Morphological Effects of Cigarette Smoking on Respiratory System and Related Functions Based on AQPs Expression

SUMMARY: A great deal of attention of air pollution on respiratory health is increasing, particularly in relation to haze days. It is that exposure to cigarette smoke augments the toxicity of common air contaminants, thereby increasing the complexity of respiratory diseases. Although there are various mechanisms involved to respiratory diseases caused or worsen by cigarette smoking, in which the role of AQPs in the lung with regard to fluid homeostasis still remains elusive. In this paper, we copied the rat models based on smoke generator, and investigated the morphological changes of mucosa and related functions depending on the balance of lining liquid of alveoli via AQPs expression. Compared with normal group, weak labelling of AQP1 and AQP5 protein abundance were clearly detected in the corresponding part of smoke exposure groups compared with normal group. Hence, it is suggested that the contribution of AQPs in the lung is diminished, thereby causing perturbed balancing between resorptive and secretory fluid homeostasis under cigarette smoking.

Cada vez se presta más atención a la contaminación del aire en la salud respiratoria, particularmente, en relación con los días de neblina. En consecuencia la exposición al humo del cigarrillo aumenta la toxicidad de los contaminantes comunes del aire, lo que además aumenta la complejidad de las enfermedades respiratorias. Aunque existen varios mecanismos involucrados en las enfermedades respiratorias causadas o empeoradas por el tabaquismo, en las que el papel de las AQP en el pulmón respecto a la homeostasis de líquidos sigue siendo difícil de alcanzar. En este artículo, copiamos los modelos de rata basados en el generador de humo e investigamos los cambios morfológicos de la mucosa y las funciones relacionadas según el equilibrio del líquido de revestimiento de los alvéolos a través de la expresión de AQP. En comparación con el grupo normal, se detectó claramente un etiquetado débil de la abundancia de proteínas AQP1 y AQP5 en la parte correspondiente de los grupos de exposición al humo en comparación con el grupo control. Por lo tanto, se sugiere que la contribución de las AQP en el pulmón está disminuida, provocando así un equilibrio perturbado entre la homeostasis del líquido secretor y de reabsorción bajo el hábito de fumar cigarrillos.

Unlocking the secrets of saliva: the promising potential of salivary biomarkers for evaluating crack use / Desvendando os segredos da saliva: o potencial promissor dos biomarcadores salivares para avaliar o uso de crack

The forthcoming letter will encompass the following highlights: Crack cocaine use involves smoking a highly addictive form of cocaine, which is a significant concern in Brazil, particularly in urban areas. This addiction is linked to various health problems, including cardiovascular issues, sexually transmitted infections (STIs) like AIDS and syphilis, tuberculosis, and a notable increase in mortality, largely due to violent causes. Furthermore, crack cocaine users are particularly vulnerable to dental caries, gingival inflammation, oral mucosa lesions, and xerostomia (AU)

A próxima carta incluirá os seguintes destaques: O uso de crack envolve fumar uma forma altamente viciante da cocaína, o que é uma preocupação significativa no Brasil, especialmente em áreas urbanas. Esta dependência está ligada a vários problemas de saúde, incluindo problemas cardiovasculares, infecções sexualmente transmissíveis (IST), como a AIDS e a sífilis, a tuberculose e um aumento notável da mortalidade, devido, em grande parte, a causas violentas. Além disso, os usuários de crack são particularmente vulneráveis a cáries dentárias, inflamação gengival, lesões na mucosa oral e xerostomia (AU)

Identification of Human Body Fluid Stains and Non-Biological Stains by Three-Dimensional Fluorescence Spectroscopy / 法医学杂志

OBJECTIVES@#To establish a rapid and nondestructive identification method for human body fluid stains and non-biological stains using three-dimensional fluorescence spectroscopy.@*METHODS@#The collected three-dimensional fluorescence spectrum data of human saliva, 3% blood, coffee and Fanta® stains were processed with dimensionality reduction. After wavelet transform, spectral denoising and feature extraction, the classification formula was established. The Fisher discriminant was used for spectrum matching and recognition to establish the analysis method to distinguish stain types.@*RESULTS@#According to the results of data training and comparison, all the recognition accuracies of Fanta®, coffee, saliva and blood were more than 91.39%. Among them, saliva reached 100% recognition accuracy.@*CONCLUSIONS@#Three-dimensional fluorescence spectroscopy is a potential method for rapid and nondestructive identification of biological and non-biological stains.

Research Progress on Biological Matrix Reference Materials in Forensic Toxicology / 法医学杂志

Biological matrix reference material is a reference material that combines the target material with the biological matrix. The biological matrix reference material has higher consistency with the authentic specimens in forensic toxicology, and its application has a positive effect on improving the accuracy of test results. This paper reviews the research on the matrix reference materials corresponding to three common biological test materials (blood, urine and hair). In order to provide reference for the development and application of biological matrix reference materials in forensic toxicology, this paper mainly introduces the research progress of preparation technology of biological matrix reference materials and some existing products and their parameters evaluation.

Application and Prospect of RNA Profiling Analysis in Forensic Body Fluid Identification / 法医学杂志

In forensic physical evidence identification, the accurate identification of the individual origin and their body fluid composition of the biological samples obtained from the crime scene play a critical role in determining the nature of a crime. In recent years, RNA profiling has become one of the fastest developing methods for body fluids identification. Due to the characteristics of tissue or body fluid specific expression, various types of RNA markers have been proven to be promising candidate markers for body fluids identification in previous studies. This review summarizes the research progress of RNA markers in body fluids identification, including the RNA markers that have been effectively verified in current research and their advantages and disadvantages. Meanwhile, this review prospects the application of RNA markers in forensic medicine.

Application of Duplex Droplet Digital PCR Detection of miR-888 and miR-891a in Semen Identification / 法医学杂志

OBJECTIVES@#To establish a system for simultaneous detection of miR-888 and miR-891a by droplet digital PCR (ddPCR), and to evaluate its application value in semen identification.@*METHODS@#The hydrolysis probes with different fluorescence modified reporter groups were designed to realize the detection of miR-888 and miR-891a by duplex ddPCR. A total of 75 samples of 5 body fluids (including peripheral blood, menstrual blood, semen, saliva and vaginal secretion) were detected. The difference analysis was conducted by Mann-Whitney U test. The semen differentiation ability of miR-888 and miR-891a was evaluated by ROC curve analysis and the optimal cut-off value was obtained.@*RESULTS@#There was no significant difference between the dual-plex assay and the single assay in this system. The detection sensitivity was up to 0.1 ng total RNA, and the intra- and inter-batch coefficients of variation were less than 15%. The expression levels of miR-888 and miR-891a detected by duplex ddPCR in semen were both higher than those in other body fluids. ROC curve analysis showed that the AUC of miR-888 was 0.976, the optimal cut-off value was 2.250 copies/μL, and the discrimination accuracy was 97.33%; the AUC of miR-891a was 1.000, the optimal cut-off value was 1.100 copies/μL, and the discrimination accuracy was 100%.@*CONCLUSIONS@#In this study, a method for detection of miR-888 and miR-891a by duplex ddPCR was successfully established. The system has good stability and repeatability and can be used for semen identification. Both miR-888 and miR-891a have high ability to identify semen, and the discrimination accuracy of miR-891a is higher.

Cumplimiento de protocolos y técnicas de enfermería y exposición accidental a riesgos biológicos en estudiantes en las prácticas clínicas / Compliance with nursing protocols and techniques and accidental exposure to biological risks in students in clinical practices

La exposición a peligros biológicos para la salud y las medidas preventivas implementadas para evitar o minimizar esta exposición, es parcialmente desconocida en Ecuador; particularmente, por los estudiantes de enfermería, los cuales, durante sus prácticas pre-profesionales, están expuestos a factores que pueden afectar negativamente el bienestar en su lugar de trabajo. El riesgo puede ser de origen diversos, físicos, ergonómicos, químicos, psicosociales y biológicos. Entre los biológicos se incluyen pinchazos con agujas, salpicaduras de sangre y otros fluidos corporales, cortes de ampollas de medicamentos, cortes de bisturí, perforación de guantes durante la cirugía, contacto con la sangre de los pacientes con las manos sin guantes y contaminación de heridas abiertas con la sangre de los pacientes. Este estudio tuvo como objetivo establecer la relación entre el cumplimiento de los protocolos y técnicas de enfermería con la exposición accidental a riesgos biológicos en estudiantes. Los resultados demostraron asociación estadísticamente significativa entre las variables en estudios, evidenciándose que, a menor cumplimiento de los protocolos e inexperiencias en las maniobras técnicas de enfermería, mayor era la probabilidad a accidentes por riesgo biológico. Se concluye que el conocimiento de los protocolos de enfermería, la vigilancia sobre la prevención de infecciones, la adherencia a las normas de bioseguridad son algunas de las medidas a seguir para reducir la exposición de los estudiantes de enfermería a los riesgos laborales biológicos. Se recomienda, establecer sistemática para el reporte y abordaje de accidentes por riesgo biológicos que ocurran a los estudiantes de enfermería, durante su proceso formativo(AU)

Exposure to biological health hazards and the preventive measures implemented to avoid or minimize this exposure are partially unknown in Ecuador; particularly by nursing students, who, during their pre-professional practices, are exposed to factors that can negatively affect well-being in their workplace. The risk can be of various physical, ergonomic, chemical, psychosocial and biological origins. Biological include needle sticks, splashes of blood and other body fluids, cuts from medication blisters, scalpel cuts, perforation of gloves during surgery, contact with blood from patients on bare hands, and contamination of wounds opened with the blood of patients. This study aimed to establish the relationship between compliance with nursing protocols techniques and accidental exposure to biological risks in students. The results showed a statistically significant association between the variables in the studies, showing that, the less compliance with the protocols and inexperience in nursing technical maneuvers, the greater the probability of accidents due to biological risk. It is concluded that knowledge of nursing protocols, surveillance of infection prevention, adherence to biosafety standards are some of the measures to be followed to reduce the exposure of nursing students to biological occupational hazards. It is concluded that knowledge of nursing protocols, surveillance of infection prevention, adherence to biosafety standards are some of the measures to be followed to reduce the exposure of nursing students to biological occupational hazards. It is recommended to establish a system for reporting and addressing biological risk accidents that occur to nursing students during their training process(AU)

Teoria de médio alcance do risco de volume de líquidos excessivo / Teoría de rango medio del riesgo de un volumen de líquido excesivo / Excessive fluid volume risk middle-range theory

RESUMO Objetivo construir uma teoria de médio alcance para o desenvolvimento da proposição diagnóstica risco de volume de líquidos excessivo em pacientes em hemodiálise. Método trata-se de um estudo metodológico, desenvolvido para a validade teórico-causal de um diagnóstico de enfermagem. O estudo foi realizado em quatro etapas: seleção dos estudos, identificação dos conceitos principais da teoria, construção do pictograma e elaboração das proposições. Essas etapas foram operacionalizadas por meio de uma revisão integrativa da literatura, com uma amostra de 82 artigos selecionados nas bases de dados Web of Science, PubMed, CINAHL, Scopus e Science Direct. Resultados os dados extraídos dos artigos da amostra possibilitaram a identificação de cinco termos essenciais para a definição do risco de volume de líquidos excessivo. Além disso, foram identificados 31 fatores etiológicos do risco de volume de líquidos excessivo, além de construídos um pictograma e 12 proposições. Conclusão e implicações para a prática a construção de uma teoria de médio alcance voltada para o risco de volume de líquidos excessivo em pacientes em hemodiálise refina as terminologias e amplia a compreensão dos fenômenos da enfermagem. Assim, os dados desta pesquisa fornecerão conhecimentos claros e robustos para a condução das ações do enfermeiro na prática clínica.

RESUMEN Objetivo construir una teoría de rango medio para el desarrollo de la propuesta diagnóstica del riesgo de volumen excesivo de líquidos en pacientes en hemodiálisis. Método se trata de un estudio metodológico, desarrollado para la validez teórico-causal de un diagnóstico de enfermería. El estudio se realizó en cuatro etapas: selección de estudios, identificación de los principales conceptos de la teoría, construcción del pictograma y elaboración de proposiciones. Estos pasos se pusieron en práctica a través de una revisión integradora de la literatura, con una muestra de 82 artículos seleccionados de las bases de datos Web of Science, PubMed, CINAHL, Scopus y Science Direct. Resultados los datos extraídos de los artículos permitieron identificar cinco términos esenciales para definir el riesgo de exceso de volumen de líquido. Además, se identificaron 31 factores etiológicos de riesgo de exceso de volumen de líquidos, además de un pictograma y 12 proposiciones. Conclusión e implicaciones para la práctica la construcción de una teoría de rango medio centrada en el riesgo de volumen excesivo de líquido en pacientes en hemodiálisis afina la terminología y amplía la comprensión de los fenómenos de enfermería. Así, los datos de esta investigación proporcionarán un conocimiento claro y robusto para la conducción de las acciones del enfermero en la práctica clínica.

ABSTRACT Objective to construct a middle range theory for developing the excessive fluid volume risk diagnostic proposition in patients undergoing hemodialysis. Method this is a methodological study, developed for the theoretical-causal validity of a nursing diagnosis. The study was carried out in four stages: study selection, identification of the main concepts of the theory, pictogram construction and proposition elaboration. These steps were operationalized through an integrative literature review, with a sample of 82 articles selected from the Web of Science, PubMed, CINAHL, Scopus and Science Direct databases. Results the data extracted from the sample articles enabled identifying five essential terms to define excessive fluid volume risk. Furthermore, 31 etiological factors of excessive fluid volume risk were identified, in addition to a pictogram and 12 propositions. Conclusion and implications for practice the construction of a middle-range theory focused on excessive fluid volume risk in patients undergoing hemodialysis refines terminology and expands the understanding of nursing phenomena. Thus, the data from this research will provide clear and robust knowledge for the conduct of nurses' actions in clinical practice.

Research progress on biomarkers for endometriosis based on lipidomics / 浙江大学学报·医学版

The pathogenesis of endometriosis is not well understood at the moment, and the lack of effective biomarkers often leads to delayed diagnosis of the disease. Lipidomics provides a new approach for the diagnosis and prediction of endometriosis. Sphingomyelin, phosphatidylcholine and phosphatidylserine in peripheral blood, endometrial fluid, peritoneal fluid and follicular fluid have good diagnostic value for endometriosis and disease classification; the lipid metabolites in the eutopic endometrium tissue are expected to be biomarkers of early endometriosis; and the lipid metabolites in peripheral blood are also of great value for predicting endometriosis-related infertility. The development of lipidomics technique will further advance the progress on the pathogenesis, prediction, diagnosis and treatment of endometriosis.

Performance Evaluation of Body Fluid Cellular Analysis Using the Beckman Coulter UniCel DxH 800, Sysmex XN-350, and UF-5000 Automated Cellular Analyzers

BACKGROUND: Automated cellular analyzers are expected to improve the analytical performance in body fluid (BF) analysis. We evaluated the analytical performance of three automated cellular analyzers and established optimum reflex analysis guidelines. METHODS: A total of 542 BF samples (88 cerebrospinal fluid [CSF] samples and 454 non-CSF samples) were examined using manual counting and three automated cellular analyzers: UniCel DxH 800 (Beckman Coulter), XN-350 (Sysmex), and UF-5000 (Sysmex). Additionally, 2,779 BF analysis results were retrospectively reviewed. For malignant cell analysis, the receiver operating characteristic (ROC) curve was used, and the detection of high fluorescence-BF cells (HF-BFs) using the XN-350 analyzer was compared with cytology results. RESULTS: All three analyzers showed good agreement for total nucleated cell (TNC) and red blood cell (RBC) counts, except for the RBC count in CSF samples using the UniCel DxH 800. However, variable degrees of differences were observed during differential cell counting. For malignant cell analysis, the area under the curve was 0.63 for the XN-350 analyzer and 0.76 for manual counting. We established our own reflex analysis guidelines as follows: HF-BFs 83.4/100 WBCs or eosinophils >3.8% are the criteria for mandatory double check confirmation with 1,000× magnification examination. CONCLUSIONS: The three automated analyzers showed good analytical performances. Application of reflex analysis guidelines is recommended for eosinophils and HF-BFs, and manual confirmation is warranted.

Comparison of 16S Ribosomal RNA Targeted Sequencing and Culture for Bacterial Identification in Normally Sterile Body Fluid Samples: Report of a 10-Year Clinical Laboratory Review

As 16S ribosomal RNA (rRNA)-targeted sequencing can detect DNA from non-viable bacteria, it can be used to identify pathogens from clinical samples even in patients pretreated with antibiotics. We compared the results of 16S rRNA-targeted sequencing and culture for identifying bacterial species in normally sterile body fluid (NSBF): cerebrospinal, pericardial, peritoneal and pleural fluids. Over a 10-year period, a total of 312 NSBF samples were evaluated simultaneously using 16S rRNA-targeted sequencing and culture. Results were concordant in 287/312 (92.0%) samples, including 277 (88.8%) negative and 10 (3.2%) positive samples. Of the 16 sequencing-positive, culture-negative samples, eight showed clinically relevant isolates that included Fusobacterium nucleatum subsp. nucleatum, Streptococcus pneumoniae, and Staphylococcus spp. All these samples were obtained from the patients pretreated with antibiotics. The diagnostic yield of 16S rRNA-targeted sequencing combined with culture was 11.2%, while that of culture alone was 6.1%. 16S rRNA-targeted sequencing in conjunction with culture could be useful for identifying bacteria in NSBF samples, especially when patients have been pretreated with antibiotics and when anaerobic infection is suspected.

Mesenchymal stem cell therapy for acute respiratory distress syndrome: from basic to clinics

The 2019 novel coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has occurred in China and around the world. SARS-CoV-2-infected patients with severe pneumonia rapidly develop acute respiratory distress syndrome (ARDS) and die of multiple organ failure. Despite advances in supportive care approaches, ARDS is still associated with high mortality and morbidity. Mesenchymal stem cell (MSC)-based therapy may be an potential alternative strategy for treating ARDS by targeting the various pathophysiological events of ARDS. By releasing a variety of paracrine factors and extracellular vesicles, MSC can exert anti-inflammatory, anti-apoptotic, anti-microbial, and pro-angiogenic effects, promote bacterial and alveolar fluid clearance, disrupt the pulmonary endothelial and epithelial cell damage, eventually avoiding the lung and distal organ injuries to rescue patients with ARDS. An increasing number of experimental animal studies and early clinical studies verify the safety and efficacy of MSC therapy in ARDS. Since low cell engraftment and survival in lung limit MSC therapeutic potentials, several strategies have been developed to enhance their engraftment in the lung and their intrinsic, therapeutic properties. Here, we provide a comprehensive review of the mechanisms and optimization of MSC therapy in ARDS and highlighted the potentials and possible barriers of MSC therapy for COVID-19 patients with ARDS.

Mesenchymal stem cell therapy for acute respiratory distress syndrome: from basic to clinics

The 2019 novel coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has occurred in China and around the world. SARS-CoV-2-infected patients with severe pneumonia rapidly develop acute respiratory distress syndrome (ARDS) and die of multiple organ failure. Despite advances in supportive care approaches, ARDS is still associated with high mortality and morbidity. Mesenchymal stem cell (MSC)-based therapy may be an potential alternative strategy for treating ARDS by targeting the various pathophysiological events of ARDS. By releasing a variety of paracrine factors and extracellular vesicles, MSC can exert anti-inflammatory, anti-apoptotic, anti-microbial, and pro-angiogenic effects, promote bacterial and alveolar fluid clearance, disrupt the pulmonary endothelial and epithelial cell damage, eventually avoiding the lung and distal organ injuries to rescue patients with ARDS. An increasing number of experimental animal studies and early clinical studies verify the safety and efficacy of MSC therapy in ARDS. Since low cell engraftment and survival in lung limit MSC therapeutic potentials, several strategies have been developed to enhance their engraftment in the lung and their intrinsic, therapeutic properties. Here, we provide a comprehensive review of the mechanisms and optimization of MSC therapy in ARDS and highlighted the potentials and possible barriers of MSC therapy for COVID-19 patients with ARDS.

Mesenchymal stem cell therapy for acute respiratory distress syndrome: from basic to clinics

The 2019 novel coronavirus disease (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has occurred in China and around the world. SARS-CoV-2-infected patients with severe pneumonia rapidly develop acute respiratory distress syndrome (ARDS) and die of multiple organ failure. Despite advances in supportive care approaches, ARDS is still associated with high mortality and morbidity. Mesenchymal stem cell (MSC)-based therapy may be an potential alternative strategy for treating ARDS by targeting the various pathophysiological events of ARDS. By releasing a variety of paracrine factors and extracellular vesicles, MSC can exert anti-inflammatory, anti-apoptotic, anti-microbial, and pro-angiogenic effects, promote bacterial and alveolar fluid clearance, disrupt the pulmonary endothelial and epithelial cell damage, eventually avoiding the lung and distal organ injuries to rescue patients with ARDS. An increasing number of experimental animal studies and early clinical studies verify the safety and efficacy of MSC therapy in ARDS. Since low cell engraftment and survival in lung limit MSC therapeutic potentials, several strategies have been developed to enhance their engraftment in the lung and their intrinsic, therapeutic properties. Here, we provide a comprehensive review of the mechanisms and optimization of MSC therapy in ARDS and highlighted the potentials and possible barriers of MSC therapy for COVID-19 patients with ARDS.

Identification of Peripheral Blood and Menstrual Blood Based on the Expression Level of MicroRNAs and Discriminant Analysis / 法医学杂志

Objective To construct a discriminant analysis model based on the differential expression of multiple microRNAs （miRNAs） in two kinds of blood samples （peripheral blood and menstrual blood） and three non-blood samples （saliva, semen and vaginal secretion）, to form an identification solution for peripheral blood and menstrual blood. Methods Six kinds of miRNA （miR-451a, miR-144-3p, miR-144-5p, miR-214-3p, miR-203-3p and miR-205-5p） were selected from literature, the samples of five kinds of body fluids commonly seen in forensic practice （peripheral blood, menstrual blood, saliva, semen, vaginal secretion） were collected, then the samples were divided into training set and testing set and detected by SYBR Green real-time qPCR. A discriminant analysis model was set up based on the expression data of training set and the expression data of testing set was used to examine the accuracy of the model. Results A discriminant analysis statistical model that could distinguish blood samples from non-blood samples and distinguish peripheral blood samples from menstrual blood samples at the same time was successfully constructed. The identification accuracy of the model was over 99%. Conclusion This study provides a scientific and accurate identification strategy for forensic fluid identification of peripheral blood and menstrual blood samples and could be used in forensic practice.

Evaluation of the cervicovaginal environment in asymptomatic Human T-cell lymphotropic virus type 1 infected women

ABSTRACT Introduction: Human T-cell lymphotropic virus type 1 (HTLV-1) is sexually transmitted and causes persistent infection. This virus induces activation of the immune system and production of inflammatory cytokines. This study aimed to assess the cytokine profile and cytopathological findings in the cervicovaginal fluid of asymptomatic HTLV-1-infected women. Methods: HTLV-1-infected and uninfected women were selected at the Centro de Atendimento ao Portador de HTLV in Salvador-Brazil. None of the included HTLV-1-infected women reported any HTLV-1-associated diseases. All volunteers underwent gynecological examination to collect cervicovaginal fluid. Cytokine quantification was performed using the Cytometric Bead Array (CBA) Human Th1/Th2/Th17 kit. Light microscopy was used to evaluate cervicovaginal cytopathology. In addition, proviral load in cervicovaginal fluid and peripheral blood was measured by real-time quantitative polymerase chain reaction. Results: 112 women (63 HTLV-1-infected and 49 uninfected) were evaluated. No differences were found with respect to cytopathological cervicovaginal findings between the groups. IL-2, TNF, IL-4, IL-10, and IL-17 levels were significantly higher in cervicovaginal fluid of the HTLV-1-infected women than in uninfected women (p < 0.05). Conversely, IFN-γ was found to be lower in the HTLV-1-infected women (p < 0.001) compared to uninfected individuals. Cervicovaginal proviral load was detectable in 53% of the HTLV-1-infected women and was found to be consistently lower than the proviral load in peripheral blood. Conclusions: HTLV-1 infection induces immune activation in cervicovaginal environment, characterized by elevated concentrations of Th1, Th2, and IL17 in the cervicovaginal fluid.

Determinants of occupational exposure to blood and body fluids, healthcare workers' risk perceptions and standard precautionary practices: a hospital-based study in Addis Ababa, Ethiopia

Abstract Background: The risk of occupational exposure to blood-borne infections is on the rise in hospital settings. The situation is worse in developing countries for a variety of reasons, such as poor working condition, excessive injection use, and poor adherence towards universal precautions. This study was undertaken to assess the determining factors of occupational exposures to blood-borne infections, as well as to describe healthcare workers' risk perceptions and standard precautionary practices in selected hospitals in Addis Ababa, Ethiopia. Methods: A cross-sectional study was conducted from December 2016 to January 2017. A total of 323 healthcare workers from four public hospitals were selected for the study using a simple random-sampling technique. Structured questions administered by an interviewer were used to collect data. Multivariable binary logistic regression was used to identify the determining factors. Results: Healthcare workers' lifetime and one-year prevalence of needlestick injuries were 39.0% (95% CI: 33.6-44.8) and 19.9% (95% CI: 15.2-24.5), respectively. The lifetime and one-year prevalence of blood and body fluid exposures were 42.6% (95% CI: 36.8-48.4) and 29.2% (95% CI: 23.8-34.7), respectively. Almost three out of five healthcare workers, 62.8% (95% CI: 57.0-68.9) had adequate risk perception, and 41.2% (95% CI: 35.4-46.9) adopted good standards of precautionary practice. Service year (AOR: 2.40; 95% CI:1.00-5.77) and having poor standards of precautionary practice (AOR: 2.30; 95% CI: 1.18-4.46) were the determinants of needlestick injuries. Conclusions: The high prevalence of occupational exposure and healthcare workers' sub-optimal practice of taking standard precautions seemed to be common. Long-term and in-service, focused, short-term training were found to be helpful in increasing awareness of the risks and reducing exposure to them