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1.
Eur Rev Med Pharmacol Sci ; 26(24): 9353-9364, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36591844

RESUMO

OBJECTIVE: People commonly use new technologies to promote a healthy lifestyle and help them lose weight through nutritional programs. This study evaluated the quality of individualized meal plans offered by dietary apps. MATERIALS AND METHODS: Ten apps that offer personalized meal plans were selected for the study, weekly meal plans were generated, and the nutritional values of the diets were calculated. The Healthy Diet Indicator and the Diet Quality Index were estimated. RESULTS: Significant differences between apps were observed in the calculated energy values (p<0.0001) and macronutrients (p<0.05), the content of vitamins (vitamin A, E, K, B1, B3, B6, folates, C: p<0.05) and minerals (potassium, calcium, phosphor, magnesium, iron, zinc, copper, manganese: p<0.05), as well as diet quality (p<0.05) and food group consumption (vegetables, fruits, grains, dairy products, vegan products, meat, nuts, fats, sweets, beverages: p<0.05). Most diets covered the demand for the required nutrients, but the percentage of energy from fats, proteins and carbohydrates differed from the recommendations. Moreover, the nutritional values of the diets provided in the apps significantly differ from the values calculated using the nutritional databases. CONCLUSIONS: The meal plans from apps significantly differ in nutrients and food group intake. The quality of the diets offered in the app should be improved.


Assuntos
Dieta , Ingestão de Energia , Humanos , Vitaminas , Minerais , Valor Nutritivo
2.
J Mol Biol ; 432(7): 2405-2427, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32142789

RESUMO

Tight junctions regulate paracellular permeability size and charge selectively. Models have been proposed for the molecular architecture of tight junction strands and paracellular channels. However, they are not fully consistent with experimental and structural data. Here, we analysed the architecture of claudin-based tight junction strands and channels by cellular reconstitution of strands, structure-guided mutagenesis, in silico protein docking and oligomer modelling. Prototypic channel- (Cldn10b) and barrier-forming (Cldn3) claudins were analysed. Förster resonance energy transfer (FRET) assays indicated multistep claudin polymerisation, starting with cis-oligomerization specific to the claudin subtype, followed by trans-interaction-triggered cis-polymerisation. Alternative protomer interfaces were modelled in silico and tested by cysteine-mediated crosslinking, confocal- and freeze fracture EM-based analysis of strand formation. The analysed claudin mutants included also mutations causing the HELIX syndrome. The results indicated that protomers in Cldn10b and Cldn3 strands form similar antiparallel double rows, as has been suggested for Cldn15. Mutually stabilising -hydrophilic and hydrophobic - cis- and trans-interfaces were identified that contained novel key residues of extracellular segments ECS1 and ECS2. Hydrophobic clustering of the flexible ECS1 ß1ß2 loops together with ECS2-ECS2 trans-interaction is suggested to be the driving force for conjunction of tetrameric building blocks into claudin polymers. Cldn10b and Cldn3 are indicated to share this polymerisation mechanism. However, in the paracellular centre of tetramers, electrostatic repulsion may lead to formation of pores (Cldn10b) and electrostatic attraction to barriers (Cldn3). Combining in vitro data and in silico modelling, this study improves mechanistic understanding of paracellular permeability regulation by elucidating claudin assembly and its pathologic alteration as in HELIX syndrome.


Assuntos
Claudina-3/química , Claudinas/química , Multimerização Proteica , Junções Íntimas/química , Animais , Permeabilidade da Membrana Celular , Claudina-3/genética , Claudina-3/metabolismo , Claudinas/genética , Claudinas/metabolismo , Células HEK293 , Humanos , Canais Iônicos , Camundongos , Mutação , Conformação Proteica , Síndrome , Junções Íntimas/metabolismo
3.
Sci Rep ; 9(1): 6737, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31043639

RESUMO

For years, the issues related to the origin of the Goths and their early migrations in the Iron Age have been a matter of hot debate among archaeologists. Unfortunately, the lack of new independent data has precluded the evaluation of the existing hypothesis. To overcome this problem, we initiated systematic studies of the populations inhabiting the contemporary territory of Poland during the Iron Age. Here, we present an analysis of mitochondrial DNA isolated from 27 individuals (collectively called the Mas-VBIA group) excavated from an Iron Age cemetery (dated to the 2nd-4th century A.D.) attributed to Goths and located near Maslomecz, eastern Poland. We found that Mas-VBIA has similar genetic diversity to present-day Asian populations and higher diversity than that of contemporary Europeans. Our studies revealed close genetic links between the Mas-VBIA and two other Iron Age populations from the Jutland peninsula and from Kowalewko, located in western Poland. We disclosed the genetic connection between the Mas-VBIA and ancient Pontic-Caspian steppe groups. Similar connections were absent in the chronologically earlier Kowalewko and Jutland peninsula populations. The collected results seem to be consistent with the historical narrative that assumed that the Goths originated in southern Scandinavia; then, at least part of the Goth population moved south through the territory of contemporary Poland towards the Black Sea region, where they mixed with local populations and formed the Chernyakhov culture. Finally, a fraction of the Chernyakhov population returned to the southeast region of present-day Poland and established the archaeological formation called the "Maslomecz group".


Assuntos
Estruturas Genéticas , Genética Populacional , Migração Humana , População Branca/genética , Arqueologia , Mapeamento Cromossômico , Análise por Conglomerados , Europa (Continente) , Feminino , Marcadores Genéticos , Variação Genética , Geografia , Haplótipos , Humanos , Masculino
4.
Mol Pharm ; 14(8): 2670-2680, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28692796

RESUMO

The aim of this article was to check the physical stability of the amorphous form of probucol at both standard storage and manufacturing conditions. Our studies clearly show that disordered form of the examined, cholesterol lowering, agent stored at ambient pressure does not reveal any tendency toward recrystallization. The physical stability of neat probucol stored at ambient pressure has been investigated (i) at room temperature by means of X-ray diffraction technique (XRD) as well as (ii) at T = 333 K by means of broadband dielectric spectroscopy (BDS). Due to the fact that compression is an important stage of drugs manufacturing we additionally performed physical stability tests of amorphous probucol at elevated pressure. The recrystallization tendency of the examined pharmaceutical has been tracked online from the initial and further up to a few hours after compression by means of the high pressure BDS technique. These experiments indicate that even very small pressure applied during the sample compression immediately induce its recrystallization. Since, the sensitivity on pressure eliminates probucol from the group of physically stable amorphous APIs, its stabilization is required. Taking into account that there are many scientific reports describing the positive effect of coadministration of probucol with the drug atorvastatin, we used the latter as probucol's crystallization inhibitor.


Assuntos
Atorvastatina/química , Pressão , Probucol/química , Espectroscopia Dielétrica , Simulação de Dinâmica Molecular , Temperatura , Difração de Raios X
5.
Mol Pharm ; 13(3): 1111-22, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26836258

RESUMO

In this article, we highlight the benefits coming from the application of amorphous protic ionic systems as active pharmaceutical ingredients (APIs). Using the case of the sumatriptan (STR) drug, we show that the conversion of nonionic API to partially ionized amorphous protic succinate salt (STR SUCC) brings a substantial improvement in apparent solubility. Since in general the disordered systems reveal a tendency to self-arrangement during storage, the dominant part of this article is dedicated to the physical stability issue of sumatriptan and its ionic counterpart. To recognize the crystallization tendency of the studied systems, the calorimetric measurements were performed. Additionally, the role of ion dynamics in spontaneous nucleation of amorphous sumatriptan succinate is discussed. The differential scanning calorimetry analysis of ionic and nonionic sumatriptan reveals many similarities in thermal properties of these APIs as well as distinct differences in their resistance against crystallization in the supercooled liquid state. To determine the long-term physical stability of STR SUCC at room temperature conditions, the time scale of structural relaxation below their glass transition temperatures is estimated. We show that in contrast to nonionic materials, τα predictions of STR SUCC are much more complex and require aging experiments.


Assuntos
Estabilidade de Medicamentos , Líquidos Iônicos , Ácido Succínico/química , Sumatriptana/química , Varredura Diferencial de Calorimetria , Cristalização , Solubilidade , Temperatura de Transição , Difração de Raios X
6.
Semin Cell Dev Biol ; 42: 3-12, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25957516

RESUMO

The tetra-span transmembrane proteins of the claudin family are critical components of formation and function of tight junctions (TJ). Homo- and heterophilic side-by-side (cis) and intercellular head-to-head (trans) interactions of 27 claudin-subtypes regulate tissue-specifically the paracellular permeability and/or tightness between epithelial or endothelial cells. This review highlights the functional impact that has been identified for particular claudin residues by relating them to structural features and architectural characteristics in the light of structural advances, which have been contributed by homology models, cryo-electron microscopy and crystal structures. The differing contributions to the TJ functionalities by claudins are dissected for the transmembrane region, the first and the second extracellular loop of claudins separately. Their particular impact to oligomerisation and TJ strand- and pore-formation is surveyed. Detailed knowledge about structure-function relationships about claudins helps to reveal the molecular mechanisms of TJ assembly and regulation of paracellular permeability, which is yet not fully understood.


Assuntos
Claudinas/química , Claudinas/fisiologia , Animais , Cristalografia por Raios X , Enterotoxinas/química , Humanos , Modelos Moleculares , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Junções Íntimas
7.
ScientificWorldJournal ; 2013: 258758, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24298208

RESUMO

The impact of ionizing radiation generated by a beam of electrons of 25-400 kGy on the stability of such analogs of anthracycline antibiotics as daunorubicin (DAU), doxorubicin (DOX), and epidoxorubicin (EPI) was studied. Based on EPR results, it was established that unstable free radicals decay exponentially with the half-time of 4 days in DAU and DOX and 7 days in EPI after irradiation. Radiation-induced structural changes were analyzed with the use of spectrophotometric methods (UV-Vis and IR) and electron microscope imaging (SEM). A chromatographic method (HPLC-DAD) was applied to assess changes in the contents of the analogs in the presence of their impurities. The study showed that the structures of the analogs did not demonstrate any significant alterations at the end of the period necessary for the elimination of unstable free radicals. The separation of main substances and related substances (impurities and potential degradation products) allowed determining that no statistically significant changes in the content of particular active substances occurred and that their conversion due to the presence of free radicals resulting from exposure to an irradiation of 25 kGy (prescribed to ensure sterility) was not observed.


Assuntos
Antraciclinas/química , Antibacterianos/química , Radiação Ionizante , Esterilização/métodos , Meia-Vida
8.
Br J Pharmacol ; 169(7): 1561-73, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23617601

RESUMO

BACKGROUND AND PURPOSE: The blood-brain barrier (BBB) restricts drug penetration to the brain preventing effective treatment of patients suffering from brain tumours. Intra-arterial injection of short-chain alkylglycerols (AGs) opens the BBB and increases delivery of molecules to rodent brain parenchyma in vivo. The mechanism underlying AG-mediated modification of BBB permeability is still unknown. Here, we have tested the effects of AGs on barrier properties of cultured brain microvascular endothelial cells. EXPERIMENTAL APPROACH: The effects of two AGs, 1-O-pentylglycerol and 2-O-hexyldiglycerol were examined using an in vitro BBB model consisting of primary cultures of rat brain endothelial cells, co-cultured with rat cerebral glial cells. Integrity of the paracellular, tight junction-based, permeation route was analysed by functional assays, immunostaining for junctional proteins, freeze-fracture electron microscopy, and analysis of claudin-claudin trans-interactions. KEY RESULTS: AG treatment (5 min) reversibly reduced transendothelial electrical resistance and increased BBB permeability for fluorescein accompanied by changes in cell morphology and immunostaining for claudin-5 and ß-catenin. These short-term changes were not accompanied by alterations of inter-endothelial tight junction strand complexity or the trans-interaction of claudin-5. CONCLUSION AND IMPLICATIONS: AG-mediated increase in brain endothelial paracellular permeability was short, reversible and did not affect tight junction strand complexity. Redistribution of junctional proteins and alterations in the cell shape indicate the involvement of the cytoskeleton in the action of AGs. These data confirm the results from in vivo studies in rodents characterizing AGs as adjuvants that transiently open the BBB.


Assuntos
Barreira Hematoencefálica/fisiologia , Encéfalo/metabolismo , Claudina-5/farmacologia , Células Endoteliais/metabolismo , Glicerol/análogos & derivados , Glicerol/farmacologia , Junções Íntimas/efeitos dos fármacos , Animais , Barreira Hematoencefálica/ultraestrutura , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoesqueleto , Células Endoteliais/efeitos dos fármacos , Glicerol/farmacocinética , Células HEK293 , Humanos , Microscopia Eletrônica de Transmissão , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Wistar
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 103: 435-41, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23218399

RESUMO

The application of ultraviolet, FT-IR and Raman spectra was proposed for identification studies of the newest penem analogs (doripenem, biapenem and faropenem). An identification of the newest penem analogs based on their separation from related substances was achieved after the application of first derivative of direct spectra in ultraviolet which permitted elimination of overlapping effects. A combination of experimental and theoretical studies was performed for analyzing the structure and vibrational spectra (FT-IR and Raman spectra) of doripenem, biapenem and faropenem. The calculations were conducted using the density functional theory with the B3LYP hybrid functional and 6-31G(d,p) basis set. The confirmation of the applicability of the DFT methodology for interpretation of vibrational IR and Raman spectra of the newest penem analogs contributed to determination of changes of vibrations in the area of the most labile bonds. By employing the theoretical approach it was possible to eliminate necessity of using reference standards which - considering the instability of penem analogs - require that correction coefficients are factored in.


Assuntos
Carbapenêmicos/análise , Tienamicinas/análise , beta-Lactamas/análise , Doripenem , Modelos Moleculares , Teoria Quântica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
10.
Pharmazie ; 67(11): 912-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23210240

RESUMO

An isocratic RP-HPLC-DAD procedure was developed and validated for kinetic analysis of degradation of faropenem in bulk drug substance and in tablets. It involved the use of a C-18 analytical column (5 microm particle size, 250 mm x 4.6 mm), flow rate 1.3 ml/min and 50 microl injection volume. The mobile phase consisted of acetate buffer (pH 3.5) - acetonitrile (70:30 v/v). The determination was carried out at the wavelength of 323 nm. Kinetic studies of faropenem degradation in aqueous solutions included hydrolysis, oxidation, photolysis and thermal degradation. A derivative spectrophotometry was used as an alternative method to compare the observed rate constants.


Assuntos
beta-Lactamas/análise , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos , Estabilidade de Medicamentos , Ácido Clorídrico , Indicadores e Reagentes , Cinética , Padrões de Referência , Espectrofotometria Ultravioleta , beta-Lactamas/química
11.
Gene Ther ; 19(5): 494-503, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21975465

RESUMO

Bacterial toxins are known to be effective for cancer therapy. Clostridium perfringens enterotoxin (CPE) is produced by the bacterial Clostridium type A strain. The transmembrane proteins claudin-3 and -4, often overexpressed in numerous human epithelial tumors (for example, colon, breast, pancreas, prostate and ovarian), are the targeted receptors for CPE. CPE binding to them triggers formation of membrane pore complexes leading to rapid cell death. In this study, we aimed at selective tumor cell killing by CPE gene transfer. We generated expression vectors bearing the bacterial wild-type CPE cDNA (wtCPE) or translation-optimized CPE (optCPE) cDNA for in vitro and in vivo gene therapy of claudin-3- and -4-overexpressing tumors. The CPE expression analysis at messenger RNA and protein level revealed more efficient expression of optCPE compared with wtCPE. Expression of optCPE showed rapid cytotoxic activity, hightened by CPE release as bystander effect. Cytotoxicity of up to 100% was observed 72 h after gene transfer and is restricted to claudin-3-and -4-expressing tumor lines. MCF-7 and HCT116 cells with high claudin-4 expression showed dramatic sensitivity toward CPE toxicity. The claudin-negative melanoma line SKMel-5, however, was insensitive toward CPE gene transfer. The non-viral intratumoral in vivo gene transfer of optCPE led to reduced tumor growth in MCF-7 and HCT116 tumor-bearing mice compared with the vector-transfected control groups. This novel approach demonstrates that CPE gene transfer can be employed for a targeted suicide gene therapy of claudin-3- and -4-overexpressing tumors, leading to the rapid and efficient tumor cell killing in vitro and in vivo.


Assuntos
Claudinas/metabolismo , Enterotoxinas/genética , Genes Transgênicos Suicidas , Terapia Genética/métodos , Neoplasias/terapia , Animais , Efeito Espectador , Linhagem Celular Tumoral , Claudina-3 , Claudina-4 , Claudinas/genética , Células HCT116 , Humanos , Masculino , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 77(2): 554-7, 2010 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-20634123

RESUMO

A spectrophotometric method was developed for the quantitative determination of doripenem in pharmaceutical dosage form (DORIBAX) in the presence of its degradation products. The first-derivative with or without the substration technique, depending on formed products degradation was applied (lambda=324 nm). The method was linear in the range concentration (0.42-11.30)x10(-2)mg L(-1) (r=0.9981), the limits of detection and quantification were 7.60 and 45.0 microg L(-1), respectively. Recovery of doripenem ranged from 99.85 to 102.97% in pharmaceutical dosage form. This method had a good precision (RDS from 0.35 to 2.93%). The observed rate constants for doripenem degradation were comparable to those obtained in recommended HPLC method.


Assuntos
Carbapenêmicos/química , Carbapenêmicos/metabolismo , Espectrofotometria Ultravioleta/métodos , Calibragem , Doripenem , Limite de Detecção , Estrutura Molecular , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Soluções , Espectrofotometria Ultravioleta/normas , Água/química
13.
Cell Mol Life Sci ; 66(22): 3655-62, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19756380

RESUMO

Occludin is a self-associating transmembrane tight junction protein affected in oxidative stress. However, its function is unknown. The cytosolic C-terminal tail contains a coiled coil-domain forming dimers contributing to the self-association. Studying the hypothesis that the self-association is redox-sensitive, we found that the dimerization of the domain depended on the sulfhydryl concentration of the environment in low-millimolar range. Under physiological conditions, monomers and dimers were detected. Masking the sulfhydryl residues in the domain prevented the dimerization but affected neither its helical structure nor cylindric shape. Incubation of cell extracts containing full-length occludin with sulfhydryl reagents prevented the dimerization; a cysteine/alanine exchange mutant also did not show dimer formation. This demonstrates, for the first time, that disulfide bridge formation of the domain is involved in the occludin dimerization. It is concluded that the redox-dependent dimerization of occludin may play a regulatory role in the tight junction assembly under physiological and pathological conditions.


Assuntos
Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Multimerização Proteica , Animais , Células Cultivadas , Dissulfetos/metabolismo , Ditiotreitol/farmacologia , Relação Dose-Resposta a Droga , Humanos , Camundongos , Ocludina , Oxirredução/efeitos dos fármacos , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , Multimerização Proteica/fisiologia , Dodecilsulfato de Sódio/farmacologia , Relação Estrutura-Atividade , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo
14.
J Pharm Biomed Anal ; 50(4): 576-9, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19195811

RESUMO

The degradation of doxorubicin and daunorubcin in the solid state was studied using an HPLC method with UV detection (LiChrospher RP-18, 5 microm, 250 mm x 4 mm; mobile phase: acetonitrile-solution A 1:1, v/v (solution A: 2.88 g of laurisulfate sodium and 1.6 ml of phosphoric acid(V) in 1000 ml); flow rate - 1.4 ml min(-1); UV detection - 254 nm). The degradation of doxorubicin was a first-order reaction depending on the substrate concentration and daunorubicin degraded according to the kinetic model of autocatalysis. The dependence lnk(i)=f(1/T) was described by the equations lnk(DOX)=40.0+/-15.6-(19804+/-5682) (1/T) and lnk(DAU)=35.9+/-11.3-(16581+/-3972) (1/T) at 76.4% RH. The dependence lnk(i)=f(RH%) was described by the equations lnk(DOX)=(8.80+/-3.60) x10(-2) (RH%)-(21.50+/-2.57) and lnk(DAU)=(6.63+/-1.22)x10(-2) (RH%)-(13.35+/-1.68). The thermodynamic parameters (E(a,) DeltaH(not = a), DeltaS(not = a)) of the degradation of doxorubicin and daunorubicin were calculated. Although the degradation of doxorubicin was slower at increased temperature (353-373 K) and relative air humidity (50.9-90.0%), the differences between the influence of temperature and relative air humidity on the stability doxorubicin and of daunorubicin were not significant.


Assuntos
Antibióticos Antineoplásicos/química , Daunorrubicina/química , Doxorrubicina/química , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Umidade , Cinética , Espectrofotometria Ultravioleta/métodos , Temperatura , Termodinâmica
15.
Cell Mol Life Sci ; 63(4): 505-14, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16456617

RESUMO

Tight junctions seal intercellular clefts via membrane-related strands, hence, maintaining important organ functions. We investigated the self-association of strand-forming transmembrane tight junction proteins. The regulatory tight junction protein occludin was differently tagged and cotransfected in eucaryotic cells. These occludins colocalized within the plasma membrane of the same cell, coprecipitated and exhibited fluorescence resonance energy transfer. Differently tagged strand-forming claudin-5 also colocalized in the plasma membrane of the same cell and showed fluorescence resonance energy transfer. This demonstrates self-association in intact cells both of occludin and claudin-5 in one plasma membrane. In search of dimerizing regions of occludin, dimerization of its cytosolic C-terminal coiledcoil domain was identified. In claudin-5, the second extracellular loop was detected as a dimer. Since the transmembrane junctional adhesion molecule also is known to dimerize, the assumption that homodimerization of transmembrane tight junction proteins may serve as a common structural feature in tight junction assembly is supported.


Assuntos
Proteínas de Membrana/química , Junções Íntimas/química , Animais , Proteínas de Bactérias , Linhagem Celular , Cromatografia em Gel , Claudina-5 , Dimerização , Cães , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes , Proteínas de Fluorescência Verde , Humanos , Substâncias Luminescentes , Proteínas Luminescentes , Proteínas de Membrana/metabolismo , Ocludina , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo
16.
Ann Hum Biol ; 29(3): 314-25, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12031140

RESUMO

BACKGROUND: The investigations of Harris lines (HLs) carried out for almost 80 years now have contributed to the understanding of the essence of individual growth and development processes and have enriched the knowledge of the human organism's ontogenetic reaction to adverse environmental factors. AIM: An attempt was made to find a relationship between the influence of adverse living conditions (expressed with the presence of HLs) and an individual's age at death. MATERIALS AND METHODS: The bone material (233 adult individuals; 120 male and 113 female skeletons) was collected at the medieval burial ground in Cedynia, Poland. Recommended methods were used to determine the individuals' sex and age. RESULTS: A statistical relationship was found between the frequency of HLs and the length of the individuals' adult lives. The results obtained justify the conclusion that the individuals who lived a shorter life were exposed to greater pressure from unfavourable environmental conditions (measured with the absolute number of HLs) in the period of growth and development. CONCLUSIONS: Therefore, one can presume that the individuals who died in the maturus age were more resistant to adverse living conditions or their reaction to those conditions was weaker and hence they lived longer.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Tíbia/anatomia & histologia , Adulto , Antropologia Física , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Tíbia/crescimento & desenvolvimento
17.
Homo ; 52(3): 254-76, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12018121

RESUMO

The purpose of the study is to check the relationship between the occurrence of Harris lines and the morphological differentiation of the long bones of the human skeleton as an indicator of living conditions. The bone material (233 adult individuals, including 120 males and 113 females) was collected at a medieval burial ground in Cedynia, Poland. Recommended methods were applied to estimate the sex and age of the individuals (Ferembach et al 1979; Buikstra & Ubelaker 1994). The results obtained indicate that there is no clear relationship between metric characteristics of the studied long bones and the occurrence of Harris lines. Adverse environmental factors, which triggered the occurrence of Harris lines did not strongly affect the growth of long bones and did not change their morphology. Regardless of the phase of ontogenetic development in which the arrested growth lines (HL) formed, no effect of this fact on the final length of bones was observed. Similarly, no statistically significant differences were found in the proportions of bones between individuals reacting to adverse living conditions with the formation of Harris lines and those, whose bones were free of Harris lines. One may assume that Harris lines are of significance in epidemiological research and when assessing the general health profile of a population, but they are less useful in research on morphological reactions of individuals to living conditions.


Assuntos
Tíbia/anatomia & histologia , Tíbia/crescimento & desenvolvimento , Adulto , Determinação da Idade pelo Esqueleto , Antropometria , Meio Ambiente , Estudos Epidemiológicos , Feminino , Nível de Saúde , Humanos , Masculino , Tíbia/patologia
20.
J Neurochem ; 73(1): 139-46, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10386964

RESUMO

To determine the effect of neurotrophins on the survival and morphological differentiation of CNS neurons, we examined NT2-N cells, which provide a unique culture model for terminally differentiated and polar human neurons. Here we report the development of conditions for the long-term culture of NT2-N cells in low density and in chemically defined medium. We show that NT2-N cells express rRNAs for TrkA, TrkB, and TrkC tyrosine kinase receptors and the low-affinity nerve growth factor receptor (p75NTR). All members of the nerve growth factor-related family of neurotrophic factors promote neuronal survival in long-term cultures with approximately 1 ng/ml for half-maximal survival. At high concentrations (>20 ng/ml), the neurotrophins reversed the survival-promoting effect as judged by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] conversion. In contrast to the uniform effect of all neurotrophins on neuronal survival, brain-derived neurotrophic factor selectively induced an increased dendritic complexity. These results demonstrate that NT2-N cells provide a useful model to analyze the effect of neurotrophins on the survival and morphological differentiation of CNS neurons in vitro. In addition, the data indicate that neuronal survival and the development of morphological complexity are differentially regulated in a multireceptor context.


Assuntos
Sobrevivência Celular , Sistema Nervoso Central/citologia , Fatores de Crescimento Neural/farmacologia , Neurônios/fisiologia , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Contagem de Células , Diferenciação Celular , Linhagem Celular , Meios de Cultura , Dendritos/ultraestrutura , Relação Dose-Resposta a Droga , Expressão Gênica , Humanos , Modelos Biológicos , Fatores de Crescimento Neural/administração & dosagem , Neurônios/química , Neurônios/ultraestrutura , Neurotrofina 3 , RNA Mensageiro/análise , Receptores Proteína Tirosina Quinases/genética , Receptores de Fator de Crescimento Neural/genética
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