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1.
Transfusion ; 63(2): 339-347, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36515262

RESUMEN

BACKGROUND: Viral safety of blood products in Germany has improved significantly over the last two decades. We describe the second documented transfusion-transmitted (TT) episode for the hepatitis C virus (HCV) in Germany since mandatory nucleic acid amplification techniques (NAT) screening was introduced in 1999. STUDY DESIGN AND METHODS: When a repeat donor who had tested negative for anti-HCV tested positive for HCV RNA by NAT in a minipool (MP) of eight, a look-back procedure was initiated. Qualitative, quantitative and genotyping assays were used to investigate the titers of the quarantined fresh frozen plasma (FFP) from the donor and a serum sample from the recipient of the pooled platelet concentrate (PPC). Amplified products of 5'UTR and HVR1 were used for sequence comparison to characterize the HCV genomic identity of donor and recipient samples. RESULTS: All NAT tests utilized in this procedure were able to detect a low HCV RNA titer (~15 IU/ml) in the FFP from the donation. Dilution of FFP by factor 8 was performed to mimic an MP, and the detection rate correlated well with the claimed sensitivity of the tests. Analysis of donor and recipient samples revealed genotype 3a viral transmission confirmed by sequence analysis. CONCLUSION: This TT HCV case could have been prevented by individual donation (ID) NAT. However, a low titer blood donation in the window period (WP) is very rare. Residual risk calculation for TT HCV in the WP revealed that, compared to MP-NAT testing, ID-NAT would improve blood safety only marginally.


Asunto(s)
Hepacivirus , Hepatitis C , Humanos , Hepacivirus/genética , Donantes de Sangre , Hepatitis C/diagnóstico , Alemania , ARN , Técnicas de Amplificación de Ácido Nucleico/métodos , Tamizaje Masivo
2.
Transfus Med Hemother ; 50(1): 26-29, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36818770

RESUMEN

Background and Objectives: In 1993, a quarantine storage of 6 months was introduced for plasma for transfusion and was reduced to 4 months in 2003, owing to the improvements of screening assays used in German blood establishments. The presented survey analyses the value of quarantine storage under the current screening conditions. Materials and Methods: From 2015 to 2019, we collected data on the total amount of released quarantine plasma as well as on the number of quarantine plasma not released due to a reactive screening test of a follow-up donation. Results: Responding establishments covered 84% of plasma units released within the sampled period. In 3,583,913 (99.98%) of the total 3,584,664 test pairs, all screening assays revealed a negative result, leading to plasma release from quarantine storage. In 442 out of the residual 751 cases, confirmed positive results for human immunodeficiency virus (24), hepatitis C virus (22), or hepatitis B virus (396) were obtained in the follow-up donations. Of them, 372 revealed negative ID-NAT results in their retain samples confirmed by using highly sensitive individual donor nucleic acid amplification technology. In 70 cases, no testing of retain samples was performed as plasma was released for fractionation. The maximum theoretical risk for an undetected human immunodeficiency virus, hepatitis C or B virus infection was less than 0.0001%. Conclusion: No positive donation were found under the current screening regime and the quarantine storage during the 5-year survey period. In view of the current type and sensitivity of screening tests in German blood establishments, the results allow a reassessment of the value of quarantine storage of plasma regarding duration and release modalities. Due to the more sensitive donor screening, shorter quarantine periods as well as dispensing quarantine storage can be discussed. A reduction in the safety standard of plasma transfusions need not be feared, and the availability of plasma for transfusions could be facilitated.

3.
Transfus Med Hemother ; 50(2): 129-134, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37066055

RESUMEN

Background and Objectives: A sufficient supply of safe, high-quality blood components for transfusion is essential to the healthcare system in Germany. The requirements for the current reporting system are laid down in the German Transfusion Act. The present work elaborates on the advantages and limitations of the current reporting system and investigates the feasibility of a pilot project that collects specific data on blood supply based on weekly reports. Materials and Methods: Selected data on blood collection and supply from 2009 to 2021 derived from the §21 German Transfusion Act database were examined. In addition, a pilot study over a period of 12 months was conducted on a voluntary basis. The number of red blood cell (RBC) concentrates was documented and stock availability was calculated weekly. Results: From 2009 to 2021, the annual number of RBC concentrates decreased from 4.68 to 3.43 million, the per capita distribution decreased from 58 to 41 RBC concentrates per 1,000 inhabitants. These figures did not change significantly during the COVID-19 pandemic. The data of the 1-year pilot project represented 77% of the released RBC concentrates in Germany. Percentage share of O RhD positive RBC concentrates fluctuated between 35% and 22% and for O RhD negative concentrates between 17% and 5%. The availability of O RhD positive RBC concentrate stocks varied between 2.1 and 7.6 days. Conclusion: The data presented shows a decrease in annual RBC concentrate sales over an 11-year period and no further change over the past 2 years. A weekly monitoring of blood components detects acute problems in RBC provision and supply. Close monitoring seems helpful but should be combined with a nationwide supply strategy.

4.
Clin Oral Investig ; 26(3): 2909-2919, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35018500

RESUMEN

OBJECTIVES: To evaluate interdental biofilm reduction and composition after powered toothbrushing with a side-to-side (sonic) toothbrush compared to manual toothbrushing following single brushing exercises in periodontally healthy young adults. MATERIALS AND METHODS: All participants brushed with a side-to-side toothbrush without toothpaste in four different modes: toothbrush (a) inactivated without instruction (OFF-NI), (b) activated without instruction (ON-NI), (c) inactivated with instruction (OFF-I), and (d) activated with instruction (ON-I) at consecutive visits (single brushing exercises). Before and after brushing, the Approximal Plaque Index (API) was assessed at three interdental spaces and plaque samples were taken from two interdental sites. Biofilm reduction and composition were analyzed microbiologically by total bacterial load and 16S rRNA sequencing. RESULTS: Thirty participants (age: 22.9 ± 2.5 years) completed the study. Most participants showed no or incomplete plaque removal assessed by API following single brushing exercises, while the frequency of API reduction was higher after ON-NI compared to OFF-I (p = 0.023). Irrespective of the brushing mode, a significant reduction of total bacterial load was detected with lower bacterial counts after OFF-NI compared to ON-NI (p = 0.008) and ON-I (p = 0.007). Biofilm composition showed slight changes in the relative abundances of bacterial taxa, regardless of the brushing mode. CONCLUSIONS: Manual and powered toothbrushing with a side-to-side toothbrush, with and without instruction, showed incomplete interdental biofilm removal in periodontally healthy young adults following single brushing exercises. CLINICAL RELEVANCE: Data has to be validated in further studies on other groups, however, in periodontally healthy young adults, additional devices seem to be necessary for sufficient interdental cleaning.


Asunto(s)
Biopelículas , Cepillado Dental , Adulto , Índice de Placa Dental , Diseño de Equipo , Humanos , ARN Ribosómico 16S , Adulto Joven
5.
Artículo en Alemán | MEDLINE | ID: mdl-35024894

RESUMEN

Infections with hepatitis B, C, and E virus (HBV, HCV, and HEV) can be transmitted via blood and cause severe acute or chronic liver infections. To ensure the safety of blood donations and protect recipients from virus transmissions, blood donations in Germany are tested for viral genomes using nucleic acid amplification techniques (NATs) as well as for viral antigens and antibodies by serological testing. This article describes the relevant regulations on the safety of blood and blood products in Germany and the various screening methods. The safety of blood products is assessed.Currently used NAT methods for detection of hepatitis viruses are based either on polymerase chain reaction (PCR) or isothermal methods such as transcription-mediated amplification (TMA), which enable a highly sensitive detection of viral infections and thereby contribute to the reduction of the diagnostic window. Antigen tests for the detection of viral surface protein of hepatitis B virus in blood donations were introduced in the 1970s in order to prevent potential transmissions. Since the introduction of mandatory testing for HCV-specific antibodies in 1992, HCV NAT testing in 1999, anti-HBc antibody testing in 2006, and the non-mandatory HBV NAT, which is voluntarily performed by most of the blood establishments, blood safety has increased tremendously. Only a few isolated cases of transfusion-transmitted infections in the early window period have been reported since. The success of the recent introduction of mandatory HEV NAT testing in 2020 will have to be assessed in the upcoming years. Besides blood donor screening, the system for blood safety in Germany is supplemented by additional measures for donor selection and pathogen inactivation.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Hepatitis B , Donantes de Sangre , Seguridad de la Sangre , ADN Viral , Alemania , Hepatitis B/diagnóstico , Hepatitis B/prevención & control , Humanos , Tamizaje Masivo
6.
Immunol Cell Biol ; 99(1): 107-115, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32762092

RESUMEN

Multiple sclerosis (MS) is a disabling neuroinflammatory disease. Its etiology is unknown, but both oxidative stress and inflammation appear to be involved in disease pathology. Macrophages are the predominant cell type in acute inflammatory brain lesions in MS. Macrophages produce proinflammatory and toxic molecules that promote demyelination and are key players in phagocytosis/degradation of myelin sheathes. Lipoic acid (LA) is an inexpensive, endogenously produced small molecule that exhibits antioxidant and anti-inflammatory effects. Treatment with LA is protective in MS and other inflammatory diseases. To examine the mechanism(s) by which LA may attenuate inflammatory lesion activity in MS, we used healthy control and MS cells to evaluate the effects of LA on levels of inflammatory cytokines, phagocytosis and the immunomodulator cyclic adenosine monophosphate (cAMP) in monocytes and monocyte-derived macrophages (MDMs). LA treatment resulted in a generally less inflammatory phenotype of monocytes and MDMs from healthy controls, and (to a lesser degree) MS donors. LA inhibited monocyte secretion of cytokines relevant to MS in monocytes, including tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-1ß; LA effects on secretion of these cytokines in MDMs were mixed with inhibition of TNF-α and IL-6, but stimulation of IL-1ß, the latter perhaps as a result of altered macrophage polarization. LA inhibited phagocytosis in both monocytes and MDMs, and increased cAMP levels in monocytes. LA may modulate inflammatory cytokine secretion and phagocytosis via a cAMP-mediated mechanism.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Ácido Tióctico , Células Cultivadas , Citocinas , Humanos , Macrófagos , Monocitos , Esclerosis Múltiple/tratamiento farmacológico , Ácido Tióctico/farmacología , Factor de Necrosis Tumoral alfa
7.
Transfus Med Hemother ; 47(4): 314-324, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32884504

RESUMEN

BACKGROUND: Platelet concentrates play an important role in transfusion medicine. Their short lifespan and lack of robustness require efforts to ensure adequate product quality. In this study, we compared the in vitro quality of the main concentrate types, pooled platelet concentrate (PPC) from whole blood donations, and platelet concentrate from single-donor apheresis (APC). METHODS: Twenty PPCs and 20 APCs prepared in plasma were analyzed on days 2, 4, and 7 of storage. Variables related to metabolism, degranulation, platelet aggregation, P-selectin expression, and annexin V binding were analyzed. Morphology was assessed by transmission electron microscopy of ultrathin sections. A microfluidic device was applied to test the effects of shear stress on platelet function. RESULTS: The metabolic parameters indicated stable storage conditions throughout the 7-day period. The resting discoid form was the prevailing morphology on days 2 and 4 in the PPCs and APCs. Chemokine release and receptor shedding of soluble P-selectin and soluble CD40L equally increased in PPCs and APCs. Aggregation responses to ADP and collagen were heterogeneous, with marked losses in collagen responsiveness on day 4 in individual concentrates. Baseline expression of P-selectin in PPCs and APCs was low, and inducibility of P-selectin was well preserved until day 4. Under shear stress, equal adhesiveness and stability were found with platelets from PPCs and APCs. CONCLUSIONS: Platelets from PPCs and APCs showed similar in vitro function and stability parameters. However, platelet concentrates presented a high variability and individual concentrates an impaired functional capability. Identifying the factors contributing to this would help increase product reliability.

8.
Vox Sang ; 114(5): 443-450, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31012114

RESUMEN

BACKGROUND AND OBJECTIVES: In Germany, in addition to standard blood donor screening, further mandatory tests were introduced for HCV-RNA, HIV-1-RNA and for anti-HBc. Screening for HBV-DNA is optional. This study investigates the benefits of these additional tests for the detection of HIV, HCV, and HBV infections among German blood donors. MATERIALS AND METHODS: From 2008 to 2015 we collected data on blood donations exclusively testing NAT positive (NAT yield) or reactive in only one of the screening assays. Assuming a Poisson distribution, we calculated NAT yield/reactive only rates on a per donation basis (number of yield/reactive only cases divided by the number of donations tested in the period under review) with 95% confidence intervals. RESULTS: Responding establishments covered 95% of the donations. We identified 20 HIV-1-NAT, 61 HCV-NAT and 29 HBV-NAT yield cases among approximately 46 million blood donations tested corresponding to 0·43 HIV-1 NAT, 1·32 HCV-NAT, and 0·64 HBV-NAT yield cases per million blood donations tested. For one HBsAg reactive only case and 23 anti-HBc reactive only cases in repeat donors, infection was confirmed by ID-NAT which translates into 0·02 and 0·55 cases per million donations tested. During the 8-year-observation period, one HIV-1, no HCV and four HBV transmissions associated with donations in the viremic pre-seroconversion window period were reported. CONCLUSION: Annually, NAT screening alone detected 2·5 HIV-1, 7·6 HCV, and 3·6 HBV infectious donations; anti-HBc screening alone identified 2·9 infectious donations of repeat donors with occult HBV infection. Overall, the survey results support that the currently practiced donor HIV/HCV/HBV screening strategy in Germany does ensure a high standard of blood safety.


Asunto(s)
Infecciones por VIH/diagnóstico , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B/diagnóstico , Hepatitis C/diagnóstico , Inmunoensayo/métodos , Alemania , VIH-1 , Humanos , Tamizaje Masivo , Pruebas Serológicas , Ácidos Urónicos
9.
J Cell Sci ; 129(15): 2983-96, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27335427

RESUMEN

Preovulatory granulosa cells express the low-molecular-mass MAP2D variant of microtubule-associated protein 2 (MAP2). Activation of the luteinizing hormone choriogonadotropin receptor by human choriogonadotropin (hCG) promotes dephosphorylation of MAP2D on Thr256 and Thr259. We sought to evaluate the association of MAP2D with the cytoskeleton, and the effect of hCG on this association. MAP2D partially colocalized, as assessed by confocal immunofluorescence microscopy, with the vimentin intermediate filament and microtubule cytoskeletons in naive cells. In vitro binding studies showed that MAP2D bound directly to vimentin and ß-tubulin. Phosphorylation of recombinant MAP2D on Thr256 and Thr259, which mimics the phosphorylation status of MAP2D in naive cells, reduces binding of MAP2D to vimentin and tubulin by two- and three-fold, respectively. PKA-dependent phosphorylation of vimentin (Ser32 and Ser38) promoted binding of vimentin to MAP2D and increased contraction of granulosa cells with reorganization of vimentin filaments and MAP2D from the periphery into a thickened layer surrounding the nucleus and into prominent cellular extensions. Chemical disruption of vimentin filament organization increased progesterone production. Taken together, these results suggest that hCG-stimulated dephosphorylation of MAP2D at Thr256 and Thr259, phosphorylation of vimentin at Ser38 and Ser72, and the resulting enhanced binding of MAP2D to vimentin might contribute to the progesterone synthetic response required for ovulation.


Asunto(s)
Células de la Granulosa/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Ovulación , Vimentina/metabolismo , Animales , Gonadotropina Coriónica/farmacología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Células de la Granulosa/efectos de los fármacos , Humanos , Filamentos Intermedios/efectos de los fármacos , Filamentos Intermedios/metabolismo , Microscopía Confocal , Microtúbulos/efectos de los fármacos , Microtúbulos/metabolismo , Persona de Mediana Edad , Proteínas Mutantes/metabolismo , Ovulación/efectos de los fármacos , Fosforilación/efectos de los fármacos , Fosfotreonina/metabolismo , Progesterona/farmacología , Unión Proteica/efectos de los fármacos , Ratas Sprague-Dawley , Proteínas Recombinantes/metabolismo , Solubilidad
10.
Biochem Biophys Res Commun ; 475(1): 19-24, 2016 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-27157139

RESUMEN

Dimethyl fumarate (DMF) was recently approved by the FDA for the treatment of relapsing remitting MS. The pathology of MS is a result of both immune dysregulation and oxidative stress induced damage, and DMF is believed to have therapeutic effects on both of these processes. However, the mechanisms of action of DMF are not fully understood. To determine if DMF is able to activate signaling cascades that affect immune dysregulation, we treated human peripheral blood mononuclear cells with DMF. We discovered that DMF stimulates cyclic adenosine monophosphate (cAMP) production after 1 min treatment in vitro. cAMP is a small molecule second messenger that has been shown to modulate immune response. Using pharmacological inhibitors, we determined that adenylyl cyclase mediates DMF induced cAMP production; DMF activated the prostaglandin EP2 receptor to produce cAMP. This response was not due to increased endogenous production of prostaglandin E2 (PGE2), but was enhanced by addition of exogenous PGE2. Furthermore, we determined that the bioactive metabolite of DMF, monomethyl fumarate (MMF), also stimulates cAMP production. These novel findings suggest that DMF may provide protection against MS by inhibiting immune cell function via the cAMP signaling pathway.


Asunto(s)
AMP Cíclico/inmunología , Dimetilfumarato/farmacología , Inmunosupresores/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Subtipo EP2 de Receptores de Prostaglandina E/inmunología , Transducción de Señal/efectos de los fármacos , Adenilil Ciclasas/inmunología , Dinoprostona/inmunología , Humanos , Leucocitos Mononucleares/inmunología , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/inmunología
11.
Proc Natl Acad Sci U S A ; 109(44): E2979-88, 2012 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-23045700

RESUMEN

Controlled maturation of ovarian follicles is necessary for fertility. Follicles are restrained at an immature stage until stimulated by FSH secreted by pituitary gonadotropes. FSH acts on granulosa cells within the immature follicle to inhibit apoptosis, promote proliferation, stimulate production of steroid and protein hormones, and induce ligand receptors and signaling intermediates. The phosphoinositide 3-kinase (PI3K)/AKT (protein kinase B) pathway is a pivotal signaling corridor necessary for transducing the FSH signal. We report that protein kinase A (PKA) mediates the actions of FSH by signaling through multiple targets to activate PI3K/AKT. PKA uses a route that promotes phosphorylation of insulin receptor substrate-1 (IRS-1) on Tyr(989), a canonical binding site for the 85-kDa regulatory subunit of PI3K that allosterically activates the catalytic subunit. PI3K activation leads to activation of AKT through phosphorylation of AKT on Thr(308) and Ser(473). The adaptor growth factor receptor bound protein 2-associated binding protein 2 (GAB2) is present in a preformed complex with PI3K heterodimer and IRS-1, it is an A-kinase anchoring protein that binds the type I regulatory subunit of PKA, and it is phosphorylated by PKA on Ser(159). Overexpression of GAB2 enhances FSH-stimulated AKT phosphorylation. GAB2, thus, seems to coordinate signals from the FSH-stimulated rise in cAMP that leads to activation of PI3K/AKT. The ability of PKA to commandeer IRS-1 and GAB2, adaptors that normally integrate receptor/nonreceptor tyrosine kinase signaling into PI3K/AKT, reveals a previously unrecognized route for PKA to activate a pathway that promotes proliferation, inhibits apoptosis, enhances translation, and initiates differentiation of granulosa cells.


Asunto(s)
Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Hormona Folículo Estimulante/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfoproteínas/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/fisiología , Proteínas Adaptadoras Transductoras de Señales , Regulación Alostérica , Animales , Dominio Catalítico , Proteínas Quinasas Dependientes de AMP Cíclico/fisiología , Activación Enzimática , Femenino , Fosforilación , Ratas , Ratas Sprague-Dawley
12.
Biophys J ; 105(2): 385-97, 2013 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-23870260

RESUMEN

The proteorhodopsin family consists of retinal proteins of marine bacterial origin with optical properties adjusted to their local environments. For green proteorhodopsin, a highly specific mutation in the EF loop, A178R, has been found to cause a surprisingly large redshift of 20 nm despite its distance from the chromophore. Here, we analyze structural and functional consequences of this EF loop mutation by time-resolved optical spectroscopy and solid-state NMR. We found that the primary photoreaction and the formation of the K-like photo intermediate is almost pH-independent and slower compared to the wild-type, whereas the decay of the K-intermediate is accelerated, suggesting structural changes within the counterion complex upon mutation. The photocycle is significantly elongated mainly due to an enlarged lifetime of late photo intermediates. Multidimensional MAS-NMR reveals mutation-induced chemical shift changes propagating from the EF loop to the chromophore binding pocket, whereas dynamic nuclear polarization-enhanced (13)C-double quantum MAS-NMR has been used to probe directly the retinylidene conformation. Our data show a modified interaction network between chromophore, Schiff base, and counterion complex explaining the altered optical and kinetic properties. In particular, the mutation-induced distorted structure in the EF loop weakens interactions, which help reorienting helix F during the reprotonation step explaining the slower photocycle. These data lead to the conclusion that the EF loop plays an important role in proton uptake from the cytoplasm but our data also reveal a clear interaction pathway between the EF loop and retinal binding pocket, which might be an evolutionary conserved communication pathway in retinal proteins.


Asunto(s)
Proteínas Bacterianas/química , Fototransducción , Rodopsina/química , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Concentración de Iones de Hidrógeno , Cinética , Datos de Secuencia Molecular , Mutación , Estructura Terciaria de Proteína , Retinoides/química , Rodopsina/genética , Rodopsina/metabolismo , Rodopsinas Microbianas
13.
Biol Reprod ; 88(2): 41, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23303679

RESUMEN

The fibrous sheath (FS) is a flagellar cytoskeletal structure unique to sperm that surrounds the outer dense fibers and axoneme. Its primary components are A-kinase anchoring proteins (AKAPs) 3 and 4, which suggests that the FS affects flagellar beating via the scaffolding of signaling pathways necessary for motility. Sperm proteins ROPN1 and ROPN1L bind AKAP3. To determine the role of ROPN1 and ROPN1L in sperm function, we created mice deficient in ROPN1 (RKO), mice deficient in ROPN1L (RLKO), and double knockout mice (DKO). All three strains of mice had normal testicular morphology and spermatogenesis. Only the DKOs had obvious defects in sperm morphology (thinning and shredding of the principal piece), which was accompanied by a reduction in AKAP3 levels. RLKO mice had slightly reduced sperm motility and increased levels of ROPN1. RKO mice had moderately impaired motility and increased levels of ROPN1L. DKO sperm were immotile. We have previously determined that RKO male mice are subfertile, and DKO males are infertile. Together these data indicate that ROPN1L and ROPN1 compensate for each other in the absence of the opposing protein, possibly to maintain AKAP3 incorporation in the FS. Sperm from mice lacking ROPN1L exhibited reductions in both cAMP-dependent protein kinase (PKA) phosphorylation of a 270-kDa protein (perhaps FSCB), and in capacitation-induced tyrosine phosphorylation. Sperm from mice lacking ROPN1 had reduced levels of FSCB and increased tyrosine phosphorylation of noncapacitated sperm. These data demonstrate that mutations in ROPN1 and ROPN1L can cause defects in FS integrity, sperm motility, and PKA-dependent signaling processes, leading to male infertility.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/deficiencia , Axonema/fisiología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Proteínas de la Membrana/deficiencia , Motilidad Espermática/fisiología , Cola del Espermatozoide/fisiología , Proteínas de Unión al GTP rho/deficiencia , Proteínas de Anclaje a la Quinasa A/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/fisiología , Animales , Infertilidad Masculina/metabolismo , Infertilidad Masculina/fisiopatología , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/fisiología , Ratones , Ratones Noqueados , Modelos Animales , Fosforilación/fisiología , Transducción de Señal/fisiología , Capacitación Espermática/fisiología , Tirosina/metabolismo , Proteínas de Unión al GTP rho/genética , Proteínas de Unión al GTP rho/fisiología
14.
Rheumatology (Oxford) ; 52(11): 1952-62, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23804219

RESUMEN

OBJECTIVES: HLA-B*27:05 is associated with AS whereas HLA-B*27:09 is not associated. We hypothesized that different interactions with KIR immune receptors could contribute to the difference in disease association between HLA-B*27:05 and HLAB*27:09. Thus, the objective of this study was to compare the formation of ß2m-free heavy chain (FHC) including B27 dimers (B272) by HLA-B*27:05 and HLA-B*27:09 and their binding to KIR immunoreceptors. METHODS: We studied the formation of HLA-B*27:05 and HLA-B*27:09 heterotrimers and FHC forms including dimers in vitro and in transfected cells. We investigated HLA-B*27:05 and HLA-B*27:09 binding to KIR3DL1, KIR3DL2 and LILRB2 by FACS staining with class I tetramers and by quantifying interactions with KIR3DL2CD3ε-reporter cells and KIR3DL2-expressing NK cells. We also measured KIR expression on peripheral blood NK and CD4 T cells from 18 HLA-B*27:05 AS patients, 8 HLA-B27 negative and 12 HLA-B*27:05+ and HLA-B*27:09+ healthy controls by FACS staining. RESULTS: HLA-B*27:09 formed less B272 and FHC than HLA-B*27:05. HLA-B*27:05-expressing cells stimulated KIR3DL2CD3ε-reporter T cells more effectively. Cells expressing HLA-B*27:05 promoted KIR3DL2+ NK cell survival more strongly than HLA-B*27:09. HLA-B*27:05 and HLA-B*27:09 dimer tetramers stained KIR3DL1, KIR3DL2 and LILRB2 equivalently. Increased proportions of NK and CD4 T cells expressed KIR3DL2 in HLA-B*27:05+ AS patients compared with HLA-B*27:05+, HLA-B*27:09+ and HLA-B27- healthy controls. CONCLUSION: Differences in the formation of FHC ligands for KIR3DL2 by HLA-B*27:05 and HLA-B*27:09 could contribute to the differential association of these alleles with AS.


Asunto(s)
Antígeno HLA-B27/metabolismo , Cadenas Pesadas de Inmunoglobulina/metabolismo , Receptores KIR3DL2/metabolismo , Espondilitis Anquilosante/genética , Adulto , Alelos , Linfocitos T CD4-Positivos/inmunología , Supervivencia Celular/inmunología , Células Cultivadas , Técnicas de Cocultivo , Femenino , Predisposición Genética a la Enfermedad , Antígeno HLA-B27/genética , Humanos , Células Asesinas Naturales/inmunología , Ligandos , Masculino , Persona de Mediana Edad , Espondilitis Anquilosante/inmunología , Espondilitis Anquilosante/metabolismo , Transfección
15.
NPJ Vaccines ; 7(1): 76, 2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35790739

RESUMEN

We present the long-term outcomes of 44 patients who developed cerebral venous sinus thrombosis after vaccination with the adenoviral vector ChAdOx1 nCoV-19 COVID-19 vaccine. Assessment of the Extended Glasgow Outcome Scale was performed within 3-6 months after the initial hospital admissions. Patient outcomes ranged from good recovery (13 patients, 29.6%) to moderate disability (11 patients, 25.0%) and severe disability or vegetative state (6 patients, 13.6%). Fatal outcomes were reported in 14 patients (31.8%).

16.
J Am Chem Soc ; 133(12): 4645-54, 2011 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-21366243

RESUMEN

The proteorhodopsin (PR) family found in bacteria near the ocean's surface consists of hundreds of PR variants color-tuned to their environment. PR contains a highly conserved single histidine at position 75, which is not found in most other retinal proteins. Using (13)C and (15)N MAS NMR, we were able to prove for green PR that His75 forms a pH-dependent H-bond with the primary proton acceptor Asp97, which explains its unusually high pK(a). The functional role of His75 has been studied using site-directed mutagenesis and time-resolved optical spectroscopy: Ultrafast vis-pump/vis-probe experiments on PR(H75N) showed that the primary reaction dynamics is retained, while flash photolysis experiments revealed an accelerated photocycle. Our data show the formation of a pH-dependent His-Asp cluster which might be typical for eubacterial retinal proteins. Despite its stabilizing function, His75 was found to slow the photocycle in wild-type PR. This means that PR was not optimized by evolution for fast proton transfer, which raises questions about its true function in vivo.


Asunto(s)
Ácido Aspártico/química , Histidina/química , Rodopsina/química , Color , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética/normas , Modelos Moleculares , Estándares de Referencia , Rodopsinas Microbianas
17.
PLoS One ; 16(12): e0261496, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34937069

RESUMEN

Clinical studies on the efficacy of sonic toothbrushes show inconsistent results, most studies have been conducted without sufficient supervision of appropriate toothbrush usage. Aims of the explorative clinical trial were therefore to investigate whether the usage of an activated sonic toothbrush reduces plaque more effectively than an inactivated one used as a manual toothbrush, and to which extent the correct use of such toothbrush plays a role in its efficacy. The clinical trial was designed as a video-controlled interventional study. Thirty participants (mean (±SD) age 22.9 (±2.5) years) were included, areas of interest were the buccal surfaces of the upper premolars and the first molar (partial mouth recording). Toothbrushing was performed without toothpaste in a single brushing exercise under four different conditions: switched off, habitually used as manual toothbrush, no instruction; switched on, habitually used as powered toothbrush, no instruction; switched off, used as manual toothbrush, instruction in the Modified Bass Technique; switched on, used as powered toothbrush, instruction in a specific technique for sonic toothbrushes. Brushing performance was controlled by videotaping, plaque was assessed at baseline (after 4 days without toothbrushing) using the Rustogi modified Navy-Plaque-Index and planimetry. Main study results were that plaque decreased distinctly after habitual brushing regardless of using the sonic brush in ON or OFF mode (p for all comparisons < 0.001). After instruction, participants were able to use the sonic brush in ON mode as intended, with only minor impact on efficacy. Using the toothbrush in OFF mode with the Modified Bass Technique was significantly less effective than all other conditions (p for all comparisons < 0.001). Under the conditions used, the sonic toothbrush was not more effective when switched on than when switched off, and there was no evidence that the correct use of the toothbrush was more effective than the habitual use.


Asunto(s)
Índice de Placa Dental , Gingivitis , Cepillado Dental/instrumentación , Adulto , Femenino , Gingivitis/diagnóstico , Gingivitis/prevención & control , Humanos , Masculino , Estudios Prospectivos , Sonido , Cepillado Dental/métodos , Grabación en Video , Adulto Joven
18.
Cell Motil Cytoskeleton ; 65(7): 539-52, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18421703

RESUMEN

A-kinase anchoring proteins (AKAPs) bind to protein kinase A (PKA) via an amphipathic helix domain that interacts with a dimerization/docking domain on the regulatory (R) subunit of PKA. Four other mammalian proteins (ROPN1, ASP, SP17, and CABYR) also contain a highly conserved RII dimerization/docking (R2D2) domain, suggesting all four proteins may interact with all AKAPs in a manner similar to RII. All four of these proteins were originally detected in the flagellum of mammalian sperm. In this report, we demonstrate that all four R2D2 proteins are expressed in a wide variety of tissues and three of the proteins SP17, CABYR, and ASP are located in motile cilia of human bronchus and fallopian tubes. In addition, we detect SP17 in primary cilia. We also provide evidence that ROPN1 and ASP bind to a variety of AKAPs and this interaction can be disrupted with anchoring inhibitor peptides. The interaction of SP17 and CABYR with AKAPs appears to be much more limited. None of the R2D2 proteins appears to bind cAMP, a fundamental characteristic of the regulatory subunits of PKA. These observations suggest that R2D2 proteins utilize docking interactions with AKAPs to accomplish their function of regulating cilia and flagella. Based on location, affinity for AKAPs and lack of affinity for cAMP, it appears that each R2D2 protein has a unique role in this process.


Asunto(s)
Proteínas de Anclaje a la Quinasa A/metabolismo , Subunidad RIIalfa de la Proteína Quinasa Dependiente de AMP Cíclico/metabolismo , Proteínas de Anclaje a la Quinasa A/genética , Secuencia de Aminoácidos , Animales , Antígenos de Superficie/genética , Antígenos de Superficie/metabolismo , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Proteínas de Unión a Calmodulina , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Cilios/metabolismo , Cilios/ultraestructura , AMP Cíclico/metabolismo , Subunidad RIIalfa de la Proteína Quinasa Dependiente de AMP Cíclico/genética , Femenino , Humanos , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Filogenia , Estructura Terciaria de Proteína , Alineación de Secuencia , Cola del Espermatozoide/metabolismo , Cola del Espermatozoide/ultraestructura , Distribución Tisular , Proteínas de Unión al GTP rho/genética , Proteínas de Unión al GTP rho/metabolismo
19.
Mol Neurobiol ; 55(7): 6037-6049, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29143287

RESUMEN

Lipoic acid (LA) exhibits antioxidant and anti-inflammatory properties; supplementation reduces disease severity and T lymphocyte migration into the central nervous system in a murine model of multiple sclerosis (MS), and administration in secondary progressive MS (SPMS) subjects reduces brain atrophy compared to placebo. The mechanism of action (MOA) of LA's efficacy in suppression of MS pathology is incompletely understood. LA stimulates production of the immunomodulator cyclic AMP (cAMP) in vitro. To determine whether cAMP could be involved in the MOA of LA in vivo, we performed a clinical trial to examine whether LA stimulates cAMP production in healthy control and MS subjects, and whether there are differences in the bioavailability of LA between groups. We administered 1200 mg of oral LA to healthy control, relapsing remitting MS (RRMS) and SPMS subjects, and measured plasma LA and cAMP levels in peripheral blood mononuclear cells (PBMCs). There were no significant differences between the groups in pharmacokinetic (PK) parameters. Healthy and SPMS subjects had increased cAMP at 2 and 4 h post-LA treatment compared to baseline, while RRMS subjects showed decreases in cAMP. Additionally, plasma concentrations of prostaglandin E2 (PGE2, a known cAMP stimulator) were significantly lower in female RRMS subjects compared to female HC and SPMS subjects 4 h after LA ingestion. These data indicate that cAMP could be part of the MOA of LA in SPMS, and that there is a divergent response to LA in RRMS subjects that may have implications in the efficacy of immunomodulatory drugs. This clinical trial, "Defining the Anti-inflammatory Role of Lipoic Acid in Multiple Sclerosis," NCT00997438, is registered at https://clinicaltrials.gov/ct2/show/record/NCT00997438 .


Asunto(s)
AMP Cíclico/biosíntesis , Esclerosis Múltiple Crónica Progresiva/tratamiento farmacológico , Esclerosis Múltiple Crónica Progresiva/metabolismo , Ácido Tióctico/uso terapéutico , Administración Oral , Adulto , Anciano , Dinoprostona/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Esclerosis Múltiple Crónica Progresiva/sangre , Esclerosis Múltiple Crónica Progresiva/patología , Albúmina Sérica/metabolismo , Ácido Tióctico/sangre , Ácido Tióctico/farmacocinética , Ácido Tióctico/farmacología , Factor de Necrosis Tumoral alfa/sangre
20.
J Syst Integr Neurosci ; 3(3)2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28966794

RESUMEN

OBJECTIVE AND DESIGN: The etiology of multiple sclerosis (MS) is unknown, but blood derived monocytes/macrophages are believed to be involved in the pathogenesis through phagocytosis of myelin and production of inflammatory mediators. The objective of this study is to examine inflammatory cytokines that are present at elevated levels in active MS lesions to determine whether there are differences between classically stimulated monocytes isolated from healthy control (HC) and relapsing-remitting MS (RRMS) subjects taking disease modifying drugs (DMDs), including dimethyl fumarate (DMF). SUBJECTS: Thirty-nine veterans of the US Armed Forces were enrolled, 21 health controls (HC), and 18 with relapsing-remitting MS (RRMS), all taking DMDs. METHODS: Use ELISAs to measure production of IL-6, IL-1ß and TNF-α by LPS-stimulated peripheral monocytes. RESULTS: Activation of monocytes from MS subjects produced significantly more IL-6 than healthy controls (49531 ± 20795 vs 10526 ± 4845), and IL-6 production trended higher in MS subjects taking DMF than those taking other DMDs (72186.9 ± 35156.2 vs 32585.8 ± 17135.4). There were no significant differences in IL-1ß or TNF-α secretion. CONCLUSIONS: Our data suggest that not all DMDs may provide disease modification by suppressing monocyte/macrophage production of pro-inflammatory mediators.

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