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Early to Middle Miocene sea-level oscillations of approximately 40-60 m estimated from far-field records1-3 are interpreted to reflect the loss of virtually all East Antarctic ice during peak warmth2. This contrasts with ice-sheet model experiments suggesting most terrestrial ice in East Antarctica was retained even during the warmest intervals of the Middle Miocene4,5. Data and model outputs can be reconciled if a large West Antarctic Ice Sheet (WAIS) existed and expanded across most of the outer continental shelf during the Early Miocene, accounting for maximum ice-sheet volumes. Here we provide the earliest geological evidence proving large WAIS expansions occurred during the Early Miocene (~17.72-17.40 Ma). Geochemical and petrographic data show glacimarine sediments recovered at International Ocean Discovery Program (IODP) Site U1521 in the central Ross Sea derive from West Antarctica, requiring the presence of a WAIS covering most of the Ross Sea continental shelf. Seismic, lithological and palynological data reveal the intermittent proximity of grounded ice to Site U1521. The erosion rate calculated from this sediment package greatly exceeds the long-term mean, implying rapid erosion of West Antarctica. This interval therefore captures a key step in the genesis of a marine-based WAIS and a tipping point in Antarctic ice-sheet evolution.
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Cubierta de Hielo , Elevación del Nivel del Mar/historia , Agua de Mar/análisis , Regiones Antárticas , Modelos Climáticos , Historia AntiguaRESUMEN
PURPOSE: The recent pandemic of severe acute respiratory syndrome (SARS) due to coronavirus (CoV) 2 (SARS-CoV-2) has raised several concerns in reproductive medicine. The aim of this review is to summarize available evidence providing an official position statement of the Italian Society of Andrology and Sexual Medicine (SIAMS) METHODS: A comprehensive Pubmed, Web of Science, Embase, Medline and Cochrane library search was performed. Due to the limited evidence and the lack of studies, it was not possible to formulate recommendations according to the Oxford 2011 Levels of Evidence criteria. RESULTS: Several molecular characteristics of the SARS-CoV-2 can justify the presence of virus within the testis and possible alterations of spermatogenesis and endocrine function. Orchitis has been reported as a possible complication of SARS-CoV infection, but similar findings have not been reported for SARS-CoV-2. Alternatively, the orchitis could be the result of a vasculitis as COVID-19 has been associated with abnormalities in coagulation and the segmental vascularization of the testis could account for an orchitis-like syndrome. Finally, available data do not support the presence of SARS-CoV-2 in plasma seminal fluid of infected subjects. CONCLUSION: Data derived from other SARS-CoV infections suggest that in patients recovered from COVID-19, especially for those in reproductive age, andrological consultation and evaluation of gonadal function including semen analysis should be suggested. Studies in larger cohorts of currently infected subjects are warranted to confirm (or exclude) the presence of risks for male gametes that are destined either for cryopreservation in liquid nitrogen or for assisted reproduction techniques.
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Andrología/normas , Betacoronavirus , Infecciones por Coronavirus/epidemiología , Criopreservación/normas , Preservación de la Fertilidad/normas , Neumonía Viral/epidemiología , Espermatozoides/fisiología , Andrología/tendencias , COVID-19 , Infecciones por Coronavirus/terapia , Criopreservación/tendencias , Preservación de la Fertilidad/tendencias , Humanos , Italia/epidemiología , Masculino , Pandemias , Neumonía Viral/terapia , SARS-CoV-2 , Análisis de Semen/normas , Análisis de Semen/tendencias , Salud Sexual/normas , Sociedades Médicas/normasRESUMEN
Solid-state emitters are excellent candidates for developing integrated sources of single photons. Yet, phonons degrade the photon indistinguishability both through pure dephasing of the zero-phonon line and through phonon-assisted emission. Here, we study theoretically and experimentally the indistinguishability of photons emitted by a semiconductor quantum dot in a microcavity as a function of temperature. We show that a large coupling to a high quality factor cavity can simultaneously reduce the effect of both phonon-induced sources of decoherence. It first limits the effect of pure dephasing on the zero-phonon line with indistinguishabilities above 97% up to 18 K. Moreover, it efficiently redirects the phonon sidebands into the zero-phonon line and brings the indistinguishability of the full emission spectrum from 87% (24%) without cavity effect to more than 99% (76%) at 0K (20K). We provide guidelines for optimal cavity designs that further minimize the phonon-induced decoherence.
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PURPOSE: In this study we hypothesized that the mRNA vector Staufen mediates RNA relocalization during meiotic maturation, and by virtue of its interactions with endoplasmic reticulum, provides a possible mechanism by which protein synthesis is regulated. METHODS: We assessed the expression of staufen (STAU) and calreticulin (CALR), the latter adopted as a marker of the endoplasmic reticulum, in human oocytes at different stages of maturation: GV, metaphase MI and MII. Oocytes were subjected to polymerase chain reaction in order to investigate the expression of STAU and CALR. The corresponding protein products were identified by immunofluorescence and confocal laser scanning microscopy. RESULTS: STAU and CALR were constantly expressed and selectively localized during oocyte maturation. At the GV stage the both proteins displayed a dispersed distribution localization throughout the cytoplasm. Progressing to the MII stage, STAU tended to compartmentalize towards the cortical area of the oocyte clustering in granules of larger sizes. At the MII stage, CALR assumed a pattern reminiscent and possibly coincident with the position of the meiotic spindle. CONCLUSIONS: The changing pattern of STAU distribution during meiotic maturation of human oocytes implicates a novel mechanism for the regulation of protein synthesis based on mRNA localization. Moreover, the unique disposition of CALR at the MII spindle uncovers a physical interaction with endoplasmic reticulum that may mediate cytoskeletal remodelling during oocyte maturation.
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Calreticulina/metabolismo , Citoplasma/metabolismo , Proteínas del Citoesqueleto/metabolismo , Oocitos/metabolismo , Oogénesis/genética , Proteínas de Unión al ARN/metabolismo , Calreticulina/genética , Criopreservación , Proteínas del Citoesqueleto/genética , Femenino , Humanos , Meiosis/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas de Unión al ARN/genética , Huso Acromático/genética , Huso Acromático/metabolismoRESUMEN
BACKGROUND: The aim of this study was to determine the occurrence of gluten sensitivity (GS) in a group of allergic patients and to assess the efficacy of a gluten-free diet (GFD) on the improvement of the symptomatology in those who were diagnosed with GS. METHODS: 262 unrelated allergic patients with gastrointestinal symptoms of obscure origin were tested for GS condition by biopsy. All patients were also genotyped for the typical celiac DQ2 and DQ8 molecules and investigated for several hematological parameters such as antigliadin and antiendomysial antibodies. Patients displaying mucosal lesions were invited to follow a GFD. RESULTS: Seventy-seven of the 262 allergic patients were positive to mucosal lesions, but negative to the antiAGA, antiEMA and to DQ2 and DQ8 molecules. We found, instead, a prevalence of the DQA1*05 allele, whereas anemia of inflammatory origin represented the predominant complaint in our subjects. The positive patients, who, after the GS diagnosis, followed a GFD, exhibited control of symptoms as well as stabilization of the hematological parameters even if allergic manifestations were not abated. CONCLUSIONS: A nonceliac gluten-sensitive enteropathy (NCGSE) commonly occurs in allergic patients. Based on the high prevalence of NCGSE in allergy, it is recommended that biopsy should be part of the routine investigation of allergic disease to offer the benefits of treatment with a GFD to the patients.
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Enfermedad Celíaca/epidemiología , Glútenes/efectos adversos , Hipersensibilidad/complicaciones , Anemia , Asma/complicaciones , Asma/epidemiología , Biopsia , Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/dietoterapia , Enfermedad Celíaca/patología , Dermatitis por Contacto/complicaciones , Dermatitis por Contacto/epidemiología , Dieta Sin Gluten , Duodeno/patología , Femenino , Enfermedades Gastrointestinales/diagnóstico , Enfermedades Gastrointestinales/dietoterapia , Enfermedades Gastrointestinales/epidemiología , Enfermedades Gastrointestinales/patología , Antígenos HLA-DQ/metabolismo , Prueba de Histocompatibilidad , Humanos , Hipersensibilidad/epidemiología , Inflamación , Mucosa Intestinal/patología , Masculino , Rinitis/complicaciones , Rinitis/epidemiologíaRESUMEN
BACKGROUND: X chromosome rearrangements defined a critical region for premature ovarian failure (POF) that extended for >15 Mb in Xq. It has been shown previously that the region could be divided into two functionally distinct portions and suggested that balanced translocations interrupting its proximal part, critical region 1 (CR1), could be responsible for POF through downregulation of ovary expressed autosomal genes translocated to the X chromosome. RESULTS AND CONCLUSION: This study reports that such position effect can indeed be demonstrated by analysis of breakpoint regions in somatic cells of POF patients and by the finding that CR1 has a highly heterochromatic organisation, very different from that of the euchromatic autosomal regions involved in the rearrangements. The chromatin organisation of the POF CR1 is likely to be responsible for the epigenetic modifications observed in POF patients. The characteristics of CR1 and its downregulation in oocytes may very well explain its role in POF and the frequency of the POF phenotype in chromosomal rearrangements involving Xq. This study also demonstrates a large and evolutionary conserved domain of the long arm of the X chromosome, largely corresponding to CR1, that may have structural or functional roles, in oocyte maturation or in X chromosome inactivation.
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Cromosomas Humanos X , Epigénesis Genética , Heterocromatina/metabolismo , Insuficiencia Ovárica Primaria/genética , Animales , Línea Celular , Inmunoprecipitación de Cromatina , Rotura Cromosómica , Cromosomas de los Mamíferos , Biología Computacional/métodos , Metilación de ADN , Femenino , Regulación de la Expresión Génica , Heterocromatina/genética , Histonas/genética , Histonas/metabolismo , Humanos , Ratones , Oocitos/metabolismo , Translocación Genética , Cromosoma XRESUMEN
The morphological characteristics of frozen-thawed human mature oocytes (n = 12) were studied by light and transmission electron microscopy following cryopreservation using a slow cooling protocol including increasing concentrations of ethylene glycol (0.5-1.5 mol/l) and sucrose 0.2 mol/l in the freezing solution. Fresh human mature oocytes (n = 12) were used as controls. Fresh and frozen-thawed oocytes appeared rounded in section, with a homogeneous cytoplasm, an intact oolemma and a continuous zona pellucida. Disorganization of mitochondria-smooth endoplasmic reticulum aggregates and a decreased complement of microvilli and cortical granules were frequently observable in frozen-thawed oocytes. Increased density of the inner zona pellucida, possibly related to the occurrence of zona 'hardening', was sometimes found associated with a reduced amount of cortical granules. In addition, delamination of the zona pellucida was evident in some frozen-thawed samples. Finally, numerous vacuoles and secondary lysosomes were detected in the ooplasm of most frozen-thawed oocytes. In conclusion, frozen-thawed oocytes treated with ethylene glycol may show a variety of ultrastructural alterations, possibly related, at least in part, to the use of this cryoprotectant. Thus, the ethylene glycol-based protocol of slow cooling herein described does not seem to offer significant advantages in terms of oocyte structural preservation.
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Criopreservación/métodos , Oocitos/ultraestructura , Adulto , Glicol de Etileno , Femenino , Humanos , Microscopía Electrónica , Microscopía Electrónica de TransmisiónRESUMEN
Cockayne syndrome (CS) is a human genetic disorder characterized by UV sensitivity, developmental abnormalities, and premature aging. Two of the genes involved, CSA and CSB, are required for transcription-coupled repair (TCR), a subpathway of nucleotide excision repair that removes certain lesions rapidly and efficiently from the transcribed strand of active genes. CS proteins have also been implicated in the recovery of transcription after certain types of DNA damage such as those lesions induced by UV light. In this study, site-directed mutations have been introduced to the human CSB gene to investigate the functional significance of the conserved ATPase domain and of a highly acidic region of the protein. The CSB mutant alleles were tested for genetic complementation of UV-sensitive phenotypes in the human CS-B homologue of hamster UV61. In addition, the CSB mutant alleles were tested for their ability to complement the sensitivity of UV61 cells to the carcinogen 4-nitroquinoline-1-oxide (4-NQO), which introduces bulky DNA adducts repaired by global genome repair. Point mutation of a highly conserved glutamic acid residue in ATPase motif II abolished the ability of CSB protein to complement the UV-sensitive phenotypes of survival, RNA synthesis recovery, and gene-specific repair. These data indicate that the integrity of the ATPase domain is critical for CSB function in vivo. Likewise, the CSB ATPase point mutant failed to confer cellular resistance to 4-NQO, suggesting that ATP hydrolysis is required for CSB function in a TCR-independent pathway. On the contrary, a large deletion of the acidic region of CSB protein did not impair the genetic function in the processing of either UV- or 4-NQO-induced DNA damage. Thus the acidic region of CSB is likely to be dispensable for DNA repair, whereas the ATPase domain is essential for CSB function in both TCR-dependent and -independent pathways.
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Adenosina Trifosfatasas/genética , ADN Helicasas/genética , Reparación del ADN/genética , 4-Nitroquinolina-1-Óxido/farmacología , Adenosina Trifosfatasas/química , Secuencia de Aminoácidos , Animales , Línea Celular , Supervivencia Celular , Células Clonales/efectos de la radiación , Síndrome de Cockayne/genética , Cricetinae , Daño del ADN , ADN Helicasas/química , Enzimas Reparadoras del ADN , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Proteínas de Unión a Poli-ADP-Ribosa , Dímeros de Pirimidina/genética , ARN Mensajero/metabolismo , Tetrahidrofolato Deshidrogenasa/genética , Transfección , Rayos UltravioletaRESUMEN
OBJECTIVE: To assess whether shift work has a cause-effect nexus with the incidence of metabolic syndrome. DESIGN: Retrospective follow-up study, case-control type. RESEARCH METHODS AND PROCEDURES: A total of 202 female and male nurses, aged 23-60 years, having a 1 year minimal follow-up, and without any metabolic syndrome criterion at the first visit were evaluated. The ATP modified criteria were applied for the diagnosis of metabolic syndrome. Moreover smoking habitus, alcohol consumption, educational level and physical activity were considered as bias factors. The sample was divided in two groups doing or not night shifts. RESULTS: The metabolic syndrome incidence resulted significantly greater in shift workers than in other workers (OR: 4.10, 95% CI 1.34-12.55, p = 0.01). The difference was more evident in subjects aged < 40 years (OR = 6.6, 95% CI 1.05-40.85, p = 0.04) the different metabolic syndrome incidence between two groups was detectable even after the multivariate analyse, which considered all the bias factors evaluated. CONCLUSIONS: This study shows for the first time that the night shift work is associated with a greater risk to develop metabolic syndrome in workers healthy in baseline conditions.
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Síndrome Metabólico/diagnóstico , Salud Laboral , Adulto , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Estudios Longitudinales , Masculino , Síndrome Metabólico/epidemiología , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Tolerancia al Trabajo ProgramadoRESUMEN
BACKGROUND: Reports about medical consequences from sedentary work are contradictory. It might be associated with the metabolic syndrome (MS), a collection of cardiovascular risk factors including hypertension, dyslipidemia, insulin resistance and central obesity. No data are currently available on workers using visual display units (VDIU), a potential high risk group, given the sedentariness inherent in this work. PATIENTS AND METHODS: We evaluated MS prevalence in 1547 VDU users with a mean age of 29.7 years and in a control group of 892 individuals with a mean age of 30.2 years who performed non-sedentary work, selected on the basis of similar demographic data. Physical examination and laboratory tests useful for MS diagnosis were performed. RESULTS: MS prevalence was 3.10% in VDU users vs 2.01% in controls (OR 2.048, 95% CI 1.169 to 3.587, p = 0.012). Significance persisted after controlling for confounding factors (e.g, smoking and leisure activity) in a multivariate analysis (OR 1.555, 95% CI 1.03 to 2.690, p < 0.05). CONCLUSIONS: MS should carefully considered when performing health surveillance programmes in VDU users.
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Síndrome Metabólico/epidemiología , Microcomputadores , Enfermedades Profesionales/epidemiología , Adulto , Femenino , Humanos , Masculino , PrevalenciaAsunto(s)
Infección Hospitalaria , Infecciones por Klebsiella , Meningitis , Humanos , Klebsiella pneumoniae , Infección Hospitalaria/tratamiento farmacológico , Ceftazidima/uso terapéutico , Compuestos de Azabiciclo/uso terapéutico , Combinación de Medicamentos , Antibacterianos/uso terapéutico , beta-Lactamasas/genética , Pruebas de Sensibilidad Microbiana , Infecciones por Klebsiella/tratamiento farmacológico , Proteínas BacterianasRESUMEN
In a quantum network based on atoms and photons, a single atom should control the photon state and, reciprocally, a single photon should allow the coherent manipulation of the atom. Both operations require controlling the atom environment and developing efficient atom-photon interfaces, for instance by coupling the natural or artificial atom to cavities. So far, much attention has been drown on manipulating the light field with atomic transitions, recently at the few-photon limit. Here we report on the reciprocal operation and demonstrate the coherent manipulation of an artificial atom by few photons. We study a quantum dot-cavity system with a record cooperativity of 13. Incident photons interact with the atom with probability 0.95, which radiates back in the cavity mode with probability 0.96. Inversion of the atomic transition is achieved for 3.8 photons on average, showing that our artificial atom performs as if fully isolated from the solid-state environment.
RESUMEN
Cockayne syndrome (CS) is a human autosomal recessive disorder characterized by many neurological and developmental abnormalities. CS cells are defective in the transcription coupled repair (TCR) pathway that removes DNA damage from the transcribed strand of active genes. The individuals suffering from CS do not generally develop cancer but show increased neurodegeneration. Two genetic complementation groups (CS-A and CS-B) have been identified. The lack of cancer formation in CS may be due to selective elimination of cells containing DNA damage by a suicidal pathway. In this study, we have evaluated the role of the CSB gene in UV induced apoptosis in human and hamster cells. The hamster cell line UV61 carries a mutation in the homolog of the human CSB gene. We show that both human CS-B and hamster UV61 cells display increased apoptotic response following UV exposure compared with normal cells. The increased sensitivity of UV61 cells to apoptosis is complemented by the transfection of the wild type human CSB gene. In order to determine which functional domain of the CSB gene participates in the apoptotic pathway, we constructed stable cell lines with different CSB domain disruptions. UV61 cells were stably transfected with the human CSB cDNA containing a point mutation in the highly conserved glutamic acid residue in ATPase motif II. This cell line (UV61/ pc3.1-CSBE646Q) showed the same increased apoptosis as the UV61 cells. In contrast, cells containing a deletion in the acidic domain at the N-terminal end of the CSB protein had no effect on apoptosis. This indicates that the integrity of the ATPase domain of CSB protein is critical for preventing the UV induced apoptotic pathway. In primary human CS-B cells, the induction and stabilization of the p53 protein seems to correlate with their increased apoptotic potential. In contrast, no change in the level of either p53 or activation of mdm2 protein by p53 was observed in hamster UV61 cells after UV exposure. This suggests that the CSB dependent apoptotic pathway can occur independently of the transactivation potential of p53 in hamster cells.
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Adenosina Trifosfatasas/fisiología , Apoptosis/efectos de la radiación , Síndrome de Cockayne/patología , ADN Helicasas/fisiología , Reparación del ADN/genética , Proteínas Nucleares , Proteínas Proto-Oncogénicas c-bcl-2 , Rayos Ultravioleta , Secuencia de Aminoácidos , Animales , Apoptosis/fisiología , Línea Celular , Síndrome de Cockayne/enzimología , Síndrome de Cockayne/genética , Cricetinae , Cricetulus , ADN/biosíntesis , ADN Helicasas/química , Enzimas Reparadoras del ADN , Genes p53 , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación Puntual , Proteínas de Unión a Poli-ADP-Ribosa , Estructura Terciaria de Proteína , Proteínas Proto-Oncogénicas/análisis , Proteínas Proto-Oncogénicas c-mdm2 , Proteínas Proto-Oncogénicas p21(ras)/análisis , ARN/biosíntesis , ARN Polimerasa II/antagonistas & inhibidores , Tolerancia a Radiación/genética , Proteínas Recombinantes de Fusión/fisiología , Eliminación de Secuencia , Activación Transcripcional , Transfección , Proteína p53 Supresora de Tumor/fisiología , Rayos Ultravioleta/efectos adversos , Proteína X Asociada a bcl-2RESUMEN
AIM: In in vitro fertilization-embryo transfer (IVF-ET) higher age and low responses are associated with accelerated luteinization of mature follicles rather than diminished responsiveness. The aim of this study was to determine whether an elevated serum progesterone (P) on the day of human chorionic gonadotropin (hCG) administration during gonadotropin stimulation for IVF-ET is associated with age. METHODS: E2 (17beta estradiol) and P concentrations on the day of hCG administration, number and quality of oocytes and embryos, and clinical pregnancies were retrospectively analyzed in 460 women undergoing IVF-ET. We evaluated patients according to age; the 25-30 age group (n=140), the 31-35 age group (n=100), the 36-40 (n=90), and the 41-45 age group (n=130). RESULTS: In the 25-30 age group (n=140) P was 0.67+/-0.3 ng/mL, in the 31-35 age group (n=100) P was 0.87+/-0.2 ng/mL, in the 36-40 age group (n=90) P was 0.95+/-0.2 ng/mL, in the 41-45 age group (n=130) P was 1+/-0.2 ng/mL. The difference between the 25-30 age group and the 41-45 age group was statistically significant (P<0.05). CONCLUSIONS: Periovulatory levels of serum P vary according to ovarian response to controlled ovarian hyperstimulation. Periovulatory P may reflect inadequate steroidogenesis. In women stimulated with recombinant follicle stimulating hormone for IVF, the serum P on the day of hCG administration increases with age.
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Gonadotropina Coriónica/administración & dosificación , Transferencia de Embrión , Fertilización In Vitro , Progesterona/sangre , Adulto , Factores de Edad , Interpretación Estadística de Datos , Estradiol/sangre , Femenino , Humanos , Luteinización , Persona de Mediana Edad , Oocitos/fisiología , Inducción de la Ovulación , Embarazo , Estudios Retrospectivos , Factores de TiempoRESUMEN
BACKGROUND: The efficacy and safety of laparoscopic colorectal surgery have been demonstrated in several well designed trials in recent years. At the same time the experience in the field of laparoscopy in the elderly has increased. The aim of this study was to evaluate retrospectively the experience of laparoscopic colorectal surgery in patients over 75 years in our unit. DESIGN: Retrospective study. SETTING: Surgical Department, San Lorenzo Hospital, Valdagno (VI). SUBJECTS AND METHODS: All the patients over 75 years, out of a total number of 121 unselected patients, undergoing laparoscopic colectomy or laparoscopic abdomino-perineal resection between June 2002 and May 2005. MAIN OUTCOME MEASURES: Postoperative mortality, operating time, conversion rate, morbidity, time of discharge from hospital. RESULTS: Six patients were converted to open surgery. 87 patients over 75 years underwent laparoscopic colorectal surgery. There was no postoperative death, in three cases a reoperation was done, because of postoperative intestinal obstruction in one case (over 75) and for anastomotic fistula in two (one over 75, after low anterior resection). Mean operative time was was 180 minutes (range 150-300). CONCLUSIONS: Laparoscopic colorectal surgery in elderly patients is a safe group of procedures for benign and malignant lesions of large bowel, resulting in a low rate of complications even if the time of operation is increased compared with open procedures. Postoperative pain and hospital stay, with return to normal life, are decreased compared with open surgery.
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Cirugía Colorrectal/métodos , Laparoscopía , Anciano , Humanos , Estudios RetrospectivosRESUMEN
PURPOSE: This study sought to identify, characterize, and localize subtypes of 5-hydroxytryptamine (HT) receptors in rabbit iris-ciliary body. METHODS: Radioligand binding assays were performed with [3H]5-hydroxytryptamine on membranes prepared from rabbit iris-ciliary bodies and on tissue sections subsequently developed by autoradiography. RESULTS: [3H]5-HT appeared to bind to a single population of receptors in membrane preparations of rabbit iris-ciliary body. The apparent affinity of the ligand (KD) was 2.19 nM, and the density of binding sites was 58.3 fmol/mg protein. Binding of [3H] 5-HT exhibited guanosine-5-triphosphate sensitivity. Competitive inhibition experiments were performed to differentiate between 5-HT receptor subtypes. A relative potency order of 5-CT > 5-HT = 8-OH-DPAT > ipsapirone > RU24969 > sumatriptan > ritanserin > ketanserin was demonstrated. The apparent inhibitory constants for the ligands tested fit with the profile expected of binding to 5-HT1A receptors. Inhibition studies with [3H] 5-HT plus 100 nM 8-OH-DPAT (which inhibits binding to 5-HT1A receptors only) representing total binding, indicated that no further displacement occurred when ligands preferentially selective for 5-HT1B, 5-HT1D alpha,1D beta, or 5-HT2C were tested. Total binding of [3H] 5-HT in tissue sections developed by autoradiography was displaced completely by 100 nM 8-OH-DPAT. Melatonin showed little affinity for the [3H] 5-HT binding sites. CONCLUSIONS: A population of 5-HT1A receptors is present in rabbit ciliary processes. There is no evidence to suggest the presence of 5-HT1D alpha, 5-HT1D beta, 5-HT2B, or 5-HT2C receptors in the iris-ciliary body.
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Cuerpo Ciliar/metabolismo , Iris/metabolismo , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Animales , Autorradiografía , Unión Competitiva/efectos de los fármacos , Membrana Celular/metabolismo , Melatonina/farmacología , Conejos , Ensayo de Unión Radioligante , Antagonistas de la Serotonina/farmacología , Agonistas de Receptores de Serotonina/farmacologíaRESUMEN
A method has been developed to establish lines of transformed lymphocytes able to produce in vitro the same anti-sperm antibodies as those naturally occurring in immuno-infertile individuals. We utilized lymphocytes from a male donor whose serum contained anti-sperm antibodies of the IgG class up to the dilution 1:10,000, as detected by means of immunobead binding. T lymphocytes were separated from B lymphocytes using magnetic beads coated with anti-T antibody. B lymphocytes were then placed at a concentration of 5 x 10(6)/ml in a 96-well plate, stimulated with phytohaemagglutinin (PHA) and transformed with Epstein-Barr virus. After a few days, only transformed cells continued growing and these were collected. The supernatant was tested for production of anti-sperm antibodies and those transformed lymphocytes shown to be synthesising antibodies directed against the sperm head and the tail were cloned. We obtained a clone of cells producing antibodies of the IgG1 class directed against the head of the spermatozoon. This oligoclonal antibody (F6) recognized a 58-kDa band from a lysate of sperm membranes and was able to reduce the penetration of zona-free hamster oocytes by capacitated spermatozoa.
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Autoanticuerpos/biosíntesis , Autoanticuerpos/farmacología , Interacciones Espermatozoide-Óvulo/inmunología , Espermatozoides/inmunología , Animales , Línea Celular Transformada , Células Clonales , Cricetinae , Femenino , Herpesvirus Humano 4 , Humanos , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/farmacología , Activación de Linfocitos , MasculinoRESUMEN
Approximately 1% of congenital anomalies relate to pharmacological exposure and are. in theory, preventable. Prevention consists of controlled administration of drugs known to have teratogenic properties (e.g. retinoids, thalidomide). When possible, prevention could take the form of the use of alternative pharmacological therapies during the pre-conception period for certain specific pathologies, selecting the most appropriate agent for use during pregnancy [e.g. haloperidol or a tricyclic antidepressant instead of lithium; anticonvulsant drug monotherapy in place of multitherapy; propylthiouracil instead of thiamazole (methimazole)], and substitution with the most suitable therapy during pregnancy (e.g. insulin in place of oral antidiabetics; heparin in place of oral anticoagulants; alpha-methyldopa instead of ACE inhibitors). Another strategy is the administration of drugs during pregnancy taking into account the pharmacological effects in relation to the gestation period (e.g. avoidance of chemotherapy during the first trimester, avoidance of nonsteroidal anti-inflammatory drugs in the third trimester, and avoidance of high doses of benzodiazepines in the period imminent to prepartum).
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Anticonvulsivantes/efectos adversos , Antidepresivos/efectos adversos , Anomalías Congénitas/etiología , Retinoides/efectos adversos , Teratógenos , Antiinflamatorios no Esteroideos/efectos adversos , Anomalías Congénitas/prevención & control , Femenino , Humanos , EmbarazoRESUMEN
Some biogenic amines, such as putrescine, cadaverine, spermidine and histamine, have been found to be useful as quality indices for the decomposition of fish, so research on the simultaneous analysis of various biogenic amines in food is of interest and importance. The intake of histamine may cause an allergic intoxication known as "scombroid poisoning" while secondary biogenic amines can potentiate the toxicity of histamine and in addition can react with nitrite to form carcinogenic nitrosamines. A new method for the simultaneous determination of underivatized biogenic amines based on ion-exchange chromatography with conductivity detector has been developed. The proposed method offers a number of advantages over previous pulsed amperometric detection and integrated pulsed amperometric detection methods such as simpler extraction procedure and sharp peaks. Separations were performed on a new low hydrophobic weak cation-exchange analytical column. This technique is simple, rapid and useful for routine checks in repetitive analyses.
Asunto(s)
Poliaminas Biogénicas/análisis , Cromatografía Líquida de Alta Presión/métodos , Cromatografía por Intercambio Iónico/métodos , Electroquímica/métodos , Animales , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Histamine is a degradation product of the bacterial decarboxylation of the amino acid histidine, which is present in large amounts in fish tissues of the Clupeidae and Scombridae families and its presence is an indicator of good manufacturing practices and of the state of preservation of some food. A capillary electrophoresis and high-performance liquid chromatography method with diode arrays detection (HPLC-DAD) were compared and validated: no laborious pre-treatment, no clean up and no derivatization was necessary. In both techniques the correlation coefficient exceeded 0.999 for all the analyses carried out during validation. The limit of detection and the limit of quantitation are 1 and 2 mg/kg, respectively, for high-performance liquid chromatography and 0.5 and 1 mg/kg, respectively, for capillary electrophoresis. Good recoveries were observed for the histamine under investigation at all spiking levels and average recoveries were higher than 92% with the relative standard deviation less than 4% for high-performance liquid chromatography and average recoveries were higher than 85% with the relative standard deviation less than 3% for capillary electrophoresis.