Post-Radiotherapy Dysphagia in Head and Neck Cancer: Current Management by Speech-Language Pathologists

OPINION STATEMENT

Dysphagia, difficulty in eating and drinking, remains the most common side effect of radiotherapy treatment for head and neck cancer (HNC) with devastating consequences for function and quality of life (QOL). Over the past decade, 5-year survival has improved due to multiple factors including treatment advances, reduction in smoking, introduction of the human papillomavirus (HPV) vaccine and more favourable prognosis of HPV-related cancers. Increased prevalence of HPV-positive disease, which tends to affect younger individuals, has led to an elevated number of people living for longer with the sequelae of cancer and its treatment. Symptoms are compounded by late effects of radiotherapy which may lead to worsening of dysphagia for some long-term survivors or new-onset dysphagia for others. Speech-language pathology (SLP) input remains core to the assessment and management of dysphagia following HNC treatment. In this article, we present current SLP management of dysphagia post-radiotherapy. We discuss conventional treatment approaches, the emergence of therapy adjuncts and current service delivery models. The impact of adherence on therapy outcomes is highlighted. Despite treatment advancements, patients continue to present with dysphagia which is resistant to existing intervention approaches. There is wide variation in treatment programmes, with a paucity of evidence to support optimal type, timing and intensity of treatment. We discuss the need for further research, including exploration of the impact of radiotherapy on the central nervous system (CNS), the link between sarcopenia and radiotherapy-induced dysphagia and the benefits of visual biofeedback in rehabilitation.

Sustained year-round oceanographic measurements from Rothera Research Station, Antarctica, 1997-2017

Oceanographic changes adjacent to Antarctica have global climatic and ecological impacts. However, this is the most challenging place in the world to obtain marine data due to its remoteness and inhospitable nature, especially in winter. Here, we present more than 2000 Conductivity-Temperature-Depth (CTD) profiles and associated water sample data collected with (almost uniquely) full year-round coverage from the British Antarctic Survey Rothera Research Station at the west Antarctic Peninsula. Sampling is conducted from a small boat or a sled, depending on the sea ice conditions. When conditions allow, sampling is twice weekly in summer and weekly in winter, with profiling to nominally 500 m and with discrete water samples taken at 15 m water depth. Daily observations are made of the sea ice conditions in the area. This paper presents the first 20 years of data collection, 1997-2017. This time series represents a unique and valuable resource for investigations of the high-latitude ocean's role in climate change, ocean/ice interactions, and marine biogeochemistry and carbon drawdown.

Terms in journal articles associating with high quality: can qualitative research be world-leading?

Purpose

Scholars often aim to conduct high quality research and their success is judged primarily by peer reviewers. Research quality is difficult for either group to identify, however and misunderstandings can reduce the efficiency of the scientific enterprise. In response, we use a novel term association strategy to seek quantitative evidence of aspects of research that are associated with high or low quality.

Design/methodology/approach

We extracted the words and 2–5-word phrases most strongly associated with different quality scores in each of 34 Units of Assessment (UoAs) in the Research Excellence Framework (REF) 2021. We extracted the terms from 122,331 journal articles 2014–2020 with individual REF2021 quality scores.

Findings

The terms associating with high- or low-quality scores vary between fields but relate to writing styles, methods and topics. We show that the first-person writing style strongly associates with higher quality research in many areas because it is the norm for a set of large prestigious journals. We found methods and topics that associate with both high- and low-quality scores. Worryingly, terms associated with educational and qualitative research attract lower quality scores in multiple areas. REF experts may rarely give high scores to qualitative or educational research because the authors tend to be less competent, because it is harder to do world leading research with these themes, or because they do not value them.

Originality/value

This is the first investigation of journal article terms associating with research quality.

POS1138 PERSISTENCY OF DEPRESSIVE SYMPTOMS AND PHYSICAL PERFORMANCE IN KNEE OSTEOARTHRITIS

Background

Knee osteoarthritis (OA) is the most prevalent arthritic disorder, characterized by joint paint, which is exacerbated by chronic depressive episodes. Depression in knee OA is also associated with declines in physical activity level and greater disability; however, the impact of persistent depressive symptoms on physical performance remains unclear.

Objectives

To determine how the persistence of depressive symptoms affects functional capacity in knee OA.

Methods

Participants (n=2,212) were from the Osteoarthritis Initiative cohort and included individuals with radiographic disease (Kellgren-Lawrence grade ≥ 2) and complete data on study measures at baseline. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D; range 0-60) at baseline and the first three follow-up visits. Physical Performance was measured using 20-meter gait speed (meters per second) during follow-up at the first four annual visits. Persistency of depressive symptoms was operationalized as a cumulative exposure using average severity over time. Gait speed was standardized so that outcome estimates could be interpreted in standard deviations. Time-invariant confounders measured at study enrollment included demographic, socioeconomic, and lifestyle factors. Time-varying confounders assessed concurrent to CES-D scores were body mass index, analgesic medications, pain, and other knee OA signs and symptoms. Marginal structural models accounting for time-dependent confounding and selective attrition were the primary method of analysis. The outcome model included all potential statistical interactions between depressive symptoms and follow-up time indicators. Post-estimation linear combinations estimated time-specific effects of time-averaged CES-D scores on standardized gait speed and differences in physical performance between participants with (i.e., CES-D=16) and without (i.e., CES-D=0) depressive symptoms satisfying screening criteria for major depression.

Results

The interaction between depressive symptoms and time was statistically significant (P=<0.001). Time-specific associations indicated that the largest negative impact of depressive symptoms on physical performance was from baseline through year one (β = -0.0077; 95% CI: -0.0125, 0.0030). However, the effect of persistent depressive symptoms decreased over time and reversed in magnitude and directionality, evidenced by the time-specific associations between time-averaged CES-D scores from baseline through year one and year two and gait speed at year two (β = -0.0033; 95% CI: -0.0084, 0.0019) and year three (β = 0.0014; 95% CI: -0.0046, 0.0074), respectively. Consequently, the strongest negative affect of depressive symptoms on gait speed (β = -0.1232; 95% CI: -0.1998, -0.0473) between participants with and without depressive symptoms satisfying screening criteria for major depression was when depressive symptoms were first measured closest to the initial gait speed assessment.

Conclusion

In the contrast to the dose-dependent relationship between chronic depressive episodes and pain in knee OA, study findings imply that the negative effect of depressive symptoms on physical performance decreases over time with increasing depression persistency. These results may reflect diminishing marginal effects, where the largest impact on physical performance in knee OA is during the first depressive episode closest to initial gait speed assessment, especially when averaged against improvement in symptoms over the same duration.

Acknowledgements

The OAI is a public-private partnership comprised of five contracts (N01-AR-2-2258; N01-AR-2-2259; N01-AR-2-2260; N01-AR-2-2261; N01-AR-2-2262) funded by the National Institutes of Health, a branch of the Department of Health and Human Services, and conducted by the OAI Study Investigators. Private funding partners include Merck Research Laboratories; Novartis Pharmaceuticals Corporation, GlaxoSmithKline; and Pfizer, Inc. Private sector funding for the OAI is managed by the Foundation for the National Institutes of Health. This manuscript was prepared using an OAI public use data set and does not necessarily reflect the opinions or views of the OAI investigators, the NIH, or the private funding partners.

Disclosure of Interests

Rhea Mehta: None declared, Michelle Shardell: None declared, Alice Ryan: None declared, Yu Dong: None declared, Brock Beamer: None declared, Joseph Gallo: None declared, Elizabeth Stuart: None declared, Megan Schuler: None declared, Marc Hochberg Shareholder of: Dr. Marc C. Hochberg is the President of Rheumcon Corporation., Consultant of: Dr. Marc C. Hochberg receives consulting fees from Bioiberica SA, Bristol-Myers Squibb, Eli Lilly, EMD Serono, Galapagos, IBSA Biotechniq SA, Novartis Pharma AG, Pfizer, Plexxikon, Samumed LLC, Theralogix LLC, and TissueGene Inc., Alan Rathbun: None declared

Flickr: Organizing and Tagging Images Online

Flickr was launched when digital cameras first began to outsell analog cameras, and people were drawn to the site for the opportunities it offered them to store, organize, and share their images, as well as for the connections that could be made with other like-minded people. This article examines the links between Flickr’s success and how images are organized within the site, as well as the types of people and organizations that use Flickr and their motivations for doing so. Factors that have contributed to Flickr’s demise in popularity will be explored, and the article finishes with some suggestions for how Flickr could develop in the future, along with some conclusions for image organization.

An investigation of the online presence of UK universities on Instagram

Purpose

Rising tuition fees and a growing importance on league tables has meant that university branding is becoming more of a necessity to attract prospective staff, students, and funding. Whilst university websites are an important branding tool, academic institutions are also beginning to exploit social media. Image-based social media services such as Instagram are particularly popular at the moment. It is therefore logical for universities to have a presence on popular image-based social media services such as Instagram. The purpose of this paper is to investigate the online presence of UK universities on Instagram in an initial investigation of use.

Design/methodology/approach

This study utilizes webometric data collection, and content analysis methodology.

Findings

The results indicate that at the time of data analysis for this investigation (In the Spring of 2015), UK universities had a limited presence on Instagram for general university accounts, with only 51 out of 128 institutions having an account. The most common types of images posted were humanizing (31.0 percent), showcasing (28.8 percent), and orienting (14.3 percent). Orienting images were more likely to receive likes than other image types, and crowdsourcing images were more likely to receive comments.

Originality/value

This paper gives a valuable insight into the image posting practices of UK universities on Instagram. The findings are of value to heads of marketing, online content creators, social media campaign managers, and anyone who is responsible for the marketing, branding, and promoting of a university’s services.

Differential macrophage function in Brown Swiss and Holstein Friesian cattle

There is strong evidence that high yielding dairy cows are extremely susceptible to infectious diseases, and that this has severe economic consequences for the dairy industry and welfare implications. Here we present preliminary functional evidence showing that the innate immune response differs between cow breeds. The ability of macrophages (MØ) to kill pathogens depends in part on oxygen-dependent and independent mechanisms. The oxygen-dependent mechanisms rely on the generation of reactive oxygen and nitrogen species (ROS/RNS, respectively). ROS production has been shown to activate the inflammasome complex in MØ leading to increased production of the pro-inflammatory cytokine Interleukin-1β (IL-1β). Conversely RNS inhibits inflammasome mediated IL-1β activation, indicating a division between inflammasome activation and RNS production. In the present study MØ from Brown Swiss (BS) cattle produce significantly more RNS and less IL-1β when compared to cells from Holstein Friesian (HF) cattle in response to bacterial or fungal stimuli. Furthermore, BS MØ killed ingested Salmonella typhimurium more efficiently, supporting anecdotal evidence of increased disease resistance of the breed. Inhibition of autophagy by 3-methyladenine (3-MA) stimulated IL-1β secretion in cells from both breeds, but was more pronounced in HF MØ. Blocking RNS production by l-arginase completely abolished RNS production but increased IL-1β secretion in BS MØ. Collectively these preliminary data suggest that the dichotomy of inflammasome activation and RNS production exists in cattle and differs between these two breeds. As pattern recognition receptors and signaling pathways are involved in the assessed functional differences presented herein, our data potentially aid the identification of in vitro predictors of appropriate innate immune response. Finally, these predictors may assist in the discovery of candidate genes conferring increased disease resistance for future use in combination with known production traits.

Partial inhibition of gp130-Jak-Stat3 signaling prevents Wnt-β-catenin-mediated intestinal tumor growth and regeneration

Most colon cancers arise from somatic mutations in the tumor suppressor gene APC (adenomatous polyposis coli), and these mutations cause constitutive activation of the Wnt-to-β-catenin pathway in the intestinal epithelium. Because Wnt-β-catenin signaling is required for homeostasis and regeneration of the adult intestinal epithelium, therapeutic targeting of this pathway is challenging. We found that genetic activation of the cytokine-stimulated pathway mediated by the receptor gp130, the associated Jak (Janus kinase) kinases, and the transcription factor Stat3 (signal transducer and activator of transcription 3) was required for intestinal regeneration in response to irradiation-induced damage in wild-type mice and for tumorigenesis in Apc-mutant mice. Systemic pharmacological or partial genetic inhibition of gp130-Jak-Stat3 signaling suppressed intestinal regeneration, the growth of tumors in Apc-mutant mice, and the growth of colon cancer xenografts. The growth of Apc-mutant tumors depended on gp130-Jak-Stat3 signaling for induction of the polycomb repressor Bmi-1, and the associated repression of genes encoding the cell cycle inhibitors p16 and p21. However, suppression of gp130-Jak-Stat3 signaling did not affect Wnt-β-catenin signaling or homeostasis in the intestine. Thus, these data not only suggest a molecular mechanism for how the gp130-Jak-Stat3 pathway can promote cancer but also provide a rationale for therapeutic inhibition of Jak in colon cancer.

A short history of providing medical history within the British medical undergraduate curriculum

This article aims to discuss the history of medical history in the British medical undergraduate curriculum and it reviews the main characters and organisations that have attempted to earn it a place in the curriculum. It also reviews the arguments for and against the study of the subject that have been used over the last 160 years.

Ginkgo biloba for tinnitus

BACKGROUND

Tinnitus can be described as the perception of sound in the absence of external acoustic stimulation. At present no specific therapy for tinnitus is acknowledged to be satisfactory in all patients. There are a number of reports in the literature suggesting that Ginkgo biloba may be effective in the management of tinnitus. However, there also appears to be a strong placebo effect in tinnitus management.

OBJECTIVES

To assess the effect of Ginkgo biloba in patients who are troubled by tinnitus.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 4 2003), MEDLINE (1966 - 2003), EMBASE (1974 - 2003), and reference lists of identified publications. Date of the most recent search was December 2003.

SELECTION CRITERIA

Adults (18 years and over) complaining of tinnitus. Adults with a primary complaint of cerebral insufficiency where tinnitus forms part of the syndrome.

DATA COLLECTION AND ANALYSIS

Both reviewers independently extracted data and assessed trials for quality.

MAIN RESULTS

Twelve trials were identified from the search as being relevant to the review. Ten trials were excluded on methodological grounds. No trials of tinnitus in cerebral insufficiency reached a satisfactory standard for inclusion in the review. There was no evidence that Ginkgo biloba was effective for the primary complaint of tinnitus. The incidence of side effects was small.

REVIEWERS' CONCLUSIONS

The limited evidence did not demonstrate that Ginkgo biloba was effective for tinnitus which is a primary complaint. There was no reliable evidence to address the question of Ginkgo biloba for tinnitus associated with cerebral insufficiency.

Interactions between cutaneous afferent inputs to a withdrawal reflex in the decerebrated rabbit and their control by descending and segmental systems

Previous studies have suggested that activation of nociceptive afferents from the heel recruits a supraspinal mechanism, which is modulated by adrenergic descending inhibition, that augments withdrawal reflexes in medial gastrocnemius (MG) motoneurones. To test this idea, we have studied the temporal evolution of reflexes evoked in MG by electrical stimulation of sural nerve A(beta)-, A(delta)- and C-fibre axons at 1 Hz, in decerebrated rabbits. Reflexes were analysed in three time bands, estimated to accord to afferent drive from A(beta)- (phase 1), A(delta)- (phase 2) and C-fibre (phase 3) inputs. Stimulation of A(delta)- and C-fibres gave significant temporal summation of all reflexes. The alpha(2)-adrenoceptor antagonist RX 821002 ((2-(2,3-dihydro-2-methoxy-1,4-benzodioxin-2-yl)-4,5-dihydro-1-H-imidazole)-HCl) (100 microg intrathecal (i.t.)) potentiated, and the alpha(2)-agonist dexmedetomidine (1-30 microg i.t.) depressed all reflexes per se, but the effects of these drugs on temporal summation were secondary to changes in baseline excitability. When C-fibres were stimulated, the N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (1 mg i.t.) reduced temporal summation of phase 2 and 3 but not phase 1 reflexes. Spinalisation at L1 in the absence of drugs increased phase 2 and 3 reflexes but had no effect on phase 1, whereas spinalisation after RX 821002 resulted in decreased phase 1 responses with no significant change in later phases. Spinalisation in the presence of dizocilpine resulted in small reductions in phase 3 reflexes only. In all cases spinalisation virtually abolished temporal summation. In spinalised animals, dizocilpine selectively reduced late reflexes, and the opioid antagonist naloxone (100 microg i.t.) augmented all reflexes but gave rise to temporal subtraction of reflexes when C-fibres were stimulated.The present experiments have revealed a number of novel and important features of the sural-MG reflex pathway: (i) activity in fine afferent axons augments the reflexogenic potential of all subsequent afferent input, thereby allowing all afferent drive from the sural field to contribute to withdrawal of the heel; (ii) endogenous adrenergic control of this reflex pathway is completely non-selective; (iii) there is a non-adrenergic element of descending inhibition that is selective for the late components of MG reflex responses, and this element is directed particularly against transmission through NMDA receptors; (iv) temporal summation in this reflex is dependent on NMDA receptor-dependent and -independent mechanisms; and (v) this temporal summation is in some way dependent on the integrity of descending pathways.

Dimorphic expression of medial basal hypothalamic-preoptic area calbindin-D(28K) mRNA during perinatal development and adult distribution of calbindin-D(28K) mRNA in Sprague-Dawley rats

The calcium-binding protein, calbindin (CALB) is: (a) distributed throughout the central nervous system (CNS), (b) abundant in neurons and, (c) thought to act as a buffer by binding intracellular calcium, mediating neurogenesis (cell profileration) and neuronal programmed cell death. Using Northern analysis, CALB mRNA distribution was characterized in 12 different adult brain regions. Additionally, CALB mRNA levels were characterized in the medial basal hypothalamus (MBH) and preoptic area (POA) in perinatal male and female rats, in order to compare this mRNA pattern to the dimorphic MBH-POA CALB protein profile our laboratory previously reported. Three CALB mRNA species were detected (at 1.9, 2.8 and 3.2 kilobase pairs) in all CNS regions. The smallest mRNA transcript (at 1.9 kilobase pairs) was the most abundant of the three CALB mRNAs. To quantify these mRNA signals, CALB mRNA levels were normalized to 18s ribosomal RNA bands. Among the various adult brain sites assayed, the cerebellum expressed the highest CALB mRNA signals. High CALB mRNAs were observed in the MBH-POA, olfactory bulb and hippocampal regions. Moderate CALB mRNA levels were seen in the striatum and frontal cortex while moderate to low CALB mRNA levels were observed in the posterior cortex, entorhinal cortex, midbrain, pons, thalamus and medulla. During perinatal development, MBH-POA CALB mRNA levels were lowest at gestation day (GD) 18, increased four-fold in newborns and remained at moderate levels during early postnatal development. Male CALB mRNA levels were notably greater than female values at GD 18 and in newborns. Whereas, at PND 2, the CALB mRNA levels were approximately equivalent in males and females. These findings suggest that in the adult CNS CALB mRNAs vary among different brain regions. The present male vs. female MBH-POA CALB mRNA levels confirm previously reported dimorphic protein patterns of MBH-POA CALB during perinatal development. Thus, the genesis of sexually dimorphic structures may be influenced by the dimorphic CALB expression in the MBH-POA region.

Healing through integration: promoting wellness in cardiac rehabilitation

This case study illustrates the basic life processes, transitions, and meanings of a woman with diagnosed coronary artery disease who participated in an innovative outpatient program of cardiac rehabilitation. Data gathering and analysis were accomplished using the phenomenologic procedures outlined by Spiegelberg and van Manen. A formulated structure, healing through integration, was generated from the interpretation of case study data, as well as the data of 15 other adult patients who participated in a program of outpatient cardiac rehabilitation. This structure provides a framework for nursing assessment and the implementation of relevant mind, body, social, spiritual, and behavioral interventions designed to assist individuals in integrating health-enhancing behaviors and recovery following a cardiac health crisis.

Comparison of a computer simulation program and a traditional laboratory practical class for teaching the principles of intestinal absorption

Here we describe an evaluation of the effectiveness, compared with a traditional laboratory, of an interactive computer-assisted learning (CAL) program, which simulates a series of experiments performed using isolated, everted sacs of rat small intestine. The program is aimed at undergraduate students of physiology and is designed to offer an alternative student-centered learning approach to the traditional laboratory-based practical class. The evaluative study compared two groups of second-year undergraduate students studying a module on epithelial transport: one group worked independently using the CAL program and associated learning materials, and the other group followed a conventional practical class approach, working in the laboratory under supervision. Knowledge gain of each group was measured by means of a test consisting of a range of question types (e.g., short-answer factual, calculation, interpretation) given to students before and after the module. Student attitude to both approaches was assessed by questionnaire, and the resource requirements were also compared. It was found that the knowledge gain of both groups of students was the same, that students had a positive attitude toward using CAL programs of this type, and that the cost of the conventional laboratory-based approach was five times greater. The potential for integrating CAL programs into the undergraduate curriculum is discussed.

Surgical management of the thoracic outlet compression syndrome

There is some disagreement about whether the first rib should be excised in the presence of a cervical rib for the relief of the thoracic outlet compression syndrome (TOCS). Over a 14-year period (1975-1988) 58 patients have undergone surgery for TOCS. Forty-four patients (76 per cent) had vascular symptoms, 28 (48 per cent) with a neurological component; 11 (19 per cent) had only neurological symptoms. Thirty-six patients (62 per cent) had the first rib excised; 19 (33 per cent) had a cervical rib excised; two (3 per cent) had a division of fibrous bands; and one patient had a large transverse process resected. Follow-up details were available on 53 patients (91 per cent). Overall 38 (72 per cent) were cured of their symptoms, 11 (21 per cent) had a significant improvement, and four (8 per cent) showed no improvement. There was no significant difference between the results following excision of a cervical rib or of a first rib in terms of relief of symptoms. In patients with TOCS who have a cervical rib, excision of the cervical rib alone without excision of the first rib would appear to be an appropriate treatment.

Interactions between opioid peptides and adrenaline-containing neurons modulate luteinizing hormone secretion in male rats

Abstract There is increasing evidence that the opioid inhibition of luteinizing hormone (LH) secretion is mediated, at least in part, by catecholaminergic mechanisms. This study determined the effects of selective manipulation of noradrenergic and adrenergic systems on the ability of opiate receptor blockade to induce the release of LH in adult male rats. Selective depletion of hypothalamic noradrenaline levels by 80% following 6-hydroxydopamine infusions into the central tegmental tract did not alter the 2- to 3-fold increase in serum LH levels following opiate receptor blockade with naloxone (2.5 mg/kg). In contrast, both selective depletion of hypothalamic adrenaline by prior treatment with the phenylethanolamine N-methyltransferase inhibitor, LY134046 (2 x 50 mg/kg) and non-selective depletion of all three catecholamines with alpha-methyl-p-tyrosine (250 mg/kg), abolished the naloxone-induced increase in LH. These results suggest that the inhibition of LH secretion by endogenous opioid peptides is influenced by catecholaminergic neurotransmission and further support the view that adrenaline rather than noradrenaline or dopamine is of importance in this context.

A CHO cell line resistant to deoxycholic acid

Spontaneous mutants resistant to deoxycholic acid (DCA) have been selected from a CHO cell line AuxBl. One of the colonies or 'lines' selected was subsequently mutagenized by ethylmethanesulfonate (250 micrograms/ml) and a more resistant cell, named alpha 3, has been selected. When AuxBl and alpha 3 were exposed to graded concentrations of DCA for 1 h, the LD50 for the mutant strain alpha 3 was 0.66 mM compared to 0.26 mM for the parental line. AuxBl. alpha 3 showed a cross-resistance compared to AuxBl with respect to cholic acid and chenodeoxycholic acid and to other acidic lipids such as linoleic and oleic acids. As an initial step in characterization of the cell lines, the amounts of different phospholipids from whole cell extracts of the parental and mutant strains have been measured after thin-layer chromatography (TLC) separation. The results obtained demonstrated that the fraction of sphingomyelin and phosphatidylcholine over the total phospholipids was slightly increased in the resistant cell line, alpha 3, compared to the parental line, AuxBl (54.9% +/- 1.04 compared to 51.2% +/- 0.3, P = 0.01). Further characterization of cell lines resistant to bile acids could lead to the identification of the cellular target of bile acid action.

Induction of sister chromatid exchanges in murine colonic tissue

As cancers of the large bowel arise primarily in the epithelial cells of the colon, measurement of genetic damage induced in those cells may aid in elucidating contributing factors in the etiology of the disease. Accordingly, procedures for the in vivo measurement of sister chromatid exchanges (SCE) have been adapted for use with colonic cells. Agar-coated 5-bromo-2'-deoxyuridine (BrdUrd) tablets were implanted (s.c.) in mice and colonic tissue prepared for measurement of SCE 48 hr later. When mice were treated by intraperitoneal injection with 20 mg/kg 1,2-dimethylhydrazine (DMH), a colon carcinogen, a significant increase over control SCE frequencies was found when treatment with carcinogen occurred in the interval from 14 hr before to 36 hr following BrdUrd administration. Treatment with DMH 2 hr following implantation of BrdUrd produced a dose-dependent increase in SCE frequencies, with the highest dose (20 mg/kg) resulting in frequencies approximately twice those of controls. Dimethylhydrazine was not found to be effective in inducing SCE in bone marrow cells of mice. As SCE can be induced by carcinogens and mutagens, measurement of SCE in colonic epithelium may be useful in identifying potential colon carcinogens.

SANITATION IN SERBIA

We must maintain health programs in Serbia according to Major Stuart, who tells plainly of conditions as his party found them. Serbia, with other Balkan countries, is a menace to the health of the Western world. Typhus and malaria are endemic, while tuberculosis and other communicable diseases enfeeble the people.