Recovery of kidney function after acute kidney disease-a multi-cohort analysis

BACKGROUND

There are no consensus definitions for evaluating kidney function recovery after acute kidney injury (AKI) and acute kidney disease (AKD), nor is it clear how recovery varies across populations and clinical subsets. We present a federated analysis of four population-based cohorts from Canada, Denmark and Scotland, 2011-18.

METHODS

We identified incident AKD defined by serum creatinine changes within 48 h, 7 days and 90 days based on KDIGO AKI and AKD criteria. Separately, we applied changes up to 365 days to address widely used e-alert implementations that extend beyond the KDIGO AKI and AKD timeframes. Kidney recovery was based on resolution of AKD and a subsequent creatinine measurement below 1.2× baseline. We evaluated transitions between non-recovery, recovery and death up to 1 year; within age, sex and comorbidity subgroups; between subset AKD definitions; and across cohorts.

RESULTS

There were 464 868 incident cases, median age 67-75 years. At 1 year, results were consistent across cohorts, with pooled mortalities for creatinine changes within 48 h, 7 days, 90 days and 365 days (and 95% confidence interval) of 40% (34%-45%), 40% (34%-46%), 37% (31%-42%) and 22% (16%-29%) respectively, and non-recovery of kidney function of 19% (15%-23%), 30% (24%-35%), 25% (21%-29%) and 37% (30%-43%), respectively. Recovery by 14 and 90 days was frequently not sustained at 1 year. Older males and those with heart failure or cancer were more likely to die than to experience sustained non-recovery, whereas the converse was true for younger females and those with diabetes.

CONCLUSION

Consistently across multiple cohorts, based on 1-year mortality and non-recovery, KDIGO AKD (up to 90 days) is at least prognostically similar to KDIGO AKI (7 days), and covers more people. Outcomes associated with AKD vary by age, sex and comorbidities such that older males are more likely to die, and younger females are less likely to recover.

The clinically extremely vulnerable to COVID: Identification and changes in healthcare while self-isolating (shielding) during the coronavirus pandemic

ObjectiveIn March 2020, Scottish government identified people clinically extremely vulnerable to COVID due to pre-existing health conditions. These people were advised to strictly self-isolate (shield) at home. We examined who was identified as clinically extremely vulnerable, how their healthcare changed during isolation, and whether this process exacerbated healthcare inequalities. ApproachWe linked all individuals on the shielding register in NHS Grampian to their in-patient and out-patient healthcare records from 2015 through 2020. We analysed the method of patients’ identification as clinically extremely vulnerable (via an algorithmic NHS record scan or designated ad hoc by their care-providers). We measured out-patient, in-patient, and emergency healthcare attendances, and compared use rates between two 3-month periods before and during the first strict isolation period. We evaluated changes in care use between those shielding and the general non-shielding population, and differences between shielding sub-populations (by clinical reason for shielding, age, sex, and socio-economic deprivation). ResultsThe shielding register included 16,092 people (3% of the population). 42% of people on the register were not identified by national healthcare record screening, including the majority of cancer and immunocompromised patients. People added to the register by their care-providers were more likely to be young and less economically-deprived. Shielders’ healthcare use decreased during isolation (rate compared to pre-isolation: 0.65 out-patient, 0.54 scheduled in-patient; 0.75 emergency in-patient; 0.71 A&E). However, people shielding had better maintained care than the non-shielding population (e.g. RR 2.9 for scheduled in-patient care). There were inequalities in whose scheduled care was maintained while shielding: younger people and those with cancer had significantly higher visit rates. However, there were no differences in care-preservation between men and women or between socioeconomic deprivation levels. ConclusionsThe reliance on emergency care while shielding indicates that, overall, continuity of care for existing conditions was not optimal. However, there was notable success in maintaining care for cancer. We suggest that integrating demographic and primary care data would improve identification of the clinically vulnerable and help equitably prioritise care.

Inequalities in children’s mental health prescribing and referrals for specialist mental health services

Objective1 in 8 young people in the United Kingdom are estimated to have a diagnosable mental health condition. Prevalence is increasing over time, many are untreated, and need is not evenly distributed across the population. We aimed to investigate trends in children’s mental health prescribing and referrals to specialist outpatient services. ApproachWe linked individual-level healthcare administrative records on community prescribing and referrals to outpatient Child and Adolescent Mental Health Services (CAMHS). The study cohort included all children aged 2 through 17 in the NHS Grampian Health Board region from 2015 to 2021 (average annual population circa 100,000) with a mental health prescription or CAMHS referral. We measured prevalence of mental health prescribing and referrals to CAMHS over time. We investigated demographic and socioeconomic differences, including comparison of rates by age, sex, and residential area deprivation. We also investigated socioeconomic and demographic differences in referral acceptance and rejection. ResultsPrescriptions for mental health drugs have risen 40%: from 5,000 per month in 2015 to 7,000 in 2021. 75% of prescriptions to primary schoolers are to boys, mostly for attention deficit hyperactivity disorder medications. Prescriptions to girls rise during secondary school, mostly for anti-depressants. Prescribing rates are 2.6-fold higher in the most versus least deprived areas. Referrals to CAMHS have risen 20% over the study period, and the proportion of referrals rejected has increased from 18% to 31% – leaving the number of children accepted to specialist care stable. Boys are referred twice as often at younger ages, while girls’ referrals spike during puberty. Since 2015, boys have been referred less and rejected more, with girls now making up 61% of those treated. Referral rates are two-fold higher in the most versus least deprived areas. ConclusionsBoth mental health prescribing and referrals to CAMHS have increased in this population, but the CAMHS service size remained fixed. Presentation and treatment patterns vary dramatically by age and sex, and socioeconomic inequalities are clear and persistent.

Self-Rated Health Inequalities in British Nurses

IntroductionImprovements in health in the UK are beginning to stall. Differences between the health of people living in the most and least deprived areas continue to grow. An excess in mortality, not explained by deprivation, has been observed in Scotland. Some of this difference likely results from limitations in deprivation measures. Objectives and ApproachWe seek to test whether Nurses experience health inequalities in Self-Rated Health comparable with the general population. We also aim to explore cross-national differences within the Nursing occupational group. We utilise data from Census-derived Longitudinal Studies in Scotland and England & Wales which are linked to an adjusted UK-consistent Multiple Deprivation measure. The databases can only be accessed securely, so an innovative method (eDatashield) has been used to conduct analysis as if the two were combined. Nurses are of interest as they are a large occupational group with potentially protective characteristics against inequalities including high health literacy and level of education. Socioeconomic homogeneity in this group may reduce the effect of confounding when exploring area-based deprivation measures. ResultsComparing Nurses to Non-Nurses we found they have systematically different and more homogenous characteristics. Nurses are; older, have a higher level of education, are more likely to be female, own their home, are less likely to live in deprived areas and they report better Self-Rated Health. However, inequalities persist. Comparing Self-Rated Health of Scottish with English & Welsh Nurses will determine whether an ‘excess’ in worse health outcomes exists and if so, whether the UK- consistent Deprivation Measure can account for this. Full results will be cleared for dissemination through disclosure control, prior to the conference. Conclusion / ImplicationsEven in a privileged group with characteristics which protect against poor health, inequalities remain. The methods applied here present an opportunity for improved cross-national comparison and address limitations in confounding when exploring inequalities based on area deprivation.

The response of the ozone layer to quadrupled CO2 concentrations

An accurate quantification of the stratospheric ozone feedback in climate change simulations requires knowledge of the ozone response to increased greenhouse gases. Here, we present an analysis of the ozone layer response to an abrupt quadrupling of CO2 concentrations in four chemistry-climate models. We show that increased CO2 levels lead to a decrease in ozone concentrations in the tropical lower stratosphere, and an increase over the high latitudes and throughout the upper stratosphere. This pattern is robust across all models examined here, although important inter-model differences in the magnitude of the response are found. As a result of the cancellation between upper and lower stratospheric ozone, the total column ozone response in the tropics is small, and appears to be model dependent. A substantial portion of the spread in the tropical column ozone is tied to inter-model spread in upwelling. The high latitude ozone response is strongly seasonally dependent, and shows increases peaking in late-winter and spring of each hemisphere, with prominent longitudinal asymmetries. The range of ozone responses to CO2 reported in this paper has the potential to induce significant radiative and dynamical effects on the simulated climate. Hence, these results highlight the need of using an ozone dataset consistent with CO2 forcing in models involved in climate sensitivity studies.

A comparative analysis of axillary nodal burden in ultrasound/biopsy positive axilla vs ultrasound negative sentinel lymph node biopsy positive axilla

BACKGROUND

Axillary Ultrasound (AUS) is now performed as a protocol in every newly diagnosed breast cancer in most European countries. It is an inexpensive and sensitive tool in hands of a trained operator. All AUS negative patients undergo Sentinel Lymph Node Biopsy (SLNB), while AUS positive patients bypass SLNB and undergo axillary nodal clearance (ANC) as a standard protocol. We wish to analyse these two groups to see if ANC can be foregone in these patients.

AIMS AND OBJECTIVES

To compare and analyse the axillary disease burden in early breast cancer patients, with positive axilla, detected by AUS+ Biopsy versus those patients with normal axillary ultrasound or negative axillary biopsy that underwent ANC due to positive SLNB.

MATERIAL AND METHODS

A retrospective review of all patients who underwent axillary lymph node clearance following histologically confirmed positive ultrasound (US) axilla (year 2009-2014) was performed and was compared with data collected for patients with USG negative but SLNB (OSNA- One Step Nucleic Acid Amplification) positive axilla.

RESULTS

Axillary clearances performed for positive US axilla yielded significantly more positive lymph nodes than SLNB/OSNA positive axilla (p = 0.00496). These patients also had larger primary tumours (median 33 mm versus 21 mm, p = 0.01242) of a higher grade. Almost half of the patients in AUS positive group (49%) had high axillary nodal burden (>4 LNs). This is in great contrast with AUS negative, SLNB/OSNA positive group where 82.7% of patients had <4 positive nodes with more than half patients (51.7%) having no further positive nodes in their final histopathology specimen.

CONCLUSIONS

ANC should be a standard protocol in AUS positive patients as they invariably have high axillary disease burden while ANC can be omitted in case of select AUS negative and SLNB patients. However, further studies with more subjects may be require to substantiate the findings.

A New Single-Item Sleep Quality Scale: Results of Psychometric Evaluation in Patients With Chronic Primary Insomnia and Depression

STUDY OBJECTIVES

A single-item sleep quality scale (SQS) was developed as a simple and practical sleep quality assessment and psychometrically evaluated.

METHODS

SQS measurement characteristics were evaluated using the Pittsburgh Sleep Quality Index (PSQI) and morning questionnaire-insomnia (MQI) according to prespecified analysis plans in separate clinical studies of patients with insomnia and depression. Patients with insomnia (n = 70) received 4 weeks' usual care with an FDA-approved hypnotic agent; patients with depression (n = 651) received 8 weeks' active or experimental therapy.

RESULTS

Concurrent criterion validity (correlation with measures of a similar construct) was demonstrated by strong (inverse) correlations between the SQS and MQI (week 1 Pearson correlation -.76) and PSQI (week 8 Goodman-Kruskal correlation -.92) sleep quality items in populations with insomnia and depression, respectively. In patients with depression, stronger correlations between the SQS and PSQI core sleep quality components versus other items supported convergent/divergent construct validity (similarity/dissimilarity to related/unrelated measures). Known-groups validity was evidenced by decreasing mean SQS scores across those who sleep normally, those borderline to having sleep problems, and those with problems sleeping. Test-retest reliability (intraclass correlation coefficient) was .62 during a 4-week period of sleep stability in patients with insomnia and .74 in stable patients with depression (1 week). Effect sizes (standardized response means) for change from baseline were 1.32 (week 1) and .67 (week 8) in populations with insomnia and depression, respectively. Mean SQS changes from baseline to week 8 convergently decreased across groups of patients with depression categorized by level of PSQI sleep quality improvement.

CONCLUSIONS

The SQS possesses favorable measurement characteristics relative to lengthier or more frequently administered sleep questionnaires in patients with insomnia and depression.

CLINICAL TRIAL REGISTRATION

Registry: ClincalTrials.gov, Title: Treatment of Patients With Major Depressive Disorder With MK0869, Identifier: NCT00034983, URL: https://clinicaltrials.gov/ct2/show/NCT00034983.

Health Inequalities in the British Nursing Workforce

BackgroundAverage health in the UK is improving, yet geographical inequalities in health persist. The relative difference between the least and most deprived is also growing. Recent policy interventions to reduce these inequalities have not been effective. MethodsThis work compares Self-Rated Health using the ONS LS and SLS linked to an adjusted UK-consistent small-area Deprivation measure. This study aims to compare Nurses to the general population to assess whether they also exhibit a social gradient in health. Using a single occupational group adjusts for potential confounders and tests whether characteristics of Nurses, such a good health literacy, degree education and above average income, are protective against inequalities. ResultsIn Scotland, Nurses are more likely to be older, female, homeowners who live in less deprived areas with better Self-Rated Health than Non-Nurses. We will test whether the social gradient in health is observed for this occupational group.Forthcoming results from cross-national analysis will be presented at conference following disclosure checks. ConclusionThe relationship between area deprivation and health may remain even in relatively privileged groups. Results from this study may inform recommendations to improve the effectiveness of policy aimed at improving population health and reducing socio-economic inequalities in health

Gastric Band Slippage: The Impact of a Change in Education and Band Filling

BACKGROUND

Gastric band slippage is a significant challenge in gastric band surgery and can result in poor weight loss, pain and dysphagia, often requiring re-operation. The Royal Berkshire Hospital is one of 49 UK centres performing bariatric surgery. We audited our band slippage rates.

METHODS

All patients undergoing gastric banding from February 2007 to December 2013 were included (follow-up until December 2014). Slip rate was calculated and compared to an audit standard (3.9 %). The impact of two interventions altering the method of band filling and post-operative dietary advice was studied.

RESULTS

Initial slippage rates were high (17 %). Rates decreased following the interventions: 8.5 % by July 2012 (p = 0.05); 2.7 % by December 2014 (p = 0.2).

CONCLUSIONS

Two simple, low-risk interventions have reduced complication rates in a high-risk population.

Na,K-adenosine triphosphatase alpha1-subunit predicts survival of renal clear cell carcinoma

PURPOSE

Na,K-adenosine triphosphatase, which is composed of a catalytic alpha-subunit and a regulatory beta-subunit, generates an electrochemical gradient across the plasma membrane. Previous studies demonstrated altered Na,K-adenosine triphosphatase subunit expression in renal clear cell carcinoma and an association of subunit levels with the prediction of recurrent bladder cancer. We determined the clinical association of protein expression patterns of the Na,K-adenosine triphosphatase alpha1 and beta1-subunits in renal clear cell carcinoma using tissue microarrays with linked clinicopathological data.

MATERIALS AND METHODS

The UCLA kidney cancer tissue microarray was used to investigate the protein expression of Na,K-adenosine triphosphatase alpha1 and beta1-subunits by immunohistochemistry in 342 patients with renal clear cell carcinoma who were treated with radical nephrectomy. Of these patients clinical outcomes studies were performed in 317. The resultant expression reactivity was correlated with clinicopathological variables.

RESULTS

We found that the alpha1-subunit was a significant and independent predictor of disease specific death from renal clear cell carcinoma on multivariate Cox proportional hazards analysis that included established prognostic factors Eastern Cooperative Oncology Group performance status, pT status, metastasis status and tumor grade. Significance was found when examining all patients with clear cell renal cell carcinoma as well as patient substrata with low or high grade tumors and localized or metastatic disease, suggesting that the Na,K-adenosine triphosphatase alpha1-subunit could be used as a new prognosticator for disease specific death from renal clear cell carcinoma.

CONCLUSIONS

These results suggest that Na,K-adenosine triphosphatase alpha1-subunit expression patterns may be a useful clinical prognosticator for renal clear cell carcinoma. The Na,K-adenosine triphosphatase beta1-subunit was not found to be a useful prognosticator in this setting.

Lack of efficacy of the substance p (neurokinin1 receptor) antagonist aprepitant in the treatment of major depressive disorder

BACKGROUND

An early clinical trial suggested that the substance P (neurokinin(1) receptor) antagonist, aprepitant, might provide a unique mechanism of antidepressant activity. Phase III trials were conducted to confirm these findings.

METHODS

Five 8-week, randomized, double-blind, parallel-groups, placebo-controlled, multicenter trials in outpatients with Major Depressive Disorder were performed. Aprepitant 160 mg and placebo were included in all trials. Aprepitant 80 mg and paroxetine 20 mg (active comparator) were included in three trials. Approximately 150 patients were enrolled per treatment group in each trial. The primary end point was the mean change-from-baseline of the first 17 items of the Hamilton Rating Scale for Depression (HAM-D(17)) score at 8 weeks. A positron emission tomography (PET) study was also performed in normal subjects to determine the relationship between neurokinin(1) receptor occupancy and aprepitant plasma concentrations in dosing regimens relevant to the trials.

RESULTS

No statistically significant differences from placebo on the HAM-D(17) were observed at week 8 for either dose of aprepitant in any of the trials, whereas paroxetine 20 mg was significantly (p <or= .05) more effective than placebo at week 8 in each of the three trials in which it was included. Results from the PET study indicated that the aprepitant dosing regimens provided continuously high levels of neurokinin(1) receptor blockade over 8 weeks.

CONCLUSIONS

Because the methodology employed confirmed the antidepressant efficacy of paroxetine, the absence of an effect for aprepitant indicates that it was not an effective treatment for depression. The concept of neurokinin(1) receptor antagonism as an antidepressant mechanism was not supported.

An improved methodology for modeling neurobehavioral late-effects of radiotherapy in pediatric brain tumors

BACKGROUND

Technical advances in radiation oncology provide new opportunities to study neurobehavioral outcomes of radiation therapy (RT) in children treated for brain tumors.

METHODS

In this study, we describe an approach to modeling late-effects using integral biologically effective dose (IBED) combined with improved measurement of critical neuropsychological functions.

RESULTS

IBED was found to provide more differentiated information about dose distribution than prescribed dose in five subjects treated for brain tumors. Furthermore, IBED was more closely related than was prescribed dose to specific changes in Attention 2-3 years post-RT.

CONCLUSIONS

Results support the feasibility of this methodology as well as promising preliminary evidence of the relationship of IBED to the construct of Attention. Improved modeling could lead to more refined radiation therapy protocols that preserve critical neuropsychological functions and also provide new insights into the treatment of neurobehavioral sequelae.

Cerebral MR imaging in uninfected children born to HIV-seropositive mothers and perinatally exposed to zidovudine

BACKGROUND AND PURPOSE

Mitochondrial dysfunction has been reported in HIV-negative children perinatally exposed to zidovudine, a drug often used in HIV-seropositive mothers during pregnancy. The purpose of this study was to determine the incidence of cerebral MR imaging findings in HIV-uninfected children exposed to zidovudine who present with unexplained neurologic symptoms.

METHODS

Two expert groups conducted a systematic, retrospective review of all cerebral MR images available in a multicentric, nationwide French prospective cohort of children born to HIV-seropositive mothers to identify imaging abnormalities. Experts were blinded to each others' interpretations, to the children's neurologic symptoms, and to laboratory evidence of mitochondrial dysfunction. The incidence of abnormalities was determined and compared with the neurologic presentation and laboratory evidence of mitochondrial dysfunction.

RESULTS

MR images from 49 HIV-uninfected children (mean age, 26 months) were available for study. All children were perinatally exposed to zidovudine. Twenty-two had probable or established mitochondrial dysfunction according to their symptoms and laboratory data. Twenty-seven children without mitochondrial dysfunction presented with unexplained neurologic symptoms (n = 14) or nonneurologic symptoms (n = 7), and six were asymptomatic. Sixteen of 22 MR images in children with mitochondriopathy were considered abnormal in both independent analyses. Diffuse hyperintensity in the supratentorial white matter (n = 9) and in the tegmentum pons (n = 9) were the most frequent anomalies. Imaging abnormalities were often multifocal (n = 10) and sometimes associated with necrotic areas (n = 3) and volume loss (n = 8). Although 19 of 27 MR images of children without mitochondrial dysfunction were mainly normal, abnormal images were observed in five of 14 children with unexplained neurologic symptoms and in three of six asymptomatic children.

CONCLUSION

Images observed in children with antiretroviral-induced mitochondrial dysfunction are similar to those observed in congenital mitochondrial diseases. These images were also observed in symptomatic or asymptomatic children without evidence of systemic mitochondrial dysfunction.

Relationship of structural magnetic resonance imaging, magnetic resonance perfusion, and other disease factors to neuropsychological outcome in sickle cell disease

OBJECTIVE

To investigate the relationship between neuropsychological functioning and radiographic findings in children with sickle cell disease (SCD) with no history of clinical neurological events.

METHODS

Thirty-one patients with SCD randomly selected from a regional treatment center underwent neuropsychological and disease severity assessments. Of these, 22 also had structural magnetic resonance imaging and magnetic resonance perfusion studies performed.

RESULTS

Forty-five percent of the imaged subgroup showed imaging abnormalities that were found to be correlated with disease severity but not neuropsychological level of performance indices. A significant relationship, however, was found between imaging abnormalities and increased variability in neuropsychological performance.

CONCLUSIONS

These results corroborate the high rate of rheologic and vascular pathology in SCD and underscore the importance of representing neuropsychological functioning in multiple ways.

Multi-level adaptive segmentation of multi-parameter MR brain images

MR brain image segmentation into several tissue classes is of significant interest to visualize and quantify individual anatomical structures. Traditionally, the segmentation is performed manually in a clinical environment that is operator dependent and may be difficult to reproduce. Though several algorithms have been investigated in the literature for computerized automatic segmentation of MR brain images, they are usually targeted to classify image into a limited number of classes such as white matter, gray matter, cerebrospinal fluid and specific lesions. We present a novel model-based method for the automatic segmentation and classification of multi-parameter MR brain images into a larger number of tissue classes of interest. Our model employs 15 brain tissue classes instead of the commonly used set of four classes, which were of clinical interest to neuroradiologists for following-up with patients suffering from cerebrovascular deficiency (CVD) and/or stroke. The model approximates the spatial distribution of tissue classes by a Gauss Markov random field and uses the maximum likelihood method to estimate the class probabilities and transitional probabilities for each pixel of the image. Multi-parameter MR brain images with T(1), T(2), proton density, Gd+T(1), and perfusion imaging were used in segmentation and classification. In the development of the segmentation model, true class-membership of measured parameters was determined from manual segmentation of a set of normal and pathologic brain images by a team of neuroradiologists. The manual segmentation was performed using a human-computer interface specifically designed for pixel-by-pixel segmentation of brain images. The registration of corresponding images from different brains was accomplished using an elastic transformation. The presented segmentation method uses the multi-parameter model in adaptive segmentation of brain images on a pixel-by-pixel basis. The method was evaluated on a set of multi-parameter MR brain images of a twelve-year old patient 48h after suffering a stroke. The results of classification as compared to the manual segmentation of the same data show the efficacy and accuracy of the presented methods as well as its capability to create and learn new tissue classes.

A 56-year-old woman with recurrent episodes of weakness and hypoglycemia

The differential diagnosis for a 56-year-old woman with recurrent episodes of weakness and hypoglycemia is discussed in the setting of a clinicopathological conference at the Louisiana State University Medical Center in Shreveport, Louisiana. The diagnostic approach to the workup of a patient presenting with hypoglycemia is outlined.

Anti-T cell receptor monoclonal antibody prolongs transgene expression following adenovirus-mediated in vivo gene transfer to mouse synovium

There are no cures for rheumatoid arthritis (RA) or other inflammatory autoimmune arthropathies. Gene transfer to the synovium would allow administration of anti-inflammatory gene products directly to the articular space where they could exert a local down-regulatory effect on the autoimmune process. Several well-characterized murine models of arthritis closely resemble RA immunologically, genetically, and histopathologically. To determine whether the mouse could serve as a model for gene transfer to the synovium, a methodology was developed to reproducibly inject a 5-microliter volume into the articular space of the mouse knee. Using this approach, Av1LacZ4, an E1a-E3-deleted adenoviral (Ad5) vector expressing the lacZ transgene, was delivered intra-articularly (5 x 10(8) pfu). lacZ expression was observed in the articular synovium for at least 14 days. Biochemical quantitation demonstrated a gradual loss of transgene expression, associated with an early, predominantly neutrophilic, inflammatory response that progressed to a lymphocytic infiltrate, followed by gradual resolution over a 3-week period. Pretreatment with the anti-TCR monoclonal antibody (mAb) H57 resulted in a significant reduction in lymphocytic infiltration and a prolongation of transgene expression. These data demonstrate that transgenes can be delivered to the mouse knee joint space, affording a powerful tool to test the potential of gene therapy as a therapeutic modality for RA. As in other systems, the immune response against recombinant adenoviral vectors may limit the extent and duration of gene expression in the synovium. Anti-T cell mAbs may be useful in inhibiting this immune response.

Paroxysmal supraventricular tachycardia of unusual etiology: a case report

Paroxysmal supraventricular tachycardia (PSVT) is a serious cardiac disturbance that can arise spontaneously or be initiated by noncardiac mechanisms. An occurrence of this dysrhythmia in a 55-year-old male undergoing monitored anesthesia care for excision of a subxiphoid subcutaneous mass is reported. The unusual cause of this patient's ectopy is discussed. The nature and treatment of PSVT are reviewed, as are the clinical considerations for anesthetists who encounter a comparable clinical problem.

Radiographic characteristics of skull fractures resulting from child abuse

Radiographic characteristics of skull fractures in 39 cases of documented child abuse were compared with skull fractures in 95 cases of accidental injury to determine if differential features could be identified. All children were less than 2 years old. Emergency room and hospital records for these patients were also reviewed. The results of this study show that clinical features did not provide any clues as to whether the children had been injured by abuse or by accident. However, it was found that multiple fractures, bilateral fractures, and fractures crossing sutures occurred significantly more often in abuse cases than in accidental injury. When such fractures are present, abuse should be suspected.

Postasphyxial encephalopathy in full-term infants: ultrasound diagnosis

Abnormal cranial ultrasound findings are described in 18 infants with severe asphyxia. The examinations performed within the first 7 days after the asphyxial episode frequently showed obliteration of the ventricles and extra-axial fluid spaces with mildly increased cerebral echogenicity, presumably representing cerebral edema. Others showed diffusely abnormal parenchymal echogenicity with normal ventricles and sulci. Ultrasound findings seen after the first week of life included increased size of the ventricles and extra-axial fluid, the result of cerebral atrophy. The sensitivity, specificity, and accuracy of both early and late abnormal ultrasonograms were calculated for predicting an abnormal neurological outcome. While the sensitivity of the abnormal early (performed within 7 days of birth) ultrasonogram was relatively low (46%), the sensitivity of an abnormal late (performed after 7 days) ultrasonogram was high (86%). The specificity for both abnormal early and late ultrasound was 100%. These findings suggest that cranial ultrasonography can be used as a screening procedure to provide information about the neurologic outcome to clinicians caring for these infants.

Determination of ammonia inhibition in fabric impregnated with antimicrobials

A new method is described for determining the presence or absence of ammonia produced by urealytic microorganisms, using fabric which has been treated with an antimicrobial. Circular disks of fabric treated with various concentrations of an antimicrobial are placed in the bottoms of snap-on lid petri dishes. Nutrient medium containing urea, an indicator, and a dilution of an overnight culture of Proteus mirabilis is applied to the fabric disks. The lids are snapped on and the dishes are incubated at 37 degrees C. By examination of the fabric disks at regular intervals of time for a color change from white to red, one may determine whether the concentration of antimicrobial in the fabric is sufficient to inhibit the production of ammonia by a urealytic microorganism.

Determination of Ammonia Inhibition in Fabric Impregnated with Antimicrobials

A new method is described for determining the presence or absence of ammonia produced by urealytic microorganisms, using fabric which has been treated with an antimicrobial. Circular disks of fabric treated with various concentrations of an antimicrobial are placed in the bottoms of snap-on lid petri dishes. Nutrient medium containing urea, an indicator, and a dilution of an overnight culture of Proteus mirabilis is applied to the fabric disks. The lids are snapped on and the dishes are incubated at 37°C. By examination of the fabric disks at regular intervals of time for a color change from white to red, one may determine whether the concentration of antimicrobial in the fabric is sufficient to inhibit the production of ammonia by a urealytic microorganism.

Simplified Modifications of the AOAC Method for Bacteriostatic Activity of Laundry Additives

Modifications of the AOAC bacteriostatic activity of laundry additives method are described, which render it more economical and less time consuming. The arbitrary use of a minimum of 18—20 edges showing clear zones of inhibition of a test organism, when 5 fabric patches 1" square are used, is liable to misinterpretation, since faulty methods of introducing germicidal substances into fabric in the final rinse during laundering result in incomplete dispersion and uneven impregnation. Therefore, absence of a zone along more than 2 edges may indicate faulty impregnation rather than the degree of bacteriostatic activity. In the modified procedure, 5 circular fabric disks from samples submitted by laundries were used for each test. They were immersed in melted, seeded nutrient agar in 1 large Petri dish and incubated at 5 and 37°C. Clear zones completely around all 5 circumferences were chosen as the criteria for bacteriostatic activity. If all 5 disks, taken from different areas of the test sample, do not show complete inhibition, impregnation of the bacteriostat is not uniform.

Infant responses to impending collision: optical and real

Twenty-four infants ranging in age from 2 to 11 weeks responded to symmetrically expanding shadows, which optically specify an approaching object, with an integrated avoidance response and upset. This response did not occur for asymmetrically expanding shadows nor for contracting shadows that specify an object on a miss path and a receding object. The response was observed in all the infants regardless of age, and the addition of kinetic depth information to the displays did not increase the intensity or likelihood of the response. In a second experiment, seven infants defensively reacted to the approach of a real object except when it was on a miss path.