Postgraduate training for trauma prevention, injury surveillance and research, Uganda.

PROBLEM: The burden of trauma and injuries in Uganda is substantial and growing. Two important gaps that need addressing are the shortage of trained people and a lack of national data on noncommunicable diseases and their risk factors in Uganda. APPROACH: We developed and implemented a new track within an existing master of public health programme, aimed at developing graduate-level capacity and promoting research on key national priorities for trauma and injuries. We also offered training opportunities to a wider audience and set up a high-level national injury forum to foster national dialogue on addressing the burden of trauma, injuries and disability. LOCAL SETTING: The Chronic Consequences of Trauma, Injuries and Disability in Uganda programme was implemented in 2012 at Makerere University School of Public Health in Kampala, Uganda, in conjunction with Johns Hopkins Bloomberg School of Public Health in Baltimore, United States of America. RELEVANT CHANGES: Over the years 2012 to 2017 we supported four cohorts of master's students, with a total of 14 students (9 females and 5 males; mean age 30 years). Over 1300 individuals participated in workshops and seminars of the short-term training component of the programme. The forum hosted three research symposia and two national injury forums. LESSONS LEARNT: Institutional support and collaborative engagement is important for developing and implementing successful capacity development programmes. Integration of training components within existing academic structures is key to sustainability. Appropriate mentorship for highly motivated and talented students is valuable for guiding students through the programme.

Bacterial viability in dry-surface biofilms in healthcare facilities: a systematic review.

BACKGROUND: Bacteria are known to live inside architectural structures called biofilms. Though standard biofilms have been studied extensively for more than 50 years, little is known about dry-surface biofilms (DSBs). Since 2012, DSBs have been described in several scientific papers, but basic knowledge about the viability and culturability of bacteria remains limited. AIM: To conduct a systematic review to determine whether bacteria inside DSBs are viable, culturable, and enumerable. METHODS: Eligible articles had to deal with DSBs containing at least one bacterial species involved in healthcare-associated infections, which developed in actual healthcare environments (in-situ) or with the help of any biofilm model (in-vitro). FINDINGS: Twenty-four articles were included in the review. Whereas most of them isolated viable bacteria (87% in situ; 100% in vitro), no in-situ study quantified culturable bacteria in the biofilm per unit area. Conversely, 100% of in-vitro studies cultured the bacteria from controls and 94.4% supplied an enumeration of them. Culturable bacteria also grew after 78% of the cleaning, disinfection, or sterilization protocols tested. Microscopic observations after staining the samples with live/dead fluorescent probes (Baclight®) showed large amounts of viable cells in culture-negative samples. CONCLUSION: Our study questions the efficacy of current methods for microbiological monitoring of surfaces, since these methods are only based on bacterial culturability. To improve both surface monitoring and cleaning and disinfection protocols, it is necessary to integrate the concept of DSBs which appears to contain a significant amount of viable but non-culturable bacteria.

Outbreak of leptospirosis among canyoning participants, Martinique, 2011.

Two gendarmes who participated in canyoning activities on 27 June 2011 on the Caribbean island of Martinique were diagnosed with leptospirosis using quantitative real-time polymerase chain reaction (qPCR), 9 and 12 days after the event. Among the 45 participants who were contacted, 41 returned a completed questionnaire, of whom eight met the outbreak case definition. The eight cases sought medical attention and were given antibiotics within the first week after fever onset. No severe manifestations of leptospirosis were reported. In seven of the eight cases, the infection was confirmed by qPCR. Three pathogenic Leptospira species, including L. kmetyi, were identified in four of the cases. None of the evaluated risk factors were statistically associated with having developed leptospirosis. Rapid diagnostic assays, such as qPCR, are particularly appropriate in this setting ­ sporting events with prolonged fresh-water exposure ­ for early diagnosis and to help formulate public health recommendations. Participants in such events should be made specifically aware of the risk of leptospirosis, particularly during periods of heavy rainfall and flooding.

Global Neurotrauma Surveillance: Are National Databases Overrated? Comment on "Neurotrauma Surveillance in National Registries of Low- and Middle-Income Countries: A Scoping Review and Comparative Analysis of Data Dictionaries".

Injuries are a public health crisis. Neurotrauma, a specific type of injury, is a leading cause of death and disability globally, with the largest burden in low- and middle-income countries (LMICs). However, there is a lack of quality neurotrauma-specific data in LMICs, especially at the national level. Without standard criteria for what constitutes a national registry, and significant challenges frequently preventing this level of data collection, we argue that single-institution or regional databases can provide significant value for context-appropriate solutions. Although granular data for larger populations and a universal minimum dataset to enable comparison remain the gold standard, we must put progress over perfection. It is critical to engage local experts to explore available data and build effective information systems to inform solutions and serve as the foundation for quality and process improvement initiatives. Other items to consider include adequate resource allocation and leveraging of technology as we work to address the persistent but largely preventable injury pandemic.

Mobile Subcutaneous Calcinosis Cutis: A Case Report of a Mobile Solitary Subepidermal Calcified Nodule on a Woman's Leg and a Review of Mobile Subcutaneous Tumors.

Calcinosis cutis describes the deposition of calcium in the dermis. A case of a 69-year-old woman with idiopathic calcinosis cutis that presented as a mobile subcutaneous nodule is described. The patient had an asymptomatic, firm, mobile subcutaneous nodule on her right lower leg of at least six months duration. The nodule could be easily moved from one location to another. An incisional biopsy was performed. Microscopic examination of the tissue specimen showed islands of basophilic calcium material in dense sclerotic dermal connective tissue establishing the diagnosis of calcinosis cutis. Mobile solitary calcification is an unusual presentation of idiopathic calcinosis cutis. In addition to idiopathic calcinosis cutis, benign mobile subcutaneous tumors have also been derived from adnexal structures of hair follicles and adipose tissue. Hence, not only idiopathic calcinosis cutis, but also subepidermal calcinosis in the ocular adnexa, proliferating trichilemmal cyst with focal calcification, and mobile encapsulated adipose tissue can present as a mobile subcutaneous nodule. The features of idiopathic calcinosis presenting as a mobile subcutaneous nodule as well as the characteristics of other benign mobile subcutaneous tumors are reviewed.

Competition between skin antimicrobial peptides and commensal bacteria in type 2 inflammation enables survival of S. aureus.

During inflammation, the skin deploys antimicrobial peptides (AMPs) yet during allergic inflammation it becomes more susceptible to Staphylococcus aureus. To understand this contradiction, single-cell sequencing of Il4ra-/- mice combined with skin microbiome analysis reveals that lower production of AMPs from interleukin-4 receptor α (IL-4Rα) activation selectively inhibits survival of antibiotic-producing strains of coagulase-negative Staphylococcus (CoNS). Diminished AMPs under conditions of T helper type 2 (Th2) inflammation enable expansion of CoNS strains without antibiotic activity and increase Staphylococcus aureus (S. aureus), recapitulating the microbiome on humans with atopic dermatitis. This response is rescued in Camp-/- mice or after topical steroids, since further inhibition of AMPs enables survival of antibiotic-producing CoNS strains. In conditions of Th17 inflammation, a higher expression of host AMPs is sufficient to directly inhibit S. aureus survival. These results show that antimicrobials produced by the host and commensal bacteria each act to control S. aureus on the skin.

Analysis of Cutaneous Lupus Hospitalizations: A United States National Population-Based Study.

Background There are limited studies analyzing cutaneous lupus erythematosus (CLE) hospitalizations. In this study, we aimed to analyze baseline demographics of systemic lupus erythematosus (SLE) and CLE patients, identify the most common reasons for hospitalizations, and find out the hospitalization outcomes.  Materials and methods We performed the analysis using the National (Nationwide) Inpatient Sample (NIS) database between 2016 and 2019. For the CLE cohort, data for adults aged 18 years and older with the primary or secondary diagnosis of CLE using International Classification of Disease - 10th revision (ICD-10) codes were extracted. For comparison, the SLE cohort was identified by patients aged 18 years and older with primary or secondary diagnoses of SLE using ICD-10 codes. Chi-squared test was used to compare baseline demographic characteristics. Multivariable logistic and linear regression was used to calculate outcomes of interest. Results In comparison to the SLE cohort, the CLE cohort was not only older in age and lower percentage female, but also had shorter length of stay, less total hospital charge, and the majority had Medicare as primary insurance. The SLE cohort included predominantly African American patients while the CLE cohort was majority Caucasian patients. The cardiovascular risks were more prevalent in the CLE cohort and most commonly admitted for sepsis, cardiovascular disease, and mental health disorders. Conclusion Our study highlights the importance of outpatient follow-up in CLE patients to closely monitor cardiovascular risk factors, early identification of infections, and routine mental health screenings to reduce hospitalizations and resource utilization.

Molecular characterization of Staphylococcus aureus from outpatients in the Caribbean reveals the presence of pandemic clones.

Staphylococcus aureus infections continue to pose a global public health problem. Frequently, this epidemic is driven by the successful spread of single S. aureus clones within a geographic region, but international travel has been recognized as a potential risk factor for S. aureus infections. To study the molecular epidemiology of S. aureus infections in the Caribbean, a major international tourist destination, we collected methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates from community-onset infections in the Dominican Republic (n = 112) and Martinique (n = 143). Isolates were characterized by a combination of pulsed-field gel electrophoresis (PFGE), spa typing, and multilocus sequence typing (MLST) typing. In Martinique, MRSA infections (n = 56) were mainly caused by t304-ST8 strains (n = 44), whereas MSSA isolates were derived from genetically diverse backgrounds. Among MRSA strains (n = 22) from the Dominican Republic, ST5, ST30, and ST72 predominated, while ST30 t665-PVL+ (30/90) accounted for a substantial number of MSSA infections. Despite epidemiological differences in sample collections from both countries, a considerable number of MSSA infections (~10%) were caused by ST5 and ST398 isolates at each site. Further phylogenetic analysis suggests the presence of lineages shared by the two countries, followed by recent genetic diversification unique to each site. Our findings also imply the frequent import and exchange of international S. aureus strains in the Caribbean.

Disparities in Access to Trauma Care in Sub-Saharan Africa: a Narrative Review.

Purpose of Review: Sub-Saharan Africa is a diverse context with a large burden of injury and trauma-related deaths. Relative to high-income contexts, most of the region is less mature in prehospital and facility-based trauma care, education and training, and trauma care quality assurance. The 2030 Agenda for Sustainable Development recognizes rising inequalities, both within and between countries as a deterrent to growth and development. While disparities in access to trauma care between the region and HICs are more commonly described, internal disparities are equally concerning. We performed a narrative review of internal disparities in trauma care access using a previously described conceptual model. Recent Findings: A broad PubMed and EMBASE search from 2010 to 2021 restricted to 48 sub-Saharan African countries was performed. Records focused on disparities in access to trauma care were identified and mapped to de Jager's four component framework. Search findings, input from contextual experts, comparisons based on other related research, and disaggregation of data helped inform the narrative. Only 21 studies were identified by formal search, with most focused on urban versus rural disparities in geographical access to trauma care. An additional 6 records were identified through citation searches and experts. Disparity in access to trauma care providers, detection of indications for trauma surgery, progression to trauma surgery, and quality care provision were thematically analyzed. No specific data on disparities in access to injury care for all four domains was available for more than half of the countries. From available data, socioeconomic status, geographical location, insurance, gender, and age were recognized disparity domains. South Africa has the most mature trauma systems. Across the region, high quality trauma care access is skewed towards the urban, insured, higher socioeconomic class adult. District hospitals are more poorly equipped and manned, and dedicated trauma centers, blood banks, and intensive care facilities are largely located within cities and in southern Africa. The largest geographical gaps in trauma care are presumably in central Africa, francophone West Africa, and conflict regions of East Africa. Disparities in trauma training opportunities, public-private disparities in provider availability, injury care provider migration, and several other factors contribute to this inequity. National trauma registries will play a role in internal inequity monitoring, and deliberate development implementation of National Surgical, Obstetrics, and Anesthesia plans will help address disparities. Human, systemic, and historical factors supporting these disparities including implicit and explicit bias must be clearly identified and addressed. Systems approaches, strategic trauma policy frameworks, and global and regional coalitions, as modelled by the Global Alliance for Care of the Injured and the Bellagio group, are key. Inequity in access can be reduced by prehospital initiatives, as used in Ghana, and community-based insurance, as modelled by Rwanda. Summary: Sub-Saharan African countries have underdeveloped trauma systems. Consistent in the narrative is the rural-urban disparity in trauma care access and the disadvantage of the poor. Further research is needed in view of data disparity. Recognition of these disparities should drive creative equitable solutions and focused interventions, partnerships, accompaniment, and action. Supplementary Information: The online version contains supplementary material available at 10.1007/s40719-022-00229-1.

Reliability and validity of COOP/WONCA functional health status charts for stroke patients in primary care.

Dartmouth Coop Functional Health Assessment/World Organization of National Colleges, Academies and Academic Association of General Practitioners (COOP/WONCA) functional health assessment charts depict levels of function/well being along 5-point ordinal scales in 6 domains. Responses, illustrated by drawings, make these charts a suitable tool for the stroke population, given the high prevalence (20%) of language impairment in this population. This study examined the validity and reliability of COOP/WONCA charts for community-dwelling stroke survivors. A total of 55 participants in this cross-sectional study completed COOP/WONCA Charts, Hospital Anxiety and Depression Scale (HAD), Stroke Specific Quality of Life Scale (SSQoL), EuroQoL EQ-5D and visual analogue scale (VAS), International Physical Activity Questionnaire (IPAQ), and Astrand-Rhyming submaximal oxygen volume (VO2) fitness test. Spearman's correlation coefficient was used to test criterion validity, Cronbach's α was used to test internal validity, and the Mann-Whitney U tested discriminative validity. A subgroup (n = 30) completed COOP/WONCA charts 2 days later, and test-retest reliability (Kendall's τ-b statistic) analysis was conducted. Good agreement was observed between COOP/WONCA physical fitness chart, VO2, and IPAQ (ρ = -0.438, P = .001; ρ = -0.497, P < .001), COOP/WONCA feelings chart and HAD anxiety and depression scores (ρ = 0.498, P < .001; ρ = 0.494, P < .001), COOP/WONCA overall health chart and EuroQol EQ-5D VAS (ρ = -0.535; P < .001), and COOP/WONCA daily activity and social activity charts and SSQoL (ρ = -0.371, P = .005; ρ = -0.463, P < .001). Cronbach's α (0.72) reflected good internal consistency among COOP/WONCA scales. Discriminative ability for independent ambulation and clinical depression was demonstrated (U = 103.5, P < .001; U = 156, P = .015). Test-retest reliability in each domain except Changes in Health was significant at P < .05 (Kendall's τ-b, 0.344-0.653). Our data indicate that the COOP/WONCA Functional Health charts demonstrate good validity and overall reliability for use with stroke patients in primary care.

An Unexpected Case of Malignant Mesothelioma in a Young Woman.

A 41-year-old female with a past medical history significant only for right retinal vein occlusion presented with chest pain, cough, and shortness of breath. After being found to have a large right-sided pleural effusion and undergoing a nondiagnostic thoracentesis, a noncontrast chest computed tomography scan revealed multiple diffuse nodules in the right lung with irregular paraspinal pleural thickening. An extensive workup followed, with computed tomography-guided biopsy ultimately revealing the diagnosis. The following report describes the patient presentation, laboratory findings, and extensive clinical investigation, and provides a discussion of the epidemiology, imaging findings, prognosis, and differential diagnoses for the illness in question.

Assessment of 34 dissolved and particulate organic and metallic micropollutants discharged at the outlet of two contrasted urban catchments.

The assessment of micropollutants in urban wet weather discharges is essential to improve the knowledge of the impact of such discharges on receiving waters. This study assessed the quality of combined sewer overflows (CSOs) in Ecully (residential catchment) and stormwater runoff in Chassieu (industrial catchment) during rain events by providing data on occurrence and total event mean concentrations (EMCt) of 34 priority substances (PS) (9 metals, 13 pesticides, 6 PAHs, 4 alkylphenols and 2 chlorobenzenes) in dissolved and particulate fractions. Over 34 substances monitored, 23 were quantified in urban wet weather discharges of both catchments. For both catchments, 9 metals and 6 PAHs monitored were always quantified, reflecting their ubiquitous presence. For other organic pollutants, only 5 pesticides were quantified and only 2 alkyphenols were measured solely in dissolved fraction. A significant site-to-site difference was observed for metals, PAHs and alkylphenols. The highest concentrations were measured in stormwater runoff in Chassieu vs. Ecully. On the contrary, the diuron concentrations were highest in CSO discharges in Ecully. Distribution of the PS between particulate and dissolved fractions provides information for urban stormwater practitioners. Most PS in urban wet weather discharges were mainly linked to particles (PAHs, Pb, Ti for example). The comparison between daily flows of wastewater treatment plants during dry weather and CSOs daily flows in Ecully showed that stormwater was the most important source of contamination for fluoranthene, benzo(b)fluoranthene and benzo(k)fluoranthene and 7 metals (As, Cr, Co, Cu, Pb, Ti and Zn) in receiving water bodies, but not for pesticides and alkylphenols.

Road traffic injuries in Uganda: pre-hospital care time intervals from crash scene to hospital and related factors by the Uganda Police.

A cross-sectional survey was conducted to collect primary data prospectively on pre-hospital care time intervals of Road Traffic Crash (RTC) victims that had been rescued by the Uganda police and to determine what factors were related to those intervals. The survey was conducted between 1 May 2015 and 31 May 2015. The Police responses to 96 RTCs were recorded, but only 74 of them were considered serious enough to warrant hospital transfer, and those 74 are the subject of the analysis. Pre-hospital care time ranged between 10 and 220 min. Seventy-two per cent of the calls were completed within 1 h of call initiation. The scene to hospital transport interval was the longest with a mean of 19.07 min (SD 10.11). Activation time was the shortest interval with a mean of 4.58 min (SD 5.67). Key factors for delays included: understaffing, lack of skills and long distances. A toll-free Universal Access Number, a law mandating provision of free basic emergency medical services at every health facility and gazetting of lanes for emergency services and might decrease on pre-hospital care time and could reduce on the notification and transport time interval respectively.

Towards the development of a broadly protective group a streptococcal vaccine based on the Lipid-Core Peptide system.

Preclinical studies carried out over the last seven years by our group have focused on the development of a group A streptococcal (GAS) vaccine based on the antiphagocytic bacterial surface M protein using the Lipid-Core Peptide (LCP) system. This synthetic peptide vaccine delivery system has several advantages over other delivery systems including its self-adjuvanting properties and the ability to incorporate multiple peptide epitopes into a single vaccine. This review describes various vaccine delivery strategies including the LCP system, highlighting its functional properties and applications in vaccine research using data obtained from various LCP-based GAS vaccine candidates evaluated in murine models.

The impact of traumatic brain injuries: a global perspective.

Traumatic brain injury (TBI), according to the World Health Organization, will surpass many diseases as the major cause of death and disability by the year 2020. With an estimated 10 million people affected annually by TBI, the burden of mortality and morbidity that this condition imposes on society, makes TBI a pressing public health and medical problem. The burden of TBI is manifest throughout the world, and is especially prominent in Low and Middle Income Countries which face a higher preponderance of risk factors for causes of TBI and have inadequately prepared health systems to address the associated health outcomes. Latin America and Sub Saharan Africa demonstrate a higher TBI-related incidence rate varying from 150-170 per 100,000 respectively due to RTIs compared to a global rate of 106 per 100,000. As highlighted in this global review of TBI, there is a large gap in data on incidence, risk factors, sequelae, financial costs, and social impact of TBI. This should be addressed through planning of comprehensive TBI prevention programs in LMICs through well-established surveillance systems. Greater resources for research and prioritized interventions are critical to promote evidence-based policy for TBI.

Activation of carcinogenic arylhydroxamic acids by human tissues.

Incubation of the carcinogenic arylhydroxamic acids N-hydroxy-N-2-fluorenylacetamide or N-hydroxy-N-4-biphenylacetamide and tRNA with 105,000 times g supernatants of homogenates of human small intestine, liver, or colon led to formation of arylamine-substituted nucleic acid adducts. These data indicated that enzymes of human tissues could activate arylhydroxamic acids by N leads to O acyl transfer. The unstable N-acetoxyarylamines formed by these enzymes reacted spontaneously with the tRNA to give covalently linked adducts with the nucleic acid.

Comparative effects of strain, species, and sex on the acyltransferase- and sulfotransferase-catalyzed activations of N-hydroxy-N-2-fluorenylacetamide.

The arylhydroxamic acid acyltransferase, an enzyme that promotes the introduction of arylamine groups into nucleic acids, is greater in the stomach, small intestine, colon, and lung of the Sprague-Dawley rat than in comparable tissues of Fischer animals. The enzyme is distributed relatively evenly from the glandular stomach to the distal portion of the colon. No consistent differences in acyltransferase activities of the liver, kidney, brain, or spleen of these two strains were noted. Acyltransferase activity was readily demonstrable in the livers of guinea pigs, hamsters, rabbits, and monkeys; in the kidneys of guinea pigs and hamsters; in the stomachs of guinea pigs and hamsters; in the small intestines of guinea pigs, hamsters, rabbits, and monkeys; in the colons of guinea pigs and hamsters; and in lungs of hamsters. Mouse, dog, and goat tissues were essentia-ly devoid of acyltransferase activity. The transformation of N-hydroxy-N-2-fluorenylacetamide into a reactive species by conjugation with sulfate was carried out with 105,000 times g supernatants of liver from Sprague-Dawley and Fischer rats and their Flhydrids. The abilities of liver extracts from the hybrids to carry out this activation were intermediate between those from animals of the same sex of the two parental strains.

Upregulation of Haploinsufficient Gene Expression in the Brain by Targeting a Long Non-coding RNA Improves Seizure Phenotype in a Model of Dravet Syndrome.

Dravet syndrome is a devastating genetic brain disorder caused by heterozygous loss-of-function mutation in the voltage-gated sodium channel gene SCN1A. There are currently no treatments, but the upregulation of SCN1A healthy allele represents an appealing therapeutic strategy. In this study we identified a novel, evolutionary conserved mechanism controlling the expression of SCN1A that is mediated by an antisense non-coding RNA (SCN1ANAT). Using oligonucleotide-based compounds (AntagoNATs) targeting SCN1ANAT we were able to induce specific upregulation of SCN1A both in vitro and in vivo, in the brain of Dravet knock-in mouse model and a non-human primate. AntagoNAT-mediated upregulation of Scn1a in postnatal Dravet mice led to significant improvements in seizure phenotype and excitability of hippocampal interneurons. These results further elucidate the pathophysiology of Dravet syndrome and outline a possible new approach for the treatment of this and other genetic disorders with similar etiology.

Glutathione S-conjugate transport by cultured human cells.

Elimination of the products of xenobiotic metabolism is an important step in cellular detoxification and involves a specific transport system or "export pump". ATP-dependent transport of glutathione S-conjugates has previously been demonstrated in a variety of tissues, mainly from rat. However, the characteristics of this pump have not been fully explored in human cells. This study investigated transport of a glutathione S-conjugate, 2,4-dinitrophenyl glutathione (GS-DNP), by a variety of cultured human cell lines. GS-DNP was generated intracellularly after treatment of cells with 1-chloro-2,4-dinitrobenzene and subsequent transport of the conjugate into the extracellular medium was measured spectrophotometrically at 340 nm. Calculation of the initial transport rates at 37 degrees C revealed considerable variation in GS-DNP secretion between cell lines which was statistically significant in some cases. A 2-fold increase in GS-DNP efflux was observed between Jurkat and HL-60 cells (11.360 +/- 3.893 vs. 5.662 +/- 2.263 nmol/10(6) cells/h, P < 0.007). The highest rate of transport was found in HepG2 cells (14.171 +/- 4.790 nmol/10(6) cells/h) whereas the 5637 cell line had the lowest level with a transport rate of 1.475 +/- 0.631 nmol/10(6) cells/h. For each cell line, transport of GS-DNP was almost totally inhibited or markedly reduced on ice. Pre-incubation of cells at 42 degrees C also lowered the initial transport rates compared with cells maintained at 37 degrees C but these were not significantly different except in the case of HeLa cells. ATP levels ranged from 30.5 to 89.3 nmol/mg protein and there was variation in the glutathione content and glutathione S-transferase activities of the cells. This report demonstrates firstly that transport of glutathione conjugates is a feature of many cell types in vitro and secondly that the basal levels of GS-DNP secretion vary significantly between human cells.

A serum-free culture method for myeloma progenitors in vitro: proliferative and immunophenotypic characteristics.

Methods for forming multiple myeloma (MM) colonies are difficult because nonproliferative, but viable, plasma cells can survive for several weeks in culture and because MM cells tend to clump readily, forming pseudo-colonies. The present study describes a method for growing pure myeloma colonies in serum-free conditions in which genuine myeloma growth is unequivocally demonstrated. Growth was observed in 17 of 32 MM bone marrow samples. After a delay of 3-5 weeks, during which most cells died, Ig light-chain-restricted colonies emerged, expanded for approximately 3 weeks, and then showed no evidence of further proliferation. Cell doubling time was 8-10 days, and a significant number of cells in all cultures expressed Ki-67, having earlier lacked this nuclear proliferation antigen. In addition, colony formation was abrogated by irradiation, and two of eight cultures were successfully replated in 0.8% methylcellulose. Phenotypic analysis revealed a mixed population of plasma cells (RFD6+) and B-lymphocytes (CD19+, CAL-LA-), and cells were consistently Epstein-Barr virus negative. Culture of myeloma bone marrow by this serum-free method will allow appraisal of the role of various recombinant growth factors.