (RAST CAP) to latex. 40% (32/80) of the patients showed a latex sensitization with specific IgE > 0.7 kU/I but only twelve of the 32 sensitized patients (40%) suffered from clinical reactions to latex (urticaria, conjunctivitis, angioedema, rhinitis, bronchial asthma). Number of surgical procedures, but particularly early exposure to latex and familiarity for allergy are correlated with latex allergy (p < 0.01). CONCLUSION Latex allergy in SB children is multifactorial situation related with a disease-associated propensity for latex sensitization, early exposure and number of surgical procedures. Prophylactic measures to avoid the exposure, not only in the sanitary environment, through the institution of latex-safe routes and every day, prevent potentially serious allergic reactions.
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Loperamide cause of prolonged urinary retention after acute gastroenteritis. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2007; 11:65-7. [PMID: 17405350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
UNLABELLED Urinary retention is uncommon in children and only one case has been described in literature with loperamide treatment. We report the occurrence of prolonged urinary retention in a 10-years-old girl after receiving oral loperamide for an acute gastroenteritis. The first episode of urinary retention lasted for 24 hours; radiological evaluation (Magnetic Resonance, cistography and renal ultrasound) did not find abnormality; it was necessary deplete bladder with catheterism. Previous to the gastroenteritis, diuresis has always been regular and she did not suffer for any neurological or urinary problems. Patient was submitted to, without success, percutaneous posterior tibial nerve stimulation (SANS) and recovered after one year clean intermittent catheterization. CONCLUSION In a period of increasing popularity of self-medical therapy for common children's diseases, paediatricians should be aware of the potential, rare and chronic effects of this type of treatment. Moreover our case suggests that reaction to loperamide should be added to the etiological list of prolonged urinary retention in young patients.
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Abstract
The frequency of latex allergy in children requiring multiple surgery ranges from 16.7% to 65%. The aim of this study was to investigate the safety and efficacy of latex desensitization in a group of 10 patients with a history of multiple surgical procedures and clinically manifested allergy to latex. We selected 10 children (female-male ratio = 5:5), aged 4-16 yr (mean +/- s.d.: 9 +/- 4), with a history of multiple surgical procedures, adverse reactions to latex and positive skin test to latex and/or specific immunoglobulin E (IgE). Latex allergy diagnosis was confirmed by specific provocation tests (cutaneous, sublingual, mucous, conjunctival tests). Rush (4-day) sublingual desensitization was performed with increasing doses of latex extract (ALK Abellò) under patients' tongue until the highest dose of 500 microg of latex. A maintenance therapy (10 drops of undiluted solution three times a week) was recommended. During the 2-yr follow-up mean values of specific IgG4 and IgE, eosinophilic cationic protein and total IgE did not show significant variations. Patients did not manifest any adverse effect during the rush phase and only two patients manifested mild local symptoms during the maintenance therapy. All the challenges showed a reduction in terms of percentage of positivity and mean scores. All the patients showed a reduction of the mean individual score (p < 0.001). Furthermore patients who needed dental examination or surgery underwent such procedures without the occurrence of symptoms. Our preliminary results show sublingual desensitization to latex can be an important therapeutic tool in the management of young allergic patients requiring multiple operations.
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Polyethylene glycol 4000 vs. lactulose for the treatment of neurogenic constipation in myelomeningocele children: a randomized-controlled clinical trial. Aliment Pharmacol Ther 2006; 23:1259-65. [PMID: 16611288 DOI: 10.1111/j.1365-2036.2006.02872.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
AIM To compare the therapeutic effectiveness and tolerability of low daily doses of polyethylene glycol 4000 vs. lactulose in the treatment of neurogenic constipation in children with myelomeningocele. METHODS Sixty-seven children with chronic neurogenic constipation were randomized allocated to receive either polyethylene glycol 4000 (0.50 g/kg) or lactulose (1.5 g/kg) for 6 months. Patients or their parents reported frequency and modality of evacuation and side effects on a diary card. Primary outcome was bowel frequency > or =3/week, and the second one was side effects at the end of treatment. RESULTS Complete remission of constipation was reported by a significantly (P < 0.01) higher number of patients treated with polyethylene glycol compared with lactulose. At the end of the study, 46% patients of polyethylene glycol group and 22% of the lactulose group were asymptomatic. Compared with lactulose, patients treated with polyethylene glycol reported higher bowel frequency (5.1 vs. 2.9 bowel movements/week, P < 0.01) and reduction of encopresis. Neither lactulose nor polyethylene glycol caused clinically-significant serious side effects and palatability was similar. CONCLUSIONS Polyethylene glycol 4000 compared with lactulose provided a higher success rate, without significant side effects, for the treatment of constipation in myelomeningocele children.
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Abstract
INTRODUCTION Children with spina bifida (SB) have a high degree of exposure to latex products as a consequence of repeated surgical procedures, implantation of latex-containing materials and catheterisation. The consequence is a higher incidence of latex allergic reactions. OBJECTIVE The aim of this study is to evaluate the prevalence of latex sensitisation and allergy in a population of children with myelomeningocele (MMC) and to assess the role of associated risk factors. RESULTS Forty-eight percent of the patients (29 out of 60) showed a latex sensitisation with specific IgE >0.7 kU/l while 15% (9 out of 60) were allergic to latex (specific IgE >0.7 kU/l and clinical manifestations). The principal factor correlated with allergy to latex was specific serum IgE to latex (radioallergosorbent test [RAST]) values (p<0.01). Other factors were total serum IgE (paper radioimmunosorbent test [PRIST]) values, number of surgical procedures and familiarity with allergy. CONCLUSION These results underline the importance of prophylactic measures to avoid the exposure, not only in the sanitary environment, through the institution of latex-safe routes, but also in daily life, to prevent potentially serious allergic reactions.
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Abstract
STUDY DESIGN Prospective multidimensional study by means of: (1) clinical assessment, (2) parental-administered questionnaire for general health (CHQ-PF50), and (3) standardised disability measurements. OBJECTIVES To assess the health-related quality of life (QoL) and disability in children with spina bifida (SB) and to correlate them with the clinical picture and our previous study on adolescents with SB. SETTING SB Centre at a University Hospital in Italy. METHODS A total of 29 consecutive children with SB (mean age 11.4, range 4-14 years)were evaluated through Child Health Questionnaire Parental Form (CHQ-PF50), the FIM instrument, and the Barthel index. RESULTS Disability was inversely related only (r=0.49; P=0.007) to the physical aspect of the QoL of children. Similarly, the disability was inversely related (r=0.37; P=0.005) to the emotional aspect of QoL of patient's parents. Unexpectedly, for the mental aspects of QoL of patients, major disability was not associated with higher psychological distress and severe role disability due to emotional problems. At clinical examination, findings especially for continence and number of catheterisations were usually related to deterioration of physical aspects of QoL (r=-2.28; P=0.02) in children. CONCLUSION The multiperspective assessment showed that there is a linear inverse correlation between disability and QoL in children with SB only for physical aspects. Conversely, there is linear inverse correlation between disability and QoL in patient's parents regarding only emotional aspects. Moreover, this study provided useful information for clinical practice underlining that continence problems are those that most affect QoL in children with SB and their parents.
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Dermorphin and deltorphin glycosylated analogues: synthesis and antinociceptive activity after systemic administration. J Med Chem 1999; 42:400-4. [PMID: 9986710 DOI: 10.1021/jm9810699] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the present paper we describe the synthesis of some dermorphin and deltorphin analogues beta-O- and alpha-C-glycosylated on the C-terminal amino acid residue and report their opioid receptor affinity and selectivity as well as their analgesic potency after subcutaneous injection in mice.
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Glycodermorphins: opioid peptides with potent and prolonged analgesic activity and enhanced blood-brain barrier penetration. Br J Pharmacol 1998; 124:1516-22. [PMID: 9723966 PMCID: PMC1565530 DOI: 10.1038/sj.bjp.0701971] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. In order to improve the in vivo stability of the opioid peptide dermorphin we synthesized O-betaglucosylated analogs ([Ser7-O-betaGlc]dermorphin and [Ser7-O-betaGlc(Ac)4]-dermorphin) and C-alphagalactosylated analogs ([Ala7-C-alphaGal]dermorphin and [Ala7-C-alphaGal(Ac)4]-dermorphin). 2. O- and C-glycosylation of dermorphin halved the peptide affinity for brain mu-opioid receptors and the biological potency in guinea-pig ileum assay (GPI). Despite their lower opioid receptor affinity, when administered intracerebroventricularly (i.c.v., 8-40 pmol) and subcutaneously (s.c., 0.5-3 micromol kg(-1)) in rats, glycosylated analogs were two times more potent than dermorphin in reducing the nociceptive response to radiant heat. Acetylation of sugar hydroxyl groups reduces 5-10 times both biological activity on GPI and mu-receptor affinity, whereas the antinociceptive potency was equal to (i.c.v.) or only two-three times lower (s.c.) than dermorphin potency. 3. Blood-Brain Barrier Permeability Index (BBB-PI) of the glycodermorphins was significantly higher than that of dermorphin, indicating a facilitated entry into the brain: O-beta-linked glucoconiugates are expected to enter CNS by the glucose transporter GLUT-1 of the endothelial barrier. However the calculated BBB-PI for the C-alphagalactoside was about two times higher than that of the O-betaglucoside, excluding the implication of GLUT-1 that is known to be selective for O-beta-links and preferring for the exose glucose. 4. The enhanced brain permeability with the subsequent decrease in peripheral dosage of these opioid peptides did not result in lowering constipation.
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Respiratory and cardiovascular effects of the mu-opioid receptor agonist [Lys7]dermorphin in awake rats. Br J Pharmacol 1998; 124:345-55. [PMID: 9641552 PMCID: PMC1565382 DOI: 10.1038/sj.bjp.0701823] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
1. Changes in respiratory variables, arterial blood pressure and heart rate were studied in awake rats after injection of the opioid peptide [Lys7]dermorphin and its main metabolites, [1-5]dermorphin and [1-4]dermorphin. 2. Fifteen minutes after injection, doses of [Lys7]dermorphin producing antinociception (i.c.v., 36-120 nmol; s.c., 0.12-4.7 micromol kg(-1)) significantly increased respiratory frequency and minute volume of rats breathing air or hypoxic inspirates. This respiratory stimulation was reversed to depression by the 5-HT receptor antagonist ritanserin (2 mg kg(-1), s.c.), was blocked by naloxone (0.1 mg kg(-1), s.c.), significantly reduced by the mu1 opioid receptor antagonist naloxonazine (10 mg kg(-1), s.c., 24 h before) but unaffected by peripherally acting opioid antagonist naloxone methyl bromide (3 mg kg(-1), s.c.). Forty five minutes after injection, doses of the peptide producing catalepsy (s.c., 8.3-14.2 micromol kg(-1), i.c.v., 360 nmol) significantly reduced respiratory frequency and volume of rats breathing air and blocked the hypercapnic ventilator response of rats breathing from 4% to 10% CO2. I.c.v. administration of [1-5]dermorphin and [1-4]dermorphin (from 36 to 360 nmol) never stimulated respiration but significantly reduced basal and CO2-stimulated ventilation. Opioid respiratory depression was only antagonized by naloxone. 3. In awake rats, [Lys7]dermorphin (0.1-1 mg kg(-1), s.c.) decreased blood pressure. This hypotensive response was abolished by naloxone, reduced by naloxone methyl bromide and unaffected by naloxonazine. 4. In conclusion, the present study indicates that analgesic doses of [Lys7]dermorphin stimulate respiration by activating central mu1 opioid receptors and this respiratory stimulation involves a forebrain 5-hydroxytryptaminergic excitatory pathway.
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