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Abstract: We present a case of a professional basketball player who suffered from nonunion bilateral chronic tibial fractures, successfully treated with ultrasound-guided intraosseous injection with bone marrow aspirate concentrate. The patient was able to return to play full time after recovery from the procedure., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background and Aims: Biases in healthcare pose challenges for inflammatory bowel disease (IBD) patients from underrepresented races and ethnicities. Our study aimed to assess the quality of and access to care among underrepresented racial and ethnic populations using a diverse database., Methods: We used the OneFlorida Data Trust, representing over half of Florida's population. We performed a retrospective study from 2012 to 2020. Advanced IBD therapies included a prescription of at least 1 biologic agent or tofacitinib. Disease activity markers included C-reactive protein (CRP), hemoglobin (Hgb), albumin, and white blood cell (WBC). Regression analyses compared the rates of medication use, healthcare utilization, and disease severity by race and ethnicity. Geographic distribution of advanced IBD therapy was analyzed at the county level., Results: Our study included 10 578 patients. Hispanic patients utilized more biologics than non-Hispanic White (NHW) patients (odds ratio [OR]: 1.3, P < .0001). Non-Hispanic Black patients utilized more steroids than NHW (OR: 1.2, P = .0004). Hispanics had fewer visits to emergency departments (EDs) and fewer admissions compared with NHW (OR: 0.7 and 0.6, respectively; P < .0001). Non-Hispanic Black patients visited ED more frequently than NHW patients (OR: 1.3, P < .0001). Hispanics had lower disease activity markers than NHW based on CRP (OR: 0.5, P = .005), Hgb (OR: 0.4, P < .0001), albumin (OR: 0.7, P < .0001), and WBC (OR: 0.5, P < .0001). Geographic distribution of advanced IBD therapy showed clustered areas in southern and northern Florida., Conclusions: Our data show an improved access to care pattern in Hispanic patients. However, disparities still exist, and this is evident in the healthcare utilization trends observed among non-Hispanic Black patients., (© The Author(s) 2024. Published by Oxford University Press on behalf of Crohn’s & Colitis Foundation. 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.)

Background: In National Collegiate Athletic Association (NCAA) soccer athletes, men have higher rates of hip and groin strains, whereas women have higher rates of knee ligament injuries. Strength imbalances of the hip and thigh, specifically in agonist-antagonist muscles, are known risk factors for these injuries., Objective: To perform hip and thigh strength assessments in NCAA soccer players to evaluate for differences between genders and correlations with gender-specific injury patterns., Design: With a handheld dynamometer, weight-normalized isometric strength of six muscle groups (hip abductors, hip adductors, hip flexors, hip extensors, knee flexors, knee extensors) was calculated in NCAA soccer players. The strength ratio of each agonist-antagonist muscle was also calculated (hip abductors/adductors, hip flexors/extensors, knee extensors/flexors)., Participants: Thirty-six NCAA soccer players (18 men, 18 women) from a single NCAA Division III institution., Interventions: Not applicable., Main Outcome Measures: Weight-normalized strength of six muscle groups and their agonist-antagonist strength ratios were compared between genders using linear mixed-effects models., Results: Compared with male players, female players had decreased weight-normalized strength for hip abduction (0.170 vs. 0.204, p = .012) and hip extension (0.172 vs. 0.211, p = .021). Otherwise, weight-normalized strength was similar between genders. When comparing agonist-antagonist strength ratios, there was a significant difference between female and male players for hip flexion:extension (1.70 vs. 1.35, p = .008), whereas the hip abduction: adduction ratio did not reach statistical significance (1.45 vs. 1.62, p = .080)., Conclusions: NCAA male and female soccer players had different hip strength profiles that fit their injury patterns. Male NCAA soccer players have higher rates of hip and groin strains, and men in the cohort had strength ratios that were deficient in the hip flexors and adductors compared with women. Female NCAA soccer players have higher rates of knee sprains and anterior cruciate ligament tears, and women in the cohort had strength ratios that were deficient in the hip abductors and extensors, which function to stabilize the knee. These strength disparities could be the focus of future gender-specific soccer injury prevention programs., (© 2024 American Academy of Physical Medicine and Rehabilitation.)

Myasthenia Gravis (MG) is an autoimmune disease associated with severe neuromuscular weakness. Diagnostic confirmation of MG is typically delayed and secured in about 85% and 50% of patients with generalized and ocular MG, respectively with serum antibodies. We have identified a sensitive and specific diagnostic biomarker for various MG serotypes with quantitative proteomics. Serum proteomes of 18 individuals (MG patients, healthy controls (HC), Rheumatoid Arthritis (RA) were quantified in a pilot study and occurrence of high residual fibrinogen was validated by immunoblotting and further investigated by targeted mass spectrometry on the sera of 79 individuals (31 MG of various serotypes, 30 HC, 18 RA). Initial proteomic analysis identified high residual fibrinogen in MG patient sera which was then validated by antibody-based testing. Subsequently, a blinded study of independent samples showed 100% differentiation of MG patients from controls. A final serological quantification of 14 surrogate peptides derived from α-, β-, and γ-subunits of fibrinogen in 79 individuals revealed fibrinogen to be highly specific and 100% sensitive for MG (p < 0.00001), with a remarkable average higher abundance of > 1000-fold over control groups. Our unanticipated discovery of high levels of residual serum fibrinogen in all MG patients can secure rapid bedside diagnosis of MG., (© 2023. The Author(s).)

Background and Aims: Data on how to teach endosonographers needle-based confocal laser endomicroscopy (nCLE)-guided histologic diagnosis of pancreatic cystic lesions (PCLs) are limited. Hence, we developed and tested a structured educational program to train early-career endosonographers in nCLE-guided diagnosis of PCLs., Methods: Twenty-one early-career nCLE-naïve endosonographers watched a teaching module outlining nCLE criteria for diagnosing PCLs. Participants then reviewed 80 high-yield nCLE videos, recorded diagnoses, and received expert feedback (phase 1). Observers were then randomized to a refresher feedback session or self-learning at 4 weeks. Eight weeks after training, participants independently assessed the same 80 nCLE videos without feedback and provided histologic predictions (phase 2). Diagnostic performance of nCLE to differentiate mucinous versus nonmucinous PCLs and to diagnose specific subtypes were analyzed using histopathology as the criterion standard. Learning curves were determined using cumulative sum analysis., Results: Accuracy and diagnostic confidence for differentiating mucinous versus nonmucinous PCLs improved as endosonographers progressed through nCLE videos in phase 1 (P < .001). Similar trends were observed with the diagnosis of PCL subtypes. Most participants achieved competency interpreting nCLE, requiring a median of 38 assessments (range, 9-67). During phase 2, participants independently differentiated PCLs with high accuracy (89%), high confidence (83%), and substantial interobserver agreement (κ = .63). Accuracy for nCLE-guided PCL subtype diagnoses ranged from 82% to 96%. The learned nCLE skills did not deteriorate at 8 weeks and were not impacted by a refresher session., Conclusions: We developed a practical, effective, and durable educational intervention to train early-career endosonographers in nCLE-guided diagnosis of PCLs., Competing Interests: Disclosure The following authors disclosed financial relationships: J. D. Machicado: Speaker for Mauna Kea Technologies. S. G. Krishna: Speaker for and research support from Mauna Kea Technologies. B. Napoleon: Speaker for Mauna Kea Technologies. All other authors disclosed no financial relationships., (Copyright © 2023 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Late adolescents and young adults (AYA) with inflammatory bowel disease (IBD) are a vulnerable population as they transition to adult healthcare. We aim to provide a real-world data on their healthcare utilization patterns and medication use through a large database., Methods: We performed a retrospective cohort study from January 1, 2012, to June 30, 2020, using OneFlorida Data-Trust, an electronic health record-based data repository representing over half of the Florida population. Outcomes of interest included demographics, healthcare utilization, medications, and disease severity. Chi-square tests and logistic regression were used to compare the rates of medication use, healthcare utilization, and disease severity by age groups., Results: The number of patients who met our inclusion criteria was 10,578 with 2731 (25.8%) in the 17-25-year-old group. AYA patients had fewer ambulatory visits vs children (90% vs 95%; P value <.05). AYA patients were admitted more frequently from emergency facilities vs children (22.3% vs 10.9%; P value <.05). AYA patients received steroids more often than adults and younger patients (48.9% vs 45.3 vs 44.3% P value <.05, respectively). AYA patients received more narcotic (41.1% vs 22.3 % P value <.05) and antidepressant prescriptions (15.9% vs 9.5%; P value <.05) compared with children. With advancing age, a decrease in biologic use was noted (51% vs 40% vs 25.4% P value <.05, respectively)., Conclusion: AYA patients with IBD have higher rates of hospital admissions from emergency department, fewer ambulatory health visits and they receive more steroids compared to children. Our study demonstrates the need for age-specific IBD programs for AYA patients., (© 2023 The Authors.)

Background: Low back pain (LBP) is a common cause of disability worldwide; multiple causes and risk factors have been proposed in the genesis of back pain. Some studies reported an association between diastasis recti abdominis (DRA), a surrogate for decreased core strength muscle, and low back pain. We aimed to investigate the relationship between DRA and LBP through a systematic review., Methods: A systematic review of the literature of clinical studies in English literature was conducted. PubMed, Cochrane, and Embase databases were used to conduct the search up to January 2022. The strategy included the following keywords: "Lower Back Pain" AND "Diastasis Recti" OR "Rectus abdominis" OR "abdominal wall" OR "paraspinal musculature"., Results: From 207 records initially found, 34 were suitable for full review. Thirteen studies were finally included in this review, with a total of 2,820 patients. Five studies found a positive association between DRA and LBP (5 of 13 = 38.5%) whereas 8 studies did not find any association between DRA and LBP (8 of 13 = 61.5%)., Conclusions: Of the studies included in this systematic review, 61.5% did not find an association between DRA and LBP whereas a positive correlation was observed in 38.5% of studies included. Based on the quality of the studies included in our review, better studies are warranted to understand the association between DRA and LBP., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Metallic or metal oxide-based nanoparticles have the potential to inactivate viruses. Among various metals, copper has shown edge over others. One of the rapidly evolving areas is to combine nanoscience for production of self-sanitizing antiviral surfaces. In this study, we designed antiviral-coated fabrics to combat the spread of viruses. Copper oxide nanoparticles were sonochemically synthesized and subsequently deposited using the dip-coat process to modify the surface of fabric. The morphology and structure of uncoated and coated fabrics were examined by scanning electron microscopy, X-ray diffraction, FTIR, and elemental analysis. The findings show that small, agglomerated rugby ball structures made of copper oxide (CuO) nanoparticles (16 ± 1.6 nm, according to the Scherrer equation) develop on the surface of fabric, resulting in nano-embossing and a hydrophobic (contact angle > 140°) surface. The CuO-coated fabric yielded the maximum zone of inhibition for antibacterial activity. The virucidal activity (against human adenovirus-B) of CuO nanoparticle-fabricated fabric against adenovirus shows decreased 99.99% according to the ISO 18184 testing standard. With the dip and dry approach, any textile industry can use the simple coating procedure without having to change its textile operations. This fabric can be widely used in the face mask, clothing, bedding, and aprons, and the coating remains efficient over more than 25 washes., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Acute respiratory tract infections (ARIs) are a major cause of morbidity and mortality in under-five children worldwide. Assam has around 2500 river islands (locally called Chars/Chaporis) in the Brahmaputra River with socioeconomically deprived inhabitants lacking access to basic health-care facilities. A community-based cross-sectional study was carried out among 380 under-five children living in the Char areas of Tinsukia District to estimate the prevalence of ARI and determine the associated risk factors. The prevalence of ARI among under-five children was found to be 56.32%. Prevalence was significantly higher among children living in Dibru-Saikhowa island, with families having >2 children, belonging to socioeconomic class 5 (modified BG Prasad scale), having a positive history of smoking or ARI in family members, having homes with attached kitchens or using wood for cooking, inadequate ventilation or overcrowding and residences of katcha ghars., Competing Interests: None

Background: Cutaneous Adverse Drug Reactions (ADRs) are common and pose a serious challenge to physicians, especially in cases when the patient has many comorbidities, is polypharmacy, or self-administers over-the-counter medications., Objective: The objective of this study is to analyze the clinical pattern and incidence of cutaneous ADRs and perform causality assessment using the WHO-UMC scale and Naranjo's scale. The severity of the reactions was determined by the Hartwig scale., Methods: This was conducted as a prospective observational study in patients admitted to SRM Medical College, Kattankulathur, Tamil Nadu, India, between November 2016 to August 2018 after obtaining Institutional Ethics Committee clearance of all adverse drug reactions reported at the hospital., Results: Of the 158 ADRs reported during the time period, 101 were cutaneous ADRs, of which the most common presentation was maculopapular rash (n=42; 41.58%). The most common drugs which produced cutaneous adverse reactions were antimicrobials (n=58; 57.42%) followed by NSAIDs (n=35; 34.6%). The causality assessment as per the Naranjo scale yielded 3.96% (4) cases as definite, 81.18% (82) as probable, and 14.85% (15) as possible, whereas the WHO scale yielded 9 (89.10%) certain, 64 (63.36%) probable and 28 (27.72%) possible cases. The severity of the cases determined as per the Hartwig scale yielded 82.17% cases as mild and 17.82% as moderate., Conclusion: It is important to recognise the ADRs at the right time and exert caution in future use. This can minimise harm to the patient both physically and financially and improve the outcome of the treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Introduction : Myasthenia gravis (MG) is an antibody-mediated disease with diverse serology and clinical presentation. Currently, MG is managed by untargeted immunomodulatory agents. About 15% patients are refractory to these therapies. Several novel and targeted treatments are on the horizon. Rituximab, a monoclonal antibody, is reported to be highly effective with widespread oof-label usage in MG, particularly in patients with antibody against muscle-specific kinase or refractory disease. However, a recent trial showed negative results. Compared to conventional oral immunosuppressive therapies used in MG, Rituximab has several benefits. Regular hematological monitoring is not required though serious side effects can occur. Current status of Rituximab in MG and newer immunosuppressants is discussed. Areas explored : Biologic features, clinical effectiveness, safety profile, and newer preparations of Rituximab. Expert opinion : Rituximab provides a promising option for management of MG, particularly in patients with muscle-specific kinase antibodies or those with refractory disease. Several knowledge gaps remain due to scarcity of data from randomized controlled studies. Despite lack of regulatory approval Rituximab has found widespread usage in MG. Large, well-designed studies are needed to assess the comparative efficacy of Rituximab and its optimal regimen in MG.

In-hospital arrests are uncommon in pediatrics, making it difficult to identify the risk factors for unrecognized deterioration and to determine the effectiveness of rapid response systems. An emergency transfer (ET) is a transfer from an acute care floor to an intensive care unit (ICU) where the patient received intubation, inotropes, or ≥3 fluid boluses in the first hour after arrival or before transfer. Improvement science work has reduced ETs, but ETs have not been validated against important health outcomes. This case-control study aimed to determine the predictive validity of an ET for outcomes in a free-standing children's hospital. Controls were matched in terms of age, hospital unit, and time of year. Patients who experienced an ET had a significantly higher likelihood of in-hospital mortality (22% vs 9%), longer ICU length of stay (4.9 vs 2.2 days), and longer posttransfer length of stay (26.4 vs 14.7 days) compared with controls (P < .03 for each).

Paneth cells (PCs) are epithelial cells found in the small intestine, next to intestinal stem cells (ISCs) at the base of the crypts. PCs secrete antimicrobial peptides (AMPs) that regulate the commensal gut microbiota. In contrast, little is known regarding how the enteric microbiota reciprocally influences PC function. In this study, we sought to characterize the impact of the enteric microbiota on PC biology in the mouse small intestine. This was done by first enumerating jejunal PCs in germ-free (GF) versus conventionally raised (CR) mice. We next evaluated the possible functional consequences of altered PC biology in these experimental groups by assessing epithelial proliferation, ISC numbers, and the production of AMPs. We found that PC numbers were significantly increased in CR versus GF mice; however, there were no differences in ISC numbers or cycling activity between groups. Of the AMPs assessed, only Reg3γ transcript expression was significantly increased in CR mice. Intriguingly, this increase was abrogated in cultured CR versus GF enteroids, and could not be re-induced with various bacterial ligands. Our findings demonstrate the enteric microbiota regulates PC function by increasing PC numbers and inducing Reg3γ expression, though the latter effect may not involve direct interactions between bacteria and the intestinal epithelium. In contrast, the enteric microbiota does not appear to regulate jejunal ISC census and proliferation. These are critical findings for investigators using GF mice and the enteroid system to study PC and ISC biology.

Intracranial mucormycosis is a very unusual presentation of an infection after a depressed skull fracture due to an assault. Only sporadic cases have been reported in the literature previously. A 30-year-old male with a traumatic brain injury following an assault, status-post debridement and elevation of a depressed skull fracture, was discharged home several weeks postoperatively. A CT scan of the head with contrast was obtained due to mental status changes and revealed an enhancing ring-shaped lesion in the right frontal lobe consistent with a brain abscess. The patient was taken to the operating room for image-guided excisional biopsy of the lesion, with pathology revealing mucormycosis., Competing Interests: The authors have declared that no competing interests exist.

The last decade has seen considerable advances in the treatment of anxiety disorders in children and adolescents and a considerable expansion of the evidence base for psychopharmacologic in this population. The extant data suggest that, for fear-based anxiety disorders ( e.g. , generalized anxiety disorder, social phobia/social anxiety disorder, and separation anxiety disorder), selective serotonin reuptake inhibitors (SSRIs) and selective serotonin norepinephrine reuptake inhibitors (SSNRIs) are well tolerated and offer considerable benefit. However, the salutary effects of SSRIs and SSNRIs in pediatric anxiety disorders are consistently amplified by the addition of psychotherapy, particularly in individuals with social anxiety disorder. Additionally, several key demographic and clinical factors, including male sex, non-minority status, and better family functioning and younger age predict greater symptomatic improvement in youth with fear-based anxiety disorders. Thus, current data suggest that in addition to several forms of psychotherapy, including cognitive-behavioral therapy (CBT), SSRIs and SSNRIs are efficacious in the treatment of these conditions in youth and that CBT + an SSRI may be associated with greater improvement than would be expected with either treatment as monotherapy. Finally, given that some children and adolescents may exhibit partial response to current pharmacotherapies, benzodiazepines, anti-histamines and other agents may have adjunctive roles, despite a lack of data in terms of large, randomized controlled trials., Competing Interests: Farah S. Hussain and Eric T. Dobson declare that they have no conflict of interest. Jeffrey R. Strawn reports grants and other from National Institute of Mental Health, grants from Shire, grants from Eli Lilly, grants from Forest Research Institute, grants from Lundbeck, grants from Edgemont, other from Neuronetics,royalties from Springer Publishing, material support from Assurex, outside the submitted work.

Objective: To determine the diagnostic efficiency of thallium-201 single photon emission computed tomography (SPECT) and Epstein-Barr virus (EBV) polymerase chain reaction (PCR) in the differentiation of primary central nervous system lymphoma (PCNSL) from other central nervous system processes in patients with HIV/AIDS., Design/methods: Over 10 years, 68 thallium-201 SPECT scans were performed on neurologically symptomatic HIV+ patients with focal lesions on CT or MRI at the Johns Hopkins Hospital. Diagnoses were then established by either autopsy, biopsy, or clinical response to anti-toxoplasmosis therapy. Patients were categorized prior to a prospective clinical reading of the SPECT scans by nuclear medicine physicians., Results: In our patient sample overall, the diagnostic efficiency of thallium-201 SPECT was 79%. The diagnostic accuracy of EBV PCR testing alone in a subset of 22 patients in our study that had CSF analyzed was 73%. However, when both positive EBV PCR and positive thallium-201 SPECT results were used together, the diagnostic accuracy improved to 100% based on a sample of 13 patients where EBV PCR and SPECT imaging results were concordant. , Conclusion: Thallium-201 SPECT has a relatively high positive predictive value with regards to the diagnosis of PCNSL, which suggests that patients with positive results could undergo empiric radiation treatment without resorting to brain biopsy. However, the predictive value can be increased by testing for CSF EBV using PCR. Alternatively, if CSF cannot be safely obtained because of mass effect, we believe that these data still suggest that empiric radiation treatment should be considered when discussing treatment options with patients with a positive thallium-201 SPECT.

The aim of this research is to develop biocompatible nanofibrous mats using hydroxyethyl cellulose with improved cellular adhesion profiles and stability and use these fibrous mats as potential scaffold for skin tissue engineering. Glutaraldehyde was used to treat the scaffolds water insoluble as well as improve their biostability for possible use in biomedical applications. Electrospinning of hydroxyethyl cellulose (5 wt%) with poly(vinyl alcohol) (15 wt%) incorporated with and without collagen was blended at (1:1:1) and (1:1) ratios, respectively, and was evaluated for optimal criteria as tissue engineering scaffolds. The nanofibrous mats were crosslinked and characterized by scanning electron microscope, Fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Scanning electron microscope images showed that the mean diameters of blend nanofibers were gradually increased after chemically crosslinking with glutaraldehyde. Fourier transform infrared spectroscopy was carried out to understand chemical interactions in the presence of aldehyde groups. Thermal characterization results showed that the stability of hydroxyethyl cellulose/poly(vinyl alcohol) and hydroxyethyl cellulose/poly(vinyl alcohol)/collagen nanofibers was increased with glutaraldehyde treatment. Studies on cell-scaffolds interaction were carried out by culturing human fibroblast (hFOB) cells on the nanofibers by assessing the growth, proliferation, and morphologies of cells. The scanning electron microscope results show that better cell proliferation and attachment appeared on hydroxyethyl cellulose/poly(vinyl alcohol)/collagen substrates after 7 days of culturing, thus, promoting the potential of electrospun scaffolds as a promising candidate for tissue engineering applications., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

A homologous series of polyhydroxylated poly(p-phenylene)s with different alkoxy groups (C6PPPOH, C12PPPOH, and C18PPPOH) were synthesized with use of the Suzuki polycondensation reaction. Comparative studies of the structure correlation between their photophysical properties and film morphology is described. The absorption and emission spectra of polymers in solution and thin films showed similar features indicating that the electronic properties in solution were retained in the film state. Compared to the polymer with the short alkoxy chains (C6PPPOH), the polymers with long alkoxy groups (C12PPPOH and C18PPPOH) showed improved film forming properties with continuous and smooth film morphology. The absorption properties of the C12PPPOH showed an enhanced effective conjugation length and high quantum yield implying planarization of the backbone through alkoxy chain packing (C12H25O-) and potential hydrogen bonds. No overlap in the absorption and emission spectra was observed, which indicated minimized excimer formation or excitation energy transfer in the films. Time-resolved fluorescence measurements showed that the decay times increased from 43 ps (C6PPPOH) to 78 ps (C12PPPOH) and 99 ps (C18PPPOH). Electrochemical studies were performed for all polymers and the observed oxidation potential for C6PPPOH was higher than that of C12PPPOH and C18PPPOH. In addition, the C12PPPOH has the lowest band gap of DeltaE = 2.59 eV when compared to the 3.1 (C6PPPOH) and 2.61 eV (C18PPPOH) gaps. The optical band gaps estimated from the absorption onset of the polymers are significantly higher than those obtained from electrochemical data. C12PPPOH was chosen for investigating the charge carrier mobility by the time-of-flight (TOF) technique. The observed results also showed negative field dependent values of the drift mobility for the polymer C12PPPOH.

The methyltransferase component of type I DNA restriction and modification systems comprises three subunits, one DNA sequence specificity subunit and two DNA modification subunits. Limited proteolysis of the EcoKI methyltransferase shows that a 55-kDa N-terminal fragment of the 59-kDa modification subunit is resistant to degradation. We have purified this fragment and determined by mass spectrometry that proteolysis removes 43 or 44 amino acids from the C-terminus. The fragment fails to interact with the other subunits even though it still possesses secondary and tertiary structure and the ability to bind the S-adenosylmethionine cofactor. We conclude that the C-terminal region of the modification subunit of EcoKI is essential for the assembly of the EcoKI methyltransferase.

The assembly of atherogenic lipoproteins requires the formation in the endoplasmic reticulum of a complex between apolipoprotein (apo)B, a microsomal triglyceride transfer protein (MTP) and protein disulphide isomerase (PDI). Here we show by molecular modelling and mutagenesis that the globular amino-terminal regions of apoB and MTP are closely related in structure to the ancient egg yolk storage protein, vitellogenin (VTG). In the MTP complex, conserved structural motifs that form the reciprocal homodimerization interfaces in VTG are re-utilized by MTP to form a stable heterodimer with PDI, which anchors MTP at the site of apoB translocation, and to associate with apoB and initiate lipid transfer. The structural and functional evolution of the VTGs provides a unifying scheme for the invertebrate origins of the major vertebrate lipid transport system., (Copyright 1999 Academic Press.)