RESUMO
Hereditary persistence of fetal haemoglobin (HPFH) is the major modifier of the clinical severity of ß-thalassaemia. The homozygous mutation c.-196 C>T in the Aγ-globin (HBG1) promoter, which causes Sardinian δß0 -thalassaemia, is able to completely rescue the ß-major thalassaemia phenotype caused by the ß0 39-thalassaemia mutation, ensuring high levels of fetal haemoglobin synthesis during adulthood. Here, we describe a CRISPR/Cas9 genome-editing approach, combined with the non-homologous end joining (NHEJ) pathway repair, aimed at reproducing the effects of this naturally occurring HPFH mutation in both HBG promoters. After selecting the most efficient guide RNA in K562 cells, we edited the HBG promoters in human umbilical cord blood-derived erythroid progenitor 2 cells (HUDEP-2) and in haematopoietic stem and progenitor cells (HSPCs) from ß0 -thalassaemia patients to assess the therapeutic potential of HbF induction. Our results indicate that small deletions targeting the -196-promoter region restore high levels of fetal haemoglobin (HbF) synthesis in all cell types tested. In pools of HSPCs derived from homozygous ß0 39-thalassaemia patients, a 20% editing determined a parallel 20% increase of HbF compared to unedited pools. These results suggest that editing the region of HBG promoters around the -196 position has the potential to induce therapeutic levels of HbF in patients with most types of ß-thalassaemia irrespective of the ß-globin gene (HBB) mutations.
Assuntos
Hemoglobina Fetal/genética , Edição de Genes/métodos , Células-Tronco Hematopoéticas/metabolismo , Talassemia beta/genética , Sistemas CRISPR-Cas , Células Cultivadas , Células HEK293 , Humanos , Células K562 , Regulação para CimaRESUMO
The development of compact accelerator facilities providing high-brightness beams is one of the most challenging tasks in the field of next-generation compact and cost affordable particle accelerators, to be used in many fields for industrial, medical, and research applications. The ability to shape the beam longitudinal phase space, in particular, plays a key role in achieving high-peak brightness. Here we present a new approach that allows us to tune the longitudinal phase space of a high-brightness beam by means of plasma wakefields. The electron beam passing through the plasma drives large wakefields that are used to manipulate the time-energy correlation of particles along the beam itself. We experimentally demonstrate that such a solution is highly tunable by simply adjusting the density of the plasma and can be used to imprint or remove any correlation onto the beam. This is a fundamental requirement when dealing with largely time-energy correlated beams coming from future plasma accelerators.
RESUMO
Plasma-based technology promises a tremendous reduction in size of accelerators used for research, medical, and industrial applications, making it possible to develop tabletop machines accessible for a broader scientific community. By overcoming current limits of conventional accelerators and pushing particles to larger and larger energies, the availability of strong and tunable focusing optics is mandatory also because plasma-accelerated beams usually have large angular divergences. In this regard, active-plasma lenses represent a compact and affordable tool to generate radially symmetric magnetic fields several orders of magnitude larger than conventional quadrupoles and solenoids. However, it has been recently proved that the focusing can be highly nonlinear and induce a dramatic emittance growth. Here, we present experimental results showing how these nonlinearities can be minimized and lensing improved. These achievements represent a major breakthrough toward the miniaturization of next-generation focusing devices.
RESUMO
OBJECTIVE: During climacteric the reduction or interruption of estrogenic stimulus determines a gradual atrophy of the tissues of the urogenital tract.Vulvovaginal atrophy can be cause of dryness, itch, burning, and dyspareunia. Vulvovaginal atrophy is associated also with depression. Hence the importance of an appropriate treatment of the vulvovaginal atrophy. Between therapeutic options we can add, particularly for women who suffer only from vaginal symptoms, the spa therapy that uses mineral waters with benefic effects on vaginal tissue wellness and health. On the basis of considerations described above and on the insufficient literature data, the objective of our single-arm pilot study has been to evaluate, in women suffering from vulvovaginal atrophy, the effects and safety of a vaginal douching cycle with sulphurous mineral water and impact on depression disorder frequently observed. PATIENTS AND METHODS: The study was conducted on 24 women affected by vulvovaginal atrophy; mean age:57±11 years; age range:42-81 years. The subjects were treated, for 2 weeks, with sulphurous vaginal douching from Terme of Telese S.p.A. (Benevento-Italy). At the beginning and at the end of the SPA treatment the following symptoms were evaluated: dryness, burning, itch, dyspareunia and leucorrhoea (using VAS scale); the impact on psychological distress (using S.D.S. Zung-test). RESULT: At the end of the spa treatment, the mean values±SD, compared to baseline, have showed a significant (p<0.05) reduction in leucorrhoea (-88%), in vulvar itch (-79%), in vaginal burning (-71%), in vaginal dryness (-65%) with an improvement of psichological distress as demonstrated by S.D.S. Zung-test. CONCLUSION: The data of this single-arm pilot clinical trial show that the sulphurous vaginal douching cycle can be considered very useful in women suffering from vulvovaginal atrophy with improving of the quality of life and social relationship.
Assuntos
Doenças Vaginais/terapia , Ducha Vaginal , Vulva/patologia , Doenças da Vulva/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Atrofia , Dispareunia/etiologia , Dispareunia/terapia , Feminino , Humanos , Itália , Pessoa de Meia-Idade , Águas Minerais/uso terapêutico , Projetos Piloto , Pós-Menopausa , Qualidade de Vida , Enxofre/uso terapêutico , Doenças Vaginais/patologia , Ducha Vaginal/efeitos adversos , Doenças da Vulva/patologiaRESUMO
Os acromiale consist in a lack of fusion between the different ossification spots of the acromial side of scapula from the age of 23-25 years. A relation between os acromiale and some shoulder pathology like impingement syndrome, cuff tear and subacromial bursitis has been described. The etiology is not already known. The aim of this study was to evaluate the frequency of os acromiale in our population, the link between os acromiale and sex, side and shoulder pathology. 1042 shoulder MRI were evaluated to find out os acromiale and the linked cuff pathology. In our population, the frequency of os acromiale was 3.44% without differences between sexes, with prevalence on the right shoulder. No differences in cuff and bursa pathology were present between affected and unaffected subjects. Os acromiale is an anomaly still underdiagnosed. It is important to be recognized because it allows to make an accurate pre-surgical plan. To make a correct diagnosis, axial MRI cut or TC is necessary.
Assuntos
Acrômio/patologia , Imageamento por Ressonância Magnética , Acrômio/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Bursite/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteogênese , Prevalência , Lesões do Manguito Rotador/etiologia , Síndrome de Colisão do Ombro/etiologia , Articulação do Ombro/diagnóstico por imagemRESUMO
This work investigates life-history traits of the long-nosed skate Dipturus oxyrinchus, which is a common by-catch in Sardinian waters. The reproductive variables were analysed from 979 specimens sampled during scientific and commercial hauls. Females (10·4-117·5 cm total length, LT ) attained larger sizes than males (14·5-99·5 cm LT ). To evaluate age and growth, a sub-sample of 130 individuals (76 females and 54 males) were used. The age was estimated by annuli counts of sectioned vertebral centra. Four models were used for the length-at-age data: the von Bertalanffy, the exponential, the Gompertz and the logistic functions. According to the Akaike's information criterion, the Gompertz model seemed to provide the best fitting curve (L∞ mean ± s.e.: 127·55 ± 4·90 cm, k: 0·14 ± 0·09, IP: 3·97 ± 0·90 years). The oldest female and male were aged 17 (115·5 cm LT ) and 15 years (96·0 cm LT ), respectively. Lengths at maturity were 103·5 cm for females and 91·0 cm for males, corresponding to 90% of the maximum observed length in both sexes. The monthly distribution of maturity stages highlighted an extended reproductive cycle, with spawning females and active males being present almost throughout the year, as confirmed by the gonado-somatic index. Ovarian fecundity reached a maximum of 26 yolked follicles with a mean ± s.e. size of 19·7 ± 6·5 mm.
Assuntos
Reprodução , Maturidade Sexual , Rajidae/crescimento & desenvolvimento , Determinação da Idade pelo Esqueleto , Distribuição Animal , Migração Animal , Animais , Tamanho Corporal , Feminino , Fertilidade , Itália , Características de História de Vida , Masculino , Modelos Biológicos , Coluna Vertebral/crescimento & desenvolvimentoRESUMO
BACKGROUND AND OBJECTIVE: The chronic arthropathies currently appear to be a major cause of disability with a negative impact on quality of life and health care spending. The mud-bath therapy is a spa treatment that induces benefic effects in chronic rheumatic diseases. It has long been debated on the assumption that the mud-bath spa therapy could have adverse cardiovascular effects which often induce caution and even a contraindication to the use of this treatment in chronic arthropathies associated with cardiovascular alterations such as hypertension. The aim of this observational study was to investigate, in arthrorheumatic subjects, the effects of sulphureous mud-bath cycle on blood pressure and the possible appearance of adverse drug reaction. PATIENTS AND METHODS: 169 patients, with age range 42-86 years, suffering by chronic arthropathies were treated with sulphureous mud-bath therapy for 2 weeks. According to the arterial pressure values, measured before the spa treatment, the patients considered were divided in three groups: with normal blood pressure (NOR group); with high blood pressure, after, the latter group was divided in IPET (patients in treatment with antihypertensive drugs) and IPENT (patients not in antihypertensive therapy). The arterial pressure values, maximum and minimum, expressed in mmHg, were detected in the first (T1) - sixth (T6) and twelfth (T12) day of spa treatment. The media arterial pressure values collected before and after T1, before and after T6, before and after T12 , before T1 and after T12 were compared. The data, presented as mean±SD, were compared with the paired Student t test. A p value ≤0.05 was considered significant. RESULTS: The comparison between the mean values detected in pre and post T1, pre and post T6, pre and post T12 have showed that sulphureous mud-bath therapy induced a significant (p<0.05) reduction of arterial blood pressure values in patients suffering of chronic arthropathies with high blood pressure in antihypertensive therapy or not (IPET and IPENT groups); while in patients with normal blood pressure (NOR group) were observed modest reduction at the limit of statistical significance. Similarly, the comparison between the data detected at the end of sulphureous mud-bath therapy (post-T12) vs baseline (pre-T1) have demonstrated: in IPET and IPENT groups a significant (p<0,01) decrease of arterial blood pressure values; in NOR group very small decrease, this reduction is significant (p<0.05) only for maximum arterial pressure value. Were not observed adverse drug reaction. CONCLUSIONS: The results of our study, in according with the few data in the literature, evidenced that is possible include the sulphureous mud-bath therapy in interdisciplinary therapeutic p rotocol of patients suffering of chronic arthropathies and arterial hypertension.
Assuntos
Pressão Sanguínea , Hipertensão/terapia , Peloterapia/métodos , Doenças Reumáticas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Determinação da Pressão Arterial , Doença Crônica , Feminino , Humanos , Hipertensão/complicações , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doenças Reumáticas/complicações , Doenças Reumáticas/fisiopatologia , Compostos de Enxofre/uso terapêutico , Resultado do TratamentoRESUMO
A total of 255 longnosed skate Dipturus oxyrinchus caught in Sardinian waters (central-western Mediterranean Sea), was analysed with respect to fish total length (LT ), season and depth, in order to provide information on diet and feeding behaviour. Specimens ranging from 93 to 1153 mm LT , were collected at depths between 121 and 671 m, during experimental trawl surveys carried out from 2005 to 2010. The diet comprised crustaceans [prey specific index of relative importance (%IPSRI ) = 72·69], teleosts (%IPSRI = 10·28) and molluscs (%IPSRI = 10·94). Levins' index (Bi ) showed a narrow niche breadth (Bi = 0·35). The mean ± s.e. trophic level (TL ) was 3·63 ± 0·50. The analysis showed major ontogenetic changes in the feeding behaviour. Early life stages were characterized by a benthic diet, which changed to benthopelagic during growth. Mysids, particularly Lophogaster typicus (%IPSRI = 34·51), were the main prey items of immature individuals, replaced by euphausiids, mainly Meganyctiphanes norvegica (%IPSRI = 13·19), in maturing fish. Crustaceans became less important in mature specimens, being replaced by molluscs (%IPSRI = 28·99) and teleosts (%IPSRI = 24·56). A concomitant increase of the TL was recorded (mean ± s.e. = 3·41 ± 0·44, 3·75 ± 0·54 and 4·28 ± 0·61 for immature, maturing and mature individuals). These feeding patterns ensured low levels of intraspecific competition. This study provides new information about the role that the D. oxyrinchus plays in the marine food chain and data now essential to formulate new and effective management plans for this species.
Assuntos
Dieta , Comportamento Alimentar , Rajidae/fisiologia , Animais , Cadeia Alimentar , Conteúdo Gastrointestinal , Mar Mediterrâneo , Estações do AnoRESUMO
Purpose of this study is to evaluate the effectiveness of muscle transfer of the teres major in the treatment of irreparable posterosuperior injuries of the rotator cuff. Long-term monitoring of the results obtained in 20 patients treated at our clinic using this method are reported, comparing the data obtained in evaluations of results with preoperative values. Clinical evaluations were obtained using the Constant Score System, while X-ray examination showed the presence of osteoarticular modifications, and MRI and electromyography the preserved morphology and function of transplant. The mean Constant Score increased from 31.6 points preoperatively to 66.1 points postoperatively at the time of follow-up. At follow-up, MRI allowed us to evaluate any fatty degeneration of the muscle fibers of transfer and the integrity of tendinous insertion on the humeral greater tuberosity. The obtained results allowed us to reveal the advantages and the disadvantages of teres major transplant in irreparable posterosuperior ruptures of the cuff.
Assuntos
Músculo Esquelético/transplante , Lesões do Manguito Rotador , Manguito Rotador/cirurgia , Adulto , Idoso , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Manguito Rotador/diagnóstico por imagem , Ruptura , Lesões do Ombro , Articulação do Ombro/cirurgiaRESUMO
A series of 6-aryl-2,4-dioxo-5-hexenoic acids, were synthesized and tested against HIV-1 in cell-based assays and against recombinant HIV-1 integrase (rIN) in enzyme assays. Compound 8a showed potent antiretroviral activity (EC(50)=1.5 microM) and significant inhibition against rIN (strand transfer: IC(50)=7.9 microM; 3'-processing: IC(50)=7.0 microM). A preliminary molecular modeling study was carried out to compare the spatial conformation of 8a with those of L-731988 (4) and 5CITEP (7) in the IN core.
Assuntos
Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Inibidores de Integrase de HIV/química , Inibidores de Integrase de HIV/farmacologia , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , Replicação Viral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , HIV-1/fisiologiaRESUMO
Despite the unprecedented successes in the therapy of HIV infection, AIDS remains a major world health problem being the first cause of death in Africa and the fourth leading cause of death worldwide. Rapid emergence of drug-resistant HIV variants and severe side effects limit the efficacy of existing therapies. The intrinsic high variability of HIV calls for combining different drugs with distinct mode of action to achieve synergistic antiviral activity. Efforts are being made to develop agents addressing new steps in HIV replication and to optimize both antiviral activity and pharmacokinetic of the current drugs targeting reverse transcriptase and protease. The class of viral entry inhibitors is undergoing evaluation for both systemic and topical administration, and compounds targeting the fusion step may be the first to reach the market. Identification of compounds unambiguously affecting HIV replication by targeting integrase supports the potential of this crucial viral enzyme as a drug target. Targeting HIV gene regulation, which could also lead to cellular toxicity, may also become an important discovery strategy, provided that inhibitors with sufficient specificity are identified. In this review we will summarize the current understanding of the key steps in HIV life cycle in the context of representative inhibitors based on their modes of action. We then present a summary of compounds under clinical development, with the aim of providing a picture of the current potential for targeting HIV.
Assuntos
Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV/efeitos dos fármacos , Terapia Antirretroviral de Alta Atividade , Proteínas do Capsídeo/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/virologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Infecções por HIV/prevenção & controle , Infecções por HIV/virologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Humanos , Receptores Virais/efeitos dos fármacos , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêuticoRESUMO
Worldwide, the heterosexual route is the prevalent mode of transmission of AIDS; therefore, demands have been raised for measures that block sexual spreading of the HIV infection. Development of microbicides for topical use may represent an efficacious alternative to condoms. Several approaches are being investigated. Besides surfactants, which directly act on the virus particle, and measures that enhance natural defence mechanisms, promising new candidates appear to be drugs that block the early steps of HIV multiplication. We describe herein a long-term assay which enables the establishment of whether the above drugs reversibly (virustatic action) or irreversibly (virucidal action) inhibit HIV-1 multiplication, thus allowing screening for effective and potent microbicides. We validated our assay with nucleoside (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs). Following a chronic treatment, the NRTIs tested (didanosine, zalcitabine, stavudine and lamivudine) simply delayed the viral breakthrough with respect to infected, untreated controls. Under the same experimental conditions, non-nucleoside reveres transcriptase inhibitors (NNRTIs), such as MKC-442, alphaAPA, nevirapine, efavirenz and 3,4-dihydro-2-alkoxy-6-benzyl-4-oxopyrimidines (DABOs) MC 1047 and MC 1220 suppressed HIV-1 replication for the entire experimental period (40 days). When cell culture samples were evaluated for the presence of infectious virus, p24 antigen and viral DNA sequences, none of them was detected up to day 40 post-infection (p.i.). Identical results were obtained after a treatment with the above NNRTIs limited to the first 4 days p.i. Under more selective experimental conditions, that is drug treatments limited to the first 4 h p.i., nevirapine and efavirenz proved to be virustatic; in fact, viral breakthrough ensued shortly after their removal from the culture medium. Conversely, DABO MC 1220 was endowed with potent virucidal activity; in fact, at 3.5 microM it was able to suppress HIV-1 multiplication in cultures acutely infected with a very high multiplicity of infection (5 CCID50/cell), thus allowing exponential cell multiplication as in uninfected cultures for the next 40 days.
Assuntos
Fármacos Anti-HIV/farmacologia , Infecções por HIV/prevenção & controle , Mucosa/virologia , Pirimidinas/farmacologia , Inibidores da Transcriptase Reversa/farmacologia , Linhagem Celular , DNA Viral/análise , Infecções por HIV/transmissão , HIV-1/efeitos dos fármacos , HIV-1/genética , HIV-1/fisiologia , Humanos , Técnicas In Vitro , Replicação Viral/efeitos dos fármacosRESUMO
Several 5-alkyl, 5-alkenyl, 5-iso-alkyl, 5-halo, 5-aminomethyl and 5-carboxy derivatives of S-DABOs (dihydro-alkyl (or cyclo-alkyl)thio-benzyloxopyrimidines), DATNOs (dihydro-alkylthionaphthylmethyl-oxopyrimidines) and F2-S-DABOs (dihydro-alkyl (or cyclo-alkyl)thio-2,6-difluorobenzyl-oxopyrimidines) have been prepared and tested as anti-HIV-1 agents. S-DABO derivatives bearing at C-6 position monosubstituted phenylmethyl or heteroarylmethyl units have also been synthesized. 2-Alkylthio-3,4-dihydropyrimidin-4(3H)-one derivatives of F2-S-DABO series bearing small alkyl groups at C-5 proved to be potent inhibitors of HIV-1 replication in vitro with selectivity indexes ranging from 250 to >2,500.
Assuntos
Fármacos Anti-HIV/química , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Pirimidinonas/química , Inibidores da Transcriptase Reversa/química , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/toxicidade , Linhagem Celular , Fenômenos Químicos , Físico-Química , Desenho de Fármacos , HIV-1/fisiologia , HIV-2/fisiologia , Humanos , Estrutura Molecular , Pirimidinonas/síntese química , Pirimidinonas/farmacologia , Pirimidinonas/toxicidade , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/toxicidade , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacosRESUMO
A number of properly substituted 5H-pyrimido[4,5-b][1,5]benzodiazepines (2) and pyrazolo[3,4-b][1,5]benzodiazepines (3 and 4), as well as compounds 5-7, which are derivatives of new tetracyclic systems, were prepared as nevirapine analogues through multistep synthetic routes. The cytotoxic and anti-HIV-1 properties of compounds 2-7 were evaluated in cell-based assays, together with their inhibitory activity against the HIV-1 recombinant reverse transcriptase (rRT) in enzyme assays. The modifications introduced into nevirapine heterocyclic skeleton proved to have a negative effect for the anti-HIV-1 activity. It is worth noting that some of the new derivatives proved to be cytotoxic in the low micromolar range.
Assuntos
Benzodiazepinas/síntese química , HIV-1/efeitos dos fármacos , Nevirapina/síntese química , Inibidores da Transcriptase Reversa/síntese química , Linfócitos T/efeitos dos fármacos , Benzodiazepinas/química , Benzodiazepinas/farmacologia , Linhagem Celular , Transcriptase Reversa do HIV/antagonistas & inibidores , Humanos , Testes de Sensibilidade Microbiana , Nevirapina/análogos & derivados , Nevirapina/química , Nevirapina/farmacologia , Proteínas Recombinantes/antagonistas & inibidores , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologiaRESUMO
A number of new 3-(1-R-3(5)-methyl-4-nitroso-1H-5(3)-pyrazolyl)-5-methylisoxazoles 6a-g (7b-f) were synthesized and tested for antibacterial and antifungal activity. Some of these compounds displayed antifungal activity at non-cytotoxic concentrations. Derivative 6c was 9 times more potent in vitro than miconazole and 20 times more selective against C. neoformans. 6c was also 8- and 125-fold more potent than amphotericin B and fluconazole, respectively. None of the compounds was active against bacteria. Preliminary structure-activity relationship (SAR) studies showed that the NO group at position 4 of the pyrazole ring is essential for the activity. Lipophilicity of the pyrazole moiety, N-alkyl chain length and planarity of the two heterocyclic rings appear to play a decisive role in modulating cytotoxicity and antifungal activity.
Assuntos
Antifúngicos/síntese química , Antifúngicos/farmacologia , Isoxazóis/síntese química , Isoxazóis/farmacologia , Antibacterianos , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antifúngicos/química , Cryptococcus neoformans/efeitos dos fármacos , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Humanos , Isoxazóis/química , Testes de Sensibilidade Microbiana , Relação Estrutura-AtividadeRESUMO
Chemotherapy of HIV-1 infection/AIDS currently employs inhibitors of two products of the viral pol gene, the reverse transcriptase and protease enzymes. However, a third product of the pol gene is essential for retroviral multiplication, the integrase. As no cellular homologue of HIV integrase has been described, potential inhibitors could be relatively nontoxic. Development of HIV-1 integrase inhibitors could have favorable implication for combination therapy, including potential synergy with currently available inhibitors, as well as prevention of the chronic carrier state and the emergence of resistant mutants. Although several classes of putative integrase inhibitors that been described, still no clinically useful anti-integration drugs are available. It is the structural and functional complexity of the integration process together with the limitations of the available in vitro assays that has made it problematic to develop inhibitors of the HIV integrase. In this review we summarize current knowledge concerning the biology of this enzyme and of the integration process, and discuss major classes representatives of integrase inhibitors considering the obstacles to the development of true anti-integrase drugs.
Assuntos
Desenho de Fármacos , Inibidores de Integrase de HIV/farmacologia , Integrase de HIV/metabolismo , Animais , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Inibidores de Integrase de HIV/síntese química , Inibidores de Integrase de HIV/uso terapêutico , HIV-1/efeitos dos fármacos , HIV-1/enzimologia , HIV-1/ultraestrutura , HumanosRESUMO
Using 2,6-dichloro-4-aminopyrimidine, a number of uracil and cytosine derivatives with both arylthio and alkoxy moieties were prepared. These novel pyrimidines share chemical similarities with DABOs and HEPTs, two classes of non-nucleoside human immunodeficiency virus type 1 (HIV-1) reverse transcriptase inhibitors (NNRTIs), which have been widely studied of late. All new derivatives were tested in MT-4 cells to explore their potential in vivo anti-HIV activity. Like other NNRTIs, they selectively inhibit HIV-1 but not HIV-2. The majority of test derivatives were found to have low potency and were sometimes more cytotoxic than zidovudine and emivirine (formerly MKC-442), used here as reference drugs. Uracil and cytosine derivatives bearing a sec-butoxy chain and a methyl-substituted benzenesulphonyl moiety were the most potent. Enzyme assays proved that these derivatives target RT. Structure-activity relationship studies established a correlation between the anti-HIV-1 activity and the meta substitution on the phenyl ring; furthermore, oxidation of sulphide to sulphone significantly increased the potency of certain derivatives.
Assuntos
Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Testes de Sensibilidade Microbiana/métodos , Nucleosídeos/química , Pirimidinonas/química , Pirimidinonas/farmacologia , Relação Estrutura-Atividade , Sulfetos/química , Sulfetos/farmacologiaRESUMO
Due to the capability of peptidyl derivatives of araC to behave as prodrugs of this antimetabolite, and because of the well known biological properties of peptide T and its analogues (in particular that of targeting CD4+ cells), new peptide T-araC conjugates were prepared and tested in vitro for antiproliferative activity. The aim was that of specifically delivering the antitumor drug to CD4+ cells. N4-(Acylpeptidyl)-derivatives of araC were synthesized by a new general approach involving solid-phase synthesis, which allows mild conditions, avoids the usually required protection of the glycoside portion of nucleosides and affords high yields of the final products. After the demonstration that peptide T-araC conjugates were able to activate chemotaxis by binding CD4 receptor on monocyte membranes, the antiproliferative activity was evaluated against a panel of leukemia lymphoma and carcinoma cell lines derived from human tumors, three CD4+ cell lines included. Title compounds resulted effective as antiproliferative agents at concentrations 4- to 10-fold higher than those of araC alone, did not preferentially inhibit CD4+ cells and proved stable not only in cell culture medium containing 20% FCS, but also in human plasma. All this suggests their potential utility in vivo.
Assuntos
Citarabina/química , Citarabina/farmacologia , Peptídeo T/química , Peptídeo T/farmacologia , Antimetabólitos Antineoplásicos/química , Antimetabólitos Antineoplásicos/farmacologia , Antígenos CD4 , Divisão Celular/efeitos dos fármacos , Quimiotaxia/efeitos dos fármacos , Citarabina/síntese química , Relação Dose-Resposta a Droga , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Estabilidade de Medicamentos , Humanos , Concentração Inibidora 50 , Monócitos/efeitos dos fármacos , Oligopeptídeos/síntese química , Oligopeptídeos/metabolismo , Peptídeo Hidrolases/metabolismo , Peptídeo T/síntese química , Pró-Fármacos/síntese química , Pró-Fármacos/farmacologia , Fatores de Tempo , Células Tumorais Cultivadas/efeitos dos fármacosRESUMO
20 lactating ewes were allotted to two groups: 10 subjects received orally 100 mg/day of CdCl2 for 108 consecutive days, and the remaining 10 acted as control. Reproductive performance in ewes and cadmium tissue accumulation, both in ewes and their lambs, were investigated. The results showed that in ewes: 1) the regular cadmium intestinal intake negatively influences all reproductive parameters; 2) cadmium is particularly accumulated in kidney and liver, but also in mammary gland, although at a distinctly lower level; 3) chronic administration does not increase cadmium placental transfer in lactating pregnant subjects.
Assuntos
Cádmio/toxicidade , Lactação , Placenta/metabolismo , Reprodução/efeitos dos fármacos , Ovinos/fisiologia , Animais , Animais Recém-Nascidos/metabolismo , Peso ao Nascer/efeitos dos fármacos , Cádmio/administração & dosagem , Cádmio/metabolismo , Cádmio/farmacocinética , Feminino , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Glândulas Mamárias Animais/metabolismo , Placenta/efeitos dos fármacos , Circulação Placentária/efeitos dos fármacos , Gravidez , Ovinos/metabolismo , Poluentes do Solo/administração & dosagem , Poluentes do Solo/efeitos adversos , Poluentes do Solo/farmacocinética , Poluentes do Solo/toxicidade , Testes de ToxicidadeRESUMO
The promoter region of adult beta globin genes in humans and other mammals contains conserved regions of pivotal importance for their regulated tissue specific expression. These include the CACCC and CAAT motifs. The CACCC motif is duplicated in humans and other mammals. The human delta-globin gene lacks these conserved regions and its expression in normal individuals is about 3% that of the beta globin gene. Previous studies have shown that the introduction of the beta-globin CACCC or CAAT can activate the delta-globin gene promoter, but the effect of the distal CACCC element has not yet been tested. In the present study, using site-specific mutagenesis, we have introduced the consensus sequence for the distal and proximal CACCC motif and the CAAT box alone or in combination in the wild-type delta-globin gene promoter. The resulting mutants, as well as the wild type (wt) delta- and beta-globin gene promoters, have been analyzed in a transient expression assay in Cos7, K562, and MEL cell lines. The results show that the CACCC boxes can increase the transcription efficiency of the delta-globin gene promoter in both erythroid and non-erythroid cell systems. The contribution of the two CACCC elements is almost equal in the non-erythroid (Cos7) and erythroid embryonic-fetal cell lines (K562), while the proximal CACCC element is more active in adult erythroid cells (MEL). Nonetheless, duplication of this element does not appear to affect the efficiency of the promoter synergistically. Furthermore, to assess the competitive ability of the delta globin promoter containing the proximal or distal CACCC consensus sequences over the wt beta globin gene promoter, we have carried out transient expression experiments using DNA constructs in which the delta and beta globin gene promoters are linked in cis and are sharing a single enhancer (competitive transient expression). The results show that both CACCC elements are able to activate the delta globin gene promoter in Cos7 and K562 cells, although to a different extent, whereas only the proximal CACCC element is effective in increasing the transcription efficiency in MEL cells. These findings are in agreement with the more severe clinical phenotype produced by the beta-thalassemia mutations affecting the proximal CACCC box as compared with those within the distal CACCC box. The Erythroid Kruppel Like Factor (EKLF) is a nuclear protein restricted to erythroid cells which specifically bind the CACCC box sequence and activate the beta-globin gene. In the present study we carried out transactivation experiments of the mutagenized delta-globin gene promoter by introducing an EKLF expressing construct in erythroid cells. Constructs containing the proximal but not those bearing the distal CACCC element are transactivated. Our results indicate that the proximal CACCC box and, to a lesser extent, also the distal box have a role in the regulated stage specific expression of a beta-like globin gene, and show that the insertion of a single CACCC motif in the delta-globin gene promoter is sufficient to increase its activity. Nevertheless only the delta globin gene promoter containing the proximal CACCC element is able to compete with the wt beta globin gene promoter in the adult erythroid environment. These findings have potential relevance for the future prospective treatment of inherited hemoglobinopathies based on the conversion of the low functioning delta-globin gene into a high functioning beta-like globin gene.