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Stem cell therapies have shown promise for regenerative treatment for musculoskeletal conditions, but their success is mixed. To enhance regenerative effects, growth factors are utilized to induce differentiation into native cell types, but uncontrollable in vivo conditions inhibit differentiation, and precise control of expressed matrix proteins is difficult to achieve. To address these issues, we investigated a novel method of enhancing regenerative phenotype through direct upregulation of major cartilaginous tissue proteins, aggrecan (ACAN), and collagen II (COL2A1) using dCas9-VPR CRISPR gene activation systems. We demonstrated increased expression and deposition of targeted proteins independent of exogenous growth factors in pellet culture. Singular upregulation of COL2A1/ACAN interestingly indicates that COL2A1 upregulation mediates the highest sulfated glycosaminoglycan (sGAG) deposition, in addition to collagen II deposition. Through RNA-seq analysis, this was shown to occur by COL2A1 upregulation mediating broader chondrogenic gene expression changes. Multiplex upregulation of COL2A1 and ACAN together resulted in the highest sGAG, and collagen II deposition, with levels comparable to those in chondrogenic growth factor-differentiated pellets. Overall, this work indicates dCas9-VPR systems can robustly upregulate COL2A1 and ACAN deposition without growth factors, to provide a novel, precise method of controlling stem cell phenotype for cartilage and intervertebral disc cell therapies and tissue engineering. IMPACT STATEMENT: Stem cell therapies have come about as a potential regenerative treatment for musculoskeletal disease, but clinically, they have mixed results. To improve stem cell therapies, growth factors are used to aid a regenerative cell phenotype, but their effects are inhibited by in vivo musculoskeletal disease environments. This article describes CRISPR gene activation-based cell engineering methods that provide a growth factor-free method of inducing chondrogenic extracellular matrix deposition. This method is demonstrated to be as/more potent as growth factors in inducing a chondrogenic phenotype in pellet culture, indicating potential utility as a method of enhancing stem cell therapies for musculoskeletal disease.

Low back pain is among the leading causes of disability worldwide. The degenerative intervertebral disc (IVD) environment contains pathologically high levels of inflammatory cytokines and acidic pH hypothesized to contribute to back pain by sensitizing nociceptive neurons to stimuli that would not be painful in healthy patients. We hypothesized that the degenerative IVD environment drives discogenic pain by sensitizing nociceptive neurons to mechanical loading. To test this hypothesis, we developed an in vitro model that facilitated the investigation of interactions between the degenerative IVD environment, nociceptive neurons innervating the IVD and mechanical loading of the disc; and, the identification of the underlying mechanism of degenerative IVD induced nociceptive neuron sensitization. In our model, rat dorsal root ganglia (DRG) neurons were seeding onto bovine annulus fibrosus tissue, exposed to degenerative IVD conditioned media and/or acidic pH, and subjected to cyclic tensile strain (1 Hz; 1%-6% strain) during measurement of DRG sensory neuron activity via calcium imaging. Using this model, we demonstrated that both degenerative IVD conditioned media and degenerative IVD acidic pH levels induced elevated nociceptive neuron activation in response to physiologic levels of mechanical strain. In addition, interleukin 6 (IL-6) was demonstrated to mediate degenerative IVD conditioned media induced elevated nociceptive neuron activation. These results demonstrate IL-6 mediates degenerative IVD induced neuron sensitization to mechanical loading and further establishes IL-6 as a potential therapeutic target for the treatment of discogenic pain. Data further suggests the degenerative IVD environment contains multiple neuron sensitization pathways (IL-6, pH) that may contribute to discogenic pain.

Back pain is the leading cause of disability worldwide and contributes to significant socioeconomic impacts. It has been hypothesized that the degenerative intervertebral disc (IVD) contributes to back pain by sensitizing nociceptive neurons innervating the IVD to stimuli that would not be painful to healthy patients. However, the inflammatory signaling networks mediating this sensitization remain poorly understood. A better understanding of the underlying mechanisms of degenerative IVD-induced changes in nociception is required to improve the understanding and treatment of back pain. Toward these ends, a novel in vitro model was developed to investigate degenerative IVD-induced changes in dorsal root ganglion (DRG) neuron activation by measuring DRG neuron activity following neuron seeding on human degenerative IVD tissue collected from patients undergoing surgical treatment for back pain. Lentiviral clustered regularly interspaced palindromic repeat (CRISPR) epigenome editing vectors were built to downregulate the inflammatory receptors TNFR1, IL1R1, and IL6st in DRG neurons in single- and multiplex. Multiplex CRISPR epigenome editing of inflammatory receptors demonstrated that degenerative IVD tissue drives thermal sensitization through the simultaneous and redundant signaling of interleukin (IL)-6, tumor necrosis factor alpha (TNF-α), and IL-1β. This work elucidates redundant signaling pathways in neuron interactions with the degenerative IVD and suggests the need for multiplex targeting of IL-6, TNF-α, and IL-1β for pain modulation in the degenerative IVD.

The aim of the study was to assess the contemporary presentation and management of subglottic cysts and make recommendations on the treatment of these patients.Retrospective case series of 105 patients between October 1999 and November 2017 from a paediatric teaching hospital.Ninety-one percentage (n = 96) had a history of prematurity, with a mean gestation of 27.2 weeks (SD ± 4.1). A history of intubation was found in 99% (n = 104) of cases [median 18 days (range = 1-176)]. Presenting symptoms were: Stridor 57.1%, (n = 60), difficult intubation 14% (n = 15), recurrent croup 11.4% (n = 12), failed extubation 7.6%, (n = 8), hoarseness/weak cry 10.5% (n = 10). Ninety percentage (n = 94) underwent intervention for management of SGCs with 86% (n = 81) treated with cold steel marsupialisation and 14% (n = 13) with CO SGC are an uncommon, reversible cause of upper airway obstruction and should be considered in the list of differential diagnoses in patients with a history of prematurity and perinatal intubation, presenting with stridor. While concurrent SGS is common, adequate symptom improvement in such cases may be achieved with SGC removal alone. Management is by surgical marsupialisation. Recurrence and additional airway pathologies are common and may necessitate longer-term treatment in centres with paediatric airway expertise.

The intervertebral disc contributes to motion, weight bearing, and flexibility of the spine, but is susceptible to damage and morphological changes that contribute to pathology with age and injury. Engineering strategies that rely upon synthetic materials or composite implants that do not interface with the biological components of the disc have not met with widespread use or desirable outcomes in the treatment of intervertebral disc pathology. Here we review bioengineering advances to treat disc disorders, using cell-supplemented materials, or acellular, biologically based materials, that provide opportunity for cell-material interactions and remodeling in the treatment of intervertebral disc disorders. While a field still in early development, bioengineering-based strategies employing novel biomaterials are emerging as promising alternatives for clinical treatment of intervertebral disc disorders.

Cell therapies are an up and coming technology in orthopedic medicine that has the potential to provide regenerative treatments for musculoskeletal disease. Despite numerous cell therapies showing preclinical success for common musculoskeletal indications of disc degeneration and osteoarthritis, there have been mixed results when testing these therapies in humans during clinical trials. A theory behind the mixed success of these cell therapies is that the harsh microenvironments of the disc and knee they are entering inhibit their anabolism and survival. Therefore, there is much ongoing research looking into how to improve the survival and anabolism of cell therapies within these musculoskeletal disease environments. This includes research into improving cell function under specific microenvironmental conditions known to exist in the intervertebral disc (IVD) and knee environment such as hypoxia, low-nutrient conditions, hyperosmolarity, acidity, and inflammation. This research also includes improving differentiation of cells into desired native cell phenotypes to better enhance their survival and anabolism in the knee and IVD. This review highlights the effects of specific musculoskeletal microenvironmental challenges on cell therapies and what research is being done to overcome these challenges. Impact statement While there has been significant clinical interest in using cell therapies for musculoskeletal pathologies in the knee and intervertebral disc, cell therapy clinical trials have had mixed outcomes. The information presented in this review includes the environmental challenges (i.e., acidic pH, inflammation, hyperosmolarity, hypoxia, and low nutrition) that cell therapies experience in these pathological musculoskeletal environments. This review summarizes studies that describe various approaches to improving the therapeutic capability of cell therapies in these harsh environments. The result is an overview of what approaches can be targeted and/or combined to develop a more consistent cell therapy for musculoskeletal pathologies.

Degenerative disc disease (DDD) is a primary contributor to low-back pain, a leading cause of disability. Progression of DDD is aided by inflammatory cytokines in the intervertebral disc (IVD), particularly TNF-α and IL-1β, but current treatments fail to effectively target this mechanism. The objective of this study was to explore the feasibility of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) epigenome editing-based therapy for DDD, by modulation of TNFR1/IL1R1 signaling in pathological human IVD cells. Human IVD cells from the nucleus pulposus of patients receiving surgery for back pain were obtained and the regulation of TNFR1/IL1R1 signaling by a lentiviral CRISPR epigenome editing system was tested. These cells were tested for successful lentiviral transduction/expression of deactivated Cas9 fused to Kruppel Associated Box system and regulation of TNFR1/IL1R1 expression. TNFR1/IL1R1 signaling disruption was investigated through measurement of NF-κB activity, apoptosis, and anabolic/catabolic changes in gene expression postinflammatory challenge. CRISPR epigenome editing systems were effectively introduced into pathological human IVD cells and significantly downregulated TNFR1 and IL1R1. This downregulation significantly attenuated deleterious TNFR1 signaling but not IL1R1 signaling. This is attributed to less robust IL1R1 expression downregulation, and IL-1β-driven reversal of IL1R1 expression downregulation in a portion of patient IVD cells. In addition, RNAseq data indicated novel transcription factor targets, IRF1 and TFAP2C, as being primary regulators of inflammatory signaling in IVD cells. These results demonstrate the feasibility of CRISPR epigenome editing of inflammatory receptors in pathological IVD cells, but highlight a limitation in epigenome targeting of IL1R1. This method has potential application as a novel gene therapy for DDD, to attenuate the deleterious effect of inflammatory cytokines present in the degenerative IVD.

Background The incidence of premature infants with complex medical needs, dependent upon medical technology at discharge, is on the rise in the United States. Purpose Preparing the family for the hospital-to-home transition can be challenging due to the complex medical and emotional needs of the vulnerable infant and the volume of subspecialty services and equipment required. Methods/search strategy Relevant articles from PubMed, Google Scholar, CINAHLFINDINGS/RESULTS:: There is an increasing incidence of technology dependent infants discharged from neonatal intensive care units in the United States. Transition from hospital to home requires lengthy preparation, multidisciplinary-open communication, and family centered care. Implications for practice Early assimilation of the parents into the ongoing care of their infant, the provision of comprehendible parental education by neonatal nurses and other members of the healthcare team, the provision of adequate rooming-in experiences prior to discharge, and the collaborative coordination of outpatient community services are crucial elements of the discharge process. Neonatal nurses possess population-specific education, training, commitment, and expertise that make them the ideal experts to implement and evaluate a discharge planning framework, in collaboration with the medical team and the family. Implications for research Methods to prevent readmission and ensure successful discharge from hospital to home is indicated. Standardization of a discharge process of infants of technology dependence combining medical team, family, outpatient coordinators, and primary care providers.

Musculoskeletal tissues contain critical gradients in extracellular matrix (ECM) composition and cell types that allow for proper mechanical function of tissues and integration between adjacent tissues. However, properly controlling these patterns in engineered tissues is difficult and tissue engineering (TE) is presently in need of methods to generate integration zones for tissue anchoring, transition zones between tissues, and controlled ECM gradients for proper mechanical function. In this study, we present a novel method of using a microfluidic flow cell array (MFCA) to precisely control cell deposition onto TE constructs to produce tunable cell patterns on engineered constructs. In this study, we characterized MFCA cell deposition to efficiently and reliably deposit cells in controllable patterns and densities. We developed methods for deposition of human adipose-derived stem cells and human osteoblasts using a 12-channel pilot printhead. We mimicked key gradients and transitions by creating two-cell and three-cell-type transitions characteristic of the integration zones of musculoskeletal tissues. Overall, we demonstrate the ability to precisely and reproducibly control cell deposition on engineered constructs using this method and control cell population gradients. We establish the production of multicell transitions and multicell interfaces utilizing MFCA cell deposition, to demonstrate the potential of the method to create an extensive variety of engineered musculoskeletal tissues. Furthermore, customization of the printhead design can accommodate various structures, sizes, shapes, and number of flow cell channels to meet specific requirements for a broad range of musculoskeletal tissues.

We developed a new method to manufacture dense, aligned, and porous collagen scaffolds using biaxial plastic compression of type I collagen gels. Using a novel compression apparatus that constricts like an iris diaphragm, low density collagen gels were compressed to yield a permanently densified, highly aligned collagen material. Micro-porosity scaffolds were created using hydrophilic elastomer porogens that can be selectively removed following biaxial compression, with porosity modulated by using different porogen concentrations. The resulting scaffolds exhibit collagen densities that are similar to native connective tissues (∼10% collagen by weight), pronounced collagen alignment across multiple length scales, and an interconnected network of pores, making them highly relevant for use in tissue culture, the study of physiologically relevant cell-matrix interactions, and tissue engineering applications. The scaffolds exhibited highly anisotropic material behavior, with the modulus of the scaffolds in the fiber direction over 100 times greater than the modulus in the transverse direction. Adipose-derived mesenchymal stem cells were seeded onto the biaxially compressed scaffolds with minimal cell death over seven days of culture, along with cell proliferation and migration into the pore spaces. This fabrication method provides new capabilities to manufacture structurally and mechanically relevant cytocompatible scaffolds that will enable more physiologically relevant cell culture studies. Further improvement of manufacturing techniques has the potential to produce engineered scaffolds for direct replacement of dense connective tissues such as meniscus and annulus fibrosus. Statement of Significance In vitro studies of cell-matrix interactions and the engineering of replacement materials for collagenous connective tissues require biocompatible scaffolds that replicate the high collagen density (15–25%/wt), aligned fibrillar organization, and anisotropic mechanical properties of native tissues. However, methods for creating scaffolds with these characteristics are currently lacking. We developed a new apparatus and method to create high density, aligned, and porous collagen scaffolds using a biaxial compression with porogens technique. These scaffolds have a highly directional structure and mechanical properties, with the tensile strength and modulus up to 100 times greater in the direction of alignment. We also demonstrated that the scaffolds are a suitable material for cell culture, promoting cell adhesion, viability, and an aligned cell morphology comparable to the cell morphology observed in native aligned tissues.

Back pain is a major contributor to disability and has significant socioeconomic impacts worldwide. The degenerative intervertebral disc (IVD) has been hypothesized to contribute to back pain, but a better understanding of the interactions between the degenerative IVD and nociceptive neurons innervating the disc and treatment strategies that directly target these interactions is needed to improve our understanding and treatment of back pain. We investigated degenerative IVD-induced changes to dorsal root ganglion (DRG) neuron activity and utilized CRISPR epigenome editing as a neuromodulation strategy. By exposing DRG neurons to degenerative IVD-conditioned media under both normal and pathological IVD pH levels, we demonstrate that degenerative IVDs trigger interleukin (IL)-6-induced increases in neuron activity to thermal stimuli, which is directly mediated by AKAP and enhanced by acidic pH. Utilizing this novel information on AKAP-mediated increases in nociceptive neuron activity, we developed lentiviral CRISPR epigenome editing vectors that modulate endogenous expression of AKAP150 by targeted promoter histone methylation. When delivered to DRG neurons, these epigenome-modifying vectors abolished degenerative IVD-induced DRG-elevated neuron activity while preserving non-pathologic neuron activity. This work elucidates the potential for CRISPR epigenome editing as a targeted gene-based pain neuromodulation strategy.

Hypoxic injury to the developing human brain is a complication of premature birth and is associated with long-term impairments of motor function. Disruptions of axon and synaptic connectivity have been linked to developmental hypoxia, but the fundamental mechanisms impacting motor function from altered connectivity are poorly understood. We investigated the effects of hypoxia on locomotor development in zebrafish. We found that developmental hypoxia resulted in decreased spontaneous swimming behavior in larva, and that this motor impairment persisted into adulthood. In evaluation of the diencephalic dopaminergic neurons, which regulate early development of locomotion and constitute an evolutionarily conserved component of the vertebrate dopaminergic system, hypoxia caused a decrease in the number of synapses from the descending dopaminergic diencephalospinal tract (DDT) to spinal cord motor neurons. Moreover, dopamine signaling from the DDT was coupled jointly to motor neuron synaptogenesis and to locomotor development. Together, these results demonstrate the developmental processes regulating early locomotor development and a requirement for dopaminergic projections and motor neuron synaptogenesis. Our findings suggest new insights for understanding the mechanisms leading to motor disability from hypoxic injury of prematurity.

Cell delivery to the pathological intervertebral disc (IVD) has significant therapeutic potential for enhancing IVD regeneration. The development of injectable biomaterials that retain delivered cells, promote cell survival, and maintain or promote an NP cell phenotype in vivo remains a significant challenge. Previous studies have demonstrated NP cell – laminin interactions in the nucleus pulposus (NP) region of the IVD that promote cell attachment and biosynthesis. These findings suggest that incorporating laminin ligands into carriers for cell delivery may be beneficial for promoting NP cell survival and phenotype. Here, an injectable, laminin-111 functionalized poly(ethylene glycol) (PEG-LM111) hydrogel was developed as a biomaterial carrier for cell delivery to the IVD. We evaluated the mechanical properties of the PEG-LM111 hydrogel, and its ability to retain delivered cells in the IVD space. Gelation occurred in approximately 20 minutes without an initiator, with dynamic shear moduli in the range of 0.9 – 1.4 kPa. Primary NP cell retention in cultured IVD explants was significantly higher over 14 days when cells were delivered within a PEG-LM111 carrier, as compared to cells in liquid suspension. Together, these results suggest this injectable laminin-functionalized biomaterial may be an easy to use carrier for delivering cells to the IVD.

Due to demographic trends towards an ageing population resource use of health care will increase. By collecting health-related costs via questionnaires, the impact of socio-economic variables and other medical factors can be examined. In addition, only patient reported resource use accounts for out-of-pocket payments. Thus, it is necessary to develop an appropriate tool to collect the health-related resource use in an elderly population.The development of the FIMA (questionnaire for the use of medical and non-medical services in old age) was carried out in 6 steps. These included the determination of necessary questionnaire contents based on a literature review and the wording and layout were defined. Finally the questionnaire was tested in a pilot study and was modified.All direct medical and non-medical resource use excluding transportation and time costs were recorded. Productivity losses were not included. The recall time frames differed according to resource categories (7 days, 3 months, 12 months). For the pilot study, 63 questionnaires were analysed. The response rate was 69%. The questionnaire took an average of 21 min to complete. Three quarters of respondents completed the questionnaire without help and 90% rated the difficulty as easy or even very simple. There was good agreement between self-reported health-related quality of life and the resource use of nursing and domestic help (phi coefficient values between 0.52 and 0.58).The FIMA is a generic questionnaire which collects the health-related resource use within the older population groups.

Presenting a paper at a journal club can be a daunting prospect for a trainee and one for which undergraduate medical education may leave the trainee feeling under-prepared. However, the ability to critically appraise and present an academic paper is a competency required of the trainee doctor.

Although anesthetists have long assumed that ketamine's role in neuroanesthesia is limited because of its association with increased intracranial pressure, this article presents a review of recent clinical literature suggesting otherwise. When ketamine is used as an adjuvant anesthetic agent along with mechanical ventilation to maintain normocapnia, ketamine does not have adverse cerebral hemodynamic effects. Furthermore, ketamine possesses a unique pharmacologic profile that provides analgesia, bronchodilation, and sympathetic stimulation, thereby reducing patients' vasoactive agent requirements. Caution must be exercised because of ketamine's action at the N-methyl-D-aspartate receptor (NMDAR), as ketamine may antagonize both neuroprotective and neurodestructive NMDAR-mediated pathways. Still, ketamine may prove to be a safe part of a neuroanesthetic regimen, and it should no longer be considered absolutely contraindicated as a result of its cerebral hemodynamic effects.

Chronic obstructive pulmonary disease (COPD) is associated with considerable morbidity and mortality and features a substantial economic burden.This article analyses the frequency of physician contacts and commonly provided services in the outpatient care of patients with COPD in Germany. Information on characteristic health care delivery in case of patients with COPD has been further used to construct basic scenarios of outpatient resource use.Altogether, 34 out of 150 respiratory specialists and 55 out of 350 general practitioners participated in the survey (response rates of 22.7 and 15.7%, respectively). Results point out, that the number of commonly provided services (a) is limited to a very basic set, (b) does not differ substantially according to severity of COPD, and (c) does not substantially vary between the stable phase of the disease and the presence of exacerbations.Despite its low level of evidence, the use of expert opinion can serve as a valuable and legitimate tool; especially when the literature does not provide any or only outdated information.

Background:The successful execution of lateral osteotomies in rhinoplasty is an important step that can influence the functional and aesthetic outcome of the procedure.Objective:This paper describes an alternative method for achieving mobilisation of the nasal bones by careful application of Walsham forceps during primary rhinoplasty.

Nonbiological total disc replacement is currently being used for the treatment of intervertebral disc (IVD) disease and injury, but these implants are prone to mechanical wear, tear and possible dislodgement. Recently, tissue-engineered total disc replacement (TE-TDR) has been investigated as a possible alternative to more fully replicate the native IVD properties. However, the performance of TE-TDRs has not been studied in the native disc space. In this study, MRI and microcomputed tomography imaging of the rat spine were used to design a collagen (annulus fibrosus)/alginate (nucleus pulposus) TE-TDR to a high degree of geometric accuracy, with less than 10% difference between TE-TDR and the native disc dimensions. Image-based TE-TDR implants were then inserted into the L4/L5 disc space of athymic rats (n = 5) and maintained for 16 weeks. The disc space was fully or partially maintained in three of five animals and proteoglycan and collagen histology staining was similar in composition to the native disc. In addition, good integration was observed between TE-TDR and the vertebral bodies, as well as remnant native IVD tissue. Overall, this study provides evidence that TE-TDR strategies may yield a clinically viable treatment for diseased or injured IVD.

Bullying as a subform of aggressive behaviour has not received much attention as a specific risk behaviour in adolescence. Especially the adverse health effects in relation to bullying have been barely discussed in Germany. The objective of this study is to present age- and gender-specific prevalences in bullying and to analyse the association between the different bullying roles and subjective health as well as risk behaviour.Data were obtained from the German part of the international WHO collaborative study "Health Behaviour in School-aged Children (HBSC)" in 2002. Overall, 5,650 school children aged 11-15 years were interviewed with a standardised questionnaire. Multivariate logistic regression models were used to analyse the association between bullying, psychosocial health and risk behaviour separately for girls and boys.About 17% of the boys and 10% of the girls aged 11-15 years were classified as repeated bullying perpetrators. About 10% of the school children are victims of being bullied several times a month. Another 3-5% of the adolescents belonged to the group of simultaneous victims and perpetrators (bully-victims). Perpetrators as well as victims showed strong associations with psychosocial health and risk behaviour. Independently of gender, victims were significantly more likely to report repeated psychosomatic complaints, adverse mental health and negative self-reported health (boys only), than uninvolved students. Especially for male perpetrators, strong associations with regular tobacco and alcohol use and repeated drunkenness were found, while these behaviour types were significantly less prevalent among victims. The bully-victim group is characterised by high rates of psychosomatic complaints and mental health problems (boys only).Bullying also seems to be widespread in schools in Germany and is strongly associated with subjective health and substance-related risk behaviour. The results suggest that bullying is a critical issue that requires increasing attention in health research. The unique health problems of victims and perpetrators suggest different intervention strategies for both groups.

Discussion on the potential for developing countries to develop trade in niche markets such as higher welfare standards has been highlighted with moves by the World Organisation for Animal Health (OIE) to set internationally agreed standards for animal welfare. This paper examines the existing and potential trade in value-added higher welfare products using case studies in the beef and poultry sectors from three countries in Africa, Asia and Latin America. It shows that at present there is only a small trade in these products but that this can have a major effect at a national level. In the beef export trade from Namibia, the existence of the only assurance scheme in Africa setting standards in hygiene, veterinary care and animal welfare has created a trusted, safe and healthy product and ensured that Namibia has grown into Africa's largest exporter of beef to the European Union. In Thailand, the broiler industry, which has enjoyed annual growth in the past 15 years, is developing value-added products to develop markets to counter competition from other countries. The development and implementation of standards for organic products in both Thailand and Argentina over the past decade have also resulted in growth in the export markets of these products. The paper concludes that there is growth potential for the sectors in all three markets which can be assisted by the development of OIE baseline standards.

High-dose methotrexate with leucovorin rescue was used alone or in combination with Adriamycin and cyclophosphamide for the treatment of 27 osteosarcoma patients with measurable indicators of disease. Three patients developed complete responses of measurable lesions, two had partial responses, two had static disease, one had symptomatic improvement, and one had return to normal of physical findings following treatment of a flat bone primary osteosarcoma. While the doses and frequency of administration of high-dose methotrexate differed from those used by previous investigators, these results suggest that aggressive treatment with high-dose methotrexate must be attempted to further evaluate its efficacy as single-agent therapy for osteosarcoma patients not eligible for adjuvant chemotherapy trials.

Eighteen patients with osteosarcoma, most of whom were adolescents, were examined for abnormalities of the brain by use of computed axial tomography. These studies were performed at 15-60 months (median 47 months) after the completion of adjuvant chemotherapy, which included high-dose methotrexate, cyclophosphamide, and Adriamycin. No abnormalities were found. The results of this study, together with the absence of brain lesions in published reports in children receiving high-dose methotrexate but no cranial irradiation, indicate that delayed neurotoxicity is not a major complication of this form of therapy in older children.

Nineteen young adult male smokers were compared to 19 adult male nonsmokers to determine if cigarette smoking resulted in any changes to anaerobic bacteria in dental plaque, to intraoral oxidation-reduction potential (Eh) levels, or to intraoral pH. There was no statistical difference between smokers and nonsmokers in the proportion of anaerobic bacteria found in dental plaque. There were no significant differences between smokers and nonsmokers with respect to the resting Eh in the floor of the mouth nor in the Eh in the region of buccal surface of the upper molars. The smoking of one cigarette resulted in a dramatic fall in Eh in both intraoral regions and this occurred in all subjects, both smokers and nonsmokers. The magnitude of this fall in Eh was similar in both groups. There were also uniform increases in pH, but these pH changes were much smaller in magnitude.

The clinical course of 18 consecutive children treated for primary retroperitoneal rhabdomyosarcoma was reviewed. At diagnosis, 8 patients had regional unresected tumor and 10 patients had disseminated tumor, including 3 patients with documented bone marrow infiltration by tumor. Following combined modality therapy, 14 of 18 patients achieved a greater than 50% tumor response (11 complete and 3 partial responses); 4 patients failed to respond and died of progressive disease within eight months of diagnosis. Among the 14 patients responding, 7 patients had subsequent reextension of active tumor three to 16 months (median, 9 months) following the onset of therapy. Three of the 7 remaining patients died of treatment complications, 2 of intestinal obstruction and 1 of disseminated histoplasmosis, within the first year of therapy and at post-mortem examination had no demonstrable tumor. Four patients are alive and free of active tumor for 10+, 10+, 32+ and 33+ months from diagnosis. Treatment complications have included hematopoietic depression, mucositis, enteritis, intestinal obstruction, excessive weight loss, malnutrition, and life-threatening infection. These results illustrate limitations in current combined modality therapy of retroperitoneal rhabdomyosarcoma and the necessity for future treatment modifications to both reduce morbidity and to improve survival.