273 ‘HOME ON TIME’: MULTIDISCIPLINARY INTERVENTION REDUCES LENGTH OF STAY AND DELAYS IN CARE TRANSFERS ON AN ACUTE GERIATRIC MEDICINE WARD

Background

Unnecessarily prolonged hospital admission can have a profound effect on a frail, older person’s confidence, mood, functional status and cognition.This study examined whether a structured multidisciplinary intervention, embedded within an acute geriatric medicine ward, could reduce unnecessary days in hospital for acutely unwell older patients.

Methods

The study site is a 28-bed acute geriatric medicine ward in a large urban teaching hospital; data was collected from 1/1/22 to 11/4/22. Patients aged ≥70 years and admitted to the ward were randomly allocated to the Home On Time (HOT) Pathway (n=50) or usual care (n=100). All patients were cared for by a specialist geriatric team. The HOT Pathway involved daily multidisciplinary team (physiotherapy, nursing, occupational therapy, social work and medical) huddles focusing on enhanced communication, early discharge planning and identification of barriers to discharge home. Huddles typically lasted for <15 minutes.

Results

Almost two-thirds (92/150) of the study sample (mean age 83 years, 60% female) were discharged directly from the ward while one-fifth (29/150) were transferred for rehabilitation and one-tenth ultimately to long term care (16/150). The average acute ward Length-of-Stay (LOS) for HOT pathway patients was 10.4 days, compared to 14.4 days for usual care. The average LOS for HOT pathway patients discharged directly home (i.e. not via rehabilitation or to long-term care) was 8.0 days, compared to 10.2 days for usual care. One-fifth (10/50) of HOT pathway patients were discharged home within 48 hours of admission compared to one tenth (10/100) of usual care patients.

Conclusion

A structured, multidisciplinary intervention focusing on enhanced communication and early discharge planning within a geriatric medicine ward can reduce length of inpatient stay, delays in transitions of care and increase the rate of discharge home within 48 hours, potentially averting complications related to prolonged hospital admission.

Research ethics systems, processes, and awareness across Europe: Radiography research ethics standards for Europe (RRESFE)

INTRODUCTION

The Radiography Research Ethics Standards for Europe (RRESFE) project aims to provide a cross-sectional snapshot of current research ethics systems, processes, and awareness of such, across Europe together with identifying the associated challenges, education, and training needs.

METHODS

A cross-sectional online survey targeting radiography researchers in Europe was conducted. Data collection took place between April 26 and July 12, 2021, using a snowball sampling approach. Descriptive and analytical statistics were used to identify trends in research ethics frameworks across Europe.

RESULTS

285 responses were received across 33 European and 23 non-European countries. Most (n = 221; 95%) European respondents stated ethics approval is required before commencing research in their country. Requirements around research ethics approval and awareness of such requirements varied by European region (X² (2, n = 129) = 7.234, p = 0.013) and were found to differ depending on the type of research participant and study design. Additionally, European respondents reported ethics approval is a national requirement more often than their non-European counterparts (X² (1, n = 282) = 4.316, p = 0.049). Requirements for ethics approval were also associated with the undergraduate programme duration (2-year vs. 3-year vs. 3.5 year vs. 4-year vs. multiple programme durations; X² (4, n = 231) = 10.075, p = 0.016) and availability of postgraduate training (postgraduate training available vs. postgraduate training not available; X² (1, n = 231) = 15.448, p = <0.001) within respondents' country.

CONCLUSION

Respondents from countries with longer programme durations/availability of multiple programme lengths, availability of postgraduate training, and establishment of European Qualifications Framework Level 6 were generally associated with less uncertainty and more comprehensive research ethics requirements.

IMPLICATIONS FOR PRACTICE

Results are informative of the current status of research ethics within evidence-based radiography.

Research ethics training, challenges, and suggested improvements across Europe: Radiography research ethics standards for Europe (RRESFE)

INTRODUCTION

The Radiography Research Ethics Standards for Europe (RRESFE) project aimed to provide a cross-sectional view of the current state of radiography research ethics across Europe. This included investigating education and training in research ethics, and identifying the key challenges and potential improvements associated with using existing research ethics frameworks.

METHODS

This cross-sectional online survey targeting radiography researchers in Europe was conducted between April 26 and July 12, 2021. Descriptive and analytical statistics were used to identify research ethics education and training trends. Content analysis of qualitative responses was employed to identify significant challenges and proposed improvements in research ethics frameworks of practice.

RESULTS

There were 232 responses received across 33 European countries. Most (n = 132; 57%) respondents had received some research ethics training; however, fewer participants had received training on safeguarding vulnerable patients (n = 72; 38%), diversity and inclusivity (n = 62; 33%), or research with healthy volunteers (n = 60; 32%). Training was associated with a greater perceived importance of the need for research ethics review (p = 0.031) and with the establishment of EQF Level 6 training (p = 0.038). The proportion of formally trained researchers also varied by region (p = <0.001). Time-to-ethics-approval was noted as the biggest challenge for professionals making research ethics applications.

CONCLUSION

Early and universal integration of research-oriented teaching within the radiography education framework which emphasises research ethics is recommended. Additionally, study findings suggest research ethics committee application and approval processes could be further simplified and streamlined.

IMPLICATIONS FOR PRACTICE

The survey contributes to a growing body of knowledge surrounding the importance of education and training in research ethics for assuring a high standard of research outputs in Radiography and has identified hurdles to obtaining research ethics approval for further investigation and address.

Are radiographers an influencing factor in the radiation protection practices of speech-language therapists performing videofluoroscopic swallowing studies?

INTRODUCTION

A videofluoroscopic swallowing study (VFSS) is a fluoroscopic examination conducted by radiographers and speech-language therapists (SLTs) to assess dysphagia. Given the potential of SLTs to feed patients during the procedure, they may be exposed to radiation. The research aimed to assess radiation protection practices utilised by SLTs to determine if radiographers have a role in providing ongoing practical education.

METHODS

An online questionnaire was distributed to SLTs from six countries (Australia, Canada, Ireland, New Zealand, United Kingdom and United States of America). Responses were analysed quantitatively using frequencies and chi-square analysis (p = 0.05) and supported by written comments.

RESULTS

A total of 224 responses were analysed. Thyroid shields (94%) were used more frequently than full aprons (72%). Differences (p < 0.0001) were seen between Australian and USA participants regarding the use and position of radiation monitors; 43% of Australian participants stating they always used a monitor, compared to 75% of USA participants. Nearly all Australian SLTs wore monitors under shielding (92%) and at waist level (69%), while USA participants reported wearing them outside shielding (97%) and at thyroid level (94%). Participants' radiation practice was influenced primarily by other SLTs (64%), followed by radiographers (57%). However, written comments revealed the significance of the radiographer in providing training as "radiographers are excellent at ensuring we [use] right equipment, stand in the right places and use exposure monitoring".

CONCLUSION

SLTs did not always adopt the ICRP principle of shielding and there were inconsistencies with regards to the use and placement of radiation monitors. Radiographers are well positioned to provide advice with regards to safe practice.

IMPLICATIONS FOR PRACTICE

Opportunities to enhance radiation protection practices are evident, as is the advising role of radiographers.

A randomized controlled trial of differing doses of postcesarean enoxaparin thromboprophylaxis in obese women

OBJECTIVE

To compare two enoxaparin dosing strategies at achieving prophylactic anti-Xa levels in women with a body mass index (BMI) ⩾35 (kg m(-2)) postcesarean delivery.

STUDY DESIGN

Women with BMI ⩾35 were randomized to receive prophylactic enoxaparin at a fixed dose of 40 mg daily or weight-based dosing of 0.5 mg kg(-1) twice daily. The primary outcome was the proportion of subjects with peak anti-Xa levels in the prophylactic range of 0.2 to 0.6 IU ml(-1).

RESULT

From August 2013 through February 2014, 84 demographically similar women completed the protocol. In the weight-based group, 88% (37/42) of the women reached prophylactic anti-Xa levels versus 14% (6/42) in the fixed dose group (odds ratio 44.4, 95% confidence interval 12.44, 158.48, P<0.001). No anti-Xa level exceeded 0.48 IU ml(-1). There were no venous thromboembolic or bleeding events requiring reoperation or transfusion in either group.

CONCLUSION

Compared with fixed dosing daily, weight-based dosing twice daily more effectively achieved prophylactic anti-Xa levels without reaching the therapeutic range.

Total synthesis of the cyanobacterial metabolite nostodione A: discovery of its antiparasitic activity against Toxoplasma gondii

A diversity-oriented total synthesis of nostodione-A and analogues and their antiparasitic activity againstToxoplasma gondiiis reported.

Rheumatoid arthritis: a novel radiographic projection for hand assessment

Rheumatoid arthritis (RA) is the most common form of inflammatory disease, affecting 1-2% of the population. Posteroanterior (PA) and Brewerton projections are well established in radiographic practice for scoring and monitoring RA, but there is little evidence to demonstrate the diagnostic efficacy of these techniques. This work, by varying the positioning of a cadaveric hand, investigates whether an alternative radiographic projection could yield greater diagnostic information than the traditional techniques. Phase I of the study evaluated moving the hand 15 degrees from the anteroposterior position and then in 5 degrees increments in four directions: medial rotation, lateral rotation, flexion of the wrist and extension of the wrist. Phase II of the study took the optimum projections from Phase I and further manipulated these positions in a direction at right angles to the original position. Images were scored based on joint space visualisation in 29 joints. Results demonstrated that significantly higher diagnostic efficacy was evident with 15 degrees lateral rotation of the hand or 15 degrees flexion at the wrist compared to the Brewerton projection. Either projection is recommended, but on the basis of patient comfort, the latter of these novel positions, now known as the UCD projection, was chosen as the optimum procedure to replace the Brewerton projection. The value of using cadavers for the establishment of optimum radiographic procedures is highlighted.

Nonclinical aspects of biopharmaceutical development: discussion of case studies at a PhRMA-FDA workshop

Robust assessments of the nonclinical safety profile of biopharmaceuticals are best developed on a scientifically justified, case-by-case basis, with consideration of the therapeutic molecule, molecular target, and differences/similarities between nonclinical species and humans (ICH S6). Significant experience has been gained in the 10 years ensuing since publication of the ICH S6 guidance. In a PhRMA-FDA-sponsored workshop, "Nonclinical Aspects of Biopharmaceutical Development," industry and US regulatory representatives engaged in exploration of current scientific and regulatory issues relating to the nonclinical development of biopharmaceuticals in order to share scientific learning and experience and to work towards establishing consistency in application of general principles and approaches. The proceedings and discussions of this workshop confirm general alignment of strategy and tactics in development of biopharmaceuticals with regard to such areas as species selection, selection of high doses in toxicology studies, selection of clinical doses, the conduct of developmental and reproductive toxicity (DART) studies, and assessment of carcinogenic potential. However, several important aspects, including, for example, appropriate use of homologues, nonhuman primates, and/or in vitro models in the assessment of risk for potential developmental and carcinogenic effects, were identified as requiring further scientific exploration and discussion.

Pancratistatin: a natural anti-cancer compound that targets mitochondria specifically in cancer cells to induce apoptosis

The major hurdle in the fight against cancer is the non-specific nature of current treatments. The search for specific drugs that are non-cytotoxic to normal cells and can effectively target cancer cells has lead some researchers to investigate the potential anti-cancer activity of natural compounds. Some natural compounds, such as Taxol, have been shown to possess some anti-cancer potential. Pancratistatin (PST) is a natural compound that was isolated from the spider lily Pancratium littorale and shown to exhibit antineoplastic activity. The specificity of PST to cancer cells and the mechanism of PST's action remain unknown. This study provides a detailed look at the effect of PST treatment on cancerous and normal cells. Our results indicate that PST induced apoptosis selectively in cancer cells and that the mitochondria may be the site of action of PST in cancer cells. A biochemical target available specifically in cancer cells may lead to the development of new and more effective cancer fighting agents.

The influence of N-dialkyl and other cationic substituents on DNA intercalation and genotoxicity

DNA intercalation by small chemical molecules can result in frameshift mutagenesis and chromosomal breakage. With evidence mounting that broadly diverse structures are capable of intercalating between DNA base pairs, it becomes important to better define those structural features that enhance intercalation strength and those that confer genotoxicity particularly among those intercalators that do not have the classical planar tricyclic fused ring structure. A chemical substituent that is present on many pharmaceutical and other biologically active molecules is the N-dialkyl group. In the present study, we investigate if and how the presence of an aromatic N-dialkyl or other cationic group affects the genotoxicity and DNA intercalation ability of 26 selected acridines, phenothiazines, benzophenones, triphenylethylenes and other classes of molecules. The data were obtained from the literature, from experiments using a cell-based DNA intercalation assay, and from modeling studies using a three-dimensional computational DNA docking program. It is demonstrated that cationic substitution can enhance both genotoxicity and electrostatic interactions within a chemical/DNA intercalation complex.

A new structural motif for rigid C2-symmetrical propeller-shaped 1,2-diamines employing double aromatic pi-stacking

Utilization of double aromatic pi-stacking interactions on a 2,3-diaminobutane framework provides a new motif for structurally rigid C2-symmetrical propeller-shaped chiral 1,2-diamines.

Studies directed towards the refinement of the pancratistatin cytotoxic pharmacophore

Two deoxy-analogues of the anticancer/antiviral agent pancratistatin containing functionality complementary to the minimum structural pharmacophore were synthesized and subjected to anticancer screening. One of the analogues exhibited selective inhibition of certain tumor cell lines but was significantly less potent than the natural products. The minimum structural pharmacophore has now been refined from eight to three possible structures.

Communicating pain and pain management needs after surgery

This descriptive study explored how patients communicate their pain and pain management needs after surgery. Thirty postoperative patients were interviewed. The majority described avoiding or delaying communicating their pain at some point during their hospitalization. Reasons for decreased pain communication included not wanting to complain; not wanting to take the provider away from other patients; avoiding unpleasant analgesic side effects; and not wanting to take "drugs." Postoperative patients may be unclear about their role in pain management. Pain management communication problems identified in this study could be used to design intervention studies to improve pain communication and consequent pain relief.

Reported adoption of dietary fat and fiber recommendations among consumers

OBJECTIVE

To identify constraints in adopting dietary fat and fiber recommendations.

DESIGN

A questionnaire was mailed to a sample of the general population, a convenience sample of persons with heart disease and cancer in 11 states, and registered dietitians in 5 states. The survey included questions on demographic and attitudinal factors that were correlated with specific practices to reduce fat intake and increase fiber intake.

SETTING

From the general population sample of 6,206 eligible respondents (return rate of 51.5%), those selected were respondents who indicated that they would adopt a dietary recommendation if it were good for them (n = 2,682). Subsamples from the general population were matched to 362 registered dietitians and 147 persons with cancer or heart disease on selected demographic variables. Factors associated with adoption of specific behaviors were identified.

STATISTICAL ANALYSIS PERFORMED

Statistical analysis included chi 2, factor analysis, and analysis of variance.

RESULTS

The majority of persons who said they would adopt a fat-reducing behavior if it were good for their health reported practicing that behavior often or usually. More than 60% reported consuming whole grains; however, only 15% reported eating fruits and vegetables frequently. Among the general population sample, those more likely to practice a behavior had the following characteristics: female, college educated, older than 60 years, white, higher income, no children younger than 18 years, perceived health status as excellent, and absence of chronic disease. Registered dietitians and those with chronic disease were also more likely to follow dietary fat and fiber recommendations.

APPLICATIONS

Nutrition education messages that lead to increased consumption of dietary fiber need to be developed. Nutrition educators should provide strategies for consumers for increasing use of fruits and vegetables in all meals. Good taste and convenience are critical components. The food industry may assist by providing a wider array of convenience entrees or side dishes that feature produce and whole grains.

A stage-of-change classification system based on actions and beliefs regarding dietary fat and fiber

PURPOSE

The objectives of this study were to develop a stage-of-change classification system and to determine the degree to which various adult subgroups have adopted the behavioral changes necessary to achieve a low-fat and/or high-fiber diet as recommended by the Dietary Guidelines for Americans.

DESIGN

The study used a mail survey randomly sent to 7110 adults.

SETTING

The survey was conducted in 11 states and the District of Columbia.

SUBJECTS

The random sample included males and females over age 18. Of the eligible respondents, 3198 (51.5%) were included in this analysis, with 2004 and 2066 unambiguously classified into stages of change for fat and fiber, respectively.

MEASURES

Stage of change was defined by an algorithm based on self-reported intent and behaviors to limit fat and/or increase fiber.

RESULTS

45% of the respondents were classified as being in action/maintenance for fat and 38% for fiber. Women, older adults, individuals with advanced education, persons with diet-related chronic disease, people with higher levels of relevant nutrition knowledge and attitudes, and persons who indicated that health concerns were a primary influence on their diet were more likely to be in action/maintenance than other respondents.

CONCLUSIONS

The algorithm in this study presents a model that more closely reflects the proportions of the adult population that have achieved low-fat diets and classifies a greater proportion in the preparation stage than classification systems in previous studies.

Antineoplastic agents. 362. Isolation and X-ray crystal structure of dibromophakellstatin from the Indian ocean sponge Phakellia mauritiana

Bioassay-guided isolation procedures using human tumor cell lines led to isolation of dibromophakellstatin (4) from the Republic of Seychelles sponge Phakellia mauritiana. The isolation, X-ray crystal structure elucidation, absolute stereochemistry, and antineoplastic activity have been summarized. P. mauritiana was also found to contain dibromophakellin (1), debromohymenialosine (2), thymidine, deoxyuridine, and thymine.

Non-surgical approaches to stones in the biliary tree

Medical treatment of cholesterol gall stones aims to dissolve the stones leaving the biliary tract stone-free and the gall bladder in situ. The introduction of extracorporeal shock wave lithotripsy and contact solvent therapy with methyl tert butyl ether have revolutionised the medical management of both gall bladder stones and bile duct stones which are too large to be treated by sphincterotomy. Both approaches represent a major advance over cheno- and ursodeoxycholic acid which are effective in less than 30% of cases and require prolonged therapy. All medical treatments require a functioning gall bladder and suffer from relapse rates in the order of 10% per annum. Secondary prophylaxis is expensive and the rate of compliance and long term safety have yet to be established.

Direct measurement of fast axonal organelle transport in chronic ethanol-fed rats

While indirect methods have been used, direct evaluation and measurement of the fast axonal transport system itself in chronic ethanol-fed rats have not been carried out previously. We evaluated this system using analog and digital image enhancement of differential interference contrast optical images in real time to assess the effect of ethanol on fast intra-axonal organelle traffic in rat sural nerve. A radiolabeling method for evaluating fast axonal transport was used in similar animals to compare the indirect and direct techniques. Also, the concentration of organelles (mitochondria, large and small clear vesicles, dense vesicles, and membranous whorls) in the annulospiral sensory nerve endings of muscle spindles from a foot muscle (flexor digitorum brevis) of these same animals was quantitated from electron micrographs. Rats were fed an ethanol-containing liquid diet for one to five months. Three observations were made; (1) There was no statistically significant change in the mean organelle speed in the anterograde direction, but the mean organelle speed in the retrograde direction increased 11%, 9%, and 17% (statistically significant) at 3, 4, and 5 months of ethanol exposure, respectively. (2) Significant increases in organelle content of sensory nerve endings were seen at 2 and 3 months of intoxication. (3) Increases in organelle densities in terminals were transitory and returned to normal in the face of on-going ethanol administration. We conclude: (1) There is no permanent impairment of fast axonal organelle transport in this model after 5 months of exposure. (2) Sensory endings on muscle spindles show transitory increases in organelle density. (3) Retrograde speed increases may be a partial compensatory mechanism to help restore normal terminal organelle density.(ABSTRACT TRUNCATED AT 250 WORDS)

Complications of liver biopsy: the incidence of pneumothorax and role of post biopsy chest x-ray

The incidence of pneumothorax and role of post biopsy chest x-ray were assessed in a prospective study of 120 consecutive patients using a standard biopsy technique. The incidence of pneumothorax was 0.8%. Post biopsy chest x-ray was not found to improve accuracy of diagnosis compared with clinical findings. Patients over the age of 60 years were at greater risk of pulmonary complications following liver biopsy.

Dissolution of cholesterol gall stones using methyltertbutyl ether: a safe effective treatment

Methyltertbutyl ether (MTBE) administered by percutaneous transhepatic catheter rapidly dissolves radiolucent cholesterol gall bladder stones. However, complete dissolution and clearance of non-cholesterol debris is essential to prevent recurrence. In this study we analysed 25 consecutive patients with reference to efficacy and recurrence based on the presence or absence of non-cholesterol stone fragments after dissolution. Placement of the catheter was successful in 24 patients, one patient requiring cholecystectomy for bile peritonitis. MTBE was infused and aspirated continuously, four to six cycles per minute, resulting in rapid stone dissolution (median six hours; range 4-23 hours for solitary stones and median seven hours, range 4-30 hours for multiple stones). In 18 patients who had complete dissolution, four (22%) had recurrent stones within six to 18 months. Five patients had residual debris which failed to clear completely despite bile acid treatment. One patient with an incomplete rim of calcium in a large stone did not respond to MTBE treatment. A further patient required cholecystectomy for symptomatic recurrence. There were no serious side effects observed. MTBE treatment is a rapid, safe, and effective treatment for patients who refuse surgery or who for medical reasons cannot undergo cholecystectomy. The results of this study confirm that complete dissolution of all fragments is essential and may prevent recurrence.

Biochemical properties of the outer membrane of Treponema denticola

The outer membranes (OMs) from serovars a, b, and c of Treponema denticola, originally isolated from periodontal patients, were prepared. Dialysis of the OMs against 20 mM MgCl2 yielded the aggregable (A) and the nonaggregable (NA) moieties of the OMs. The absence of muramic acid, adenosine triphosphatase, hexokinase, and nucleic acid as well as electron microscopy indicated that the OM preparations were homogeneous. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the A and NA moieties of the OMs showed approximately 25 Coomassie brilliant blue R-250 stain-positive bands or 47 silver-stained polypeptides. The relative molecular masses ranged between 14 and 97 kDa. The electrophoretic polypeptide profiles of the A and NA moieties shared many similarities among serovars a, b, and c. However, they exhibited variation in the overall pattern, intensity, or location of the polypeptide stained zones. This was especially true for serovar b. Two-dimensional electrophoretic studies showed an excess of 100 silver-stained spots with isoelectric points of 4.6 to 7.0 and relative molecular masses in the 14- to 97-kDa range. The OMs contained simple proteins, glycoproteins, and lipoproteins. The NA moieties of the OMs contained 4 to 6, 10 to 12, and 4 to 6 glycopeptides as well as two, seven, and two lipoprotein bands for serovars a, b, and c, respectively. The A moieties of the OMs showed 7 to 9, 11 to 13 and 5 to 6 glycopeptides as well as four, five, and three lipoprotein bands for serovars a, b, and c, respectively. Lipopolysaccharide was detected in the OMs of the three serovars following removal of proteins with proteinase K, pronase and silver staining of sodium dodecyl sulfate-polyacrylamide gels, or removal of lipopolysaccharide from the OMs by hot phenol extraction. The 66- and 53-kDa bands were present in serovars b and c, while a band with a relative molecular mass of 45 kDa was present only in serovar c. Endotoxin-like activity was also shown in the OMs of the three serovars by the Limulus amebocyte clotting assay and the chick embryo lethality test. This is the first report on selected biochemical properties of the OM macromolecules of three known serovars of T. denticola.

Cytoplasmic proteins of Streptococcus mutans (serotype c) and their interaction with fluoride

The protein profile of the cytoplasmic proteins of Streptococcus mutans GS-5 was determined by two-dimensional gel electrophoresis. Use of this recently developed, high-resolution analytical tool showed in excess of 140 cytoplasmic proteins. The profile consisted of mostly acidic components with pI values between 3.70 and 5.30 and relative molecular weights mainly in the 13,000 to 90,000 range. With sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the proteins were resolved into 40 to 45 components. The binding of fluoride by the proteins reached a maximum value in 15 min, and it was linear with exogenous F- doses of up to 60 to 80 ppm per mg of protein (60 to 80 micrograms/g). The proteins bound 22 to 138 times more F- from assay mixtures containing 1 mM CaCl2 than from assay mixtures containing such ions as HgCl2, ZnCl2, CuCl2, MgCl2, MnCl2, or SnCl2. When NaF, SnF2, NH4F, CsF, (CH3)4NF, and Na2PO3F were used as sources of F- (adjusted to 10 ppm of F- in all cases), the proteins bound 2.1, 1.8, 1.6, 1.4, and 0.3 ppm of F- per mg of protein, respectively. Initial fractionation of the plasma proteins by preparative column isoelectric focusing indicated that proteins with pI values of 4.1 to 4.5 as well as those with pI values of 5.0 to 5.3 bound twice as much F- as did the proteins outside these pI values.

Binding of 18F by cell membranes and cell walls of Streptococcus mutans

The binding of 18F to isolated cell membranes and cell walls of Streptococcus mutans GS-5 or other bacteria was assayed. The attachment of 18F to these cell envelopes proceeded slowly and reached equilibrium within 60 min. 18F binding was stimulated by Ca2+ (1 mM). The binding of 18F to cellular components was dependent upon the pH, as well as the amount of 18F and dose of the binder employed. The binding of 18F by cell walls prepared from fluoride-sensitive and fluoride-resistant cells of S. salivarius and S. mutans did not differ significantly. The pretreatment of cell walls or cell membranes for 60 min at 30 degrees C with 1 mg of RNase, DNase, or trypsin per ml did not influence the binding of 18F by the walls and membranes of S. mutans GS-5. However, prior exposure of cell membranes to sodium dodecyl sulfate caused a significant reduction in the number of 18F atoms bound by the membranes. In saturated assay systems, cell membranes of S. mutans GS-5 bound 10(15) to 10(16) atoms of 18F per mg (dry weight), whereas cell walls from S. mutans GS-5, FA-1, and HS-6 or Actinomyces viscosus T14V and T14AV bound 10(12) to 10(13) atoms of 18F per mg (dry weight). 18F in this quantity (10(12) to 10(13) atoms) cannot be detected with the fluoride electrode. The data provide, for the first time, a demonstration of 18F binding by cell membranes and walls of oral flora.

Tuberculosis affecting a cadaveric renal allograft

Tuberculosis is one of the more serious infections complicating renal transplantation. Although the incidence appears to be low, a dose of prednisone greater than 10 mg daily has been associated with a more severe form of disease. A case of tuberculosis with renal allograft involvement is described with documented bacteriological and radiological involvement in which treatment was successful with anti-tuberculosis chemotherapy. Deterioration in renal function did not occur. The prophylaxis of patients undergoing transplantation with a history of tuberculosis and the features, diagnosis and treatment of tuberculosis affecting a renal allograft are discussed.