Recommended Resting-State fMRI Acquisition and Preprocessing Steps for Preoperative Mapping of Language and Motor and Visual Areas in Adult and Pediatric Patients with Brain Tumors and Epilepsy

Resting-state (rs) fMRI has been shown to be useful for preoperative mapping of functional areas in patients with brain tumors and epilepsy. However, its lack of standardization limits its widespread use and hinders multicenter collaboration. The American Society of Functional Neuroradiology, American Society of Pediatric Neuroradiology, and the American Society of Neuroradiology Functional and Diffusion MR Imaging Study Group recommend specific rs-fMRI acquisition approaches and preprocessing steps that will further support rs-fMRI for future clinical use. A task force with expertise in fMRI from multiple institutions provided recommendations on the rs-fMRI steps needed for mapping of language, motor, and visual areas in adult and pediatric patients with brain tumor and epilepsy. These were based on an extensive literature review and expert consensus.Following rs-fMRI acquisition parameters are recommended: minimum 6-minute acquisition time; scan with eyes open with fixation; obtain rs-fMRI before both task-based fMRI and contrast administration; temporal resolution of ≤2 seconds; scanner field strength of 3T or higher. The following rs-fMRI preprocessing steps and parameters are recommended: motion correction (seed-based correlation analysis [SBC], independent component analysis [ICA]); despiking (SBC); volume censoring (SBC, ICA); nuisance regression of CSF and white matter signals (SBC); head motion regression (SBC, ICA); bandpass filtering (SBC, ICA); and spatial smoothing with a kernel size that is twice the effective voxel size (SBC, ICA).The consensus recommendations put forth for rs-fMRI acquisition and preprocessing steps will aid in standardization of practice and guide rs-fMRI program development across institutions. Standardized rs-fMRI protocols and processing pipelines are essential for multicenter trials and to implement rs-fMRI as part of standard clinical practice.

Comprehensive Update and Review of Clinical and Imaging Features of SMART Syndrome

Stroke-like migraine attacks after radiation therapy (SMART) syndrome is a delayed complication of cranial irradiation, with subacute onset of stroke-like symptoms including seizures, visual disturbance, speech impairment, unilateral hemianopsia, facial droop, and aphasia, often associated with migraine-type headache. The diagnostic criteria were initially proposed in 2006. However, the diagnosis of SMART syndrome is challenging because clinical symptoms and imaging features of SMART syndrome are indeterminate and overlap with tumor recurrence and other neurologic diseases, which may result in inappropriate clinical management and unnecessary invasive diagnostic procedures. Recently, various imaging features and treatment recommendations for SMART syndrome have been reported. Radiologists and clinicians should be familiar with updates on clinical and imaging features of this delayed radiation complication because recognition of this entity can facilitate proper clinical work-up and management. This review provides current updates and a comprehensive overview of the clinical and imaging features of SMART syndrome.

1251 FRAILTY PREVALENCE AND RISK OF SARCOPENIA IN OLDER HEART FAILURE (HF) INPATIENTS

Introduction

Both frailty and HF are common in the elderly population. Elderly HF patients have an increased risk of frailty and elderly frail patients are at a higher risk of developing HF. Frailty is an independent predictor of mortality in cardiovascular disease. Sarcopenia (defined as decreased muscle mass and muscle strength and/or performance) is also prevalent in HF patients and may progress to cardiac cachexia. HF may induce sarcopenia and sarcopenia may contribute to the poor prognosis of HF.

Aims

Methods

A cross-sectional, retrospective analysis of consecutive patients, 60 years and over, admitted with HF to a UK hospital. Data was manually extracted from anonymized electronic records. The Rockwood Clinical Frailty Scale (CFS) was used for assessment for frailty and the SARC-F tool was used for screening for sarcopenia. Patients with medical history of HF but did not present with decompensated HF were excluded. Also, patients with incomplete data were excluded. The IBM SPSS 28 statistical package was used for statistical analysis. Descriptive statistics and risk estimates were calculated.

Results

163 patients were analysed; 82 males and 81 females. The mean age was 81.4 years (SD 9.69). 71.5 % of patients were frail while 28.5 % were non-frail. The risk of sarcopenia was 10.9 times greater in the frail than in the non-frail patients (OR = 10.9; 95% C.I 4.85 – 24.67). There was a lower risk of sarcopenia in male patients than in the female patients (OR =0.45; 95% C.I 0.22 – 0.94).

Conclusions

Frailty is prevalent in older heart failure inpatients. It significantly increases the risk of sarcopenia in these patients. Women are at higher risk of sarcopenia than men. More research is needed into frailty and sarcopenia in.

1242 CO-MORBIDITY, FRAILTY AND EJECTION FRACTION IN OLDER HEART FAILURE INPATIENTS

Introduction

Co-morbidities and frailty are common in older heart failure patients. The aim of this study is to explore the relationship between co-morbidity, frailty and ejection fraction (EF) in older heart failure inpatients

Methods

A cross-sectional, observational, retrospective analysis of consecutive patients aged 60 years and over who were admitted with heart failure in a UK hospital. Patients with incomplete data were excluded. The Carlson’s comorbidity index (CCI) was used to compute comorbidity and the Rockwood Clinical Frailty Scale (CFS) was used to measure frailty. The EF was calculated as the midpoint of the ranges measured by echocardiography. IBM SPSS 28 software was used for statistical analysis. Descriptive statistics were used to measure baseline characteristics and Pearson’s correlation coefficient and linear regression were used to calculate correlation.

Results and discussion

101 patients were analysed; 48 males and 53 females. Mean age was 81.2 years(SD 9.98). Mean CCI was 6.97(SD 1.63) and mean CFS was 5.09(SD 1.14). There was statistically significant positive correlation between CCI and CFS (r= 0.232; p= .01). There was statistically significant inverse correlation between CCI and EF (r= -.277; p=. 005). When taking into account the level of frailty the correlation between CCI and EF was much stronger in non-frail than in frail patients (r= -.612; p=. 035 and r= -.216; p= .047 respectively). There was no correlation between CFS and EF (r= .095; p=.26). This was not surprising as HFpEF is the most common type of HF in the elderly. HFpEF patients are more likely to have more comorbidities and to be more frail compared to HFrEF patients.

Conclusion

There was a positive correlation between multi-morbidity and frailty in older inpatients admitted with heart failure. There was statistically significant inverse correlation between CCI and ejection fraction but there was no correlation between frailty and ejection.

Oxidative Stress and Cardiovascular Risk in Type 1 Diabetes Mellitus: Insights From the DCCT/EDIC Study

Background

Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus.

Methods and Results

A random subcohort of 349 participants was selected from the DCCT / EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT , and 1 to 2 years post‐ DCCT ( EDIC years 1 and 2) were measured for markers of oxidative stress, including plasma myeloperoxidase, paraoxonase activity, urinary F 2α isoprostanes, and its metabolite, 2,3 dinor‐8 iso prostaglandin F 2α . Following adjustment for glycated hemoblobin and weighting the observations inversely proportional to the sampling selection probabilities, higher paraoxonase activity, reflective of antioxidant activity, and 2,3 dinor‐8 iso prostaglandin F 2α , an oxidative marker, were significantly associated with lower risk of cardiovascular disease (−4.5% risk for 10% higher paraoxonase, P <0.003; −5.3% risk for 10% higher 2,3 dinor‐8 iso prostaglandin F 2α , P =0.0092). In contrast, the oxidative markers myeloperoxidase and F 2α isoprostanes were not significantly associated with cardiovascular disease after adjustment for glycated hemoblobin. There were no significant differences between DCCT intensive and conventional treatment groups in the change in all biomarkers across time segments.

Conclusions

Heightened antioxidant activity (rather than diminished oxidative stress markers) is associated with lower cardiovascular disease risk in type 1 diabetes mellitus, but these biomarkers did not change over time with intensification of glycemic control.

Clinical Trial Registration

URL : https://www.clinicaltrials.gov . Unique identifiers: NCT 00360815 and NCT 00360893.

Retrospective assessment of the validity and use of the community balance and mobility scale among individuals with subacute spinal cord injury

STUDY DESIGN

This is a retrospective chart review.

OBJECTIVES

The objective of this study was to evaluate the convergent validity, internal consistency and use of the Community Balance & Mobility Scale (CB&M) in individuals with incomplete spinal cord injury (iSCI) during inpatient rehabilitation.

SETTING

This study was conducted in an SCI rehabilitation center in Canada.

METHODS

Inpatient charts from January 2009 to October 2015 were screened. A chart was excluded if the inpatient was aged >65 years, did not complete a CB&M and/or had a comorbid condition. Demographics, CB&M score and injury-related characteristics were extracted. Berg Balance Scale (BBS), Six-Minute Walk Test (6 MWT) and Ten-Meter Walk Test (10 mWT) scores were obtained if completed within 1 week of the CB&M. χ²-Tests were used to identify CB&M items that were uniformly distributed, implying good discrimination between individuals. Convergent validity was assessed by correlating (Pearson's r) CB&M scores with BBS, 6 MWT and 10 mWT scores. Internal consistency (Cronbach's α) was evaluated.

RESULTS

Thirty inpatients were included (23 male, 38.3±15.3 years old, three AIS C, 26 AIS D, C1-L4, 16 traumatic). BBS scores were ⩾51/56; however, CB&M scores showed a wider range (27-82/96). Unilateral Stance, Tandem Walking, Lateral Foot Scooting, Forward to Backward Walking and Descending Stairs showed uniform distributions. Scores on the CB&M correlated strongly with scores on the 6 MWT (r=0.72, P<0.001) and moderately strongly with 10 mWT and BBS scores (r=0.47-0.59, P=0.004-0.013). Cronbach's α=0.87.

CONCLUSIONS

The CB&M is a valid measure in high-functioning individuals with iSCI. Prospective studies are required to further evaluate the psychometric properties of the CB&M as a measure of high-level balance for SCI.

Role of tacrolimus combination therapy with mycophenolate mofetil in the prevention of organ rejection in kidney transplant patients

Introduction:

Several new medications are now available for immunosuppression in the kidney transplant field. Tacrolimus and mycophenolate mofetil were first introduced for immunosuppression in renal transplantation in the mid 1990s. Since then, the combination of tacrolimus and mycophenolate mofetil has been evaluated in numerous clinical trials. The outcomes of these trials have varied due to differences in induction and/or maintenance therapy, drug dosing and monitoring protocols, and study design. The aim of this review is to analyze the literature critically and to provide an overview of tacrolimus and mycophenolate mofetil combination therapy in renal transplantation.

Extraskeletal ossifying chondroma in Hoffa's fat pad: an unusual cause of anterior knee pain

Hoffa's disease is an obscure cause of anterior knee pain. A misconception about its rarity is very common among clinicians, and hence it is often misdiagnosed and treated as meniscal pathology. Increased awareness is required to diagnose and treat the condition appropriately. These diagnostic uncertainties commonly result in increased patient morbidity and mismanagement. In spite of a widely-accepted common occurrence of Hoffa's disease, ossification of the Hoffa's fat pad is seldom reported. We report a giant extraskeletal ossifying chondroma in a 55-year-old man, presented as chronic knee pain and successfully treated by excision. The anatomy, pathology, histology, radiological features and management of the disease are described, to increase awareness in the orthopaedic community of this common, interesting but rarely discussed condition.

Impact of recipient obesity on living donor kidney transplant outcomes: a single-center experience

The number of overweight and obese patients undergoing renal transplantation has drastically increased in the last two decades. Studies on graft survival and complication rates of these obese patients have had conflicting results, with some reporting a significant risk and others reporting relatively good outcomes. We examined 1-year outcomes in obese and nonobese patients who underwent living donor transplants at our transplant program, a slightly different approach than prior studies of deceased donor transplants into patients with high body mass index (BMI). The mean serum creatinine clearance by the modified MDRD equation at the end of 1 year in the nonobese group was 58.9 mL/min whereas the mean creatinine clearance in the obese group was 48.9 mL/min (P = .09). The length of stay, incidence of delayed graft function, and 1-year graft survival did not differ between the obese and nonobese groups. The results of this single-center experience with living donor transplant into obese subjects suggest no differences in outcomes with regard to surgical or wound complications, delayed graft function, or serum creatinine at 1 year.

Richter's transformation of chronic lymphocytic leukemia

Transformation of CLL into a large cell lymphoma has an incidence of 3-5%. We have studied 101 cases of CLL treated with fludarabine over a 10-year period (1990-2000) and observed a 12% incidence of transformation. In six of 12 patients, transformation was documented within 4 months following treatment with fludarabine. Pathological material, available in nine cases, was investigated for latent EBV by staining for LMP-1 by immunohistochemistry and EBERs-1 and 2 by in situ hybridisation. LMP-1 and EBERs were demonstrated in three of the nine samples. In two cases there was a different pattern of immunoglobulin gene rearrangement in the transformed cells assessed by PCR (FR3 fragment) compared to the original CLL clone. One of these two cases showed evidence of latent EBV. The other seven cases, of which two were EBV positive, showed identical pattern of Ig gene rearrangement in both the CLL and the transformed cells. We suggest that the relatively high incidence of transformation in this series may be due to immunosuppression mainly related to fludarabine, although other agents and prior therapies may have also contributed.

Misleading acute hypercalcemia due to hyperlipidemia: a method-dependent error

OBJECTIVE

To report a case of artifactual hypercalcemia in a patient with hyperlipidemia.

METHODS

We present clinical data and laboratory findings in a 33-year-old woman with generalized fatigue, a recent 5-kg weight loss, and a papular rash on the extremities as well as a history of diabetes and hypertension.

RESULTS

Physical examination revealed an obese patient with eruptive xanthomas and lipemia retinalis. Laboratory tests showed hyperlipidemia, hypercalcemia (serum calcium measured by spectrophotometry), anemia, hyperproteinemia, hyperuricemia, and hyperbilirubinemia. After 4 days of a low-fat, low-cholesterol diet and gemfibrozil therapy, the serum triglyceride level decreased, and the serum calcium concentration returned to normal.

CONCLUSION

In patients with hypercalcemia without an obvious cause, a spurious measurement should be considered.

A validated HPLC assay for simultaneous analysis of salmon calcitonin and duck ovomucoid

A highly sensitive and selective analytical HPLC method is reported for the simultaneous measurement of salmon calcitonin (sCT) and its enzyme inhibitor, duck ovomucoid (dOVM). The method used a reversed phase C-18 column (4.6 x 250 mm, 5 microm) at room temperature. The elution was achieved using a gradient technique (20-35% B for 10 min, 35-37% B from 10th to 20th min and 37-20% B from 20th to 25th min). The mobile phase used was 0.05% v/v trifluoroacetic acid (TFA) in water and 0.05% v/v TFA in acetonitrile with a flow rate of 1 ml/min. Detection was carried out by UV spectrophotometry at 210 nm. sCT and dOVM were eluted at 7.8 and 15.4 min respectively, free from any interfering endogenous peaks during a run time of 25 min. Linear relationships were observed between the detector response and the concentrations of the analytes (10-100 microg/ml for CT (r2 = 0.996) and 10-100 microg/ml for the dOVM (r2 = 0.999)). The assay was found to be highly selective and sensitive due to the absence of any interfering peaks. The lower C.V. and % error values of the assay indicates that the assay could accurately and precisely quantitate both sCT and dOVM in the examined concentration range. This method can be usedfor the simultaneous quantitative analysis of sCT and dOVM.

Immunohistochemical markers in the differentiation of thymic and pulmonary neoplasms

AIMS

The histopathological features of some thymic neoplasms overlap with those of pulmonary squamous and large-cell undifferentiated carcinomas, and identification of the primary site may be difficult on routine staining. We have assessed a panel of antibodies that may help to distinguish between neoplasms from these two sites.

METHODS AND RESULTS

Antibodies identifying cytokeratin 7 (CK7), CD5, CD10, CD1a and thyroid transcription factor-1 (TTF-1) were applied to a series of 20 thymic neoplasms (thymic carcinomas, atypical thymomas and thymomas), 10 primary squamous cell carcinomas of the lung and 10 large-cell undifferentiated carcinomas of the lung. Staining for TTF-1 was positive in 3/10 large-cell undifferentiated carcinomas, but negative in all other tumours. CD5 showed strong membranous staining in 3/6 thymic carcinomas and 1/14 thymomas, but only focal staining in 1/20 pulmonary carcinomas. CD1a was consistently positive in thymic lymphocytes in both typical and atypical thymomas, but only focally in 1/6 thymic carcinomas. CD1a stained dendritic cells in 7/20 pulmonary carcinomas, but did not stain lymphocytes. Staining for CK7 and CD10 did not aid in differentiating between a pulmonary or thymic origin of the tumour.

CONCLUSION

Staining for TTF-1, CD5 and CD1a have potential use in distinguishing between pulmonary and thymic neoplasms.

Calcitonin is a prostate epithelium-derived growth stimulatory peptide

Locally secreted growth factors and neuropeptides may play an important role in sustaining the growth of hormone-independent prostate cancer. Our previous studies have shown that calcitonin-like immunoreactive peptide (CTI) is secreted by primary prostate cells in culture, and its secretion from malignant prostate cells is significantly higher than benign cells. Exogenously added calcitonin (CT) induces DNA synthesis in serum-starved prostate cancer LNCaP and PC-3M cells. Present studies extended these findings by cloning cDNAs for CT and CT receptor (CT-R) from prostate cancer cells and studying the expression of CT and CT-R mRNA in prostate cancer cell lines and primary prostate tumor specimens. The results have shown that PC-3 cells expressed CT, and not CT-R, mRNA, whereas CT-R, but not CT, mRNA was expressed by LNCaP cells. Conditioned media from PC-3 cells induced DNA synthesis of LNCaP cells, and this mitogenic response was abolished by anti-CT serum. Highly aggressive PC-3M cells co-expressed CT and CT-R mRNAs. CT also induced a twofold increase in DNA synthesis of primary prostate cells and anti-CT serum caused a 56% decline. In-situ hybridization histochemistry of archival prostate specimens has selectively localized CT and CT-R mRNA in basal epithelium of benign and low grade PC specimens, and these mRNAs were not detected in either luminal epithelium or stroma. In contrast, CT and CT-R mRNA were detected throughout the luminal epithelium of moderate and high-grade PC specimens. Most epithelial cells of low and moderately differentiated tumors expressed either CT or CT-R mRNA, suggesting that CT may serve as a paracrine factor. In contrast, CT and CT-R mRNAs were co-expressed by most tumor cells in advanced PC specimens. The cells expressing CT-R mRNA in primary tumors also co-expressed PCNA. These results, when combined with mitogenic actions of CT on primary prostate cells as well as PC cell lines, strongly support the role for CT in sustaining the growth of cancer cells.

Identification of a gene responsible for familial Wolff-Parkinson-White syndrome

BACKGROUND

The Wolff-Parkinson-White syndrome, with a prevalence in Western countries of 1.5 to 3.1 per 1000 persons, causes considerable morbidity and may cause sudden death. We identified two families in which the Wolff-Parkinson-White syndrome segregated as an autosomal dominant disorder.

METHODS

We studied 70 members of the two families (57 in Family 1 and 13 in Family 2). The subjects underwent 12-lead electrocardiography and two-dimensional echocardiography. Genotyping mapped the gene responsible to 7q34-q36, a locus previously identified to be responsible for an inherited form of Wolff-Parkinson-White syndrome. Candidate genes were identified, sequenced, and analyzed in normal and affected family members to identify the disease-causing gene.

RESULTS

A total of 31 members (23 from Family 1 and 8 from Family 2) had the Wolff-Parkinson-White syndrome. Affected members of both families had ventricular preexcitation with conduction abnormalities and cardiac hypertrophy. The maximal combined two-point lod score was 9.82 at a distance of 5 cM from marker D7S636, which confirmed the linkage of the gene in both families to 7q34-q36. Haplotype analysis indicated that there were no alleles in common in the two families at this locus, suggesting that the two families do not have a common founder. We identified a missense mutation in the gene that encodes the gamma2 regulatory subunit of AMP-activated protein kinase (PRKAG2). The mutation results in the substitution of glutamine for arginine at residue 302 in the protein.

CONCLUSIONS

The identification of this genetic defect has important implications for elucidating the pathogenesis of ventricular preexcitation. Further understanding of how this molecular defect leads to supraventricular arrhythmias could influence the development of specific therapies for other forms of supraventricular arrhythmia.

Identification of carbonic anhydrase XII as the membrane isozyme expressed in the normal human endometrial epithelium

Although previous studies demonstrated carbonic anhydrase (CA) activity in the human endometrium, the CA isozyme(s) responsible for this activity has not been established. In this report, we provide the first evidence that the CA isozyme XII, a recently identified transmembrane isozyme that is expressed in normal kidney and greatly overexpressed in some renal cancers, is present in endometrium. We show by immunohistochemistry that CA XII is expressed in the basolateral plasma membrane of epithelial cells of normal human endometrium. Expression of CA XII in uterus was confirmed by Northern blotting. Detergent-solubilized CA XII was isolated from human endometrium by inhibitor affinity chromatography and characterized by isoelectric focusing and Western blot as a polypeptide with a pI of 6.3. The high expression of CA XII in the endometrial epithelium suggests that it may be functionally linked to the pH-dependent events in spermatozoa that precede fertilization. Its basolateral location and extracellular active site could also allow it to influence the morphological changes in endometrium that occur during the menstrual cycle.

Utility values and diabetic retinopathy

PURPOSE

To ascertain the utility values associated with diabetic retinopathy and varying degrees of visual loss.

METHODS

One hundred consecutive patients with diabetic retinopathy and best-corrected visual acuity decreased to 20/40 or worse in at least one eye occurring primarily as a result of diabetic retinopathy were evaluated in a cross-sectional study. Utility values were ascertained in five groups using both the time trade-off and standard gamble methods: group 1 (best-corrected visual acuity in the better eye of 20/20 to 20/25), group 2 (best-corrected visual acuity in the better eye of 20/30 to 20/50), group 3 (best-corrected visual acuity in the better eye of 20/60 to 20/100), group 4 (best-corrected visual acuity in the better eye of 20/200 to 20/400), and group 5 (best-corrected visual acuity in the better eye of counting fingers to hand motions).

RESULTS

The mean utility value for the diabetic retinopathy group as a whole was 0.77 (SD = 0.21; 95% confidence interval [CI], 0.73 to 0.81) with the time trade-off method and 0.88 (SD = 0.20; 95% CI, 0.84 to 0.92) with the standard gamble method. Employing the time trade-off method correlated with the best-corrected visual acuity in the better eye, the mean utility results were as follows: group 1 = 0.85 (95% CI, 0.75 to 0.95), group 2 = 0.78 (CI, 0.72 to 0.84), group 3 = 0.78 (CI, 0.67 to 0.89), group 4 = 0.64 (CI, 0.53 to 0.75), and group 5 = 0.59 (CI, 0.23 to 0.95). Thus, patients in group 1 (best-corrected visual acuity of 20/20 to 20/25 in the better eye) were willing to trade a mean of 15% of their remaining years of life in return for perfect vision in each eye, whereas those in group 5 (best-corrected visual acuity of counting fingers to hand motions in the better eye) were willing to trade a mean of 41% of their remaining years in return for perfect vision in each eye. There was no significant difference in mean utility values between patients who had decreased visual acuity from diabetic retinopathy for 1 year or less compared with those with decreased acuity for more than 1 year. There was also no significant difference in mean utility values between those with a 12th grade education or less compared with those with more than a 12th grade education.

CONCLUSION

Visual loss occurring secondary to diabetic retinopathy is associated with a substantial decrease in patient utility value (and quality of life). The utility value is directly dependent on the degree of visual loss associated with the disease. The length of time of visual loss and amount of formal education do not appear to affect the utility value.

Why do we still use serum in the production of biopharmaceuticals?

Eukaryotic cells, in general, require serum for growth in vitro. Serum is a complex mixture of a large number of constituents, so the addition of serum introduces an ambiguous factor into cell cultivation. However, many commercially available sera are of a high uniform quality. Of these, foetal bovine serum is the most frequently used and is capable of supporting the growth of a wide variety of eukaryotic cells. However, with the identification of essential growth factors and nutrients required by different cells, several very effective serum-free media have been formulated. The use of these serum-free media is limited to a very narrow range of cells. Regulatory constraints generally make it impractical and uneconomic to alter existing biopharmaceutical production processes in which serum is used as a raw material.

Rapid tolerance and crosstolerance to motor impairment effects of benzodiazepines, barbiturates, and ethanol

Motor impairment (tilt-plane test) test was used to assess the phenomenon of rapid tolerance and crosstolerance to benzodiazepines, barbiturates, and ethanol. The motor impairment responses to benzodiazepines (chlordiazepoxide and diazepam) and to various barbiturates (pentobarbital, phenobarbital, and barbital) were significantly reduced on day 2 in rats that had been treated on day 1 with benzodiazepines and barbiturates, respectively, compared to the control group treated with saline on day 1. Benzodiazepine treatment on day 1 resulted in rapid crosstolerance to the motor impairment effects of ethanol on day 2. Benzodiazepine treatment, however, did not result in rapid crosstolerance to the three barbiturates (pentobarbital, barbital, and phenobarbital) tested. In contrast to the lack of rapid crosstolerance to barbiturates after treatment with benzodiazepines, barbiturate treatment clearly conferred rapid crosstolerance to benzodiazepines and to ethanol. This asymmetry of rapid crosstolerance raises the possibility that benzodiazepines and barbiturates invoke tolerance by mechanisms that are not wholly identical. Therefore, tolerance to the broad range of actions of barbiturates would include crosstolerance to the effects of benzodiazepines, whereas tolerance to benzodiazepines would include only a weak or partial crosstolerance to some of the effects of barbiturates.

Maternal mortality in Utah

OBJECTIVE

To determine trends in maternal deaths in Utah, identify opportunities for preventive intervention, and analyze the mechanism of reporting maternal deaths.

METHODS

A retrospective review was performed of maternal death certificates and medical records in Utah from January 1, 1982, through December 31, 1994.

RESULTS

Sixty-two maternal deaths were identified. The risk of maternal death increased with maternal age and parity. The classic triad of hemorrhage (n = 8), infection (n = 5), and preeclampsia-eclampsia (n = 3) remains an important contributor (16 of 62 or 25.8%). However, trauma (n = 10), pulmonary embolism (n = 10), and maternal cardiac disease (n = 9) now account for 46.8% (29 of 62) of maternal deaths. A greater number of direct obstetric causes of maternal death (n = 20) were deemed preventable than indirect obstetric causes (n = 1) or nonobstetric causes (n = 4).

CONCLUSION

Trauma, pulmonary embolism, and maternal cardiac disease have emerged as the most common identifiable causes of maternal death. Improvements in prevention, earlier diagnosis, and aggressive treatment of these conditions are necessary to achieve the Public Health Service year 2000 objective of a 50% reduction in maternal mortality ratios (using the 1987 ratio as a baseline).

Effect of NMDA antagonists on development of rapid tolerance to various barbiturates

We recently reported that the noncompetitive antagonists, (+)-MK-801 and ketamine, block the development of rapid tolerance to ethanol. We now show that pretreatment with these NMDA antagonists also blocks rapid tolerance to the various barbiturates (pentobarbital, barbital, and phenobarbital) examined. Tolerance to pentobarbital occurred under three difference conditions: (a) in groups of rats that were tested at repeated times on day 1 (intoxicated practice or testing group), (b) in groups of rats that were not tested on the apparatus but handled at the same times on day 1 (dummy testing or associative learning group), and (c) in groups of rats that were not subjected to testing at all on day 1 (nontesting). However, NMDA antagonists blocked intoxicated practice and associative tolerance, but not tolerance produced in the nontesting group. In the last experiment NMDA antagonist failed to block tolerance (unlearned) when animals were treated in the animal quarters and tested in a different room (i.e., in the laboratory). These findings suggest that NMDA antagonists affect barbiturate tolerance in a manner similar to their effect on ethanol tolerance.

Effect of NMDA antagonists on rapid tolerance to ethanol under two different testing paradigms

We have recently reported that pretreatment with NMDA receptor antagonists [(+)MK-801 and ketamine] inhibited the development of rapid tolerance to ethanol hypothermia and motor-impairment on day 2 in animals receiving ethanol on day 1, compared to the control group pretreated with saline. In these studies rats were tested at 30, 60, 90 and 120 min after ethanol on both day 1 and 2. In the present report we compared the development of rapid tolerance under 2 different conditions: (1) in groups of rats that were tested on the tilt-plane at all test times (Testing or Intoxicated Practice group), (2) in groups of rats that were not tested on the tilt-plane but were handled at all test times on day 1 (dummy testing). Rats were pretreated with ethanol or saline on day 1 and tested with ethanol on day 2 in all the above studies. Both testing (intoxicated practice) and dummy testing of animals on day 1 after pretreatment with ethanol produced rapid tolerance to ethanol on day 2. However, (+)MK-801 or ketamine pretreatment, which blocked rapid tolerance in the intoxicated practice testing paradigm, failed to block rapid tolerance in the dummy testing paradigm. Similar results were obtained for rapid tolerance and for the effect of ketamine in the hypothermia experiment. These findings suggest that NMDA antagonists block rapid tolerance in the intoxicated testing paradigm but not in the dummy testing paradigm. However, whether the two types of rapid tolerance tested in the present experiments are indeed different or interrelated remains to be further investigated.

Incidence of posterior capsular plaque in cataract surgery

OBJECTIVE

To determine the incidence of posterior capsular plaque detected during cataract surgery, its association with age and type of cataract, and its impact on vision.

SETTING

Raghudeep Eye Clinic and Iladevi Cataract & IOL Research Centre, Ahmedabad, India.

METHODS

This prospective study comprised 256 consecutive eyes having extracapsular cataract extraction with posterior chamber intraocular lens implantation. The presence of plaque on the posterior capsule was noted and charted. Plaque peeling or posterior capsulorhexis was not done at the time of surgery. Mean patient age was 59 years (range 24 to 83 years). Follow-up was up to 1 year.

RESULTS

The overall incidence of plaque was 10.16%. The incidence by type of cataract was 5.13%, nuclear sclerotic; 12.50%, posterior subcapsular; 9.68%, mixed; 27.27%, mature (P < .05). The difference in incidence according to cataract type was highly significant between patients older than 50 years and those younger than 50 years (P < .001). At the end of 1 year, 61.54% of patients with plaque maintained a visual acuity of 20/20 to 20/30; 30.77%, 20/40; 7.69%, 20/60 or worse.

CONCLUSION

The incidence of plaque was higher in eyes with mature cataract at any age and in eyes with posterior subcapsular cataract in younger patients. Its presence was compatible with reasonable vision at the end of 1 year.