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1.
Opt Express ; 30(5): 7612-7624, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35299519

RESUMO

We report a design methodology for creating high-performance photonic crystals with arbitrary geometric shapes. This design approach enables the inclusion of subwavelength shapes into the photonic crystal unit cell, synergistically combining metamaterials concepts with on-chip guided-wave photonics. Accordingly, we use the term "photonic metacrystal" to describe this class of photonic structures. Photonic metacrystals exploiting three different design freedoms are demonstrated experimentally. With these additional degrees of freedom in the design space, photonic metacrystals enable added control of light-matter interactions and hold the promise of significantly increasing temporal confinement in all-dielectric metamaterials.

2.
BMC Vet Res ; 16(1): 33, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005239

RESUMO

BACKGROUND: In dairy herds, mastitis causes detrimental economic losses. Genetic selection offers a sustainable tool to select animals with reduced susceptibility towards postpartum diseases. Studying underlying mechanisms is important to assess the physiological processes that cause differences between selected haplotypes. Therefore, the objective of this study was to establish an in vivo infection model to study the impact of selecting for alternative paternal haplotypes in a particular genomic region on cattle chromosome 18 for mastitis susceptibility under defined conditions in uniparous dairy cows. RESULTS: At the start of pathogen challenge, no significant differences between the favorable (Q) and unfavorable (q) haplotypes were detected. Intramammary infection (IMI) with Staphylococcus aureus 1027 (S. aureus, n = 24, 96 h) or Escherichia coli 1303 (E. coli, n = 12, 24 h) was successfully induced in all uniparous cows. This finding was confirmed by clinical signs of mastitis and repeated recovery of the respective pathogen from milk samples of challenged quarters in each animal. After S. aureus challenge, Q-uniparous cows showed lower somatic cell counts 24 h and 36 h after challenge (P < 0.05), lower bacterial shedding in milk 12 h after challenge (P < 0.01) and a minor decrease in total milk yield 12 h and 24 h after challenge (P < 0.01) compared to q-uniparous cows. CONCLUSION: An in vivo infection model to study the impact of genetic selection for mastitis susceptibility under defined conditions in uniparous dairy cows was successfully established and revealed significant differences between the two genetically selected haplotype groups. This result might explain their differences in susceptibility towards IMI. These clinical findings form the basis for further in-depth molecular analysis to clarify the underlying genetic mechanisms for mastitis resistance.


Assuntos
Mastite Bovina/genética , Mastite Bovina/microbiologia , Herança Paterna , Animais , Bovinos , Indústria de Laticínios , Escherichia coli , Infecções por Escherichia coli/veterinária , Feminino , Haplótipos , Masculino , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus
3.
J Dairy Sci ; 103(7): 6364-6373, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32307160

RESUMO

Infection and inflammation of the mammary gland, and especially prevention of mastitis, are still major challenges for the dairy industry. Different approaches have been tried to reduce the incidence of mastitis. Genetic selection of cows with lower susceptibility to mastitis promises sustainable success in this regard. Bos taurus autosome (BTA) 18, particularly the region between 43 and 59 Mb, harbors quantitative trait loci (QTL) for somatic cell score, a surrogate trait for mastitis susceptibility. Scrutinizing the molecular bases hereof, we challenged udders from half-sib heifers having inherited either favorable paternal haplotypes for somatic cell score (Q) or unfavorable haplotypes (q) with the Staphylococcus aureus pathogen. RNA sequencing was used for an in-depth analysis of challenge-related alterations in the hepatic transcriptome. Liver exerts highly relevant immune functions aside from being the key metabolic organ. Hence, a holistic approach focusing on the liver enabled us to identify challenge-related and genotype-dependent differentially expressed genes and underlying regulatory networks. In response to the S. aureus challenge, we found that heifers with Q haplotypes displayed more activated immune genes and pathways after S. aureus challenge compared with their q half-sibs. Furthermore, we found a significant enrichment of differentially expressed loci in the genomic target region on BTA18, suggesting the existence of a regionally acting regulatory element with effects on a variety of genes in this region.


Assuntos
Predisposição Genética para Doença , Fígado/metabolismo , Mastite Bovina/imunologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus , Transcriptoma , Animais , Bovinos , Indústria de Laticínios , Suscetibilidade a Doenças/veterinária , Feminino , Haplótipos , Glândulas Mamárias Animais/metabolismo , Mastite Bovina/genética , Fenótipo , Locos de Características Quantitativas , Seleção Genética , Análise de Sequência de RNA , Infecções Estafilocócicas/genética , Staphylococcus aureus/genética , Vacinação/veterinária
4.
BMC Vet Res ; 15(1): 241, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296208

RESUMO

BACKGROUND: A major challenge in modern medicine and animal husbandry is the issue of antimicrobial resistance. One approach to solving this potential medical hazard is the selection of farm animals with less susceptibility to infectious diseases. Recent advances in functional genome analysis and quantitative genetics have opened the horizon to apply genetic marker information for efficiently identifying animals with preferential predisposition regarding health traits. The current study characterizes functional traits with a focus on udder health in dairy heifers. The animals were selected for having inherited alternative paternal haplotypes for a genomic region on Bos taurus chromosome (BTA) 18 genetically associated with divergent susceptibility to longevity and animal health, particularly mastitis. RESULTS: In the first weeks of lactation, the q heifers which had inherited the unfavorable (q) paternal haplotype displayed a significantly higher number of udder quarters with very low somatic cell count (< 10,000 cells / ml) compared to their paternal half-sib sisters with the favorable (Q) paternal haplotype. This might result in impaired mammary gland sentinel function towards invading pathogens. Furthermore, across the course of the first lactation, there was indication that q half-sib heifers showed higher somatic cell counts, a surrogate trait for udder health, in whole milkings compared to their paternal half-sib sisters with the favorable (Q) paternal haplotype. Moreover, heifers with the haplotype Q had a higher feed intake and higher milk yield compared to those with the q haplotype. Results of this study indicate that differences in milk production and calculated energy balance per se are not the main drivers of the genetically determined differences between the BTA18 Q and q groups of heifers. CONCLUSIONS: The paternally inherited haplotype from a targeted BTA18 genomic region affect somatic cell count in udder quarters during the early postpartum period and might also contribute to further aspects of animal's health and performance traits due to indirect effects on feed intake and metabolism.


Assuntos
Glândulas Mamárias Animais/fisiologia , Herança Paterna , Animais , Bovinos , Mapeamento Cromossômico , Ingestão de Alimentos/genética , Metabolismo Energético/genética , Feminino , Haplótipos/genética , Lactação/genética , Masculino , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/genética , Período Pós-Parto
5.
BMC Vet Res ; 15(1): 285, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395056

RESUMO

The original article [1] contained an error whereby the captions to Figs 2 and 3 were mistakenly inverted; this has now been corrected.

6.
J Dairy Sci ; 102(11): 9983-9994, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31521359

RESUMO

The susceptibility of animals to periparturient diseases has a great effect on the economic efficiency of dairy industries, on the frequency of antibiotic treatment, and on animal welfare. The use of selection for breeding cows with reduced susceptibility to diseases offers a sustainable tool to improve dairy cattle farming. Several studies have focused on the association of distinct bovine chromosome 18 genotypes or haplotypes with performance traits. The aim of this study was to test whether selection of Holstein Friesian heifers via SNP genotyping for alternative paternal chromosome 18 haplotypes associated with favorable (Q) or unfavorable (q) somatic cell scores influences postpartum reproductive and metabolic diseases. Thirty-six heifers (18 Q and 18 q) were monitored from 3 wk before calving until necropsy on d 39 (± 4 d) after calving. Health status and rectal temperature were measured daily, and body condition score and body weight were assessed once per week. Blood samples were drawn twice weekly, and levels of insulin, nonesterified fatty acids, insulin-like growth factor-I, growth hormone, and ß-hydroxybutyrate were measured. Comparisons between the groups were performed using Fisher's exact test, chi-squared test, and the GLIMMIX procedure in SAS. Results showed that Q-heifers had reduced incidence of metritis compared with q-heifers and were less likely to develop fever. Serum concentrations of ß-hydroxybutyrate were lower and insulin-like growth factor-I plasma concentrations were higher in Q- compared with q-heifers. However, the body condition score and withers height were comparable between haplotypes, but weight loss tended to be lower in Q-heifers compared with q-heifers. No differences between the groups were detected concerning retained fetal membranes, uterine involution, or onset of cyclicity. In conclusion, selection of chromosome 18 haplotypes associated with a reduced somatic cell score resulted in a decreased incidence of postpartum reproductive and metabolic diseases in this study. The presented data add to the existing knowledge aimed at avoiding negative consequences of genetic selection strategies in dairy cattle farming. The underlying causal mechanisms modulated by haplotypes in the targeted genomic region and immune competence necessitate further investigation.


Assuntos
Bovinos/genética , Cromossomos de Mamíferos , Haplótipos , Período Pós-Parto , Reprodução , Seleção Genética , Ácido 3-Hidroxibutírico/sangue , Animais , Peso Corporal , Bovinos/metabolismo , Doenças dos Bovinos/genética , Indústria de Laticínios , Ácidos Graxos não Esterificados/sangue , Feminino , Hormônio do Crescimento/sangue , Insulina/sangue , Lactação , Placenta Retida/veterinária , Polimorfismo de Nucleotídeo Único , Gravidez
7.
Clin Anat ; 31(4): 560-565, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29322603

RESUMO

The zygomaticus major (ZM) is important for the human smile. There are conflicting data about whether the zygomatic or buccal branches of the facial nerve are responsible for its motor innervation. The literature provides no precise distinction of the transition zone between these two branch systems. In this study, a definition to distinguish the facial nerve branches at the level of the body of the zygoma is proposed. In the light of this definition, we conducted an anatomical study to determine how the source of innervation of the ZM was distributed. A total of 96 fresh-frozen cadaveric facial halves were dissected under loupe magnification. A hemiparotidectomy was followed by antegrade microsurgical dissection. Any branch topographically lying superficial to the zygoma or touching it was classed as zygomatic, and any neighboring inferior branch was considered buccal. The arborization of the facial nerve was diffuse in all cases. In 64 out of 96 specimens (67%, 95% CI: 56% to 76%), zygomatic branches innervated the ZM. Buccal branches innervated ZM in the other 32 facial halves (33%, 95% CI: 24% to 44%). There were no differences in respect of sex or facial side. All facial halves displayed additional branches, which crossed the muscle on its inner surface without supplying it. In 31 specimens, a nerve branch ran superficial to ZM in its cranial third. According to our classification, the zygomaticus major is innervated by zygomatic branches in 67% of cases and by buccal branches in 33%. Clin. Anat. 31:560-565, 2018. © 2018 Wiley Periodicals, Inc.


Assuntos
Músculos Faciais/inervação , Nervo Facial/anatomia & histologia , Variação Anatômica , Feminino , Humanos , Masculino , Sorriso/fisiologia
8.
Urologe A ; 60(11): 1424-1431, 2021 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-34652475

RESUMO

Early radical cystectomy (RC) is a therapeutic option for non-muscle invasive bladder cancer (NMIBC). The 15-year overall survival after early RC in NMIBC patients is about 70%. Nevertheless, RC is associated with significant morbidity and mortality and therefore requires careful patient selection. The aim of the following review is to assess the selection process for early RC in NMIBC. Especially, the new European Association of Urology (EAU) risk calculator identifying NMIBC patients with very high risk for disease progression is described in detail. Furthermore, the technical aspects of the procedure are evaluated. A review of the current literature (PubMed) and national and international guideline recommendations was also conducted.


Assuntos
Cistectomia , Neoplasias da Bexiga Urinária , Humanos , Invasividade Neoplásica , Seleção de Pacientes , Neoplasias da Bexiga Urinária/cirurgia
9.
Microbiol Mol Biol Rev ; 70(3): 755-88, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16959968

RESUMO

The gram-positive bacterium Staphylococcus aureus is a frequent component of the human microbial flora that can turn into a dangerous pathogen. As such, this organism is capable of infecting almost every tissue and organ system in the human body. It does so by actively exporting a variety of virulence factors to the cell surface and extracellular milieu. Upon reaching their respective destinations, these virulence factors have pivotal roles in the colonization and subversion of the human host. It is therefore of major importance to obtain a clear understanding of the protein transport pathways that are active in S. aureus. The present review aims to provide a state-of-the-art roadmap of staphylococcal secretomes, which include both protein transport pathways and the extracytoplasmic proteins of these organisms. Specifically, an overview is presented of the exported virulence factors, pathways for protein transport, signals for cellular protein retention or secretion, and the exoproteomes of different S. aureus isolates. The focus is on S. aureus, but comparisons with Staphylococcus epidermidis and other gram-positive bacteria, such as Bacillus subtilis, are included where appropriate. Importantly, the results of genomic and proteomic studies on S. aureus secretomes are integrated through a comparative "secretomics" approach, resulting in the first definition of the core and variant secretomes of this bacterium. While the core secretome seems to be largely employed for general housekeeping functions which are necessary to thrive in particular niches provided by the human host, the variant secretome seems to contain the "gadgets" that S. aureus needs to conquer these well-protected niches.


Assuntos
Proteínas de Bactérias/metabolismo , Staphylococcus/metabolismo , Proteínas de Bactérias/fisiologia , Microscopia Eletrônica , Transporte Proteico/fisiologia , Proteômica/métodos , Transdução de Sinais/fisiologia , Staphylococcus/patogenicidade , Staphylococcus/ultraestrutura , Staphylococcus aureus/metabolismo , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/ultraestrutura , Virulência
10.
Sci Rep ; 10(1): 6865, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32300183

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

11.
Sci Rep ; 10(1): 1935, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029860

RESUMO

We developed a time-efficient semi-automated axon quantification method using freeware in human cranial nerve sections stained with paraphenylenediamine (PPD). It was used to analyze a total of 1238 facial and masseteric nerve biopsies. The technique was validated by comparing manual and semi-automated quantification of 129 (10.4%) randomly selected biopsies. The software-based method demonstrated a sensitivity of 94% and a specificity of 87%. Semi-automatic axon counting was significantly faster (p < 0.001) than manual counting. It took 1 hour and 47 minutes for all 129 biopsies (averaging 50 sec per biopsy, 0.04 seconds per axon). The counting process is automatic and does not need to be supervised. Manual counting took 21 hours and 6 minutes in total (average 9 minutes and 49 seconds per biopsy, 0.52 seconds per axon). Our method showed a linear correlation to the manual counts (R = 0.944 Spearman rho). Attempts have been made by several research groups to automate axonal load quantification. These methods often require specific hard- and software and are therefore only accessible to a few specialized laboratories. Our semi-automated axon quantification is precise, reliable and time-sparing using publicly available software and should be useful for an effective axon quantification in various human peripheral nerves.

12.
Clin Hemorheol Microcirc ; 70(1): 1-13, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30010114

RESUMO

BACKGROUND AND OBJECTIVES: Early persistent facial paralysis is characterized by intact muscles of facial expression through maintained perfusion but lacking nerve supply. In facial reanimation procedures aiming at restoration of facial tone and dynamics, neurotization through a donor nerve is performed. Critical for reanimating target muscles is axonal capacity of both donor and recipient nerves. In cases of complete paralysis, the proximal stump of the extratemporal facial nerve trunk may be selected as a recipient site for coaptation. To further clarify the histological basis of this facial reanimation procedure we conducted a human cadaver study examining macro and micro anatomical features of the facial nerve trunk including its axonal capacity in human cadavers. Axonal loads, morphology and morbidity of different donor nerves are discussed reviewing literature in context of nerve transfers. METHODS: From 6/2015 to 9/2016 in a group of 53 fresh frozen cadavers a total of 106 facial halves were dissected. Biopsies of the extratemporal facial nerve trunk (FN) were obtained at 1 cm distal to the stylomastoid foramen. After histological processing and digitalization of 99 specimens available, 97 were selected eligible for fascicle counts and 87 fulfilled quality criteria for a semi-automated computer-based axon quantification software using ImageJ/Fiji. RESULTS: An average of 3.82 fascicles (range, 1 to 9) were noted (n = 97). 6684±1884 axons (range, 2655- 12457) were counted for the entire group (n = 87). Right facial halves showed 6364±1904 axons (n = 43). Left facial halves demonstrated 6996±1833 axons (n = 44) with no significant difference (p = 0.73). Female cadavers featured 6247±2230 (n = 22), male showed 6769±1809 axons (n = 40). No statistical difference was seen between genders (p = 0.59). A comparison with different studies in literature is made. The nerve diameter in 82 of our specimens could be measured at 1933±424 µm (range, 975 to 3012). CONCLUSIONS: No donor nerve has been described to match axonal load or fascicle number of the extratemporal facial nerve main trunk. However, the masseteric nerve may be coapted for neurotization of facial muscles with a low complication rate and good clinical outcomes. Nerve transfer is indicated from 6 months after onset of facial paralysis if no recovery of facial nerve function is seen.


Assuntos
Músculos Faciais/anatomia & histologia , Nervo Facial/anatomia & histologia , Paralisia Facial/cirurgia , Transferência de Nervo/métodos , Axônios , Músculos Faciais/patologia , Nervo Facial/patologia , Paralisia Facial/patologia , Feminino , Humanos , Masculino
13.
Clin Biochem ; 49(3): 260-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26500002

RESUMO

OBJECTIVES: Anti-Müllenria hormone (AMH) is an established biomarker for assessing ovarian reserve and predicting response to controlled ovarian stimulation. Its routine clinical use is hampered by the variability and low-throughput of available enzyme-linked immunosorbent assays (ELISA). The presented study examined if a fully automated AMH electrochemiluminescence assay (ECLIA; Elecsys® AMH assay, Roche Diagnostics) was suitable for measuring AMH levels in healthy women and in those diagnosed with polycystic ovary syndrome (PCOS). DESIGN AND METHODS: Five European laboratories evaluated the Elecsys® AMH assay independently under routine conditions over eight months. Within-run imprecision, repeatability, intermediate precision, linearity and functional sensitivity were assessed. The Elecsys® AMH assay was compared to a manual ELISA microtiter plate format test (AMH Gen II ELISA, modified version; Beckman Coulter Inc.) using 1729 routine serum samples. AMH reference intervals were determined in 887 healthy women with regular menstrual cycle aged 20­50 years, and 149 women diagnosed with PCOS. RESULTS: The fully automated Elecsys® AMH assay showed excellent precision, linearity, and functional sensitivity. The coefficient of variation was 1.8% for repeatability and 4.4% for intermediate precision. Values measured with the Elecsys® AMH assay were highly correlated with the manual ELISA method (modified version) but 24­28% lower. Reference intervals showed the expected AMH decline with age in healthy women and increased AMH levels in women with PCOS. CONCLUSIONS: The Elecsys® AMH assay demonstrated good precision under routine conditions, and is suitable for determining AMH levels in serum and lithium-heparin plasma.


Assuntos
Hormônio Antimülleriano/análise , Ensaio de Imunoadsorção Enzimática/métodos , Medições Luminescentes/métodos , Adolescente , Adulto , Hormônio Antimülleriano/sangue , Automação Laboratorial/instrumentação , Automação Laboratorial/métodos , Biomarcadores/sangue , Ensaio de Imunoadsorção Enzimática/normas , Feminino , Humanos , Laboratórios , Medições Luminescentes/normas , Ciclo Menstrual/metabolismo , Pessoa de Meia-Idade , Síndrome do Ovário Policístico/sangue , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Biochim Biophys Acta ; 1267(1): 6-14, 1995 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-7779869

RESUMO

Proteoglycans are mediators of cellular adhesion and regulate growth factor activities. Proteoglycans of B lymphocytes undergo structural changes during B cell ontogeny which may correspond to the specific requirements of the respective microenvironment of the maturing cell. We analyzed three human B cell lines representing pre-B cells (Nalm-6), activated B cells (Jok-1) and plasma cells (U266) for their cellular proteoglycans. Gel filtration of the 35S-labeled macromolecules of the three cell lines revealed an increase in size in the order Nalm-6 < Jok-1 < U266. In Jok-1 and U266 cells the major pool of proteoglycans consisted of proteochondroitin sulfates of 50 to 90 kDa. These proteolglycans carried a protein core of approx. 30 kDa to which 1 to 3 glycosaminoglycan chains in the range of 28 to 32 kDa were attached. In Nalm-6 cells only free chondroitin sulfate chains of 23 kDa, but no intact proteoglycans, were detected. Chondroitin sulfate chains were predominantly composed of chondroitin-4-sulfate, those of Nalm-6 and U266 cells additionally contained 10-20% of unsulfated disaccharides. In U266 cells 30% of glycosaminoglycans consisted of heparan sulfate either bound to pure proteoheparan sulfate or to chondroitin sulfate/heparan sulfate hybrid-proteoglycans. Earlier, syndecan-1 was described as a hybrid proteoglycan containing heparan sulfate/chondroitin sulfate chains which is transcribed by murine B cells at early and late maturation stages. In order to see whether syndecan is transcribed by the human B cell lines used here, we measured expression of syndecan mRNA by the reverse transcriptase polymerase chain reaction. Similar to murine lymphocytes, syndecan-specific mRNA was detected in Nalm-6 and U266 cells, equivalent to early and late B cells, but not in lymphoblastoid Jok-1 cells. However, Nalm-6 cells do not produce proteoheparan sulfate. In these cells, syndecan synthesis may be blocked at the translational level. Also, the proteoglycans of U266 are different from syndecan-1 in their composition of glycosaminoglycans and in size of protein cores. Together, these results indicate that the major pool of proteoglycans produced by human B cells consists of proteochondroitin sulfate and additionally in later stages of a smaller proportion of proteoheparan sulfate which is not identical to syndecan-1. During distinct phases of B cell differentiation, modulations in the glycosaminoglycan moiety concerning size and sulfation of glycosaminoglycan chains were also found.


Assuntos
Linfócitos B/metabolismo , Proteoglicanas/metabolismo , Linfócitos B/citologia , Diferenciação Celular , Linhagem Celular , Proteoglicanas de Sulfatos de Condroitina/química , Condroitinases e Condroitina Liases , Glicosaminoglicanos/química , Glicosilação , Humanos , Glicoproteínas de Membrana/genética , Proteoglicanas/química , Proteoglicanas/genética , Proteoglicanas/isolamento & purificação , RNA Mensageiro/análise , Sindecana-1 , Sindecanas
15.
Leukemia ; 10(6): 1000-11, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8667635

RESUMO

Cell surface-expressed proteoglycans mediate contacts to extracellular matrix (ECM). Human B lymphocytes produce a species of a proteochondroitin sulfate (CSPG) with an approximate molecular mass of 135-150 kDa. Using a monoclonal antibody (mAb) against B cell CSPG in flow cytometry we found that this CSPG is expressed on tumor cells of patients with CD19+ common acute lymphoblastic leukemia and on the corresponding cell lines Nalm-6, Reh and KM3. The CSPG is also present on hairy cell leukemia JOK-1 cells and weakly on the myeloma line U266. Concomitant with CSPG expression, Nalm-6 cells express the integrins alpha 5/beta 1 (CD49e/CD29) and alpha 6/beta 1 (CD49f/CD29), adhesion receptors for fibronectin and laminin, in contrast to the other two cell lines tested. Expression patterns of these adhesion receptors and CSPG were paralleled by strong adhesion of Nalm-6 to fibronectin and laminin. Adhesion of Nalm-6 to fibronectin was inhibited by the alpha 5-specific antibody SAM 1 by 80% whereas the alpha 6-specific antibody GoH3 reduced binding to laminin only by 20%. A possible involvement of surface-expressed CSPG in adhesion to ECM components was investigated by 24 h incubation of Nalm-6 cells with p-nitrophenyl-beta-D-xyloside, an inhibitor of proteoglycan glycosylation. By this treatment, both adhesion of Nalm-6 to laminin and expression of CSPG were reduced by 40-50%. Furthermore, addition of chondroitin-6-sulfate, a structural element of Nalm-6 CSPG, reduced adhesion of Nalm-6 to laminin by 60%. Chondroitin-4-sulfate, heparin and heparan sulfate did not effectively inhibit the adhesion process. These observations suggest that surface-expressed CSPG may be involved in binding of Nalm-6 cells to laminin and that the specific sulfation pattern of chondroitin-6-sulfate may be essential in this regard.


Assuntos
Proteoglicanas de Sulfatos de Condroitina/metabolismo , Laminina/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Antígenos CD/metabolismo , Adesão Celular , Membrana Celular/imunologia , Membrana Celular/metabolismo , Fibronectinas/metabolismo , Humanos , Integrina alfa5 , Integrina alfa6 , Integrina alfa6beta1 , Integrina beta1/metabolismo , Integrinas/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Receptores de Fibronectina/metabolismo , Receptores de Laminina/metabolismo , Células Tumorais Cultivadas/imunologia , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/patologia
17.
FEMS Microbiol Lett ; 145(1): 63-9, 1996 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-8931328

RESUMO

Two catalases of B. subtilis have been studied which are subject to two different regulatory mechanisms. Whereas KatA belongs to the group of proteins specifically induced by oxidative stress, KatE is a general delta B-dependent stress protein, not induced by oxidative stress. There are two mechanisms of oxidative stress resistance, the adaptive resistance induced by low H2O2 concentrations and an unspecific resistance acquired in glucose-starved cells. Mutants lacking KatA are defective in the adaptive resistance and both exponentially growing and glucose-starved cells are 100-fold more sensitive against lethal concentrations of H2O2. Under both conditions, however, a katE mutant was just as resistant as the wild type. Therefore, the role of KatE in oxidative stress tolerance remains obscure. sigB mutants which are no longer able to induce delta B-dependent general stress proteins in glucose-starved cells are characterized by a strong impairment in the unspecific oxidative stress resistance but not in the H2O2-induced oxidative stress resistance. This is the first evidence that sigB mutants have an obvious phenotype compared to the wild type and indicates that delta B-dependent general stress proteins may function in providing starving cells with resistance against oxidative stress.


Assuntos
Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Catalase/genética , Estresse Oxidativo/fisiologia , Fator sigma/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/metabolismo , Catalase/metabolismo , Eletroforese em Gel Bidimensional , Etanol/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/fisiologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/fisiologia , Glucose/farmacologia , Temperatura Alta , Peróxido de Hidrogênio/farmacologia , Mutação/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Fator sigma/metabolismo , Solventes/farmacologia
18.
Health Aff (Millwood) ; 17(6): 181-93, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9916368

RESUMO

This DataWatch assesses Medicare beneficiaries' understanding of the differences between their managed care and fee-for-service Medicare options. A telephone survey was used to evaluate knowledge levels among 1,673 beneficiaries residing in five Medicare markets with high managed care penetration. Half of the sample were enrolled in health maintenance organizations (HMOs) and half in the traditional Medicare program. The findings show that 30 percent of beneficiaries know almost nothing about HMOs; only 11 percent have adequate knowledge to make an informed choice; and HMO enrollees have significantly lower knowledge levels of the differences between the two delivery systems. These findings have implications for educating beneficiaries about their expanded choices.


Assuntos
Participação da Comunidade/estatística & dados numéricos , Planos de Pagamento por Serviço Prestado/estatística & dados numéricos , Sistemas Pré-Pagos de Saúde/estatística & dados numéricos , Medicare , Idoso , Tomada de Decisões , Escolaridade , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Estados Unidos
19.
Med Care Res Rev ; 57(4): 464-90, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11105513

RESUMO

To make an informed selection between traditional Medicare and a Medicare managed care plan, a consumer needs to understand the implications of choosing one over the other. What are the implications of plan design for care, cost, and patient autonomy? Consumers need information about these questions. However, a barrier to developing this consumer information is the lack of a consistent body of evidence. An intermediate step is to tap expert knowledge. The purpose of this study is to use expert consensus (across a spectrum of health care experts) to identify the implications of plan design. Experts were surveyed and the degree to which there is consensus provides an initial picture of what experts judge to be important to the consumer. The findings show that experts agree on several implications associated with choosing managed care over the traditional Medicare plan. They also agree that many of these attributes vary considerably across health plans.


Assuntos
Participação da Comunidade , Tomada de Decisões , Medicare/organização & administração , Idoso , Coleta de Dados , Técnica Delphi , Pesquisa sobre Serviços de Saúde , Humanos , Modelos Organizacionais , Estados Unidos
20.
Carbohydr Res ; 302(1-2): 85-95, 1997 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-9249954

RESUMO

Proteoglycans interact with soluble proteins such as growth factors and thereby regulate extracellular signals. During B lymphocyte maturation, secretion of proteoglycans may be functionally related to the different requirements of the respective maturation stage. In order to address this question we compared structures of proteoglycans released by three B lymphocyte lines which correspond to different maturation stages. Plasma-cell type U266 cells secreted the largest proteoglycans (150 kDa), followed by mature B cells JOK-1 (130 kDa) and pre-B cells Nalm 6 (90 kDa). On average, secreted proteoglycans carried four glycosaminoglycan chains with molecular masses ranging each from 32 kDa (U266) to 23 kDa (Nalm 6). All three cell lines secreted more than 90% of their proteoglycans possessing chondroitin sulfate chains having chondroitin-4-sulfate (delta Di-4S) as the prevalent disaccharide unit. In these proteochondroitin sulfates, unsulfated chondroitin (delta Di-0S) was present in smaller quantities and chondroitin-6-sulfate (delta Di-6S)-containing proteoglycan was released only by Nalm 6 and U266 cells. Cell line Nalm 6 exclusively produced proteochondroitin sulfate, whereas in culture medium of JOK-1 and U266 a small amount of proteoheparan sulfate was found also. In all three cell lines, treatment with chondroitinase ABC released a protein of 30 kDa and chemical deglycosylation resulted in a core protein of 21 kDa. In addition to pure proteochondroitin sulfate, a small portion of proteoheparan sulfate with a protein moiety of 30 kDa was detected after heparitinase treatment in supernatants of JOK-1 and U266. Thus, our results indicate that released proteoglycans may undergo modulations in their glycosaminoglycan moieties during B-cell differentiation. This may have functional consequences at the level of growth factor regulation.


Assuntos
Linfócitos B/metabolismo , Proteoglicanas/metabolismo , Linfócitos B/citologia , Linhagem Celular , Centrifugação com Gradiente de Concentração , Condroitina Liases/metabolismo , Sulfatos de Condroitina/análise , Sulfatos de Condroitina/química , Sulfatos de Condroitina/metabolismo , Cromatografia em Agarose , Cromatografia em Gel , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Glicosilação , Heparitina Sulfato/análise , Humanos , Mesilatos/metabolismo , Peso Molecular , Polissacarídeo-Liases/metabolismo , Proteoglicanas/química , Proteoglicanas/isolamento & purificação
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