187 research outputs found
Mammalian E-type Cyclins Control Chromosome Pairing, Telomere Stability and CDK2 Localization in Male Meiosis
Loss of function of cyclin E1 or E2, important regulators of the mitotic cell cycle, yields viable mice, but E2-deficient males display reduced fertility. To elucidate the role of E-type cyclins during spermatogenesis, we characterized their expression patterns and produced additional deletions of Ccne1 and Ccne2 alleles in the germline, revealing unexpected meiotic functions. While Ccne2 mRNA and protein are abundantly expressed in spermatocytes, Ccne1 mRNA is present but its protein is detected only at low levels. However, abundant levels of cyclin E1 protein are detected in spermatocytes deficient in cyclin E2 protein. Additional depletion of E-type cyclins in the germline resulted in increasingly enhanced spermatogenic abnormalities and corresponding decreased fertility and loss of germ cells by apoptosis. Profound meiotic defects were observed in spermatocytes, including abnormal pairing and synapsis of homologous chromosomes, heterologous chromosome associations, unrepaired double-strand DNA breaks, disruptions in telomeric structure and defects in cyclin-dependent-kinase 2 localization. These results highlight a new role for E-type cyclins as important regulators of male meiosis
Interventions to Increase Follow-Up of Abnormal Cervical Cancer Screening Results: A Systematic Literature Review and Meta-Analysis
INTRODUCTION: Ensuring timely follow-up of abnormal screening results is essential for eliminating cervical cancer.
OBJECTIVE: The purpose of the study was to review single and multicomponent interventions designed to improve follow-up of women with abnormal cervical cancer screening results. We report on effectiveness across studies, and describe what aspects of these interventions might be more impactful.
METHODS: Publications were searched between January 2000 and December 2022. The search included observational, quasi-experimental (pre-post studies) and randomized controlled studies describing at least one intervention to increase follow-up of women with abnormal cervical cancer screening results. Outcomes of studies included completion of any follow-up (i.e., attending a follow-up appointment), timely diagnosis (i.e., colposcopy results within 90 days of screening) and time to diagnostic resolution (i.e., days between screening and final diagnosis). We assessed risk of bias for observational and quasi-experimental studies using the Newcastle-Ottawa Scale (NOS) tool and the Cochrane collaboration tool for randomized studies. We conducted a meta-analysis using studies where data were provided to estimate a summary average effect of the interventions on follow-up of patients and to identify characteristics of studies associated with an increased effectiveness of interventions. We extracted the comparison and intervention proportions of women with follow-up before and after the intervention (control and intervention) and plotted the odds ratios (ORs) of completing follow-up along with the 95% confidence intervals (CIs) using forest plots for the interventions vs. controls when data were available.
FINDINGS: From 7,457 identified studies, 28 met the inclusion criteria. Eleven (39%) of the included studies had used a randomized design. Most studies (63%) assessed completion of any follow-up visit as the primary outcome, whereas others measured time to definite diagnosis (15%) or diagnostic resolution (22%). Navigation was used as a type of intervention in 63% of the included studies. Most interventions utilized behavioral approaches to improve outcomes. The overall estimate of the OR for completion of follow-up for all interventions was 1.81 (1.36-2.42). The highest impact was for programs using more than one approach (multicomponent interventions) to improve outcomes with OR = 3.01 (2.03-4.46), compared with studies with single intervention approaches with OR = 1.56 (1.14-2.14). No statistical risks were noted from publication bias or small-study effects in the studies reviewed.
CONCLUSION: Our findings revealed large heterogeneity in how follow-up of abnormal cervical cancer screening results was defined. Our results suggest that multicomponent interventions were more effective than single component interventions and should be used to improve follow-up after abnormal cervical cancer screening results. Navigation appears to be an important tool for improving follow-up. We also provide recommendations for future studies and implications for policy in terms of better defining outcomes for these interventions
Transplantation of Pro-Oligodendroblasts, Preconditioned by LPS-Stimulated Microglia, Promotes Recovery After Acute Contusive Spinal Cord Injury
Spinal cord injury (SCI) is a significant clinical challenge, and to date no effective treatment is available. Oligodendrocyte progenitor cell (OPC) transplantation has been a promising strategy for SCI repair. However, the poor posttransplantation survival and deficiency in differentiation into myelinating oligodendrocytes (OLs) are two major challenges that limit the use of OPCs as donor cells. Here we report the generation of an OL lineage population [i.e., pro-oligodendroblasts (proOLs)] that is relatively more mature than OPCs for transplantation after SCI. We found that proOLs responded to lipopolysaccharide (LPS)-stimulated microglia conditioned medium (L+M) by preserving toll-like receptor 4 (TLR4) expression, improving cell viability, and enhancing the expression of a myelinating OL marker myelin basic protein (MBP), compared to other OL lineage cells exposed to either LPS-stimulated (L+M) or nonstimulated microglia conditioned medium (L−M). When L+M-stimulated proOLs were intrathecally delivered through a lumbar puncture after a T10 thoracic contusive SCI, they promoted behavioral recovery, as assessed by the Basso‐Beattie‐Bresnahan (BBB) locomotor rating scale, stride length, and slips on the grid tests. Histologically, transplantation of L+M proOLs caused a considerable increase in intralesional axon numbers and myelination, and less accumulation of invading macrophages when compared with the vehicle control or OPC transplantation. Thus, transplantation of proOLs, preconditioned by L+M, may offer a better therapeutic potential for SCI than OPCs since the former may have initiated the differentiation process toward OLs prior to transplantation
A value-based network analysis for stakeholder engagement through prefabricated construction life cycle: evidence from China
Brief Report: Improving Early Infant Diagnosis Observations: Estimates of Timely HIV Testing and Mortality Among HIV-Exposed Infants.
BACKGROUND: Improving efforts toward elimination of mother-to-child transmission of HIV requires timely early infant diagnosis (EID) among all HIV-exposed infants, but the occurrence of timely EID and infant survival may be underascertained in routine, facility-bound program data. METHODS: From March 2015 to May 2015, we traced a random sample of HIV-positive mother and HIV-exposed infant pairs lost to follow-up for EID in facility registers in Zimbabwe. We incorporated updated information into weighted survival analyses to estimate incidence of EID and death. Reasons for no EID were surveyed from caregivers. RESULTS: Among 2651 HIV-positive women attending antenatal care, 1823 (68.8%) infants had no documented EID by 3 months of age. Among a random sample of 643 (35.3%) HIV-exposed infants lost to follow-up for EID, vital status was ascertained among 371 (57.7%) and updated care status obtained from 256 (39.8%) mothers traced. Among all HIV-infected mother-HIV-exposed infant pairs, weighted estimates found cumulative incidence of infant death by 90 days of 3.9% (95% confidence interval: 3.4% to 4.4%). Cumulative incidence of timely EID with death as a competing risk was 60%. The most frequently cited reasons for failure to uptake EID were "my child died" and "I didn't know I should have my child tested." CONCLUSIONS: Our findings indicate uptake of timely EID among HIV-exposed infants is underestimated in routine health information systems. High, early mortality among HIV-exposed infants underscores the need to more effectively identify HIV-positive mother-HIV exposed infant pairs at high risk of adverse outcomes and loss to follow-up for enhanced interventions
Proyecto CO-TRADE
Actualmente una gran cantidad de personas están interesadas en realizar negocios internacionales, a pesar de esto existe un alto grado de dificultad para que estas personas puedan tener acceso a cotizaciones rápidas. Co-Trade busca solucionar este problema, este proyecto consta en una plataforma que permite realizar cotizaciones rápidas y precisas, el objetivo principal de esta plataforma es reducir el tiempo de envío de las cotizaciones y permitir que se tenga un acceso más fácil a este tipo de cotizaciones. Para el desarrollo del proyecto se validó el problema planteado mediante una serie de experimentos que incluyeron entrevistas a expertos y entrevistas a personas del público objetivo. Posteriormente se desarrollaron herramientas como el Value Proposition Canvas y el Business Model Canvas para poder desarrollar un perfil del usuario e identificar la estructura del proyecto, después de esto se validó la solución mediante experimentos donde se expuso un prototipo del proyecto. Un punto fundamental en el desarrollo del proyecto fue la validación de la experiencia del usuario, en esta se realizaron entrevistas a profundidad, focus group y formularios virtuales para poder tener la opinión de una mayor cantidad de usuarios.Otro punto clave fue la validación del modelo de negocio, en esta mediante distintos experimentos se validaron los cuadrantes del BMC, se tuvo una validación con usuarios y expertos.
Finalmente, se desarrolló el plan de ejecución del concierge y la simulación de ventas, en este plan se identificó la cantidad de usuarios que estaban dispuestos a pagar por la aplicación y se concretaron ciertas ventas del proyecto, estas ventas fueron usadas para el desarrollo del plan financiero donde se pudo concluir de que el desarrollo del proyecto es viable financieramente.Currently a large number of people are interested in doing international business, despite this, there is a high degree of difficulty for these people to have access to quick quotes. Co-Trade seeks to solve this problem, this project consists of a platform that allows make quick and accurate quotes, the main objective of this platform is to reduce the delivery time of quotes and allow easier access to these types of quotes. For the development of the project, the problem posed was validated through a series of experiments that included interviews with experts and interviews with people from the target audience. Later tools such as the Value Proposition Canvas and the Business Model Canvas to be able to develop a user profile and identify the structure of the project, after this, the solution was validated through experiments where a prototype of the draft.
A fundamental point in the development of the project was the validation of the experience of the user, in this, in-depth interviews, focus groups and virtual forms were carried out to being able to have the opinion of a greater number of users. Another key point was the validation of the business model, in this through different experiments the BMC quadrants were validated, there was a validation with users and experts.
Finally, the concierge execution plan and the sales simulation were developed, in this plan the number of users who were willing to pay for the application was identified and certain sales of the project were made, these sales were used for the development of the plan where it was concluded that the development of the project is financially viable.Trabajo de investigació
Mutations in protocadherin 15 and cadherin 23 affect tip links and mechanotransduction in mammalian sensory hair cells
Immunocytochemical studies have shown that protocadherin-15 (PCDH15) and cadherin-23 (CDH23) are associated with tip links, structures thought to gate the mechanotransducer channels of hair cells in the sensory epithelia of the inner ear. The present report describes functional and structural analyses of hair cells from Pcdh15av3J (av3J), Pcdh15av6J (av6J) and Cdh23v2J (v2J) mice. The av3J and v2J mice carry point mutations that are predicted to introduce premature stop codons in the transcripts for Pcdh15 and Cdh23, respectively, and av6J mice have an in-frame deletion predicted to remove most of the 9th cadherin ectodomain from PCDH15. Severe disruption of hair-bundle morphology is observed throughout the early-postnatal cochlea in av3J/av3J and v2J/v2J mice. In contrast, only mild-to-moderate bundle disruption is evident in the av6J/av6J mice. Hair cells from av3J/av3J mice are unaffected by aminoglycosides and fail to load with [3H]-gentamicin or FM1-43, compounds that permeate the hair cell's mechanotransducer channels. In contrast, hair cells from av6J/av6J mice load with both FM1-43 and [3H]-gentamicin, and are aminoglycoside sensitive. Transducer currents can be recorded from hair cells of all three mutants but are reduced in amplitude in all mutants and have abnormal directional sensitivity in the av3J/av3J and v2J/v2J mutants. Scanning electron microscopy of early postnatal cochlear hair cells reveals tip-link like links in av6J/av6J mice, substantially reduced numbers of links in the av3J/av3J mice and virtually none in the v2J/v2J mice. Analysis of mature vestibular hair bundles reveals an absence of tip links in the av3J/av3J and v2J/v2J mice and a reduction in av6J/av6J mice. These results therefore provide genetic evidence consistent with PCDH15 and CDH23 being part of the tip-link complex and necessary for normal mechanotransduction
Chemical intervention in plant sugar signalling increases yield and resilience
The pressing global issue of food insecurity due to population growth, diminishing land and variable climate can only be addressed in agriculture by improving both maximum crop yield potential and resilience. Genetic modification is one potential solution, but has yet to achieve worldwide acceptance, particularly for crops such as wheat. Trehalose-6-phosphate (T6P), a central sugar signal in plants, regulates sucrose use and allocation, underpinning crop growth and development. Here we show that application of a chemical intervention strategy directly modulates T6P levels in planta. Plant-permeable analogues of T6P were designed and constructed based on a ‘signalling-precursor’ concept for permeability, ready uptake and sunlight-triggered release of T6P in planta. We show that chemical intervention in a potent sugar signal increases grain yield, whereas application to vegetative tissue improves recovery and resurrection from drought. This technology offers a means to combine increases in yield with crop stress resilience. Given the generality of the T6P pathway in plants and other small-molecule signals in biology, these studies suggest that suitable synthetic exogenous small-molecule signal precursors can be used to directly enhance plant performance and perhaps other organism function
Gut Microbiome Dysbiosis in Antibiotic-Treated COVID-19 Patients is Associated with Microbial Translocation and Bacteremia
Although microbial populations in the gut microbiome are associated with COVID-19 severity, a causal impact on patient health has not been established. Here we provide evidence that gut microbiome dysbiosis is associated with translocation of bacteria into the blood during COVID-19, causing life-threatening secondary infections. We first demonstrate SARS-CoV-2 infection induces gut microbiome dysbiosis in mice, which correlated with alterations to Paneth cells and goblet cells, and markers of barrier permeability. Samples collected from 96 COVID-19 patients at two different clinical sites also revealed substantial gut microbiome dysbiosis, including blooms of opportunistic pathogenic bacterial genera known to include antimicrobial-resistant species. Analysis of blood culture results testing for secondary microbial bloodstream infections with paired microbiome data indicates that bacteria may translocate from the gut into the systemic circulation of COVID-19 patients. These results are consistent with a direct role for gut microbiome dysbiosis in enabling dangerous secondary infections during COVID-19
Tracking smell loss to identify healthcare workers with SARS-CoV-2 infection
Introduction Healthcare workers (HCW) treating COVID-19 patients are at high risk for infection and may also spread infection through their contact with vulnerable patients. Smell loss has been associated with SARS-CoV-2 infection, but it is unknown whether monitoring for smell loss can be used to identify asymptomatic infection among high risk individuals. In this study we sought to determine if tracking smell sensitivity and loss using an at-home assessment could identify SARS-CoV-2 infection in HCW. Methods and findings We performed a prospective cohort study tracking 473 HCW across three months to determine if smell loss could predict SARS-CoV-2 infection in this high-risk group. HCW subjects completed a longitudinal, behavioral at-home assessment of olfaction with household items, as well as detailed symptom surveys that included a parosmia screening questionnaire, and real-time quantitative polymerase chain reaction testing to identify SARS-CoV-2 infection. Our main measures were the prevalence of smell loss in SARS-CoV-2-positive HCW versus SARS-CoV- 2-negative HCW, and timing of smell loss relative to SARS-CoV-2 test positivity. SARS-CoV-2 was identified in 17 (3.6%) of 473 HCW. HCW with SARS-CoV-2 infection were more likely to report smell loss than SARS-CoV-2-negative HCW on both the at-home assessment and the screening questionnaire (9/17, 53% vs 105/456, 23%, P < .01). 6/9 (67%) of SARS-CoV-2-positive HCW reporting smell loss reported smell loss prior to having a positive SARS-CoV-2 test, and smell loss was reported a median of two days before testing positive. Neurological symptoms were reported more frequently among SARS-CoV-2-positive HCW who reported smell loss compared to those without smell loss (9/9, 100% vs 3/8, 38%, P < .01). Conclusions In this prospective study of HCW, self-reported changes in smell using two different measures were predictive of SARS-CoV-2 infection. Smell loss frequently preceded a positive test and was associated with neurological symptoms
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