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1.
Psychopharmacology (Berl) ; 238(12): 3595-3605, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34495367

RESUMO

RATIONALE: Adolescent exposure to ∆9-tetrahydrocannabinol (THC), the psychotropic constituent of cannabis, might affect brain development, and in rodent models leads to long-term behavioral and physiological alterations. Yet, the basic pharmacology of this drug in adolescent rodents, especially when ingested via ecologically relevant routes like aerosol inhalation, commonly referred to as "vaping," is still poorly characterized. Moreover, sex differences exist in THC metabolism, kinetics, and behavioral effects, but these have not been rigorously examined after vapor dosing in adolescents. OBJECTIVES: We investigated the pharmacokinetics and pharmacodynamics of aerosolized THC (30 min inhalation exposure, 25 or 100 mg/ml) in adolescent Wistar rats of both sexes. METHODS: Liquid chromatography/mass spectrometry analysis of THC and its major metabolites was conducted on blood plasma and brain tissue at 5, 30, 60, and 120 min following a 30-min aerosol dosing session. Effects on activity in a novel environment for 120 min after aerosol, and temperature, were measured in separate rats. RESULTS: We found sex-dependent differences in the pharmacokinetics of THC and its active (11-OH-THC) and inactive (11-COOH-THC) metabolites in the blood and brain, along with dose- and sex-dependent effects on anxiety-like and exploratory behaviors; namely, greater 11-OH-THC levels accompanied by greater behavioral effects in females at the low dose but similar hypothermic effects in both sexes at the high dose. CONCLUSIONS: These results provide a benchmark for dosing adolescent rats with aerosolized (or "vaped") THC, which could facilitate adoption by other labs of this potentially human-relevant THC exposure model to understand cannabis effects on the developing brain.


Assuntos
Alucinógenos , Hipotermia , Vaping , Animais , Dronabinol/farmacologia , Feminino , Masculino , Ratos , Ratos Wistar
2.
Int J Immunopathol Pharmacol ; 27(3): 403-12, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25280031

RESUMO

The increased incidence of invasive candidiasis and of patients at risk requires early diagnosis and treatment to improve prognosis and survival. The aim of this study was to set up a ten-protein array-based immunoassay to assess the IgG antibody responses against ten well-known immunogenic C. albicans proteins (Bgl2, Eno1, Pgk1, Pdc11, Fba1, Adh1, Als3, Hwp1, Hsp90 and Grp2) in 51 patients with invasive candidiasis (IC) and in 38 culture-negative controls (non-IC). Antibody levels were higher against Bgl2, Eno1, Pgk1, Als3, Hwp1 and Grp2, than against Adh1, Pdc11, Fba1 and Hsp90, irrespectively of the patient group considered. Moreover, the IgG levels against Bgl2, Eno1, Pgk1 and Grp2 were significantly higher in IC than in non-IC patients. Furthermore, the ROC curves generated by the analysis of the antibody responses against Bgl2, Grp2 and Pgk1 displayed AUC values above 0.7, thus discriminating IC and non-IC patients. According to these results, the employment of the microarray immunoassay (a rapid, sensitive and multiparametric system), in parallel with conventional diagnostics, can help to spot IC patients. This ultimately will allow to initiate an early, focused and optimized antifungal therapy.


Assuntos
Anticorpos Antifúngicos/sangue , Candidíase Invasiva/diagnóstico , Análise Serial de Proteínas/métodos , Proteínas Fúngicas/imunologia , Humanos , Imunoensaio , Imunoglobulina G/sangue , Proteínas Recombinantes/imunologia
3.
Int J Immunopathol Pharmacol ; 25(4): 1029-40, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23298493

RESUMO

Novel technologies that allow simultaneous assessment of multiple biomarkers provide new and promising diagnostic/prognostic approaches. By protein microarrays, here we analyzed amniotic fluids (AF) from 50 women with preterm delivery (PTD) and 50 control women, who delivered at term. In detail, cytokines, chemokines, matrix metalloproteinases and antigen-specific antibodies were assessed. The AF analysis showed significant differences between women with preterm and term delivery in the levels of IL-1alpha, IL-1beta, IL-4, IL-6, IL-8, MCP-1, IFN-gamma and anti-HSV2 IgG. No significant differences were observed in the levels of TNF-alpha, MMP-2, MMP-9 and specific IgG for seven vertically transmitted pathogens. In conclusion, we demonstrated the feasibility of protein microarrays in the diagnosis of early intrauterine inflammation. The significant association between the increased levels of certain cytokines and preterm delivery argues on their relevance as early pathogenetic markers for identification of risk patients.


Assuntos
Líquido Amniótico/química , Corioamnionite/diagnóstico , Nascimento Prematuro/etiologia , Análise Serial de Proteínas/métodos , Adulto , Citocinas/análise , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez
4.
Commun Agric Appl Biol Sci ; 74(2): 363-73, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20222592

RESUMO

To evaluate the effectiveness of alternative options for biocontrol of whiteflies in greenhouse tomatoes, an experiment was carried out during the cropping season 2005-2006 in one of Sardinia's major horticultural districts (S. Margherita di Pula, Cagliari, Italy). Twelve long-cycle and 17 short-cycle tomato crops (8 autumn and 9 spring crops) were surveyed. All of them were treated for insect pest control at the beginning of the growing season, but in 19 out of 29 cases whitefly natural enemies were also released (BCA greenhouses), at least four weeks after the last treatment. The following release programmes were tested: on autumn crops, 1 Macrolophus caliginosus and 12 Eretmocerus mundus/m2; on long-cycle crops, 1 M. caliginosus (released in autumn or spring) and 24 Encarsia formosa/m2 or 48 E. formosa/m2; on spring crops, 1 M. caliginosus and 24 E. formosa/m2 or 48 E. formosa/m2. The cost of each option was fixed at approximately 0.25 Euros/m2. The remaining greenhouses were maintained as controls (no BCA greenhouses). While whitefly and mirid populations were monitored monthly, whitefly species composition and mortality of immature stages were estimated at least twice during the growing season. On short-cycle autumn crops, the release of M. caliginosus and E. mundus produced negligible results in terms of Bemisia tabaci control. On long-cycle and spring crops, even though in June mortality rates in BCA greenhouses were found to be 2- to 3-fold higher than in no-BCA greenhouses, Trialeurodes vaporariorum population growth was not significantly affected by natural enemies. Among the beneficials tested, E. formosa proved to be the most effective; E. mundus and M. caliginosus did not establish well, probably owing to the persistence of insecticide residues, scarce prey availability and intense plant de-leafing. The presence of indigenous natural enemies of whiteflies was observed in most sites, but in general they contributed little to biological control. The present experiment showed that in Sardinian tomato greenhouses the use of beneficial insects may result in inadequate biocontrol of whiteflies. In particular, the application of cultural practices which may disrupt the establishment and development of predator and parasitoid populations should be critically reexamined.


Assuntos
Hemípteros/parasitologia , Hemípteros/patogenicidade , Controle Biológico de Vetores/métodos , Solanum lycopersicum/parasitologia , Animais , Produtos Agrícolas/parasitologia , Interações Hospedeiro-Parasita , Itália , Ninfa/parasitologia , Pupa/parasitologia , Estações do Ano
5.
Brain Res Bull ; 65(4): 297-300, 2005 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-15811594

RESUMO

Rizatriptan represents a major advance in the treatment of migraine attack: inhibition of peripheral trigeminal nerve and constriction of intracranial extracerebral blood vessels have been proposed as its main antimigraine mechanisms of action. Although many studies may suggest that rizatriptan causes highly selective vasoconstriction within intracranial extracerebral vessels (i.e., meningeal arteries), no literature data are available to date on possible cerebral hemodynamic changes in humans after treatment with rizatriptan. The aim of this study was to evaluate the effect of rizatriptan on cerebral blood flow velocity performing transcranial Doppler during spontaneous attacks of migraine without aura. Fourteen patients suffering from migraine without aura were monitored to evaluate mean flow velocity changes on both middle cerebral arteries during migraine attack 30 min before and 120 min after oral administration of rizatriptan 10mg. Monitoring was repeated for 30 min during the pain-free period. All patients turned out to be drug responders and no significant mean flow velocity changes were observed between the pain-free period and pre-treatment phase; besides no significant difference in mean flow velocity value have been detected between the periods after the drug administration during the attack versus both pre-treatment period and pain-free phase. These findings indicate that the antimigraine action of rizatriptan is not associated with clear intracranial cerebral hemodynamic changes and may support its cerebrovascular safety.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Transtornos de Enxaqueca/sangue , Fluxo Sanguíneo Regional/efeitos dos fármacos , Agonistas do Receptor de Serotonina/administração & dosagem , Triazóis/administração & dosagem , Adulto , Córtex Cerebral/fisiologia , Feminino , Lateralidade Funcional , Humanos , Fluxometria por Laser-Doppler/métodos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/fisiopatologia , Transtornos de Enxaqueca/tratamento farmacológico , Fatores de Tempo , Triptaminas
6.
J Clin Endocrinol Metab ; 90(7): 4133-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15811929

RESUMO

BACKGROUND: Conflicting data have been reported on the association between interferon (IFN)-beta therapy of multiple sclerosis (MS) patients and thyroid disease development. AIMS: The goals of this study are as follows: to assess the actual occurrence of thyroid dysfunction and autoimmunity during long-term IFN-beta therapy; to establish the possible presence of predictive factors for thyroid dysfunction development and duration; and to suggest an effective follow-up protocol for patients receiving long-term IFN-beta therapy. STUDY PROTOCOL: A total of 106 MS patients (76 women) underwent IFN-beta 1a or 1b therapy for up to 84 months (median, 42 months). Thyroid function and autoimmunity were assessed at baseline and every 3-6 months throughout the treatment course. RESULTS: Baseline thyroid autoimmunity was detected in 8.5% of patients and hypothyroidism in 2.8%. Thyroid dysfunction (80% hypothyroidism, 92% subclinical, 56% transient) developed in 24% (68% with autoimmunity) of patients and autoimmunity in 22.7% (45.5% with dysfunction), without significant differences between the two cytokines; 68% of dysfunctions occurred within the first year. Autoimmunity emerged as the only predictive factor for dysfunction development (relative risk, 8.9), whereas sustained disease was significantly associated with male gender (P < 0.003). CONCLUSIONS: Both incident thyroid autoimmunity and dysfunction frequently occur in MS patients during IFN-beta therapy, particularly within the first year of treatment. Thyroid dysfunction is generally subclinical and transient in over than half of cases; preexisting or incident autoimmunity emerged as the only significant predictive factor for thyroid dysfunction development. Thyroid function and autoimmunity assessment is mandatory within the first year of IFN-beta therapy; thereafter, serum TSH measurement only in patients with thyroid disease could be sufficient.


Assuntos
Interferon beta/efeitos adversos , Esclerose Múltipla/tratamento farmacológico , Doenças da Glândula Tireoide/etiologia , Adulto , Autoimunidade , Feminino , Seguimentos , Humanos , Interferon beta-1a , Interferon beta-1b , Masculino , Pessoa de Meia-Idade , Glândula Tireoide/imunologia , Fatores de Tempo
7.
Eur J Haematol ; 72(6): 437-40, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15128423

RESUMO

Sequencing of alpha-globin genes of 18 Sardinian heterozygotes for the Hb G-Philadelphia [alpha 68(E17)Asn-->Lys] variant, with four active alpha genes and circulating level of the variant of about 27%, showed the AAC-->AAG change at codon 68 of the alpha 2-globin gene (alpha(G)alpha/alpha alpha). Two heterozygotes with level of about 37% were the carriers of the same mutation on the same alpha 2 gene, and of the alpha 2 alpha 1 hybrid gene, because of the 3.7-kb deletion, in trans (alpha(G)alpha/-alpha(3.7)). In Black people, the same C-->G mutation occurs on the hybrid gene (-alpha(G)3.7), whereas in Caucasians the Lys for Asn change is because of the C-->A transversion occurring on the alpha 2 gene of a normal alpha alpha arrangement. The identification of the C-->G mutation on the normal alpha alpha chromosome points to an undescribed genotype for this rather common variant, which is probably because of the high rate of recombination between the duplicated alpha-globin genes.


Assuntos
Genes Duplicados , Globinas/genética , Hemoglobinas Anormais/genética , Mutação Puntual , Adulto , Criança , Cromossomos , Análise Mutacional de DNA , Feminino , Variação Genética , Heterozigoto , Humanos , Itália/epidemiologia , Masculino , Recombinação Genética , Deleção de Sequência
8.
Int J Clin Pharmacol Ther ; 40(7): 304-9, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12139207

RESUMO

OBJECTIVE: To assess the residual effects of lormetazepam on daytime vigilance, psychomotor performance and simulated driving in adult healthy volunteers. MATERIAL: Twelve subjects (7 women, 5 men), aged 27 - 38 years (mean 31). METHOD: Subjects received lormetazepam 1 mg tablet and placebo for 3 days at nighttime in a randomized, double-blind, crossover design, with a 1-week interval between medications. On the morning following the last drug administration, the subjects completed a 15-min battery of neuropsychological tests aimed at assessing memory and attention, performed simple and choice visual reaction times, and self-rated their own level of sleepiness using the Epworth sleepiness scale. Afterwards, an interactive, computer-based driving simulator (STISIM) was used to assess the effect of the study drugs on driving ability, followed by the multiple sleep latency test (MSLT). RESULTS: The findings showed that participants had similar performance when treated with lormetazepam and placebo. Indeed, as compared with baseline, neuropsychological tests, visual reaction times, sleep latency using the MSLT and driving ability showed no deterioration following either placebo or active medication. CONCLUSIONS: The data suggest that 3-day use of lormetazepam 1 mg/day neither influences daytime vigilance nor impairs psychomotor task performance and simulated driving. Results confirm previous evidence that the intermediate-acting hypnotic benzodiazepine lormetazepam is devoid of residual effects in respect to psychomotor ability. However, caution should be exercised in the interpretation of the results due to the limited sensitivity of the study.


Assuntos
Ansiolíticos/efeitos adversos , Condução de Veículo/psicologia , Benzodiazepinas , Lorazepam/análogos & derivados , Lorazepam/efeitos adversos , Desempenho Psicomotor/efeitos dos fármacos , Sono/efeitos dos fármacos , Adulto , Ansiolíticos/administração & dosagem , Simulação por Computador , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Lorazepam/administração & dosagem , Masculino , Fases do Sono/efeitos dos fármacos
10.
Eur J Biochem ; 268(11): 3313-20, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11389734

RESUMO

A study was made of the haemoglobin (Hb) system from the Sardinian dwarf horse (Equus caballus jara), one of the last surviving wild horse species in Europe. The oxygen binding properties of the whole haemolysate and of the four different horse Hbs, separated by ion-exchange chromatography, were studied with special regard to the effect of chloride, 2,3-diphosphoglycerate and lactate. Results indicate that no significant functional differences exist between the four Hb components of horse haemolysate. Moreover, the molecular basis of the intrinsically low oxygen affinity and of the weak interaction of horse Hb with 2,3-diphosphoglycerate is discussed in the light of the primary structure of the molecule and of the results of a computer modelling approach. On these bases, it is suggested that the A1 (Thr-->Ser) and A2 (Pro-->Gly) substitutions observed in the beta chains from horse Hb may be responsible for the displacement of the A helix that is known to be a key structural feature of those Hbs that display an altered interaction with 2,3-diphosphoglycerate as compared with human Hb.


Assuntos
Hemoglobinas/genética , Cavalos/genética , Adulto , Animais , Sítios de Ligação , Proteínas de Transporte/química , Simulação por Computador , Eritrócitos/química , Haplótipos , Hemoglobinas/isolamento & purificação , Cavalos/sangue , Humanos , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Modelos Moleculares , Proteínas do Tecido Nervoso/química , Fenótipo
11.
Hemoglobin ; 24(1): 37-44, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10722114

RESUMO

Hb F-Calabria [Ggamma118(GH1)Phe-->Leu] is a new fetal hemoglobin variant that was found during routine screening for abnormal hemoglobins in a newborn of Calabrian (Southern Italy) ancestry. The variant chain was identified (acid urea gel electrophoresis of dissociated globin chains in the presence of Triton X-100, and by reversed phase high performance liquid chromatography) as a slightly hydrophilic Ggamma chain. Sequencing of the polymerase chain reaction-amplified exon 3 of the Ggamma-globin gene demonstrated the TTC-->CTC mutation at codon 118 leading to the Phe-->Leu conservative substitution at position GH1. A molecular modeling study supports that the variant might not have clinical implications. This is the 40th example of a Ggamma chain variant.


Assuntos
Hemoglobina Fetal/química , Hemoglobina Fetal/genética , Hemoglobinas Anormais/química , Hemoglobinas Anormais/genética , Substituição de Aminoácidos , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Éxons , Variação Genética , Globinas/química , Globinas/genética , Humanos , Recém-Nascido , Itália/epidemiologia , Itália/etnologia , Modelos Moleculares , Triagem Neonatal , Octoxinol/farmacologia , Mutação Puntual , Análise de Sequência de DNA , Ureia/farmacologia
13.
Biochem J ; 346 Pt 1: 193-9, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10657257

RESUMO

Haemoglobin (Hb) J-Sardegna [alpha50(CE8)His-->Asp] is a haemoglobin variant characteristic of subjects from the island of Sardinia. Here we report a study of the functional properties of both fetal and adult Hb J-Sardegna. The results indicate that adult Hb J-Sardegna displays an oxygen affinity that is higher than that of adult Hb only in the presence of 2,3-diphosphoglycerate (2,3-DPG). On the contrary, at 20 degrees C, the oxygen affinity of fetal Hb J-Sardegna is identical to that of normal fetal haemoglobin, both in the presence and in the absence of 2,3-DPG. A significant difference between these two systems (i.e. a higher oxygen affinity of fetal Hb J-Sardegna) shows up very clearly only when temperature is increased to 37 degrees C. Hence in fetal Hb, the main effect of the amino acid substitution is a decrease in the overall enthalpy change of oxygenation. The results outline the role of the alpha(1)-beta(1) interface in assessing the thermodynamics of oxygen binding. The functional properties of both adult and fetal Hb J-Sardegna have been interpreted at the structural level in light of the results obtained by a computational modelling approach performed in comparison with HbA and Hb Aichi, a variant characterized by a different mutation [alpha50(CE8)His-->Arg] at the same position.


Assuntos
Envelhecimento/sangue , Substituição de Aminoácidos/genética , Sangue Fetal/química , Hemoglobina J/química , Hemoglobina J/metabolismo , Modelos Moleculares , 2,3-Difosfoglicerato/metabolismo , Adulto , Arginina/genética , Ácido Aspártico/genética , Sítios de Ligação , Simulação por Computador , Cristalografia por Raios X , Variação Genética/genética , Hemoglobina J/genética , Hemoglobinas Anormais/química , Hemoglobinas Anormais/genética , Hemoglobinas Anormais/metabolismo , Histidina/genética , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido , Oxigênio/metabolismo , Temperatura , Termodinâmica , Fatores de Tempo
14.
Minerva Ginecol ; 51(11): 437-43, 1999 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-10726443

RESUMO

BACKGROUND: In this study the results of six years experience (1993-1998) in IVF, ICSI and assisted hatching on 442 sterile couples for a total of 868 cycles are reported. Since 1997 ICSI has also been carried out in cases of azoospermia extracting mobile spermatozoa from the epididymal (MESA) or from the testicle (TESE). METHODS: Ages ranged from 20 to 48 and mean years sterility was 5.868 cycles were carried out of which 153 (17.62%) were for IVF, 705 (81.22%) for ICSI and 10 (1.15%) for MESA and TESE. Assisted hatching was performed through "partial zona dissection" in 329 cases on a total of 987 embryos. RESULTS: The pregnancy rates per embryo transfer in IVF and ICSI cycles were 22.4 and 19.96% respectively. Results considering patients age were: 33.87% below 35, 29.55% between 35 and 38 and 6.60% above 38. In the group of 189 assisted hatching patients the evolutive pregnancy rate rose from 15.78 to 26.40% and multiple pregnancies from 28.63 to 42%. CONCLUSIONS: ICSI has offered high rates of fertilization and pregnancy even in extreme cases of oligoasthenospermia or cases of azoospermia adopting MESA or TESE techniques. A decisive factor on pregnancy rates is age, very low over 38 years. Assisted Hatching further increased the pregnancy rates.


Assuntos
Fertilização in vitro , Injeções de Esperma Intracitoplásmicas , Adulto , Transferência Embrionária/métodos , Transferência Embrionária/estatística & dados numéricos , Feminino , Fertilização in vitro/métodos , Fertilização in vitro/estatística & dados numéricos , Hospitais Especializados , Humanos , Infertilidade/terapia , Itália , Masculino , Pessoa de Meia-Idade , Gravidez , Técnicas Reprodutivas , Injeções de Esperma Intracitoplásmicas/métodos , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos
16.
J Clin Endocrinol Metab ; 82(10): 3315-8, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9329360

RESUMO

Alterations in muscle structure and function have been reported in overt hypothyroidism, with decreased activity of enzymes involved in anaerobic and oxidative glucose metabolism. To test whether similar changes in muscle energy metabolism are present in subclinical hypothyroidism (sHT), we studied 12 patients with sHT who complained of mild neuromuscular symptoms. The control group included 10 sex- and age-matched healthy volunteers. Skeletal muscle lactate and pyruvate production were determined in the resting state and during dynamic arm exercise. During exercise, blood lactate was significantly higher in sHT patients than in controls from the third exercise step onward (P = 0.02 at 30%, p = 0.008 at 40%, and P = 0.002 at 50% of maximal voluntary contraction). Moreover, the mean increment in blood lactate during exercise was positively related (r2 = 0.44; P = 0.02) to the duration of sHT, but not to serum levels of TSH, free T3, or free T4. No significant difference was found in blood pyruvate concentrations between the two groups at baseline or during exercise. Thus, the lactate/pyruvate ratio curve paralleled the lactate curve in patients as well as controls. We conclude that muscle energy metabolism is impaired in sHT in rough proportion to the known duration of the disease. Early L-T4 therapy may be useful not only to provide specific treatment for such metabolic changes, but also to avoid progression to frank hypothyroidism.


Assuntos
Hipotireoidismo/metabolismo , Hipotireoidismo/fisiopatologia , Músculos/metabolismo , Músculos/fisiopatologia , Adolescente , Adulto , Metabolismo Energético , Exercício Físico , Feminino , Humanos , Lactatos/sangue , Masculino , Piruvatos/sangue , Valores de Referência , Hormônios Tireóideos/sangue
17.
Comp Biochem Physiol B Biochem Mol Biol ; 117(3): 417-20, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9253179

RESUMO

The functional properties of Hb B of the wild European mouflon (Ovis gmelini musimon), Hb B of domestic sheep (Ovis aries), and Hb C isolated from anemic mouflon were investigated. Mouflon and sheep Hbs appear to be very similar in their response to organic anions and protons, whereas sheep Hb B displays an oxygen affinity lower than that of mouflon Hb B and sheep Hb A. Mouflon Hb B and Hb C, like sheep Hb A and Hb C, have similar efficiencies in transporting oxygen to the tissues. As in other ruminant Hbs, the effect of temperature on the oxygen affinity is slight. Data suggest that mouflon Hb B is not only structurally, but even functionally, more similar to sheep Hb A than to sheep Hb B.


Assuntos
Hemoglobina A/metabolismo , Hemoglobina C/metabolismo , Hemoglobinas/metabolismo , Ovinos/sangue , Animais , Concentração de Íons de Hidrogênio , Oxiemoglobinas/metabolismo , Fenótipo , Temperatura , Termodinâmica
18.
Eur J Haematol ; 58(5): 320-5, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9222287

RESUMO

The -175 (T-->C) G gamma hereditary persistence of fetal haemoglobin is a very rare promoter mutation occurring in Caucasians as well as in African-Americans. Heterozygotes for this non-deletional HPFH show 20% HbF, mostly of G gamma type. We describe here a healthy Sardinian man who coinherited -175 (T-->C) G gamma HPFH with the beta-thalassaemia codon 39 nonsense mutation in trans; he showed 64% HbF, 100% of G gamma type. Although the beta-globin haplotype pattern (II/II) was indicative of the presence of the A gamma T allele on both chromosomes, the A gamma T expression was undetectable by HPLC even in red cell populations separated by age. The proband was, moreover, homozygous for the -4 bp deletion at position -225 to -222 of A gamma promoter which has recently been associated with decreased A gamma T globin expression. These findings suggest that this maximal overexpression of G gamma-globin probably reflects intensified stimulation of the mutated G gamma promoter in this hitherto undescribed genetic condition.


Assuntos
Hemoglobina Fetal/genética , Hemoglobinopatias/genética , Talassemia beta/genética , gama-Globulinas/genética , Adulto , Saúde da Família , Hemoglobina Fetal/química , Expressão Gênica , Heterozigoto , Humanos , Itália/epidemiologia , Masculino , Mutação , Prevalência , Talassemia beta/epidemiologia , gama-Globulinas/química
19.
Ital J Biochem ; 46(1): 7-14, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9247845

RESUMO

A study was made of the Hb phenotype of the Sardinian dwarfhorse (Equus caballus jara), one of the last surviving wild horse species in Europe. Hb haplotypes and their frequencies were found to be similar to those described in the Arabian horse (BI = 0.551, BII = 0.389, A = 0.036, V = 0.015), which suggests possible introduction onto the island from North Africa. The oxygen binding properties of the whole hemolysates and of the four different horse Hbs, separated by ion-exchange chromatography, were considered with regard to the effect of chloride, 2,3-bisphosphoglycerate and lactate. Results indicate that no differences exist in the four components that characterize horse Hb. The molecular basis of the intrinsically low oxygen affinity and of the weak interaction of horse Hb with 2,3-bisphosphoglycerate is discussed in the light of the primary structure of the molecule.


Assuntos
Hemoglobinas/genética , Cavalos/genética , Oxigênio/sangue , Polimorfismo Genético , Animais , Nanismo/genética , Frequência do Gene , Haplótipos , Hemólise , Humanos , Itália , Modelos Lineares , Fenótipo , Ligação Proteica , Especificidade da Espécie
20.
Muscle Nerve ; 19(3): 342-9, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8606699

RESUMO

The data from histological, biochemical, and mitochondrial DNA (mtDNA ) studies of muscle biopsies from 10 patients affected with chronic progressive external ophthalmoplegia (CPEO) were related to dynamic and metabolic parameters of incremental submaximal exercise. Maximum power output was reduced in all patients as compared to controls. Analysis of the venous lactate curve during exercise revealed a lactate threshold at exercise levels ranging from 40 to 50% of the predicted maximal power output. An earlier significant increase in lactate could be detected by calculating the mean delta lactate. Lactate values were inversely correlated with the cytochrome c oxidase (COX) activity of isolated muscle mitochondria. No relationship was found between lactate values and the number of ragged red fibers, or cytochrome c oxidase-negative fibers of the proportion of deleted mtDNA measured in muscle biopsy specimens. The discussion underscores the value of lactate kinetics in assessing skeletal muscle function, as well as the use of muscle COX levels to predict the effectiveness of wild-type complementation of deleted skeletal muscle mtDNA in in vivo contractile performance of CPEO subjects.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Lactatos/metabolismo , Músculo Esquelético/enzimologia , Oftalmoplegia Externa Progressiva Crônica/enzimologia , Esforço Físico/fisiologia , Adulto , Idoso , DNA Mitocondrial/genética , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Mutação/fisiologia , Oftalmoplegia Externa Progressiva Crônica/genética , Oftalmoplegia Externa Progressiva Crônica/fisiopatologia , Piruvatos/metabolismo
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