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Abstract Background The Gambia has successfully reduced malaria transmission. The human reservoir of infection could further decrease if malaria-infected individuals could be identified by highly sensitive, field-based, diagnostic tools and then treated. Methods A cross-sectional survey was done at the peak of the 2017 malaria season in 47 Gambian villages. From each village, 100 residents were randomly selected for finger-prick blood samples to detect Plasmodium falciparum infections using highly sensitive rapid diagnostic tests (HS-RDT) and PCR. The sensitivity and specificity of the HS-RDT were estimated (assuming PCR as the gold standard) across varying transmission intensities and in different age groups. A deterministic, age-structured, dynamic model of malaria transmission was used to estimate the impact of mass testing and treatment (MTAT) with HS-RDT in four different scenarios of malaria prevalence by PCR: 5, 15, 30, and 60%, and with seasonal transmission. The impact was compared both to MTAT with conventional RDT and mass drug administration (MDA). Results Malaria prevalence by HS-RDT was 15% (570/3798; 95% CI 13.9–16.1). The HS-RDT sensitivity and specificity were 38.4% (191/497, 95% CI 34.2–42.71) and 88.5% (2922/3301; 95% CI 87.4–89.6), respectively. Sensitivity was the highest (50.9%, 95% CI 43.3–58.5%) in high prevalence villages (20–50% by PCR). The model predicted that in very low transmission areas (≤ 5%), three monthly rounds of MTAT with HS-RDT, starting towards the end of the dry season and testing 65 or 85% of the population for 2 consecutive years, would avert 62 or 78% of malaria cases (over 2 years), respectively. The effect of the intervention would be lower in a moderate transmission setting. In all settings, MDA would be superior to MTAT with HS-RDT which would be superior to MTAT with conventional RDT. Conclusion The HS-RDT’s field sensitivity was modest and varied by transmission intensity. In low to very low transmission areas, three monthly rounds per year of MTAT with HS-RDT at 85% coverage for 2 consecutive years would reduce malaria prevalence to such low levels that additional strategies may achieve elimination. The model prediction would need to be confirmed by cluster-randomized trials.

Job analysis, the collection and interpretation of information that describes job behaviors and activities performed by occupants of jobs, can provide nurse administrators with valuable information for redesigning effective and efficient systems of care. [ABSTRACT FROM AUTHOR]

Introduction: Advancements in information technology have facilitated information exchange practices within the Military Health System (MHS), enabling "systems of systems" approaches that broaden and coordinate the set of capabilities available to enhance patient outcomes. This is applicable for MHS modeling and simulation (M&S) applications as well. Learning from successful approaches applied in current interoperability solutions used in the military helps to ensure interoperability practices yield trusted compositions of simulations., Materials and Methods: The use of formal methods provides the rigor necessary to unambiguously communicate these approaches across the MHS community. Here, 3 formal methods are proposed to ensure the harmonization of models and alignment of M&S data needed for simulation interoperability for MHS applications., Results: To clarify considerations relevant for establishing simulation interoperability, the proposed formal methods are examined within a notional example of an injury sustained because of blast exposure. The first method applies the principles of semiotics, addressing the coding of information via syntax and semantics, to understand how to align and transform data across simulations within a composition. The second method applies the concepts of well-specified co-simulations, and the use of different techniques, tools, and algorithms to address the composition and synchronization of M&S components. The third method applies the mathematical branch of model theory to codify expert knowledge about concepts, assumptions, and constraints to ensure conceptual alignment within the simulation composition., Conclusions: Biomedical research must contend with complexity inherent to computational human body modeling, enlisting expert knowledge from multiple domains supporting the development of cross-disciplinary research tools that resolve research foci and associated differences in underlying theories, methods, and applied tools. This is closely related to the broader context of digital engineering for military systems engineering., (© The Association of Military Surgeons of the United States 2024. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site–for further information please contact journals.permissions@oup.com.)

Mycobacteria adapt to infection stresses by entering a reversible non-replicating persistence (NRP) with slow or no cell growth and broad antimicrobial tolerance. Hypoxia and nutrient deprivation are two well-studied stresses commonly used to model the NRP, yet little is known about the molecular differences in mycobacterial adaptation to these distinct stresses that lead to a comparable NRP phenotype. Here we performed a multisystem interrogation of the Mycobacterium bovis BCG (BCG) starvation response, which revealed a coordinated metabolic shift away from the glycolysis of nutrient-replete growth to depletion of lipid stores, lipolysis, and fatty acid ß-oxidation in NRP. This contrasts with BCG's NRP hypoxia response involving a shift to cholesterol metabolism and triglyceride storage. Our analysis reveals cryptic metabolic vulnerabilities of the starvation-induced NRP state, such as their newfound hypersensitivity to H 2 O 2 . These observations pave the way for developing precision therapeutics against these otherwise drug refractory pathogens., (© 2024. The Author(s).)

Queuosine (Q) is a conserved hypermodification of the wobble base of tRNA containing GUN anticodons but the physiological consequences of Q deficiency are poorly understood in bacteria. This work combines transcriptomic, proteomic and physiological studies to characterize a Q-deficient Escherichia coli K12 MG1655 mutant. The absence of Q led to an increased resistance to nickel and cobalt, and to an increased sensitivity to cadmium, compared to the wild-type (WT) strain. Transcriptomic analysis of the WT and Q-deficient strains, grown in the presence and absence of nickel, revealed that the nickel transporter genes (nikABCDE) are downregulated in the Q- mutant, even when nickel is not added. This mutant is therefore primed to resist to high nickel levels. Downstream analysis of the transcriptomic data suggested that the absence of Q triggers an atypical oxidative stress response, confirmed by the detection of slightly elevated reactive oxygen species (ROS) levels in the mutant, increased sensitivity to hydrogen peroxide and paraquat, and a subtle growth phenotype in a strain prone to accumulation of ROS., (© The Author(s) 2022. Published by Oxford University Press.)

Diagnoses of depression, anxiety, or other mental illness capture just one aspect of the psychosocial elements of the perinatal period. Perinatal loss; trauma; unstable, unsafe, or inhumane work environments; structural racism and gendered oppression in health care and society; and the lack of a social safety net threaten the overall well-being of birthing people, their families, and communities. Developing relevant policies for perinatal mental health thus requires attending to the intersecting effects of racism, poverty, lack of child care, inadequate postpartum support, and other structural violence on health. To fully understand and address this issue, we use a human rights framework to articulate how and why policy makers must take progressive action toward this goal. This commentary, written by an interdisciplinary and intergenerational team, employs personal and professional expertise to disrupt underlying assumptions about psychosocial aspects of the perinatal experience and reimagines a new way forward to facilitate well-being in the perinatal period.

Protein synthesis rate and accuracy are tightly controlled by the cell and are essential for proteome homoeostasis (proteostasis); however, the full picture of how mRNA translational factors maintain protein synthesis accuracy and co-translational protein folding are far from being fully understood. To address this question, we evaluated the role of 70 yeast tRNA-modifying enzyme genes on protein aggregation and used mass spectrometry to identify the aggregated proteins. We show that modification of uridine at anticodon position 34 (U34) by the tRNA-modifying enzymes Elp1, Elp3, Sml3 and Trm9 is critical for proteostasis, the mitochondrial tRNA-modifying enzyme Slm3 plays a fundamental role in general proteostasis and that stress response proteins whose genes are enriched in codons decoded by tRNAs lacking mcm 5 U 34 , mcm 5 s 2 U 34 , ncm 5 U 34 , ncm 5 Um 34 , modifications are overrepresented in protein aggregates of the ELP1, SLM3 and TRM9 KO strains. Increased rates of amino acid misincorporation were also detected in these strains at protein sites that specifically mapped to the codons sites that are decoded by the hypomodified tRNAs, demonstrating that U 34 tRNA modifications safeguard the proteome from translational errors, protein misfolding and proteotoxic stress.

Colorectal cancer (CRC) is the second-most common cause of cancer-related mortality. The most important prognostic factors are lymph node (LN) involvement and extranodal metastasis. Our objective is to investigate the interactions between CD133(+)CXCR4(+) (CXC receptor 4) colorectal cancer tumor-initiating cells (Co-TICs) and the LN stromal microenvironment in human CRC extranodal metastasis. We established a unique humanized orthotopic xenograft model. Luciferase-tagged CRC cell lines and human cancer cells were injected intrarectally into nonobese diabetic/SCID mice. Mesenteric LN stromal cells, stromal cell line HK, or CXCL12 knockdown HK (HK-KD-A3) cells were coinoculated with CRC cells. Tumor growth and metastasis were monitored by bioluminescent imaging and immunohistochemistry. We found that this model mimics the human CRC metastatic pattern with CRC cell lines or patient specimens. Adding LN stromal cells promotes CRC tumor growth and extranodal metastasis (P < 0.001). Knocking down CXCL12 impaired HK cell support of CRC tumor formation and extranodal metastasis. When HK cells were added, sorted CD133(+)CXCR4(+) Co-TICs showed increased tumor formation and extranodal metastasis capacities compared to unseparated and non-Co-TIC populations. In conclusion, both Co-TIC and LN stromal factors play crucial roles in CRC metastasis through the CXCL12/CXCR4 axis. Blocking Co-TIC/LN-stromal interactions may lead to effective therapy to prevent extranodal metastasis., (© FASEB.)

Introduction: Colorectal cancer (CRC) stem cells or tumor-initiating cells (Co-TIC) are implicated in both cancer recurrence and extranodal metastasis. CD133 and CXCR4 are specific cell surface markers that are indicators of Co-TIC. The presence of lymph node (LN) metastases is one of the strongest negative prognostic factors for CRC patients. We examined the relationship between the Co-TIC markers CD133 and CXCR4 and LN involvement in CRC., Methods: CRC cells were isolated via enzymatic digestion. CD133(+), CXCR4(+), and double-positive CRC cells were detected by fluorescence-activated cell sorting analysis. The percentages of CD133(+), CXCR4(+), and double-positive cells were identified and correlated to the number and percentage of positive LN on staging., Results: Twenty-seven samples underwent fluorescence-activated cell sorting analysis. The mean percentage of CD133(+) cells was 3.94% (range 0.15%-19.06%). The mean percentage of CXCR4(+) cells was 6.15% (range 0%-27.11%). The mean percentage of CD133(+)CXCR4(+) cells was 0.45% (range 0%-2.08%). Thirteen patients had LN metastasis: 8 N1 disease and 5 N2 disease. The correlation coefficients between the percentage of Co-TIC marker-positive cells and percentage of positive LN were r = 0.58 (P = 0.0016) for CD133(+) cells, r = 0.36 (P = 0.5868) for CXCR4(+) cells, and r = 0.56 (P = 0.0022) for double-positive cells., Discussion: Our results show CD133(+) and CD133(+)CXCR4(+) cancer cells correlate with the presence of LN metastasis in CRC. Further studies will examine whether these markers can give consistent prognostic information and may help to develop novel diagnostic and therapeutic options., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objective: The hepatorenal index has been reported to be a sensitive and noninvasive test to quantify steatosis, but it is cumbersome and time-consuming and requires specialized software. The aim of this study was to improve and simplify the hepatorenal index calculation and determine whether it is an effective tool for differentiating patients with steatosis from those without steatosis, thereby eliminating the need for biopsy in a large number of patients., Materials and Methods: One hundred one patients who had undergone ultrasound-guided percutaneous liver biopsy at our institution were selected from a patient database. Patients with renal disease, patients with liver masses, and patients whose liver and right kidney were not included on the same image were excluded. Images were acquired with high-resolution ultrasound, and the hepatorenal index was calculated using freeware based on comparison of hepatic and renal brightness., Results: Of the 101 patients, 63 had 5% or less steatosis and 38 had more than 5% steatosis. Using freeware available online from the National Institutes of Health, we calculated hepatorenal index values for all patients. Our data showed a strong correlation between the hepatorenal index and percentage of fat (r = 0.71, p < 0.0001). A hepatorenal index of 1.28 or greater had a 100% sensitivity for identifying more than 5% fat, 54% specificity, 0.57 positive predictive value, and 1.0 negative predictive value. If this method had been used prospectively to select patients for biopsy in our sample, 34% of biopsies could have been avoided., Conclusion: The hepatorenal index is a simple, reliable, and cost-effective screening tool for identifying patients who should not undergo liver biopsy for evaluation of steatosis.

Squamous cell carcinoma of the pancreas is a rare pancreatic malignancy. We describe the case of a female who presented with abdominal pain and was found to have a pancreatic mass on imaging. The diagnosis of pancreatic squamous cell carcinoma was established by endoscopic ultrasound-guided fine needle aspiration of the mass. To the best of our knowledge, this is only the second case report in the medical literature in which endoscopic ultrasound-guided fine needle aspiration was used for a cell-type specific diagnosis of primary pancreatic squamous cell carcinoma.

Colorectal cancer (CRC) is the third most common malignancy and the second leading cause of cancer-related deaths in America. Nearly two thirds of newly diagnosed CRC cases include lymph node (LN) involvement, and LN metastasis is one of the strongest negative prognostic factors for CRC. It is thought that CRC tumors contain a small population of drug-resistant CRC tumor-initiating cells (Co-TICs) that may be responsible for cancer recurrence. To evaluate the effects of the LN stromal cells on Co-TICs, we established a unique xenoplant model using CRC cells isolated by enzymatic digestion from consented patient specimens, HT-29 cells, HCA-7 cells, and LN stromal cell line HK cells. We found that HK cells and HK cell-conditioned media enhanced CRC tumor formation and tumor angiogenesis. Cells expressing CD133(+) and the stromal cell-derived factor 1α (SDF-1α) receptor CXCR4 were enriched in chemotherapeutic-resistant CRC cells. CD133(+)CXCR4(+) Co-TICs isolated from patient specimens are more tumorigenic than unsorted tumor cells. Furthermore, the inhibitors specific to HK cell-derived SDF-1α reduced tumor formation and tumor angiogenesis. Our results have demonstrated a role for Co-TICs in tumor growth and defined the influence of LN stromal cells on Co-TICs. We have identified a major Co-TIC/LN microenvironment-specific mechanism for CRC resistance to chemotherapeutic agents and established experimental platforms for both in vitro and in vivo testing, indicating that SDF-1α and its receptor, CXCR4, may be targets for clinical therapy.

We have synthesized a fused tetraanthracenylporphyrin by oxidation of a meso-anthracenyl nickel(II) porphyrin with FeCl(3). This compound exhibits an intense red-shifted absorption spectrum (λ(max) = 1417 nm; ε = 1.2 × 10(5) M(-1) cm(-1)) and a small electrochemical HOMO-LUMO gap (0.61 eV). The crystal structure shows that it forms π-stacked dimers with a short Ni···Ni distance (3.32 Å).

Synthesis of fused bis-anthracene porphyrin monomers and dimers has been achieved by oxidative ring closure using FeCl(3) and Sc(OTf)(3)/DDQ, respectively. The fused compounds display red-shifted absorption spectra with maxima in the near-IR at 973 and 1495 nm, respectively, and small electrochemical HOMO-LUMO gaps. The crystal structure of the fully fused bis-anthracene porphyrin shows that it has a regular planar pi-system.

Synthesis of beta,meso,beta-anthracene triply fused and beta,meso-anthracene doubly fused porphyrins has been achieved via oxidative intramolecular ring closure of meso-(9-anthryl)porphyrins and meso-(1-anthryl)porphyrins, respectively. Fusion was only possible when the anthracene carried electron-donating alkoxy substituents. The fused porphyrins exhibit strongly red-shifted UV-vis absorption spectra and reduced electrochemical HOMO-LUMO gaps (relative to the unfused tetraaryl porphyrin precursor).

A transgenic animal can be defined as an organism that has undergone a stable modification of genotype as a result of genetic manipulation. Such animals are being increasingly employed as research and development tools by both academic and commercial institutions. The primary methods by which transgenic animals can be generated will be described. The relative merits of the approaches will be illustrated, as will their potential use in the discovery and development of novel therapeutic entities.

A non-sporulating mutant (whiB218) of Streptomyces coelicolor A3(2), which proved to contain a deletion of more than 5 kb of DNA including whiB, was complemented by a small cloned DNA fragment, deduced from DNA sequencing to encode a protein of only 87 amino acids. This protein would bear some similarities to transcription factors, including an acidic, somewhat amphipathic alpha-helical region predicted near its N-terminus, and a basic alpha-helical region predicted at its C-terminus. A point mutation (whiB70) giving a phenotype indistinguishable from that of the whiB218 deletion mutant would cause a leucine to proline change at the start of the latter region. The whiB homologue from the closely related species S. lividans differed at only one base from its S. coelicolor counterpart, and would specify an identical polypeptide.

Streptomyces coelicolor produces spores whose development of a grey colour requires the activity of the whiE locus. The cloned whiE locus was identified after mobilization into a whiE mutant of a library of S. coelicolor DNA inserted into a transmissible plasmid vector. The whiE region of the cloned DNA was localized both by subcloning and by mutagenesis of the cloned DNA with the Streptomyces transposon Tn4560. Nucleotide sequencing of this region revealed seven open reading frames, of which six show homology at the level of deduced gene products with genes involved in the synthesis of polyketide antibiotics. A previously described S. coelicolor DNA segment encoding biosynthesis of a brown pigment (Horinouchi and Beppu, 1985) corresponds to the cloned whiE DNA. It is proposed that whiE is normally expressed only in the aerial hyphae, where the biosynthetic product is responsible for spore colour.

Two independent mutants defective in glutathione reductase (EC 1.6.4.2) were isolated in an Escherichia coli K12 strain lysogenized with bacteriophage Mu. The prophage was lost (and the ability to reduce glutathione regained) by 32% of the xylose-positive transductants when T4GT7 was used as the vector, but the markers were not cotransduced by P1. Similarly, the prophage site and malA were cotransduced by T4GT7 but not by P1. The gor gene maps between min 77 and 78 on the E. coli genome, and the mutation causes no growth defect.

5'-Deoxyadenosylcobalamin-dependent methylmalonyl-CoA mutase was purified to homogeneity from Propionibacterium shermanii by a simplified procedure. The native enzyme has an apparent Mr of 165,000, similar to the enzyme from other sources but larger than previously reported. It consists of two non-identical subunits, of Mr 79,000 and 67,000 respectively. The smaller subunit is apparently not a proteolytic fragment of the larger one. The final preparation usually contained some inactive mutase, bearing a tenaciously bound cobalamin species. This protein proved to be readily separable from apoenzyme by fast protein liquid chromatography on anion-exchange columns.

The structural genes coding for both subunits of adenosylcobalamin-dependent methylmalonyl-CoA mutase from the Gram-positive bacterium Propionibacterium shermanii have been cloned, with the use of synthetic oligonucleotides as primary hybridization probes. The genes are closely linked and are transcribed in the same direction. Nucleotide sequence analysis of 4.5 kb of DNA encompassing both genes allowed us to infer the complete amino acid sequence of the two subunits: the beta-subunit is the product of the upstream gene, and consists of 638 amino acid residues (Mr 69465) and the alpha-subunit consists of 728 amino acid residues (Mr 80,147). There is a very close structural homology between the two subunits, reflecting the probable duplication of a common ancestral gene. A sequence present only in the alpha-subunit is significantly homologous to a portion of the sequence of the methylmalonyl-CoA-binding subunit of transcarboxylase from P. shermanii [Samols, Thornton, Murtif, Kumar, Haase & Wood (1988) J. Biol. Chem. 263, 6461-6464], and this homologous region may form part of the CoA ester-binding site in both enzymes.