Systematic identification and characterization of genes in the regulation and biogenesis of photosynthetic machinery.

Photosynthesis is central to food production and the Earth's biogeochemistry, yet the molecular basis for its regulation remains poorly understood. Here, using high-throughput genetics in the model eukaryotic alga Chlamydomonas reinhardtii, we identify with high confidence (false discovery rate [FDR] < 0.11) 70 poorly characterized genes required for photosynthesis. We then enable the functional characterization of these genes by providing a resource of proteomes of mutant strains, each lacking one of these genes. The data allow assignment of 34 genes to the biogenesis or regulation of one or more specific photosynthetic complexes. Further analysis uncovers biogenesis/regulatory roles for at least seven proteins, including five photosystem I mRNA maturation factors, the chloroplast translation factor MTF1, and the master regulator PMR1, which regulates chloroplast genes via nuclear-expressed factors. Our work provides a rich resource identifying regulatory and functional genes and placing them into pathways, thereby opening the door to a system-level understanding of photosynthesis.

A chloroplast protein atlas reveals punctate structures and spatial organization of biosynthetic pathways.

Chloroplasts are eukaryotic photosynthetic organelles that drive the global carbon cycle. Despite their importance, our understanding of their protein composition, function, and spatial organization remains limited. Here, we determined the localizations of 1,034 candidate chloroplast proteins using fluorescent protein tagging in the model alga Chlamydomonas reinhardtii. The localizations provide insights into the functions of poorly characterized proteins; identify novel components of nucleoids, plastoglobules, and the pyrenoid; and reveal widespread protein targeting to multiple compartments. We discovered and further characterized cellular organizational features, including eleven chloroplast punctate structures, cytosolic crescent structures, and unexpected spatial distributions of enzymes within the chloroplast. We also used machine learning to predict the localizations of other nuclear-encoded Chlamydomonas proteins. The strains and localization atlas developed here will serve as a resource to accelerate studies of chloroplast architecture and functions.

Patient-Informed Value Elements in Cost-Effectiveness Analyses of Major Depressive Disorder Treatment: A Literature Review and Synthesis.

OBJECTIVES: Prior work identified 6 key value elements (attributes of treatment and desired outcomes) for individuals living with major depressive disorder (MDD) in managing their condition: mode of treatment, time to treatment helpfulness, MDD relief, quality of work, interaction with others, and affordability. The objective of our study was to identify whether previous cost-effectiveness analyses (CEAs) for MDD treatment addressed any of these value elements. A secondary objective was to identify whether any study engaged patients, family members, and caregivers in the model development process. METHODS: We conducted a systematic literature review to identify published model-based CEAs. We compared the elements of the published studies with the MDD patient value elements elicited in prior work to identify gaps and areas for future research. RESULTS: Of 86 published CEAs, we found that 7 included patient out-of-pocket costs, and 32 included measures of productivity, which were both priorities for individuals with MDD. We found that only 2 studies elicited measures from patients for their model, and 2 studies engaged patients in the modeling process. CONCLUSIONS: Published CEA models for MDD treatment do not regularly include value elements that are a priority for this patient population nor do they include patients in their modeling process. Flexible models that can accommodate elements consistent with patient experience are needed, and a multistakeholder engagement approach would help accomplish this.

Impact of a pharmacy-driven culture callback protocol on antimicrobial therapy optimization in the emergency department.

BACKGROUND: Timely assessment of cultures for discharged patients from the emergency department (ED) is crucial for quality patient care and safety outcomes. The purpose of this study was to evaluate the efficacy of implementing a standardized pharmacy-driven culture callback protocol on antimicrobial therapy optimization for patients discharged from the ED with positive urine, blood, or sexually transmitted infection (STI) cultures. OBJECTIVE: To assess the impact of a pharmacy-driven culture callback process on antimicrobial therapy optimization in the ED. METHODS: This study was a single-centered, institutional review board-exempt quality improvement project conducted in the ED of an acute care facility. Patients were included if they were at least 18 years old and were discharged from the ED with positive cultures collected for suspected urinary, sexually transmitted, or bloodstream infections. The primary outcome was the percentage of patients receiving optimal therapy after the culture callback was completed. Secondary outcomes included time from culture results to review by nursing or pharmacy, return visits to the ED and admissions within 30 days due to infection, and total pharmacist time spent reviewing cultures. RESULTS: When assessing 200 cultures, optimal therapy was greater in the postintervention group compared to the preintervention group (49 vs. 33; P = 0.021). Combined optimal and appropriate therapy was greater in the postintervention group (60 vs. 78; P = 0.006). There was no significant difference for other secondary endpoints; however, there was a great amount of time savings for nursing and providers. CONCLUSION: This study demonstrated an increase in optimal therapy for urinary and STIs with a pharmacy-driven culture callback protocol.

Doctors' understanding of consent law.

BACKGROUND: Obtaining informed consent is an important responsibility of all doctors and is a major component of their day-to-day practice. However, little is known regarding practising doctors' understanding of consent in relation to medical law. AIMS: To gain insights into current doctors' understanding of the legal requisites that underpin the consent of patients to medical procedures in Australia. METHODS: A cross-sectional survey of Western Australian medical practitioners was conducted. A 15-question online questionnaire (SurveyMonkey, USA) was developed and distributed to Western Australia medical practitioners via social media, hospital-based Junior doctor society pages and through the email accounts of practitioners registered with MDA National - a large medical defence organisation. Doctors were questioned on their understanding of medicolegal responsibilities, informed consent practice and knowledge of a historically significant Australian medicolegal case (Rogers v Whitaker, 1992). RESULTS: A total of 172 responses was received during the survey period. The respondents came from various levels of seniority and from a variety of subspecialist areas. The survey demonstrated that among the respondents, the understanding of their medicolegal responsibilities around the issues of informed consent was deficient. Only 31% of respondents were aware that it is a court of law that defines the reasonable standard of care in relation to obtaining informed consent. Less than half of the respondents (48%) were aware of the High Court of Australia's definition by which the standard of reasonable care is defined. CONCLUSION: The results from our survey suggest that there is a requirement to enhance the education of medical practitioners to meet the medicolegal requirements and optimise consent.

An Anaphylactoid Reaction to Rattlesnake Envenomation in a Pediatric Patient.

Rattlesnake envenomation causes a spectrum of symptoms and signs, many of which closely resemble an anaphylactic reaction. Development of airway compromise after a snake bite to an extremity is unusual, but has been previously reported. The majority of such reports detail a history of probable sensitization from previous contact with snakes or snake venom. Few reports exist without such previous contact; no reports are of pediatric cases. Here we present a 14-year-old boy with no history of prior snake exposure who presents with an anaphylactoid reaction after a rattlesnake bite.

Quantitative Contrast-Enhanced Ultrasound Parameters in Crohn Disease: Their Role in Disease Activity Determination With Ultrasound.

OBJECTIVE: The primary objective of our study was to examine the association between contrast-enhanced ultrasound (CEUS) parameters and established gray-scale ultrasound with color Doppler imaging (CDI) for the determination of disease activity in patients with Crohn disease. Our secondary objective was to develop quantitative time-signal intensity curve thresholds for disease activity. MATERIALS AND METHODS: One hundred twenty-seven patients with Crohn disease underwent ultrasound with CDI and CEUS. Reviewers graded wall thickness, inflammatory fat, and mural blood flow as showing remission or inflammation (mild, moderate, or severe). If both gray-scale ultrasound and CDI predicted equal levels of disease activity, the studies were considered concordant. If ultrasound images suggested active disease not supported by CDI findings, the ultrasound results for disease activity were indeterminate. Time-signal intensity curves from CEUS were acquired with calculation of peak enhancement (PE), and AUCs. Interobserver variation and associations between PE and ultrasound parameters were examined. Multiclass ROC analysis was used to develop CEUS thresholds for activity. RESULTS: Ninety-six (76%) studies were concordant, 19 of which showed severe disease, and 31 (24%) studies were indeterminate. Kappa analyses revealed good interobserver agreement on grades for CDI (κ = 0.76) and ultrasound (κ = 0.80) assessments. PE values on CEUS and wall thickness showed good association with the Spearman rank correlation coefficient for the entire population (ρ = 0.62, p < 0.01) and for the concordant group (ρ = 0.70, p < 0.01). Multiclass ROC analyses of the concordant group using wall thickness alone as the reference standard showed cutoff points of 18.2 dB for differentiating mild versus moderate activity (sensitivity, 89.0% and specificity, 87.0%) and 23.0 dB for differentiating moderate versus severe (sensitivity, 90% and specificity, 86.8%). Almost identical cutoff points were observed when using ultrasound global assessment as the reference standard: using 18.2 dB to differentiate mild versus moderate activity yielded sensitivity of 89.2% and specificity of 90.9% and using 22.9 dB to differentiate moderate versus severe activity yielded sensitivity of 89.5% and specificity of 83.1%. CONCLUSION: Quantitative CEUS parameters integrated into inflammatory assessments with ultrasound reduce indeterminate results and improve disease activity level determinations.

Supratherapeutic INR During Treatment With Nirmatrelvir/Ritonavir and Warfarin and Acute Illness With COVID-19: A Case Report.

Background: Several studies have examined INR fluctuations using pharmacokinetic (PK) models or post-hoc INR values after completing nirmatrelvir/ritonavir, but further study of the effects of the drug interaction with warfarin during treatment is necessary. Case Summary: Nirmatrelvir/ritonavir is largely utilized in the outpatient setting so data regarding INR trends in hospitalized patients on warfarin is limited. However, many who receive nirmatrelvir/ritonavir outpatient experience difficulty with presenting to clinic for INR checks due to feeling acutely ill along with isolation precautions. We present the case of a patient receiving warfarin and utilizing home INR testing for monitoring. After diagnosis of coronavirus disease of 2019 (COVID-19), she was started on nirmatrelvir/ritonavir on day five after testing positive. Most recent INR prior to the start of therapy was 2.7 and had been stable on the same dose for months prior to infection. On day two of nirmatrelvir/ritonavir, her INR rose to 4.0 on home point of care INR testing. Despite reducing her dose of warfarin by 15%, her INR remained supratherapeutic the day after completing nirmatrelvir/ritonavir (4.0) and for several checks after. One month after completion of therapy, her INR returned to therapeutic levels. Practice Implications: While PK models and case series have hypothesized both potential increases or decreases in INR with the nirmatrelvir/ritonavir and warfarin interaction, COVID-19 infection itself can cause several pharmacodynamic changes which can increase INR, including decreased appetite and, in severe cases, organ dysfunction. This case provides real-world insight into the drug interaction between nirmatrelvir/ritonavir and the drug-disease state interaction between warfarin and COVID-19.

Chronic rhinosinusitis and olfaction after highly effective modulator therapy: The role of individual sinus inflammation.

KEY POINTS: Individual sinus opacification (ISO) is measurable via a convolutional neural network approach. ISO decreased through 2 years after highly effective modulator therapy was initiated. In adults with cystic fibrosis, ISO did not correlate with quality of life or olfaction.

Prioritizing sexual and reproductive health research and care for people with cystic fibrosis: A 2023 workshop report from the Cystic Fibrosis Foundation Sexual Health, Reproduction, and Gender (SHARING) Research Working Group.

BACKGROUND: To address sexual and reproductive health (SRH) concerns among people with cystic fibrosis(PwCF), the CF Foundation created the Sexual Health, Reproduction, and Gender Research (SHARING) Working Group. This report summarizes CF community SRH research priorities and workshop discussions/future study planning. METHODS: Pre-workshop, we distributed a community prioritization survey on CF SRH research/care. During the workshop, we used results and reviewed existing research to establish research priorities and design studies to address identified knowledge gaps. RESULTS: A total of 303 respondents (85 % PwCF, 15 % caregivers) completed the survey. Highly-rated SRH topics were: 1) effects of CF modulator therapy on sex hormones; 2) effects of sex hormones on CF; 3) fertility; 4) pregnancy; and 5) SRH/mental health. Twenty-four workshop participants established the need for further research on sex hormones and CF, optimizing SRH care provision, and fertility/ART. CONCLUSION: SRH is an important and emerging area in CF and thoughtful consideration of community perspectives can ensure that future research is relevant and responsive.

Asystole in 2 Pediatric Patients During Dexmedetomidine Infusion.

INTRODUCTION: Bradycardia is a known side effect of dexmedetomidine. Reports of sinus pauses or asystole, however, are rare. We present 2 cases of pediatric patients who developed asystole on a dexmedetomidine infusion. SUMMARY OF CASES: An 8-week-old male with RSV bronchiolitis and acute hypoxemic respiratory failure was started on dexmedetomidine for sedation at 0.2 mcg/kg/h with a maximum dose of 0.7mcg/kg/h. On Hospital day (HD) 4, on dexmedetomidine at 0.7 mcg/kg/h, he developed intermittent episodes of bradycardia with heart rates in the 60 s. Echocardiogram on HD 6 showed normal function. On HD 7, he began having periods of asystole lasting up to 6 seconds. Dexmedetomidine was discontinued, with the resolution of episodes of asystole after 6 hours. A 27-month-old male with a congenital left diaphragmatic hernia and pulmonary hypertension who had been weaned off sildenafil 6 months earlier underwent re-repair of left diaphragmatic hernia. Postoperatively he remained intubated and paralyzed. Dexmedetomidine was started at 0.3 mcg/kg/h for sedation, with a maximum dose of 1.2 mcg/kg/h. An echocardiogram on HD 3 showed good function with mild to moderate pulmonary hypertension. That evening, with dexmedetomidine at 1.1 mcg/kg/h, he developed a 15 second period of asystole requiring CPR. Dexmedetomidine was discontinued, and he was started on a midazolam infusion with no further episodes. DISCUSSION: Both cases occurred in patients without cardiac conduction defects or on negative chronotropic or sympatholytic medications that have been associated with dexmedetomidine-induced asystole. We hypothesize that both episodes of asystole were due to increased patient-related vagal tone exacerbated by dexmedetomidine.

Family leadership styles and adolescent dietary and physical activity behaviors: a cross-sectional study.

BACKGROUND: Transformational leadership is conceptualized as a set of behaviors designed to inspire, energize and motivate others to achieve higher levels of functioning, and is associated with salient health-related outcomes in organizational settings. Given (a) the similarities that exist between leadership within organizational settings and parenting within families, and (b) the importance of the family environment in the promotion of adolescent health-enhancing behaviors, the purpose of this exploratory study was to examine the cross-sectional relationships between parents' transformational leadership behaviors and adolescent dietary and physical activity behaviors. METHODS: 857 adolescents (aged 13-15, mean age = 14.70 yrs) completed measures of transformational parenting behaviors, healthful dietary intake and leisure-time physical activity. Regression analyses were conducted to examine relationships between family transformational leadership and adolescent health outcomes. A further 'extreme group analysis' was conducted by clustering families based on quartile splits. A MANCOVA (controlling for child gender) was conducted to examine differences between families displaying (a) HIGH levels of transformational parenting (consistent HIGH TP), (b) LOW levels of transformational parenting (consistent LOW TP), and (c) inconsistent levels of transformational parenting (inconsistent HIGH-LOW TP). RESULTS: Results revealed that adolescents' perceptions of family transformational parenting were associated with both healthy dietary intake and physical activity. Adolescents who perceived their families to display the highest levels of transformational parenting (HIGH TP group) displayed greater healthy eating and physical activity behaviors than adolescents who perceived their families to display the lowest levels of transformational parenting behaviors (LOW TP group). Adolescents who perceived their families to display inconsistent levels of transformational parenting behaviors (HIGH-LOW TP group) displayed the same levels of healthy eating behaviors as those adolescents from the LOW TP group. For physical activity behaviors, adolescents who perceived their families to display inconsistent levels of transformational parenting behaviors (HIGH-LOW TP group) did not differ in terms of physical activity than those in either the HIGH TP or LOW TP group. CONCLUSIONS: Family transformational parenting behaviors were positively associated with both healthful dietary intake and leisure-time physical activity levels amongst adolescents. The findings suggest that transformational leadership theory is a useful framework for understanding the relationship between family leadership behaviors and adolescent health outcomes.

Updates in Nutrition Management of Cystic Fibrosis in the Highly Effective Modulator Era.

Attainment and maintenance of good nutrition has been an important aspect of management in cystic fibrosis (CF) for decades. In the era of highly effective modulator therapy for CF, the quality of the nutrients we recommend is increasingly important. Our therapy must support our patients' health for many years beyond what we previously thought. Preventing cardiovascular disease, reducing hyperlipidemia, and optimizing lean body mass for active, longer lives now join the long-standing goal of promoting lung function through nutrition. This chapter summarizes recent developments in nutrition in people with CF, with an eye to the evolution of our practice.

Modelling the pyrenoid-based CO2-concentrating mechanism provides insights into its operating principles and a roadmap for its engineering into crops.

Many eukaryotic photosynthetic organisms enhance their carbon uptake by supplying concentrated CO2 to the CO2-fixing enzyme Rubisco in an organelle called the pyrenoid. Ongoing efforts seek to engineer this pyrenoid-based CO2-concentrating mechanism (PCCM) into crops to increase yields. Here we develop a computational model for a PCCM on the basis of the postulated mechanism in the green alga Chlamydomonas reinhardtii. Our model recapitulates all Chlamydomonas PCCM-deficient mutant phenotypes and yields general biophysical principles underlying the PCCM. We show that an effective and energetically efficient PCCM requires a physical barrier to reduce pyrenoid CO2 leakage, as well as proper enzyme localization to reduce futile cycling between CO2 and HCO3-. Importantly, our model demonstrates the feasibility of a purely passive CO2 uptake strategy at air-level CO2, while active HCO3- uptake proves advantageous at lower CO2 levels. We propose a four-step engineering path to increase the rate of CO2 fixation in the plant chloroplast up to threefold at a theoretical cost of only 1.3 ATP per CO2 fixed, thereby offering a framework to guide the engineering of a PCCM into land plants.

A Method for Orthotopic Transplantation of Lung Cancer in Mice.

Preclinical mouse models of lung cancer have been vital experimental tools to elucidate cancer biology and test novel therapeutic regimens. Two main models are most commonly used-genetically engineered mouse models and xenograft transplantation models. The most common xenograft model employs subcutaneous transplantation of tumor cells. However, the subcutaneous space is a foreign environment to lung cancer cells and does not appropriately model the tumor-stromal interactions of endogenous lung cancers. Here, we present an orthotopic mouse model of lung cancer that utilizes direct injection of cancer cells into the lung parenchyma that allows many potential studies including interactions of lung fibroblast Hedgehog pathway activity and tumor epithelia. The protocol describes this procedure and its potential applications for lung cancer research.

Prospectively evaluating maternal and fetal outcomes in the era of CFTR modulators: the MAYFLOWERS observational clinical trial study design.

INTRODUCTION: Therapeutic advances have markedly increased life expectancy for those with cystic fibrosis (CF), resulting in a median predicted survival over 50 years. Consequently, people with CF (pwCF) are living through their reproductive years and the rate of pregnancy is rapidly rising. Despite the increased relevance of this topic, multicentre studies investigating the association between maternal health and choices made during pregnancy on maternal and fetal outcomes do not exist. Furthermore, there are very limited data on the outcomes following CF transmembrane conductance regulator (CFTR) modulator use during pregnancy and lactation. METHODS AND ANALYSIS: Maternal and Fetal Outcomes in the Era of Modulators (MAYFLOWERS) is a prospective, multicentre observational clinical trial which will enrol approximately 285 pregnant pwCF including those who are modulator ineligible and those who choose to continue or discontinue CFTR modulator therapy during pregnancy and lactation. The primary aim of this 35-month study is to assess whether lung function changes during pregnancy differ based on the continued use of modulators or other factors such as pre-existing comorbid conditions. Secondary objectives include evaluation of pregnancy related and obstetrical complications and changes in mental health. ETHICS AND DISSEMINATION: The design of this study required special consideration of study burden on pregnant and lactating people with chronic illness in the setting of a substantial number of unanswered questions under these conditions. MAYFLOWERS is the first prospective clinical trial examining pregnancy in CF; the outcomes will guide providers on pregnancy management in pwCF and others with chronic respiratory disease.

Pregnancy in cystic fibrosis: Review of the literature and expert recommendations.

Cystic fibrosis (CF) was historically a disease largely afflicting children. Due to therapeutic advancements, there are now more adults with CF than children. In the past decade, medications including Cystic Fibrosis Transmembrane conductance Regulator (CFTR) modulators became available that treat the underlying cause of CF and are dramatically improving lung function as well as quality and quantity of life for people with CF. As a result, more women with CF are becoming pregnant. We gathered a panel of experts in CF care, family planning, high risk obstetrics, nutrition, genetics and women with CF to review current literature on pregnancies and to provide care recommendations for this unique population.

Exposure-Based Methadone and Lorazepam Weaning Protocol Reduces Wean Length in Children.

OBJECTIVE: Determine if a standardized methadone and lorazepam weaning protocol that is based on dose and duration of exposure can reduce the length of opioid and benzodiazepine weaning and shorten hospital stay. METHODS: Retrospective cohort study performed in a 24-bed medical/surgical PICU. A total of 177 patients on opioid and/or benzodiazepine infusions for >3 days were included; 75 patients pre protocol (June 2012- June 2013) were compared with 102 patients post implementation of a standardized weaning protocol of methadone and lorazepam (March 2014-March 2015). The recommended wean was based on duration of infusions of >3 days up to 5 days (no wean), 5 to 13 days (short wean), and ≥14 days (long wean). RESULTS: Median number of days on methadone for patients on opioid infusions for 5 to 13 days was reduced from 8.5 to 5.7 days (p = 0.001; n = 45 [pre], n = 68 [post]) and for patients on opioid infusions for ≥14 days, from 29.7 to 11.5 days (p = 0.003; n = 9 [pre], n = 9 [post]) after protocol implementation. The median number of days on lorazepam for patients on benzodiazepine infusions for 5 to 13 days was reduced from 8.1 to 5.2 days (p = 0.020; n = 43 [pre], n = 55 [post]) and for patients on benzodiazepine infusions for ≥14 days, from 27.4 to 9.3 days (p = 0.011; n = 9 [pre], n = 8 [post]). There was no difference in methadone or lorazepam wean length for patients on 3 to 5 days of infusions. There was no difference in adverse events or hospital length of stay. CONCLUSIONS: A methadone and lorazepam weaning protocol based on patient's exposure to opioids and benzodiazepines (dose and duration) reduces weaning length.

Challenges Faced by Women with Cystic Fibrosis.

Women with cystic fibrosis (CF) face several unaddressed concerns related to their health. These areas of concern include explanations and guidance on a sex disparity in outcomes, timing of puberty, effects of contraception, prevalence of infertility and impact of pregnancy, and prevention of urinary incontinence and osteoporosis. These understudied topics leave women with numerous unanswered questions about how to manage sexual and reproductive health in the setting of CF. Because people with CF are living longer and healthier lives, there is an increasing awareness of these important aspects of care and multiple ongoing studies to address these understudied topics.

Concerns regarding the safety of azithromycin in pregnancy - relevance for women with cystic fibrosis.

Chronic oral azithromycin therapy improves clinical outcomes in people with cystic fibrosis (CF), and is recommended for treatment of CF lung disease. Azithromycin is categorized as pregnancy class B. The data for risk of congenital malformations associated with use of azithromycin during pregnancy ranges from no risk to a small increased risk. As with other chronic medications used to treat CF, potential risk to the infant of use of azithromycin during pregnancy must be weighed against the potential risk to the mother of treatment discontinuation. Women with CF considering pregnancy while on chronic azithromycin should be counseled regarding potential risks and benefits.