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1.
Proc Natl Acad Sci U S A ; 120(3): e2215071120, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36623192

RESUMEN

CAG trinucleotide repeat expansions cause several neurodegenerative diseases, including Huntington's disease and spinocerebellar ataxia. RNAs with expanded CAG repeats contribute to disease in two unusual ways. First, these repeat-containing RNAs may agglomerate in the nucleus as foci that sequester several RNA-binding proteins. Second, these RNAs may undergo aberrant repeat-associated non-AUG (RAN) translation in multiple frames and produce aggregation-prone proteins. The relationship between RAN translation and RNA foci, and their relative contributions to cellular dysfunction, are unclear. Here, we show that CAG repeat-containing RNAs that undergo RAN translation first accumulate at nuclear foci and, over time, are exported to the cytoplasm. In the cytoplasm, these RNAs are initially dispersed but, upon RAN translation, aggregate with the RAN translation products. These RNA-RAN protein agglomerates sequester various RNA-binding proteins and are associated with the disruption of nucleocytoplasmic transport and cell death. In contrast, RNA accumulation at nuclear foci alone does not produce discernable defects in nucleocytoplasmic transport or cell viability. Inhibition of RAN translation prevents cytoplasmic RNA aggregation and alleviates cell toxicity. Our findings demonstrate that RAN translation-induced RNA-protein aggregation correlates with the key pathological hallmarks observed in disease and suggest that cytoplasmic RNA aggregation may be an underappreciated phenomenon in CAG trinucleotide repeat expansion disorders.


Asunto(s)
Enfermedad de Huntington , Ataxias Espinocerebelosas , Humanos , ARN/genética , Expansión de Repetición de Trinucleótido/genética , Ataxias Espinocerebelosas/genética , Enfermedad de Huntington/genética
2.
J Pediatr Orthop ; 44(6): 366-372, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38595095

RESUMEN

OBJECTIVE: Severe spinal deformity results in restrictive pulmonary disease from thoracic distortions and lung-volume limitations. Though spirometry and body plethysmography are widely accepted tests for pulmonary function tests (PFTs), they are time-consuming and require patient compliance. This study investigates whether surface topographic [surface topography (ST)] measurements of body volume difference (BVD) and torso volume difference between maximum inhale and exhale correlate to values determined on PFTs. METHODS: This study included patients with idiopathic scoliosis and thoracic/thoracolumbar curves ≥40 degrees. Patients received ST scans, clinical examinations, and EOS biplanar radiographs on the same day. PFTs were performed within 3 months of ST/radiographic analysis. Univariate linear regression analysis was used to examine relationships between BVD, PFT values, and mean curves. RESULTS: Sixteen patients (14.6 ± 2.2 y, 69% females) with idiopathic scoliosis and mean thoracic/thoracolumbar curves of 62 degrees ± 15˚ degrees (45 degrees to 93 degrees) were assessed. BVD displayed statistically high-positive positive correlations with forced vital capacity ( R = 0.863, P < 0.0001), forced expiratory volume in 1 second ( R = 0.870, P < 0.001), vital capacity ( R = 0.802, P < 0.0001), and TLC ( R = 0.831, P < 0.0001. Torso volume difference showed similarly high positive correlations to forced vital capacity, forced expiratory volume in 1 second, vital capacity, and TLC, but not residual volume. No correlations emerged between the mean thoracic/thoracolumbar curve and BVD or PFT values. CONCLUSION: This study strongly endorses further investigation into ST scanning as an alternative to traditional PFTs for assessing pulmonary volumes. The noncontact and noninvasive nature of ST scanning presents a valuable alternative method for analyzing thoracic volume, particularly beneficial for patients unable to cooperate with standard PFTs. LEVEL OF EVIDENCE: Level II-prognostic.


Asunto(s)
Mediciones del Volumen Pulmonar , Pruebas de Función Respiratoria , Escoliosis , Humanos , Escoliosis/fisiopatología , Escoliosis/diagnóstico por imagen , Femenino , Masculino , Adolescente , Niño , Mediciones del Volumen Pulmonar/métodos , Pulmón/fisiopatología , Pulmón/diagnóstico por imagen , Espirometría/métodos
3.
J Pediatr Orthop ; 43(10): 608-614, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37599604

RESUMEN

BACKGROUND: Up to 75% of patients with idiopathic scoliosis (IS) report back pain, but the exact contributors are unclear. This study seeks to assess how pain correlates with demographics, radiographic and surface topographic (ST) measurements, and patient-reported outcome measures (PROMs) in patients with IS. METHODS: Patient-Reported Outcome Measurement Information System (PROMIS) Pain Interference (PI) and Scoliosis Research Society revised (SRS-22r) pain domain from an IRB approved prospectively collected registry containing patients 11 to 21 years old with IS were correlated (Spearman coefficients) with measurements from whole-body EOS radiography and ST scanning, PROMIS 1.0 PROMs, Trunk Appearance Perception Scale (TAPS), and SRS-22r domains. SRS-22r and PROMIS-PI were also compared between different sex, scoliosis severities, and primary curve locations with Mann-Whitney U or Kruskal-Wallis tests, and if significant differences were found, included with the 5 highest univariate correlated variables into stepwise multivariate linear regression models ( P <0.05 to enter, P >0.1 to remove) predicting SRS-22r pain and PROMIS-PI. RESULTS: One hundred and forty-nine patients (14.5 ± 2.0 y, body mass index 20.6 ± 4.1 kg/m 2 , 96 (64%) female, mean major coronal curve 40 ± 19 deg, range: 10 deg, 83 deg) reported mean PROMIS-PI of 42.2 ± 10.0 and SRS-22r pain of 4.4 ± 0.6. SRS-22r self-image was the most correlated variable with both SRS-22r pain (rho=0.519) and PROMIS-PI (rho=-0.594). Five variables, none of which were ST or radiographic measures, strongly predicted SRS pain domain (R=0.711, R2=0.505, N=138). Two variables (SRS-22r self-image and SRS-22r function) were utilized by a model correlated with PROMIS-PI (R=0.687, R2=0.463, N=124). CONCLUSIONS: SRS-22r function and self-image domains were more strongly correlated with SRS-22r pain and PROMIS-PI than any radiographic or ST measurements. LEVEL OF EVIDENCE: Level II-retrospective study.

4.
Proc Natl Acad Sci U S A ; 116(18): 8895-8900, 2019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-31004062

RESUMEN

Alzheimer's disease (AD) is characterized by the deposition of ß-sheet-rich, insoluble amyloid ß-peptide (Aß) plaques; however, plaque burden is not correlated with cognitive impairment in AD patients; instead, it is correlated with the presence of toxic soluble oligomers. Here, we show, by a variety of different techniques, that these Aß oligomers adopt a nonstandard secondary structure, termed "α-sheet." These oligomers form in the lag phase of aggregation, when Aß-associated cytotoxicity peaks, en route to forming nontoxic ß-sheet fibrils. De novo-designed α-sheet peptides specifically and tightly bind the toxic oligomers over monomeric and fibrillar forms of Aß, leading to inhibition of aggregation in vitro and neurotoxicity in neuroblastoma cells. Based on this specific binding, a soluble oligomer-binding assay (SOBA) was developed as an indirect probe of α-sheet content. Combined SOBA and toxicity experiments demonstrate a strong correlation between α-sheet content and toxicity. The designed α-sheet peptides are also active in vivo where they inhibit Aß-induced paralysis in a transgenic Aß Caenorhabditis elegans model and specifically target and clear soluble, toxic oligomers in a transgenic APPsw mouse model. The α-sheet hypothesis has profound implications for further understanding the mechanism behind AD pathogenesis.


Asunto(s)
Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/química , Estructura Secundaria de Proteína , Péptidos beta-Amiloides/metabolismo , Animales , Anticuerpos , Encéfalo/metabolismo , Encéfalo/patología , Caenorhabditis elegans , Humanos , Immunoblotting , Ratones , Agregado de Proteínas , Agregación Patológica de Proteínas
5.
Eur J Clin Microbiol Infect Dis ; 40(2): 361-371, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33179133

RESUMEN

An indirect in-house immunofluorescent assay was developed in order to assess the serological status of COVID-19 patients in Marseille, France. Performance of IFA was compared to a commercial ELISA IgG kit. We tested 888 RT-qPCR-confirmed COVID-19 patients (1302 serum samples) and 350 controls including 200 sera collected before the pandemic, 64 sera known to be associated with nonspecific serological interference, 36 sera from non-coronavirus pneumonia and 50 sera from patient with other common coronavirus to elicit false-positive serology. Incorporating an inactivated clinical SARS-CoV-2 isolate as the antigen, the specificity of the assay was measured as 100% for IgA titre ≥ 1:200, 98.6% for IgM titre ≥ 1:200 and 96.3% for IgG titre ≥ 1:100 after testing a series of negative controls. IFA presented substantial agreement (86%) with ELISA EUROIMMUN SARS-CoV-2 IgG kit (Cohen's Kappa = 0.61). The presence of antibodies was then measured at 3% before a 5-day evolution up to 47% after more than 15 days of evolution. We observed that the rates of seropositivity as well as the titre of specific antibodies were both significantly higher in patients with a poor clinical outcome than in patients with a favourable evolution. These data, which have to be integrated into the ongoing understanding of the immunological phase of the infection, suggest that detection anti-SARS-CoV-2 antibodies is useful as a marker associated with COVID-19 severity. The IFA assay reported here is useful for monitoring SARS-CoV-2 exposure at the individual and population levels.


Asunto(s)
Anticuerpos Antivirales/sangre , COVID-19/diagnóstico , Técnica del Anticuerpo Fluorescente Indirecta/métodos , SARS-CoV-2/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Adulto Joven
6.
AIDS Behav ; 24(12): 3436-3455, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32385678

RESUMEN

While oral pre-exposure prophylaxis (PrEP) has proven efficacious for HIV prevention, consistent use is necessary to achieve its intended impact. We compared effectiveness of enhanced PrEP (enPrEP) adherence support to standard of care (sPrEP) among Black MSM and TGW attending a community clinic in Harlem, NY. EnPrEP included peer navigation, in-person/online support groups, and SMS messages. Self-reported adherence over previous 30 days, collected in quarterly interviews, was defined as ≥ 57%. Crude and adjusted analyses examined factors associated with adherence. A total of 204 participants were enrolled and randomized; 35% were lost to follow-up. PrEP adherence was 30% at 12-months; no intervention effect was observed (p = 0.69). Multivariable regression analysis found that lower adherence was associated with low education and depressive symptoms. We found that an enhanced adherence intervention did not improve PrEP adherence. Findings point to the need for innovative methods to improve PrEP adherence among Black MSM and TGW.Clinical Trial Registration NCT02167386, June 19, 2014.


Asunto(s)
Infecciones por VIH , Profilaxis Pre-Exposición , Personas Transgénero , Negro o Afroamericano , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Humanos , Masculino , Cumplimiento de la Medicación , New York
7.
Epidemiol Infect ; 148: e79, 2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32299522

RESUMEN

During the 2017 European hepatitis A (HA) outbreak we assessed HA incidence in our cohort of 2300 HIV-infected patients, implemented preventive measures and evaluated practices and knowledge on sexually transmitted diseases (STD). HA incidence was assessed between 1 January 2017 and 31 December 2017 and included all symptomatic patients with virologically confirmed HA. Preventive measures consisted in identifying at risk and not immunised patients to propose them a free HAV vaccination, and an anonymous survey related to transmission routes of STD and to sexual behaviours. Twenty HA were diagnosed. All were homosexual men recently diagnosed with HIV and another STD. None were vaccinated against hepatitis A virus (HAV). Hospitalisation was required for 52%. We identified 250 patients at risk to acquire HAV and invited them to a free immunisation program. A total of 110 (44%) were vaccinated, of whom 74 responded to our survey. A majority of them (84%) reported recent active anal and oral sexuality with multiple (52%) male partners (81%), and ChemSex consumption (14%). Internet was the meeting link for 58%. Another STD history was found in 69%. One third of these individuals had no idea about STD transmission modes. This HA outbreak pointed the insufficient vaccine coverage against HAV and knowledge on STD, which may be improved by Internet.


Asunto(s)
Coinfección/epidemiología , Brotes de Enfermedades , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Hepatitis A/complicaciones , Hepatitis A/epidemiología , Adulto , Bisexualidad , Francia/epidemiología , Homosexualidad Masculina , Humanos , Masculino , Persona de Mediana Edad
8.
Vox Sang ; 113(2): 136-142, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29082579

RESUMEN

BACKGROUND AND OBJECTIVES: Haemoglobin threshold for transfusion has been significantly decreased, but haemoglobin plasma concentration may not be sufficient to assess the need of red-blood-cell (RBC) transfusion. Central venous oxygen saturation (ScvO2 ) is a clue of metabolic matching between O2 transport and consumption, which could help to assess when transfusion is appropriate once anaemia has been diagnosed in ICU patients. MATERIALS AND METHODS: Adult patients admitted consecutively to a cardiothoracic and vascular ICU were included in a prospective, observational and single-centre study over a 6-month period (September 2014 to February 2015), provided they were transfused with RBC. Patients with active bleeding or in unstable condition were excluded. Haemoglobin and ScvO2 were collected through a central venous catheter before and after transfusion. In order to identify a ScvO2 threshold, analysis of ScvO2 changes after transfusion was performed. RESULTS: Fifty-three patients received 100 RBC transfusions. Haemoglobin at the time of transfusion was 7·2 g/dl [6·8-7·7], while ScvO2 was 66·9% [60-73]. A 5% increase in ScvO2 after transfusion has the best specificity and positive predictive values, with a ScvO2 threshold of 65%. After transfusion (RBC units, 2 [1-2]), ScvO2 increased only in patients with ScvO2 ≤65%, from 58% [53-62] to 69% [64-73] (P < 0·001). CONCLUSION: In anaemic patients, RBC transfusion induced a significant increase in ScvO2 , provided it was low before transfusion. A 65% cut-off value of ScvO2 before transfusion showed good specificity and good positive predictive value for a 5% increase after transfusion.


Asunto(s)
Anemia/terapia , Cuidados Críticos/métodos , Transfusión de Eritrocitos/métodos , Oxígeno/sangre , Anciano , Transfusión de Eritrocitos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxihemoglobinas/metabolismo
9.
Vox Sang ; 113(2): 120-127, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29238971

RESUMEN

BACKGROUND AND OBJECTIVES: A postauthorization safety study was performed between 2009 and 2012 to describe the use of Clottafact® in acquired fibrinogen deficiency in real-life medical practice in France. MATERIALS AND METHODS: One hundred and fifty patients were planned for 28 days of prospective follow-up after infusion. The analysis of this observational study was descriptive and performed according to the type of treatment (curative or preventive) and the origin of the bleed. RESULTS: One hundred and fifty-six patients (16-87 years) were included in 13 centres and treated in five different medical bleeding situations: postpartum (59), other gynaecological/obstetrical (6), trauma (34), liver (13), cardiovascular (23) and other various bleeding situations (21). The mean follow-up time was 18·9 ± 12·3 days. Two patients presented adverse drug reactions: one a pulmonary embolism and the other a four-site venous thromboembolic episode. All were serious with a dubious causal relationship with the study treatment. Efficacy data were collected as a secondary objective. In 150 patients receiving curative treatment, 117 of 159 infusions (73·6%) were considered as successful by the investigators, 35 as moderate (22%) and seven as no response (4·4%). CONCLUSION: The Clottafact® safety profile observed during the study matched the known profile of fibrinogen during use.


Asunto(s)
Afibrinogenemia/tratamiento farmacológico , Coagulantes/efectos adversos , Fibrinógeno/efectos adversos , Hemostáticos/efectos adversos , Adulto , Anciano , Coagulantes/administración & dosificación , Coagulantes/uso terapéutico , Femenino , Fibrinógeno/administración & dosificación , Fibrinógeno/uso terapéutico , Hemostáticos/administración & dosificación , Hemostáticos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
10.
Acta Virol ; 61(1): 123-126, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28161966

RESUMEN

Mimivirus was the first discovered amoebal giant virus. The Mimivirus virions are covered by a dense layer of approximately 130 nm-long fibers, the length and shape of which diverge from those of other viruses. Here, we aimed at expressing the L725 protein to further confirm and study its role as a fiber-associated protein. We report Escherichia coli expression of the L725 protein, which is encoded by a Mimivirus ORFan, was previously identified by proteomics in purified viral fibers and demonstrated to be a fiber-associated protein by RNA-silencing experiments. The expressed protein was recognized by anti-Mimivirus fiber or anti-Mimivirus L725 polyclonal antibodies. This study is the only expression, to our knowledge, of a product from a Mimiviral ORFan gene.


Asunto(s)
Regulación Viral de la Expresión Génica/fisiología , Mimiviridae/metabolismo , Proteínas Recombinantes , Proteínas Virales/metabolismo , Escherichia coli/metabolismo , Mimiviridae/genética , Proteínas Virales/genética
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