RESUMEN
This study presents the mineralogy and strontium isotope ratio (87Sr/86Sr) of 21 pathological biominerals (bladder and kidney stones) collected from patients admitted between 2018 and 2020 at the Department of Urology of the San Pio Hospital (Benevento, southern Italy). Urinary stones belong to the calcium oxalate, purine or calcium phosphate mineralogy types. Their corresponding 87Sr/86Sr range from 0.707607 for an uricite sample to 0.709970 for a weddellite one, and seem to be partly discriminated based on the mineralogy. The comparison with the isotope characteristics of 38 representative Italian bottled and tap drinking waters show a general overlap in 87Sr/86Sr with the biominerals. However, on a smaller geographic area (Campania Region), we observe small 87Sr/86Sr differences between the biominerals and local waters. This may be explained by external Sr inputs for example from agriculture practices, inhaled aerosols (i.e., particulate matter), animal manure and sewage, non-regional foods. Nevertheless, biominerals of patients that stated to drink and eat local water/wines and foods every day exhibited a narrower 87Sr/86Sr range roughly matching the typical isotope ratios of local geological materials and waters, as well as those of archaeological biominerals from the same area. Finally, we conclude that the strontium isotope signature of urinary stones may reflect that of the environmental matrices surrounding patients, but future investigations are recommended to ultimately establish the potential for pathological biominerals as reliable biomonitoring proxies, taking into the account the contribution of the external sources of Sr.
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Agua Potable , Cálculos Urinarios , Animales , Humanos , Isótopos de Estroncio/análisis , Isótopos , Agricultura , EstroncioRESUMEN
Mutations of myelin protein zero gene (MPZ) are found in 5% of Charcot-Marie-Tooth patients. In 2004, Shy et al. identified two main phenotypes associated with them: an early-onset subtype with mainly demyelinating features and a late-onset subgroup with prominent axonal impairment. We evaluated whether novel MPZ mutations described in literature during the last 14 years could still fit with this classification. We collected and revised reports of 69 novel MPZ mutations. Almost 90% of them could be alternatively classified as responsible for: (a) an early-onset phenotype, with first limitations starting before 3 years (2.5 ± 0.50 years), motor milestones delays, frequently severe course and upper limb MNCVs below 15 m/s; (b) late-onset neuropathy, with mean age of onset of 42.8 ± 1.5 years and mean upper limbs motor nerve conduction velocities (MNCVs) of 47.2 ± 1.4 m/s; (c) a phenotype more similar to typical CMT1A neuropathy, with onset during the 2nd decade, MNCV in the range of 15-30 m/s and slowly progressive course. The present work confirms that P0-related neuropathies may be separated into two main distinct phenotypes, while a third, relatively small, group comprehend patients carrying MPZ mutations and a childhood-onset disease, substantiating the subdivision into three groups proposed by Sanmaneechai et al. (Brain 138:3180-3192, 2015). Interestingly, during the last years, an increasing number of novel MPZ mutations causing a late-onset phenotype has been described, highlighting the clinical relevance of late-onset P0 neuropathies. Since the family history for neuropathy is often uncertain, due to the late disease onset, the number of patients carrying this genotype is probably underestimated.
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Enfermedad de Charcot-Marie-Tooth/genética , Proteína P0 de la Mielina/genética , Edad de Inicio , Humanos , Mutación , FenotipoRESUMEN
We analyze a wide gravity low in the Campania Active Volcanic Area and interpret it by a large and deep source distribution of partially molten, low-density material from about 8 to 30 km depth. Given the complex spatial-temporal distribution of explosive volcanism in the area, we model the gravity data consistently with several volcanological and petrological constraints. We propose two possible models: one accounts for the coexistence, within the lower/intermediate crust, of large amounts of melts and cumulates besides country rocks. It implies a layered distribution of densities and, thus, a variation with depth of percentages of silicate liquids, cumulates and country rocks. The other reflects a fractal density distribution, based on the scaling exponent estimated from the gravity data. According to this model, the gravity low would be related to a distribution of melt pockets within solid rocks. Both density distributions account for the available volcanological and seismic constraints and can be considered as end-members of possible models compatible with gravity data. Such results agree with the general views about the roots of large areas of ignimbritic volcanism worldwide. Given the prolonged history of magmatism in the Campania area since Pliocene times, we interpret the detected low-density body as a developing batholith.
RESUMEN
Important complications of diabetes mellitus in the nervous system are represented by diabetic peripheral neuropathy and diabetic encephalopathy. In this context, an important link is represented by neuroactive steroids (i.e., steroids coming from peripheral glands and affecting nervous functionality as well as directly synthesized in the nervous system). Indeed, diabetes does not only affect the reproductive axis and consequently the levels of sex steroid hormones, but also those of neuroactive steroids. Indeed, as will be here summarized, the levels of these neuromodulators present in the central and peripheral nervous system are affected by the pathology in a sex-dimorphic way. In addition, some of these neuroactive steroids, such as the metabolites of progesterone or testosterone, as well as pharmacological tools able to increase their levels have been demonstrated, in experimental models, to be promising protective agents against diabetic peripheral neuropathy and diabetic encephalopathy.
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Encefalopatías/metabolismo , Complicaciones de la Diabetes/metabolismo , Neuropatías Diabéticas/metabolismo , Hormonas Esteroides Gonadales/metabolismo , Vaina de Mielina/metabolismo , Neuropéptidos/metabolismo , Caracteres Sexuales , Animales , Encefalopatías/etiología , Complicaciones de la Diabetes/complicaciones , Femenino , Humanos , MasculinoRESUMEN
SUMMARY: Shotgun metagenomics by high-throughput sequencing may allow deep and accurate characterization of host-associated total microbiomes, including bacteria, viruses, protists and fungi. However, the analysis of such sequencing data is still extremely challenging in terms of both overall accuracy and computational efficiency, and current methodologies show substantial variability in misclassification rate and resolution at lower taxonomic ranks or are limited to specific life domains (e.g. only bacteria). We present here MetaShot, a workflow for assessing the total microbiome composition from host-associated shotgun sequence data, and show its overall optimal accuracy performance by analyzing both simulated and real datasets. AVAILABILITY AND IMPLEMENTATION: https://github.com/bfosso/MetaShot. CONTACT: graziano.pesole@uniba.it. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Metagenómica/métodos , Microbiota/genética , Programas Informáticos , Algoritmos , Bacterias/clasificación , Bacterias/genética , Hongos/clasificación , Hongos/genética , Humanos , Análisis de Secuencia de ADN/métodos , Virus/clasificación , Virus/genética , Flujo de TrabajoRESUMEN
Mitochondrial fission and fusion are essential processes in the maintenance of the skeletal muscle function. The contribution of these processes to muscle development has not been properly investigated in vivo because of the early lethality of the models generated so far. To define the role of mitochondrial fission in muscle development and repair, we have generated a transgenic mouse line that overexpresses the fission-inducing protein Drp1 specifically in skeletal muscle. These mice displayed a drastic impairment in postnatal muscle growth, with reorganisation of the mitochondrial network and reduction of mtDNA quantity, without the deficiency of mitochondrial bioenergetics. Importantly we found that Drp1 overexpression activates the stress-induced PKR/eIF2α/Fgf21 pathway thus leading to an attenuated protein synthesis and downregulation of the growth hormone pathway. These results reveal for the first time how mitochondrial network dynamics influence muscle growth and shed light on aspects of muscle physiology relevant in human muscle pathologies.
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Dinaminas/metabolismo , Músculo Esquelético/metabolismo , Animales , Western Blotting , ADN Mitocondrial/metabolismo , Dinaminas/genética , Inmunoprecipitación , Potencial de la Membrana Mitocondrial/genética , Potencial de la Membrana Mitocondrial/fisiología , Ratones , Ratones Transgénicos , Consumo de Oxígeno/fisiologíaRESUMEN
Dioxins (PCDD/Fs) and polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants. The contamination of food products with dioxins and PCBs is a well studied issue, because food is generally considered the major source of dioxin intake for humans. In Italy, the Regional Monitoring Plan (part of the national residue monitoring plan) used in the field for 2009 has also included the control of environmental pollutants in small egg producers. Following an irregular result, 12 laying hens were transferred into a laboratory controlled environment. Eggs were collected for 60 days and they were weekly analysed for the evaluation of dioxins, dioxin-like PCBs (DL-PCBs), and non-dioxin-like PCBs (NDL-PCBs, six congeners) levels. The dioxins and PCBs contents were determined, according to EPA methods, by gas chromatography ic determination coupled with high resolution mass spectrometry (HRGC-HRMS). The content of PCDD/Fs, DL-PCBs and NDL-PCBs was evaluated weekly by mean from week to week. The concentration of dioxins was lower than DL-PCBs (2.5 pg TEQ g(-1) of fat against 4.5 pg TEQ g(-1) of fat), but we observed the same depletion trend for both pollutants. On the opposite, NDL-PCBs had a different course: we noted there was an increase between weeks 6 and 7, but the mean levels remained very low (about 20 ng g(-1) of fat). The dioxins, and sum of dioxin and DL-PCBs concentration were below the fixed European limits (i.e. 3 pg TEQ g(-1) of fat for dioxins and 6 pg TEQ g(-1) of fat for sum of dioxins and DL-PCBs), beginning from the 3rd week of trial.
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Dioxinas/análisis , Huevos/normas , Contaminantes Ambientales/normas , Contaminación de Alimentos/análisis , Bifenilos Policlorados/normas , Dibenzodioxinas Policloradas/análogos & derivados , Cromatografía de Gases/métodos , Dioxinas/normas , Huevos/análisis , Contaminantes Ambientales/análisis , Italia , Espectrometría de Masas/métodos , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análisis , Dibenzodioxinas Policloradas/normasRESUMEN
MOTIVATION: Alternative splicing has recently emerged as a key mechanism responsible for the expansion of transcriptome and proteome complexity in human and other organisms. Although several online resources devoted to alternative splicing analysis are available they may suffer from limitations related both to the computational methodologies adopted and to the extent of the annotations they provide that prevent the full exploitation of the available data. Furthermore, current resources provide limited query and download facilities. RESULTS: ASPicDB is a database designed to provide access to reliable annotations of the alternative splicing pattern of human genes and to the functional annotation of predicted splicing isoforms. Splice-site detection and full-length transcript modeling have been carried out by a genome-wide application of the ASPic algorithm, based on the multiple alignments of gene-related transcripts (typically a Unigene cluster) to the genomic sequence, a strategy that greatly improves prediction accuracy compared to methods based on independent and progressive alignments. Enhanced query and download facilities for annotations and sequences allow users to select and extract specific sets of data related to genes, transcripts and introns fulfilling a combination of user-defined criteria. Several tabular and graphical views of the results are presented, providing a comprehensive assessment of the functional implication of alternative splicing in the gene set under investigation. ASPicDB, which is regularly updated on a monthly basis, also includes information on tissue-specific splicing patterns of normal and cancer cells, based on available EST sequences and their library source annotation. AVAILABILITY: www.caspur.it/ASPicDB
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Mapeo Cromosómico/métodos , Sistemas de Administración de Bases de Datos , Bases de Datos Genéticas , Sitios de Empalme de ARN/genética , Alineación de Secuencia/métodos , Análisis de Secuencia de ADN/métodos , Interfaz Usuario-Computador , Secuencia de Bases , Gráficos por Computador , Almacenamiento y Recuperación de la Información/métodos , Datos de Secuencia MolecularRESUMEN
The aim of this study was to assess the in vivo efficacy of monoPEGylated GRF(1-29)NH(2) having one PEG(5000) chains attached to either lysine 12 or 21 as compared to the GRF(1-29)NH(2) in rats and pigs. This analogue termed GRF-1PEG(5000) was tested after a single intravenous administration in rats and after a single intravenous or subcutaneous injection in pigs. After 1 h administration, GH concentrations returned to values close to controls in the group of rats injected with GRF(1-29)NH(2). In animals injected with the same dose of GRF-1PEG(5000), the AUC values corresponding to the whole period 0.5-48 h and particularly to the 0.5-8 h period were higher than in the placebo or in the GRF(1-29)NH(2) groups. Interestingly, two additional peaks were observed at about 6 and 8 h following administration. An increase in the response of the endogenous GH peaks was also observed in pigs administered GRF-1PEG(5000) by intravenous route. When GRF-1PEG(5000) was administered subcutaneously to pigs, a significant increase, as compared to placebo and GRF(1-29)NH(2,) in both GH and IGF-I levels was observed. This new analogue might find therapeutic application in paediatric growth hormone deficiency or in aging.
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Hormona Liberadora de Hormona del Crecimiento/análogos & derivados , Polietilenglicoles/química , Sermorelina/análogos & derivados , Sermorelina/farmacología , Animales , Hormona del Crecimiento/sangre , Hormona del Crecimiento/metabolismo , Hormona Liberadora de Hormona del Crecimiento/sangre , Hormona Liberadora de Hormona del Crecimiento/metabolismo , Humanos , Inyecciones Intravenosas , Inyecciones Subcutáneas , Factor I del Crecimiento Similar a la Insulina/análisis , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Sermorelina/administración & dosificación , PorcinosRESUMEN
Synthetically produced GRF1-29 (Sermorelin) has an amino acid composition identical to the N-terminal 29 amino acids sequence of the natural hypothalamic GHRH1-44 (Figure 1). It maintains bioactivity in vitro and is almost equally effective in eliciting secretion of endogenous growth hormone in vivo. The main drawbacks associated with the pharmaceutical use of hGRF1-29 relate to its short half-life in plasma, about 10-20 min in humans, which is caused mostly by renal ultrafiltration and enzymatic degradation at the N terminus. PEGylation has been considered as one valid approach to obtain more stable forms of the peptide, with a longer in vivo half-life and ultimately with increased pharmacodynamic response along the somatotropic axis (endogenous GH, IGF-1 levels). Different PEGylated GRF conjugates were obtained and their bioactivity was tested in vitro and in vivo by monitoring endogenous growth hormone (GH) serum levels after intravenous (i.v.) injection in rats, and intravenous and subcutaneous (s.c.) injection in pigs. It was found that GRF-PEG conjugates are able to bind and activate the human GRF receptor, although with different potency. The effect of PEG molecular weight, number of PEG chains bound and position of PEGylation site on GRF activity were investigated. Mono-PEGylated isomers with a PEG5000 polymer chain linked to Lys 12 or Lys 21 residues, showed high biological activity in vitro, which is similar to that of hGRF1-29, and a higher pharmacodynamic response as compared to unmodified GRF molecule.
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Polietilenglicoles/farmacología , Sermorelina , Animales , Área Bajo la Curva , Disponibilidad Biológica , Semivida , Humanos , Sermorelina/análogos & derivados , Sermorelina/metabolismo , Sermorelina/farmacocinética , Sermorelina/farmacología , Relación Estructura-ActividadRESUMEN
Lipid microparticles (LMs) as a sustained release system for a gonadotropin release hormone (GnRH) antagonist (Antide) were prepared and evaluated. Antide loaded microparticles (Antide-LMs) were obtained by a cryogenic micronization process starting from two different monoglycerides (glyceryl monobehenate and glyceryl monostearate) and using two different incorporation methods (co-melting and solvent evaporation). Antide-LMs, 2% (w/w) loading, were characterized for drug incorporation by RP-HPLC, particle size by laser diffractometry and surface morphology by scanning electron microscopy. In vitro peptide release and in vitro biological activity were also studied. Serum Antide and testosterone levels, as pharmacodynamic marker, were assessed following subcutaneous administration in rats. Antide-LMs showed a mean diameter of approximately 30 micro m and variable Antide release depending on lipid matrix and incorporation method. In vivo experiments demonstrated that detectable Antide plasma levels were present, in the case of Antide-LMs based on Compritol E ATO obtained by co-melting procedure, for at least 30 days after dosing. Testosterone levels were consistent with prolonged pharmacokinetic profiles. In vitro release of Antide from LMs correlated well with the in vivo release. In conclusion, LMs can sustain the release of Antide for at least 1 month. The levels of the initial 'burst' and the extent of the pharmacodynamic effect can be influenced by the lipid characteristics and by process conditions.
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Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Antagonistas de Hormonas/farmacocinética , Microesferas , Oligopéptidos/farmacocinética , Animales , Preparaciones de Acción Retardada/farmacocinética , Femenino , Masculino , Tamaño de la Partícula , Ratas , Ratas Sprague-DawleyAsunto(s)
Tejido Adiposo/patología , Enfermedades de la Médula Ósea/diagnóstico , Hueso Petroso/patología , Tejido Adiposo/cirugía , Adolescente , Adulto , Enfermedades de la Médula Ósea/complicaciones , Mareo/etiología , Exudados y Transudados , Femenino , Cefalea/etiología , Humanos , Imagen por Resonancia Magnética , Hueso Petroso/cirugíaAsunto(s)
Encondromatosis/diagnóstico , Glioma/patología , Hueso Petroso/diagnóstico por imagen , Neoplasias Supratentoriales/patología , Adulto , Diagnóstico Diferencial , Encondromatosis/complicaciones , Encondromatosis/diagnóstico por imagen , Encondromatosis/genética , Glioma/complicaciones , Humanos , Imagen por Resonancia Magnética , Masculino , Paresia/etiología , Hueso Petroso/patología , Silla Turca/patología , Neoplasias Supratentoriales/complicaciones , Tomografía Computarizada por Rayos XAsunto(s)
Aspergilosis/diagnóstico , Meningitis Fúngica/diagnóstico , Meningitis Fúngica/microbiología , Sinusitis/diagnóstico , Sinusitis/microbiología , Adolescente , Aspergilosis/patología , Senos Etmoidales/microbiología , Senos Etmoidales/patología , Femenino , Humanos , Seno Maxilar/microbiología , Seno Maxilar/patología , Meningitis Fúngica/patología , Órbita/microbiología , Órbita/patología , Enfermedades Orbitales/diagnóstico , Enfermedades Orbitales/microbiología , Sinusitis/patologíaRESUMEN
The aim of this study was to assess whether r-hTBP-1 (recombinant human tumor necrosis factor binding protein-1), the soluble form of tumor necrosis factor-alpha (TNF) receptor type 1 might be effective in counteracting the proliferation of ectopic endometrium using an in vivo experimental model of endometriosis. The in vivo model involved transplanting a square fragment of autologus uterine tissue onto the inner surface of the abdominal wall in rats. r-hTBP-1 was administered for 1 week at 10 mg/kg, s.c. divided into two daily injections. The gonadotropin-releasing hormone antagonist antide was used for reference and given at the dose of 2 mg/kg, s.c. every 3 days for 1 week. The animals were killed 2 and 9 days after the last treatment and the size of endometriotic implants measured. Blood samples and spleens were also taken for assessment of estradiol-17beta levels and natural killer (NK) activity in vitro against murine YAC cells, respectively. The results of this study indicate that r-hTBP-1 is effective in reducing the size of the endometriotic-like foci mainly at the later sacrifice time-point when they were significantly decreased by 64% as compared to control animals. As expected, antide induces an almost complete and statistically significant remission both at the 2-day (94%) and the 9-day (88%); sacrifice time-point. Histological examination indicates that, compared to controls, r-hTBP-1 induces a slightly increased degeneration of the stromal tissues of the implants at both examination times and, limitedly to the earlier observation time, of the mucosal epithelium. No differences in the spleen cell NK activity were observed at either sacrifice time-points in any treatment group. Estradiol-17beta concentrations are significantly decreased in the antide-treated groups only at 9 days while no statistically significant changes are found in the animals receiving r-hTBP-1. The results of this study carried out in a rat experimental model of endometriosis provide evidence of the potential effectiveness of r-hTBP-1 in this pathological condition and support the role of TNF in its development.
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Antígenos CD/uso terapéutico , Endometriosis/tratamiento farmacológico , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Factor de Necrosis Tumoral alfa/inmunología , Animales , Antígenos CD/inmunología , Células CHO , Cricetinae , Modelos Animales de Enfermedad , Endometriosis/sangre , Endometriosis/inmunología , Endometriosis/patología , Endometrio/inmunología , Endometrio/patología , Estradiol/sangre , Femenino , Antagonistas de Hormonas/farmacología , Humanos , Células Asesinas Naturales/inmunología , Oligopéptidos/farmacología , Ratas , Ratas Sprague-Dawley , Receptores del Factor de Necrosis Tumoral/inmunología , Receptores Tipo I de Factores de Necrosis Tumoral , Proteínas Recombinantes/uso terapéuticoRESUMEN
We show that normal peripheral nerve myelination depends on strict dosage of the most abundantly expressed myelin gene, myelin protein zero (Mpz). Transgenic mice containing extra copies of Mpz manifested a dose-dependent, dysmyelinating neuropathy, ranging from transient perinatal hypomyelination to arrested myelination and impaired sorting of axons by Schwann cells. Myelination was restored by breeding the transgene into the Mpz-null background, demonstrating that dysmyelination does not result from a structural alteration or Schwann cell-extrinsic effect of the transgenic P(0) glycoprotein. Mpz mRNA overexpression ranged from 30-700%, whereas an increased level of P(0) protein was detected only in nerves of low copy-number animals. Breeding experiments placed the threshold for dysmyelination between 30 and 80% Mpz overexpression. These data reveal new points in nerve development at which Schwann cells are susceptible to increased gene dosage, and suggest a novel basis for hereditary neuropathy.
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Enfermedades Desmielinizantes/congénito , Dosificación de Gen , Proteína P0 de la Mielina/biosíntesis , Proteína P0 de la Mielina/genética , Enfermedades del Sistema Nervioso Periférico/congénito , Animales , Western Blotting , Enfermedades Desmielinizantes/genética , Enfermedades Desmielinizantes/metabolismo , Enfermedades Desmielinizantes/patología , Regulación de la Expresión Génica , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Proteína Básica de Mielina/biosíntesis , Proteína Básica de Mielina/genética , Proteínas de la Mielina/biosíntesis , Proteínas de la Mielina/genética , Especificidad de Órganos , Enfermedades del Sistema Nervioso Periférico/genética , Enfermedades del Sistema Nervioso Periférico/metabolismo , Enfermedades del Sistema Nervioso Periférico/patología , Isoformas de Proteínas/biosíntesis , Isoformas de Proteínas/genética , ARN Mensajero/biosíntesis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células de Schwann/metabolismo , Células de Schwann/ultraestructura , Nervio Ciático/metabolismo , Nervio Ciático/ultraestructuraRESUMEN
Normal peripheral nerve myelination depends on Schwann cell-basal lamina interactions. An important component of Schwann cell basal lamina is laminin--predominantly laminins 2 and 4. Mutations in the alpha 2 chain common to these two isoforms are associated with dysmyelination in mouse (dy) and man (congenital muscular dystrophy). Thus, laminin 2 and 4 receptors are also likely to be important for myelin formation. Several laminin 2/4 receptors are detected at the basal lamina surface of myelin-forming Schwann cells, namely, alpha 6 beta 4 and alpha 6 beta 1 integrins and dystroglycan. The evidence linking these receptors to myelination is suggestive, but not conclusive. Genetic studies have not yet confirmed a role for these molecules in myelin formation. Natural or targeted inactivation of alpha 6, beta 4, and beta 1 integrins and of dystroglycan have profound effects on other tissues causing embryonic or perinatal death before myelination. Therefore, to conditionally inactivate these receptors specifically in myelin-forming Schwann cells, we have constructed and initially characterized a P0-Cre transgene that activates Cre-mediated recombination of loxP-containing genes in peripheral nerve.
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Integrasas/metabolismo , Proteína P0 de la Mielina/fisiología , Receptores de Laminina/fisiología , Células de Schwann/fisiología , Proteínas Virales , Animales , Regulación de la Expresión Génica , Humanos , Integrasas/genética , Laminina/fisiología , Ratones , Ratones Noqueados , Ratones Transgénicos , Proteína P0 de la Mielina/genética , Especificidad de Órganos , Receptores de Laminina/deficiencia , Receptores de Laminina/genética , Proteínas Recombinantes/metabolismo , Nervio Ciático/fisiología , Nervio Ciático/ultraestructura , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismoRESUMEN
It has been established that follicle stimulating hormone (FSH) circulates in the bloodstream as a heterogeneous population of molecules. Individual FSH isoforms, while displaying identical amino acid sequences, differ in their extent of post-translational modification. As a result of these variations, the FSH isoforms exhibit differences in overall charge, degree of sialic acid or sulphate incorporation, receptor binding affinity and plasma half-life. Taking advantage of the fact that these forms can be separated from each other on the basis of their charge, we have evaluated in rats the metabolic clearance rates of the acidic [with an isoelectric point (pI) =ISOdia= 4.8] and the less acidic (pI > 4.8) isoforms of recombinant human FSH (rhFSH) obtained after chromatofocusing. The less acidic isoform group was found to have a faster clearance from the circulation in rats as compared with the acidic isoform group. This finding is in agreement with the lower bioactivity in vivo (as determined by the Steelman-Pohley assay) of the less acidic isoform group, compared with the acidic one. The mass spectra of the two groups of isoforms showed a difference in the sialic acid content thus highlighting the importance of these residues on the in-vivo activity of FSH. Conversely, when the two groups of isoforms were tested in vitro by using the Y1 human FSH receptor (Y1 hFSHR) assay and a reporter gene assay, no significant differences in the biological activities between these preparations were detected when test concentrations were based on mass.