Determinants and Magnitude of Neonatal Sepsis at Hiwot Fana Comprehensive Specialized University Hospital, in Eastern Ethiopia: A Cross-Sectional Study.

Background: Neonatal sepsis is a serious blood bacterial infection in neonates at the age of equal to or less than 28 days of life, and it's still the major significant cause of death and long-term morbidity in developing countries. Objective: This study aimed to assess the prevalence and related factors with neonatal sepsis among newborns admitted to the neonatal intensive care unit at Hiwot Fana Comprehensive Specialized University Hospital, Harar, Ethiopia. Methods: An institutional-based retrospective cross-sectional study design was conducted among 386 neonates admitted to Neonatal Intensive Care Unit from September 2017 to August 2019. A systematic random sampling method was used. Data were analyzed using SPSS V.26. Descriptive summary statistics were done. Bivariate regression and multivariate analysis were computed. Variables with P-value <.05 were declared as having a statistically significant association. Result: The prevalence of neonatal sepsis was 53.1%. Among the total neonates who had sepsis, 67.8% had early neonatal sepsis. Among neonatal factors, preterm neonates (AOR: 8.1, 95%CI: 2.1, 31.2), birth asphyxia (AOR: 4.7, 95%CI: 1.6, 13.6); and among maternal factors, urban residence (AOR: 0.26, 95%CI: 0.1, 0.5), antenatal care attendance (AOR: 0.32, 95%CI: 0.2, 0.6), spontaneous vaginal delivery (AOR: 0.047, 95%CI: 0.01, 0.2), and maternal antibiotic use (AOR: 0.39; 95%CI: 0.2, 0.8) were found to have significant association with neonatal sepsis. Conclusion: Overall, the magnitude of neonatal sepsis was high. Provision of neonatal and obstetrics care as per standard during prenatal, intranatal, and postnatal periods is needed. Training of health professionals on infection prevention and safe delivery practice should be provided.

Surface Modification Strategies for Chrysin-Loaded Iron Oxide Nanoparticles to Boost Their Anti-Tumor Efficacy in Human Colon Carcinoma Cells.

Enhancing nanoparticles' anti-cancer capabilities as drug carriers requires the careful adjustment of formulation parameters, including loading efficiency, drug/carrier ratio, and synthesis method. Small adjustments to these parameters can significantly influence the drug-loading efficiency of nanoparticles. Our study explored how chitosan and polyethylene glycol (PEG) coatings affect the structural properties, drug-loading efficiency, and anti-cancer efficacy of Fe3O4 nanoparticles (NPs). The loading efficiency of the NPs was determined using FTIR spectrometry and XRD. The quantity of chrysin incorporated into the coated NPs was examined using UV-Vis spectrometry. The effect of the NPs on cell viability and apoptosis was determined by employing the HCT 116 human colon carcinoma cell line. We showed that a two-fold increase in drug concentration did not impact the loading efficiency of Fe3O4 NPs coated with PEG. However, there was a 33 Å difference in the crystallite sizes obtained from chitosan-coated Fe3O4 NPs and drug concentrations of 1:0.5 and 1:2, resulting in decreased system stability. In conclusion, PEG coating exhibited a higher loading efficiency of Fe3O4 NPs compared to chitosan, resulting in enhanced anti-tumor effects. Furthermore, variations in the loaded amount of chrysin did not impact the crystallinity of PEG-coated NPs, emphasizing the stability and regularity of the system.

A Path of Novelty from Nanoparticles to Nanobots: Theragnostic Approach for Targeting Cancer Therapy.

Pharmaceutical development of cancer therapeutics is a dynamic area of research. Even after decades of intensive work, cancer continues to be a dreadful disease with an ever-increasing global incidence. The progress of nanotechnology in cancer research has overcome inherent limitations in conventional cancer chemotherapy and fulfilled the need for target-specific drug carriers. Nanotechnology uses the altered patho-physiological microenvironment of malignant cells and offers various advantages like improved solubility, reduced toxicity, prolonged drug circulation with controlled release, circumventing multidrug resistance, and enhanced biodistribution. Early cancer detection has a crucial role in selecting the best drug regime, thus, diagnosis and therapeutics go hand in hand. Furthermore, nanobots are an amazing possibility and promising innovation with numerous significant applications, particularly in fighting cancer and cleaning out blood vessels. Nanobots are tiny robots, ranging in size from 1 to 100 nm. Moreover, the nanobots would work similarly to white blood cells, watching the bloodstream and searching for indications of distress. This review articulates the evolution of various organic and inorganic nanoparticles and nanobots used as therapeutics, along with their pros and cons. It also highlights the shift in diagnostics from conventional methods to more advanced techniques. This rapidly growing domain is providing more space for engineering desired nanoparticles that can show miraculous results in therapeutic and diagnostic trials.

Prevalence and Associated Factors of Anemia Among Hospital Admitted Patients in Eastern Ethiopia.

Background: Anemia is one of the most common comorbidities frequently seen in admitted patients. However, there is a scarcity of evidence regarding anemia among hospital admitted patients in Ethiopia, particularly in the Harari Region. Therefore, this study aimed to assess the prevalence and associated factors of anemia among hospital admitted patients in Eastern Ethiopia. Methods: A hospital-based cross-sectional study was conducted from October 25 to December 30, 2022. Four milliliters of venous blood were collected and complete blood count was done using the DxH 800 (Beckman Coulter, Inc, Miami, FL) hematology analyzer. The data were entered in Epi-data version 4 and exported to SPSS version 26 for statistical analysis. Bivariable and multivariable logistic regression models were fitted. The level of significance was declared at a p-value of < 0.05. Results: Of the 381 hospital admitted patients, 64.8% (95% CI = 60.01, 69.65) of the participants were anemic. Admitted patients who drank standard alcohol daily (AOR = 3.78, 95% CI = 1.71, 8.30), underweight (AOR = 9.39, 95% CI = 2.90, 30.46), and undernourished patients (AOR = 2.59, 95% CI = 1.15, 5.84), patients admitted with chronic kidney disease (AOR = 11.16, 95% CI = 4.06, 30.64), chronic liver disease (AOR = 3.20, 95% CI = 1.21, 8.47), deep vein thrombosis (AOR = 6.22, 95% CI = 1.98, 19.52), infectious disease (AOR = 9.71, 95% CI = 2.77, 34.02), and chronic non-communicable disease (AOR = 7.01, 95% CI = 1.90, 25.99) were all significantly associated with anemia. Conclusion: Anemia was common among hospital admitted patients and should prompt the focus on admission diagnoses that are likely to play leading roles in etiology. This information indicates a need for routine screening of anemia for all admitted patients to improve their health.

Levels and predictors of knowledge of epilepsy among patients attending the epilepsy clinic of a neuro-psychiatric facility in North-Eastern Nigeria.

Introduction: significant numbers of patients with epilepsy have poor knowledge of their disease. Patients' knowledge of disease is related to their success in coping with the disease and adherence to medication; which is one of the key factors that determined the success of pharmacotherapy in patient with epilepsy. In this study, we evaluate the level of knowledge of epilepsy among patient with Epilepsy in a tertiary mental health care facility. Methods: using a cross-sectional design, 410 patients with epilepsy attending general outpatient clinic of Federal Neuropsychiatric Hospital, Maiduguri in Northeastern Nigeria were sampled randomly into the study after fulfilling the inclusion and exclusion criteria. Socio-demographic, clinical and epilepsy knowledge questionnaires were used for data collection. Data were analyzed using the Statistical Package for Social Sciences (SPSS) version 18. Results: 263 (64.1%) had poor knowledge of epilepsy and 290 (70%) had less frequent seizures (having fewer than four seizure episodes in the last three months). Independent predictors of knowledge of Epilepsy were intermediate skilled employment (O.R = 2.32, P = 0.022, 95% C I = 1.13 - 4.76); semi-skilled employment (O. R = 1/85, p = 0.001, 95% C I = 1.10 - 3.12); seizure frequency (O R = 1.72, p = 0.031, 95% C I = 1.31 - 3.24). Conclusion: the level of knowledge of epilepsy among people with epilepsy was low with more than 64.1% percent of the participants had poor knowledge of epilepsy. Occupational status and seizure frequencies were independent predictors of knowledge of epilepsy. We therefore recommend psycho-educational programs be incorporated in the routine clinical care of the patients and for clinicians to pay more attention to providing information and education needs of patients.

Determinants of WHO recommended COVID-19 prevention measures among pregnant women attending antenatal care during the third wave of COVID-19 in eastern Ethiopia, 2021.

BACKGROUND: The novel coronavirus disease has emerged as the most pressing global health issue. In women with COVID-19 disease, pregnancy confers a substantial additional risk of morbidity and mortality. OBJECTIVE: This study aimed to assess WHO-recommended COVID-19 prevention practices and determinant factors among pregnant women attending antenatal care during the third wave of COVID-19 in eastern Ethiopia. METHODS: An Institutional-based cross-sectional study was conducted among 422 pregnant women attending antenatal care in Harar, from October 10 to November 10, 2021. The sample size was proportionally allocated to all healthcare facilities, then the study participants were selected using systematic random sampling. Descriptive summary statistics were done. Logistic regression analyses were computed to identify associations between dependent and independent variables. Variables with a p-value < 0.05 were declared statistically significant. RESULT: Out of 422 pregnant women, 61.6% of them had good WHO Recommended COVID-19 Prevention Practices. Those with age 25-34 years (AOR: 9.7, 95%CI: 4.8, 19.3), age 35-44 years (AOR:4.8, 95%CI: 2.6, 9.03), monthly income > 10,000 ETB (AOR: 9.4, 95%CI: 2.1, 42.1), being a student (AOR: 10, 95%CI: 2.3, 47.1), having a good level of knowledge (AOR: 2.3, 95%CI:1.4, 3.8), and having ≥10 family members (AOR: 0.24, 95%CI: 0.06, 0.9) were found to have a significant association with WHO recommended prevention practice among pregnant women. CONCLUSION: Overall, the WHO-recommended COVID-19 prevention practice among pregnant women attending antenatal care was good, but it needs improvement. In order to improve prevention practices among pregnant women, Harari Regional Health Bureau and other stakeholders should provide repeated, targeted, and tailored information to pregnant women and the community at large through different media.

Fluoride occurrence in environment, regulations, and remediation methods for soil: A comprehensive review.

Fluoride, a naturally occurring chemical element, is largely insoluble in soils. More than 90% of the fluoride in soil is bound to soil particles and is unable to be dissolved. As part of the soil, fluoride is predominantly located in the colloid or clay fraction of the soil, and the movement of fluoride is strongly affected by the sorption capacity of the soil, which is affected by pH, the type of soil sorbent present, and the salinity. The Canadian Council of Ministers of the Environment soil quality guideline for fluoride in soils under a residential/parkland land use scenario is 400 mg/kg. In this review, we focus on fluoride contamination in soil and subsurface environments, and the various sources of fluorides are discussed in detail. The average fluoride concentration in soil in different countries and their regulations for soil and water are comprehensively reviewed. In this article, the latest advances in defluoridation methods are highlighted and the importance of further research addressing efficient and cost-effective methods to remediate fluoride contamination in soil is critically discussed. Methods used to mitigate fluoride risks by removing fluoride from the soil are presented. We strongly recommend that regulators and soil chemists in all countries explore opportunities to improve defluoridation methods and consider adopting more stringent regulations for fluoride in soil depending on geologic conditions.

Level and determinants of knowledge, attitude, and practice of risky sexual behavior among adolescents in Harar, Ethiopia.

Background: Adolescence is a transition period of advancement from a state of immature sexual characteristics to sexual and reproductive maturity; an improvement in the mental form progressing to the mental maturity of a grown-up adult; and a period of transition from total socioeconomic dependence to relative independence. An adolescent is defined as a person aged between 10 and 19 years. This study assessed the level and determinant factors of knowledge, attitude, and practice of risky sexual behavior among secondary school adolescents in Harar, Eastern Ethiopia, 2022. Methods: A school-based cross-sectional study design was employed. From the total population of adolescents, 387 respondents were sampled. A simple random sampling method was used to select study participants. The data was collected by using a self-administered questionnaire and analyzed using SPSS version 26. Result: Among the participants, 47.3% had good knowledge of risky sexual behavior. 41.9% had a positive attitude toward risky sexual behavior. 36.1% of students had started sexual activity before they reached 18 years old. Out of 9.3% of respondents who have had sexual intercourse, almost 50% of them had multiple partners. Students who live in urban areas were three times (adjusted odds ratio: 3.3, 95% CI: 1.6, 6.6) more likely to have good knowledge about risky sex than their counterparts in rural settings. Conclusion: There is a significant number of risky sexual behaviors, such as having a different sexual partner and having unprotected sex with a non-regular partner. Being female, in urban residence, not having pocket money, and attending parties have significant associations with having good knowledge about risky sex. Harari Regional Educational and Health Bureau should provide repeated tailored information that can specifically address the attitude of the adolescents toward risky sexual behavior using different media, teachers, and school clubs in respect of sexual and reproductive health. The existing adolescent reproductive health program should be strengthened and evaluated to improve the sexual behavior of adolescents.

SPIONs Conjugate Supported Anticancer Drug Doxorubicin's Delivery: Current Status, Challenges, and Prospects.

Considerable efforts have been directed towards development of nano-structured carriers to overcome the limitations of anticancer drug, doxorubicin's, delivery to various cancer sites. The drug's severe toxicity to cardio and hepatic systems, low therapeutic outcomes, inappropriate dose-demands, metastatic and general resistance, together with non-selectivity of the drug have led to the development of superparamagnetic iron oxide nanoparticles (SPIONs)-based drug delivery modules. Nano-scale polymeric co-encapsulation of the drug, doxorubicin, with SPIONs, the SPIONs surface end-groups' cappings with small molecular entities, as well as structural modifications of the SPIONs' surface-located functional end-groups, to attach the doxorubicin, have been achieved through chemical bonding by conjugation and cross-linking of natural and synthetic polymers, attachments of SPIONs made directly to the non-polymeric entities, and attachments made through mediation of molecular-spacer as well as non-spacer mediated attachments of several types of chemical entities, together with the physico-chemical bondings of the moieties, e.g., peptides, proteins, antibodies, antigens, aptamers, glycoproteins, and enzymes, etc. to the SPIONs which are capable of targeting multiple kinds of cancerous sites, have provided stable and functional SPIONs-based nano-carriers suitable for the systemic, and in vitro deliveries, together with being suitable for other biomedical/biotechnical applications. Together with the SPIONs inherent properties, and ability to respond to magnetic resonance, fluorescence-directed, dual-module, and molecular-level tumor imaging; as well as multi-modular cancer cell targeting; magnetic-field-inducible drug-elution capacity, and the SPIONs' magnetometry-led feasibility to reach cancer action sites have made sensing, imaging, and drug and other payloads deliveries to cancerous sites for cancer treatment a viable option. Innovations in the preparation of SPIONs-based delivery modules, as biocompatible carriers; development of delivery route modalities; approaches to enhancing their drug delivery-cum-bioavailability have explicitly established the SPIONs' versatility for oncological theranostics and imaging. The current review outlines the development of various SPIONs-based nano-carriers for targeted doxorubicin delivery to different cancer sites through multiple methods, modalities, and materials, wherein high-potential nano-structured platforms have been conceptualized, developed, and tested for, both, in vivo and in vitro conditions. The current state of the knowledge in this arena have provided definite dose-control, site-specificity, stability, transport feasibility, and effective onsite drug de-loading, however, with certain limitations, and these shortcomings have opened the field for further advancements by identifying the bottlenecks, suggestive and plausible remediation, as well as more clear directions for future development.

COVID-19 vaccine side effect: age and gender disparity in adverse effects following the first dose of AstraZeneca COVID-19 vaccine among the vaccinated population in Eastern Ethiopia: a community-based study.

Objective: The pandemic of coronavirus disease 2019 (COVID-19) is a major threat to community health, and vaccinations are a safe and effective way to reduce disease loads around the world. This study aimed to assess the age and gender disparity in adverse effects following the first dose of the AstraZeneca COVID-19 vaccine among the vaccinated population in Eastern Ethiopia. Methods: A community-based cross-sectional study design was conducted among 832 randomly selected individuals from December 1st to 20th, 2021, in eastern Ethiopia. Data were collected by face-to-face interviews using a pretested structured questionnaire. Data were analyzed using the SPSS V26. Descriptive summary statistics were done. A chi-square test statistic was computed to assess the difference in adverse effects between age groups and both genders. Result: Out of 832 study participants who had taken the first dose of AstraZeneca vaccine, 96.3% of them felt at least one adverse effect. The magnitude of adverse reactions was higher among male participants. The reported adverse reactions were significantly higher in the age group of 50-60 years with comorbidity than those of <50 and >60 years of age. Conclusion: Overall, there is a significant age and gender difference in adverse effects following the first dose of the AstraZeneca COVID-19 vaccine. In addition, adverse reactions were higher among people with comorbidity in the age group of 50-60 years. The Harari Regional Health Bureau should provide training for frontline healthcare workers on early recognition and response to adverse effects of the COVID-19 vaccine. In addition, information and education should be provided to the community as a whole regarding recognition and the appropriate measures to be taken.

Covid-19 Vaccine Acceptance and Determinant Factors among General Public in East Africa: A Systematic Review and Meta-Analysis.

Background: Vaccines are an effective and ideal solution that can reduce the burden of disease worldwide. Although vaccines are the most effective way to prevent infectious diseases. Anti-vaccine conspiracy theories impair vaccination acceptance intentions. Several studies were conducted in East Africa. However, these studies had reported inconsistent findings. Therefore, this systematic review aimed to pool the prevalence of COVID-19 vaccine acceptance and identify its determinants. Methods: PubMed, Google Scholar, and GLOBAL HEALTH databases were used to retrieve previously published studies. All papers published in the English language up to February 28, 2022 were included. The result was written and reported according to the PRISMA updated guideline. A random-effect model was used to estimate the pooled prevalence and effect sizes. Heterogeneity was assessed using I2 test statistics. Publication bias was assessed using funnel plot and egger's test statistics. Statistical tests result at P-value<0.05 were declared as having significance.Result: A total of 25 Cross-sectional studies with a total sample size of 33,044 were included in this study. The pooled prevalence of Covid-19 vaccine acceptance was 60.2%, (95%CI: 52.8- 67.3). Egger's test statistics (P = 0.003) showed there is a significant publication bias. Attending above secondary school (AOR: 2.1, 95%CI: 1.37, 2.96), having good knowledge about the vaccine (AOR: 2.1, 95%CI: 1.6, 2.8), having a positive attitude towards vaccine (AOR: 3.8, 95%CI: 2.3, 6.2), history of COVID-19 infection (AOR: 2.7, 95%CI: 1.6, 4.7) and being male (AOR: 1.8, 95%CI: 1.2, 2.7) were found to have a significant association with COVID-19 vaccine acceptance. Conclusion: The COVID-19 vaccination acceptance rate was good, but it could be improved. The findings could help governments to figure out the best way to carry out COVID-19 mass vaccination campaigns. There is a lack of data in most countries. Therefore, we suggest more studies be conducted in the future.

Measles outbreak response immunization during the COVID-19 pandemic: lessons from Borno State, Nigeria.

Introduction: the COVID-19 outbreak was declared a public health emergency of international concern by the WHO on the 30th January 2020. The occurrence of measles outbreaks in the context of COVID-19, both highly infectious respiratory illnesses, impacts additional challenges to the health system in a state with an ongoing humanitarian crisis. This article documents the implementation of an outbreak response immunization (ORI) during the COVID-19 pandemic and the implementation of global guidelines for mass vaccination. Methods: a retrospective review of the response to measles outbreak implemented in Borno state across six local government areas (LGAs) in 2019 was conducted. This review assessed the utilization of the World Health Organization (WHO) decision making framework, measles and COVID-19 epidemiological reports and the measle's vaccination response data. Results: an outbreak response immunization was implemented in six LGAs in Borno State, with a validated post campaign coverage of 96.3% (95% CI: 93.0 - 98.1). In total, 181,634 children aged 9 months-9 years were vaccinated with 27,961 (15.4%) receiving the measles vaccine for the first time. Prior to the interventions, 20 COVID-19 cases were reported in the six LGAs while only seven suspected cases were reported with only two cases confirmed in one of the six LGAs four weeks after the ORI. Conclusion: the WHO decision-making framework for implementing mass vaccinations in the context of the COVID-19 Pandemic was utilized for the outbreak response immunization in Borno State, Nigeria with 181,634 children aged 9 Months-9 years vaccinated with the measles vaccine. The use of the WHO decision-making framework to assess risk benefits of initiating mass vaccination campaigns remains a very important practical tool. These types of responses in Nigeria and other low and middle income countries (LMICs), with hitherto suboptimal immunization coverage and weak health systems and other settings, affected by humanitarian emergencies is essential in the achievement of the regional measle's elimination targets.

Determinants of COVID-19 vaccine uptake and barriers to being vaccinated among first-round eligibles for COVID-19 vaccination in Eastern Ethiopia: A community based cross-sectional study.

OBJECTIVE: Coronavirus disease is a deadly virus that continues to afflict many countries worldwide. Ethiopia has planned to give vaccines to 20% of the population by March 2022. This study aimed to assess determinants of vaccine uptake and barriers to being vaccinated among first-round eligibles for coronavirus disease vaccination in Harar, eastern Ethiopia. METHODS: A community-based cross-sectional study design was conducted among 820 randomly selected coronavirus disease first-round eligible groups in Harar from August 20 to September 15, 2021. Descriptive summary statistics were done. Logistic regression analyses were computed to identify associations between dependent and independent variables. Variables with a p value of <0.05 were declared statistically significant. RESULT: Out of 820, only 39.4% of participants took the coronavirus disease vaccine. The main barriers to being vaccinated were, belief vaccine has no use (24%), and belief vaccine causes blood clots (17.9%). Being a merchant (adjusted odds ratio: 7.9, 95% confidence interval: 2.6, 24), people who had no schooling (adjusted odds ratio: 2.5, 95% confidence interval: 1.3, 4.9), having attitude below the mean score (adjusted odds ratio: 2.1, 95% confidence interval: 1.4, 2.8), having coronavirus disease prevention practice above the mean score (adjusted odds ratio: 2.1, 95% confidence interval: 1.4, 2.8), and family size < 5 members (adjusted odds ratio: 0.64, 95% confidence interval: 0.4, 0.9) were found to be significantly associated with coronavirus disease vaccination. CONCLUSION: Overall, coronavirus disease-19's first-round vaccination status was low. The number of people vaccinated was higher among 50-60 age groups than those who are >60 years. Being female, being a person with no schooling, being a merchant, being a farmer, and having low coronavirus disease prevention practice was found to be significantly associated with coronavirus disease vaccination. We recommend that the Federal Ministry of Health, Harari Regional Health Bureau, and other concerned stakeholders should work more diligently to provide continued campaigning on coronavirus disease vaccination and better vaccine awareness creation, as this is the only way out of this epidemic.

Quantitative phase measurements of human cell nuclei using X-ray ptychography.

The human cell nucleus serves as an important organelle holding the genetic blueprint for life. In this work, X-ray ptychography was applied to assess the masses of human cell nuclei using its unique phase shift information. Measurements were carried out at the I13-1 beamline at the Diamond Light Source that has extremely large transverse coherence properties. The ptychographic diffractive imaging approach allowed imaging of large structures that gave quantitative measurements of the phase shift in 2D projections. In this paper a modified ptychography algorithm that improves the quality of the reconstruction for weak scattering samples is presented. The application of this approach to calculate the mass of several human nuclei is also demonstrated.

Ultra-Structural Imaging Provides 3D Organization of 46 Chromosomes of a Human Lymphocyte Prophase Nucleus.

Three dimensional (3D) ultra-structural imaging is an important tool for unraveling the organizational structure of individual chromosomes at various stages of the cell cycle. Performing hitherto uninvestigated ultra-structural analysis of the human genome at prophase, we used serial block-face scanning electron microscopy (SBFSEM) to understand chromosomal architectural organization within 3D nuclear space. Acquired images allowed us to segment, reconstruct, and extract quantitative 3D structural information about the prophase nucleus and the preserved, intact individual chromosomes within it. Our data demonstrate that each chromosome can be identified with its homolog and classified into respective cytogenetic groups. Thereby, we present the first 3D karyotype built from the compact axial structure seen on the core of all prophase chromosomes. The chromosomes display parallel-aligned sister chromatids with familiar chromosome morphologies with no crossovers. Furthermore, the spatial positions of all 46 chromosomes revealed a pattern showing a gene density-based correlation and a neighborhood map of individual chromosomes based on their relative spatial positioning. A comprehensive picture of 3D chromosomal organization at the nanometer level in a single human lymphocyte cell is presented.

Combining Multicolor FISH with Fluorescence Lifetime Imaging for Chromosomal Identification and Chromosomal Sub Structure Investigation.

Understanding the structure of chromatin in chromosomes during normal and diseased state of cells is still one of the key challenges in structural biology. Using DAPI staining alone together with Fluorescence lifetime imaging (FLIM), the environment of chromatin in chromosomes can be explored. Fluorescence lifetime can be used to probe the environment of a fluorophore such as energy transfer, pH and viscosity. Multicolor FISH (M-FISH) is a technique that allows individual chromosome identification, classification as well as assessment of the entire genome. Here we describe a combined approach using DAPI as a DNA environment sensor together with FLIM and M-FISH to understand the nanometer structure of all 46 chromosomes in the nucleus covering the entire human genome at the single cell level. Upon DAPI binding to DNA minor groove followed by fluorescence lifetime measurement and imaging by multiphoton excitation, structural differences in the chromosomes can be studied and observed. This manuscript provides a blow by blow account of the protocol required to perform M-FISH-FLIM of whole chromosomes.

X-ray Ptychography Imaging of Human Chromosomes After Low-dose Irradiation.

Studies of the structural and functional role of chromosomes in cytogenetics have spanned more than 10 decades. In this work, we take advantage of the coherent X-rays available at the latest synchrotron sources to extract the individual masses of all 46 chromosomes of metaphase human B and T cells using hard X-ray ptychography. We have produced 'X-ray karyotypes' of both heavy metal-stained and unstained spreads to determine the gain or loss of genetic material upon low-level X-ray irradiation doses due to radiation damage. The experiments were performed at the I-13 beamline, Diamond Light Source, Didcot, UK, using the phase-sensitive X-ray ptychography method.

Correction to: Cryo-nanoscale chromosome imaging-future prospects.

A correction to this paper has been published: https://doi.org/10.1007/s12551-020-00767-5 .

Cryo-nanoscale chromosome imaging-future prospects.

The high-order structure of mitotic chromosomes remains to be fully elucidated. How nucleosomes compact at various structural levels into a condensed mitotic chromosome is unclear. Cryogenic preservation and imaging have been applied for over three decades, keeping biological structures close to the native in vivo state. Despite being extensively utilized, this field is still wide open for mitotic chromosome research. In this review, we focus specifically on cryogenic efforts for determining the mitotic nanoscale chromatin structures. We describe vitrification methods, current status, and applications of advanced cryo-microscopy including future tools required for resolving the native architecture of these fascinating structures that hold the instructions to life.