Extent of microstructural white matter injury in postconcussive syndrome correlates with impaired cognitive reaction time: a 3T diffusion tensor imaging study of mild traumatic brain injury

BACKGROUND AND PURPOSE

Diffusion tensor imaging (DTI) may be a useful index of microstructural changes implicated in diffuse axonal injury (DAI) linked to persistent postconcussive symptoms, especially in mild traumatic brain injury (TBI), for which conventional MR imaging techniques may lack sensitivity. We hypothesized that for mild TBI, DTI measures of DAI would correlate with impairments in reaction time, whereas the number of focal lesions on conventional 3T MR imaging would not.

MATERIALS AND METHODS

Thirty-four adult patients with mild TBI with persistent symptoms were assessed for DAI by quantifying traumatic microhemorrhages detected on a conventional set of T2*-weighted gradient-echo images and by DTI measures of fractional anisotropy (FA) within a set of a priori regions of interest. FA values 2.5 SDs below the region average, based on a group of 26 healthy control adults, were coded as exhibiting DAI.

RESULTS

DTI measures revealed several predominant regions of damage including the anterior corona radiata (41% of the patients), uncinate fasciculus (29%), genu of the corpus callosum (21%), inferior longitudinal fasciculus (21%), and cingulum bundle (18%). The number of damaged white matter structures as quantified by DTI was significantly correlated with mean reaction time on a simple cognitive task (r = 0.49, P = .012). In contradistinction, the number of traumatic microhemorrhages was uncorrelated with reaction time (r = -0.08, P = .71).

CONCLUSION

Microstructural white matter lesions detected by DTI correlate with persistent cognitive deficits in mild TBI, even in populations in which conventional measures do not. DTI measures may thus contribute additional diagnostic information related to DAI.

Effect of niacin on lipid and lipoprotein levels and glycemic control in patients with diabetes and peripheral arterial disease: the ADMIT study: A randomized trial. Arterial Disease Multiple Intervention Trial

CONTEXT

Although niacin increases low levels of high-density lipoprotein cholesterol (HDL-C), which frequently accompany diabetes, current guidelines do not recommend use of niacin in patients with diabetes because of concerns about adverse effects on glycemic control; however, this is based on limited clinical data.

OBJECTIVE

To determine the efficacy and safety of lipid-modifying dosages of niacin in patients with diabetes.

DESIGN AND SETTING

Prospective, randomized placebo-controlled clinical trial conducted in 6 clinical centers from August 1993 to December 1995.

PARTICIPANTS

A total of 468 participants, including 125 with diabetes, who had diagnosed peripheral arterial disease.

INTERVENTIONS

After an active run-in period, participants were randomly assigned to receive niacin (crystalline nicotinic acid), 3000 mg/d or maximum tolerated dosage (n = 64 with diabetes; n = 173 without diabetes), or placebo (n = 61 with diabetes; n = 170 without diabetes) for up to 60 weeks (12-week active run-in and 48-week double-blind).

MAIN OUTCOME MEASURES

Plasma lipoprotein, glucose, hemoglobin A(1c) (HbA(1c)), alanine aminotransferase, and uric acid levels; hypoglycemic drug use; compliance; and adverse events, in patients with diabetes vs without who were receiving niacin vs placebo.

RESULTS

Niacin use significantly increased HDL-C by 29% and 29% and decreased triglycerides by 23% and 28% and low-density lipoprotein cholesterol (LDL-C) by 8% and 9%, respectively, in participants with and without diabetes (P<.001 for niacin vs placebo for all). Corresponding changes in participants receiving placebo were increases of 0% and 2% in HDL-C and increases of 7% and 0% in triglycerides, and increases of 1% and 1% in LDL-C. Glucose levels were modestly increased by niacin (8.7 and 6.3 mg/dL [0.4 and 0.3 mmol/L]; P =.04 and P<.001) in participants with and without diabetes, respectively. Levels of HbA(1c) were unchanged from baseline to follow-up in participants with diabetes treated with niacin. In participants with diabetes treated with placebo, HbA(1c) decreased by 0.3% (P =.04 for difference). There were no significant differences in niacin discontinuation, niacin dosage, or hypoglycemic therapy in participants with diabetes assigned to niacin vs placebo.

CONCLUSIONS

Our study suggests that lipid-modifying dosages of niacin can be safely used in patients with diabetes and that niacin therapy may be considered as an alternative to statin drugs or fibrates for patients with diabetes in whom these agents are not tolerated or fail to sufficiently correct hypertriglyceridemia or low HDL-C levels. JAMA. 2000;284:1263-1270

Mutations in the RNA component of RNase MRP cause a pleiotropic human disease, cartilage-hair hypoplasia

The recessively inherited developmental disorder, cartilage-hair hypoplasia (CHH) is highly pleiotropic with manifestations including short stature, defective cellular immunity, and predisposition to several cancers. The endoribonuclease RNase MRP consists of an RNA molecule bound to several proteins. It has at least two functions, namely, cleavage of RNA in mitochondrial DNA synthesis and nucleolar cleaving of pre-rRNA. We describe numerous mutations in the untranslated RMRP gene that cosegregate with the CHH phenotype. Insertion mutations immediately upstream of the coding sequence silence transcription while mutations in the transcribed region do not. The association of protein subunits with RNA appears unaltered. We conclude that mutations in RMRP cause CHH by disrupting a function of RNase MRP RNA that affects multiple organ systems.

Megestrol acetate for the prevention of hot flashes

BACKGROUND

Vasomotor hot flashes are a common symptom in women during menopause and in men who have undergone androgen-deprivation therapy for prostate cancer. Although treatment with estrogens in women and androgens in men can attenuate these symptoms, these hormones may be contraindicated in women with breast cancer and in men with prostate cancer. Pilot trials have suggested that the progestational agent megestrol acetate can ameliorate hot flashes in both groups of patients.

METHODS

The patients included 97 women with a history of breast cancer and 66 men with prostate cancer who had undergone androgen-deprivation therapy. All patients had experienced bothersome hot flashes (median number per day at base line, 6.1 for the women and 8.4 for the men). After a one-week pretreatment observation period, the patients received megestrol acetate (20 mg twice daily) for four weeks, followed by placebo for four weeks, or vice versa in a double-blind manner as determined by pretreatment randomization. The patients documented the frequency and severity of hot flashes in daily symptom diaries.

RESULTS

After four weeks, hot flashes were reduced by 21 percent in the group receiving placebo first and by 85 percent in the group receiving megestrol acetate first (P < 0.001). An intention-to-treat analysis of data for all eligible treated patients showed that 74 percent of the megestrol acetate group, as compared with 20 percent of the placebo group, had a decrease of 50 percent or more in the frequency of hot flashes during the first four weeks (P < 0.001). The degree of efficacy was similar in men and women. The only side effect was withdrawal menstrual bleeding in women, generally occurring one to two weeks after the megestrol acetate had been discontinued.

CONCLUSIONS

Low-dose megestrol acetate is well tolerated and can substantially decrease the frequency of hot flashes in women and men.

Use of the selective oral neuraminidase inhibitor oseltamivir to prevent influenza

BACKGROUND

Safe and effective antiviral agents are needed to prevent infection with influenza A and B virus. Oseltamivir (GS4104), which can be administered orally, is the prodrug of GS4071, a potent and selective inhibitor of influenzavirus neuraminidases. We studied the use of oseltamivir for long-term prophylaxis against influenza in two placebo-controlled, double-blind trials at different U.S. sites during the winter of 1997-1998.

METHODS

We randomly assigned 1559 healthy, nonimmunized adults 18 to 65 years old to receive either oral oseltamivir (75 mg given once or twice daily, for a total daily dose of 75 or 150 mg) or placebo for six weeks during a peak period of local influenzavirus activity. The primary end point with respect to efficacy was laboratory-confirmed influenza-like illness (defined as a temperature of at least 37.2 degrees C accompanied by at least one respiratory and at least one systemic symptom).

RESULTS

In the two studies combined, the risk of influenza among subjects assigned to either once-daily or twice-daily oseltamivir (1.2 percent and 1.3 percent, respectively) was lower than that among subjects assigned to placebo (4.8 percent; P<0.001 and P=0.001 for the comparison with once-daily and twice-daily oseltamivir, respectively). The protective efficacy of oseltamivir in the two active-treatment groups combined was 74 percent (95 percent confidence interval, 53 to 88 percent) at all the sites combined and 82 percent (95 percent confidence interval, 60 to 93 percent) at sites in Virginia, where the rate of influenza infection was higher than the overall rate. For culture-proved influenza, the rate of protective efficacy in the two oseltamivir groups combined was 87 percent (95 percent confidence interval, 65 to 96 percent). The rate of laboratory-confirmed influenza infection was lower with oseltamivir than with placebo (5.3 percent vs. 10.6 percent, P<0.001). Oseltamivir was well tolerated but was associated with a greater frequency of nausea (12.1 percent and 14.6 percent in the once-daily and twice-daily groups, respectively) and vomiting (2.5 percent and 2.7 percent, respectively) than was placebo (nausea, 7.1 percent; vomiting, 0.8 percent). However, the frequency of premature discontinuation of drug or placebo was similar among the three groups (3.1 to 4.0 percent).

CONCLUSIONS

Oseltamivir administered daily for six weeks by the oral route is safe and effective for the prevention of influenza.

Influence of glaucomatous visual field loss on health-related quality of life

We examined the influence of glaucomatous visual field defects on vision-targeted and generic health-related quality of life. Vision-targeted and generic health status were assessed across 5 glaucoma treatment categories and a normal reference group from 5 tertiary care ophthalmology practices during regularly scheduled eye care visits. The sample consisted of 147 patients who were members of specific glaucoma treatment categories and 44 reference group patients. For patients with glaucoma, eligibility included a diagnosis of glaucoma at least 1 year prior to enrollment and no evidence of other eye disease. Participants completed 2 vision-targeted surveys, the National Eye Institute Visual Functioning Questionnaire and the VF-14, and a generic health-related quality of life measure, the Medical Outcomes Study 36-Item Short Form. Data from automated perimetry (Humphrey Field Analyzer 24-2, Humphrey Instruments, San Leandro, Calif) were used to generate Advanced Glaucoma Intervention Study scores for all participants. The Medical Outcomes Study 36-Item Short Form scores from glaucoma and reference group participants collected on a random half of the sample were similar. However, comparisons of the vision-targeted surveys demonstrated significant mean differences on 7 of 11 National Eye Institute Visual Functioning Questionnaire scales, and a trend toward significant differences for the VF-14 (P < .07 by linear regression). Greater visual field defects in the better eye were significantly associated with poorer National Eye Institute Visual Functioning Questionnaire scores (P < .05), as well as with worse VF-14 scores. These findings were most dramatic for patients with the most severe field loss in the better eye. Vision-targeted questionnaires were more sensitive than a generic health-related quality of life measure to differences between glaucoma and normal reference participants. Our findings indicate that self-reports of vision-targeted health-related quality of life are sensitive to visual field loss and may be useful in tandem with the clinical examination to fully understand outcomes of treatment for glaucoma.

Detecting colorectal cancer in stool with the use of multiple genetic targets

BACKGROUND

Colorectal cancer cells are shed into the stool, providing a potential means for the early detection of the disease using noninvasive approaches. Our goal was to develop reliable, specific molecular genetic tests for the detection of colorectal cancer in stool samples.

METHODS

Stool DNA was isolated from paired stools and primary tumor samples from 51 colorectal cancer patients. Three genetic targets-TP53, BAT26, and K-RAS-were used to detect tumor-associated mutations in the stool prior to or without regard to the molecular analyses of the paired tumors. TP53 gene mutations were detected with a mismatch-ligation assay that detects nine common p53 gene mutations. Deletions within the BAT26 locus were detected by a modified solid-phase minisequencing method. Mutations in codons 12 and 13 of K-RAS were detected with a digital polymerase chain reaction-based method.

RESULTS

TP53 gene mutations were detected in the tumor DNA of 30 patients, all of whom had the identical TP53 mutation in their stools. Tumors from three patients contained a noninherited deletion at the BAT26 locus, and the same alterations were identified in these patients' stool specimens. Nineteen of 50 tumors tested had a K-RAS mutation; identical mutations were detected in the paired stool DNA samples from eight patients. In no case was a mutation found in stool that was not also present in the primary tumor. Thus, the three genetic markers together detected 36 (71%) of 51 patients (95% confidence interval [CI] = 56% to 83%) with colorectal cancer and 36 (92%) of 39 patients (95% CI = 79% to 98%) whose tumors had an alteration.

CONCLUSION

We were able to detect the majority of colorectal cancers by analyzing stool DNA for just three genetic markers. Additional work is needed to determine the specificity of these genetic tests for detecting colorectal neoplasia in asymptomatic patients and to more precisely estimate the prevalence of the mutations and sensitivity of the assay.

The clinical and economic value of a short course of omeprazole in patients with noncardiac chest pain

BACKGROUND & AIMS

Evaluation of new patients with noncardiac chest pain (NCCP) may require a variety of costly tests. The aim of this study was to evaluate the efficacy of the omeprazole test (OT) in diagnosing gastroesophageal reflux (GERD) in patients with NCCP and estimate the potential cost savings of this strategy compared with conventional diagnostic evaluations.

METHODS

Thirty-nine patients referred by cardiologists were enrolled. Baseline symptoms were recorded, and the patients were randomized to either placebo or omeprazole (40 mg AM and 20 mg PM) groups for 7 days. Patients were crossed over to the other arm after a washout period and repeat baseline symptom assessment. All patients underwent 24-hour esophageal pH monitoring and upper endoscopy before randomization.

RESULTS

Thirty-seven patients (94.9%) completed the study. Twenty-three (62.2%) were classified as GERD positive and 14 as GERD negative. Eighteen (78%) GERD-positive patients and 2 (14%) GERD-negative patients had a positive OT (P < 0.01), yielding a sensitivity of 78.3% (95% confidence interval, 61.4-95.1) and specificity of 85.7% (95% confidence interval, 67.4-100). Economic analysis showed that the OT saves $573 per average patient evaluated and results in a 59% reduction in the number of diagnostic procedures.

CONCLUSIONS

The OT is sensitive and specific for diagnosing GERD in patients with NCCP. This strategy results in significant cost savings and decreased use of diagnostic tests.

Bulimia: an analysis of moods and behavior

An innovative sampling method was used to compare normal-weight bulimic patients to normal controls on four dimensions: (1) overall moods, (2) extent of mood fluctuating, (3) degree of social isolation, and (4) extent of food-related behavior. In addition, a sequence analysis was conducted to explore the impact of binging and purging episodes on various affective states among the bulimics. Results indicated that the bulimics experienced significantly more dysphoric and fluctuating moods than normal controls and that they spent much more time alone and in food-related behavior than the control group. The discussion presents a hypothetical integration regarding the etiology and maintenance of the bulimic behavior based on the results of the data and post-trial interviews with the bulimic patients.

Differential effect of long-term esophageal acid exposure on mechanosensitivity and chemosensitivity in humans

BACKGROUND & AIMS

Chronic tissue injury in the esophagus associated with gastroesophageal reflux disease may result in sensitization of afferent pathways mediating mechanosensitivity and chemosensitivity. The aim of this study was to evaluate the sensitivity to intraluminal acid and to distention of the esophagus in patients with mild-to-moderate gastroesophageal reflux disease.

METHODS

Perceptual responses to intraluminal acid perfusion and to esophageal distention and pressure volume relationships were evaluated in 10 healthy volunteers and in 11 patients. Mechanosensitivity was evaluated with a barostat using unbiased distention protocols and verbal descriptor ratings of sensations. Chemosensitivity to acid was determined at baseline and after a 1-month treatment of acid suppression.

RESULTS

Patients showed enhanced perception of acid perfusion but not of esophageal distension. Chemosensitivity but not mechanosensitivity was correlated with reflux symptoms and with the degree of endoscopically shown tissue injury at baseline. Tissue injury was not associated with altered compliance.

CONCLUSIONS

Mild-to-moderate chronic tissue injury in gastroesophageal reflux disease differentially affects mechanosensitive and chemosensitive afferent pathways. Chronic acid reflux by itself is not likely to play a role in reported esophageal hypersensitivity to distention in patients with noncardiac chest pain.

Three-year maintenance of improved diet and physical activity: the CATCH cohort. Child and Adolescent Trial for Cardiovascular Health

OBJECTIVE

To assess differences through grade 8 in diet, physical activity, and related health indicators of students who participated in the Child and Adolescent Trial for Cardiovascular Health (CATCH) school and family intervention from grades 3 through 5.

DESIGN

Follow-up of the 4-center, randomized, controlled field trial with 56 intervention and 40 control elementary schools.

PARTICIPANTS

We studied 3714 (73%) of the initial CATCH cohort of 5106 students from ethnically diverse backgrounds in California, Louisiana, Minnesota, and Texas at grades 6, 7, and 8.

RESULTS

Self-reported daily energy intake from fat at baseline was virtually identical in the control (32.7%) and intervention (32.6%) groups. At grade 5, the intake for controls remained at 32.2%, while the intake for the intervention group declined to 30.3% (P<.001). At grade 8, the between-group differential was maintained (31.6% vs 30.6%, P = .01). Intervention students maintained significantly higher self-reported daily vigorous activity than control students (P = .001), although the difference declined from 13.6 minutes in grade 5 to 11.2, 10.8, and 8.8 minutes in grades 6, 7, and 8, respectively. Significant differences in favor of the intervention students also persisted at grade 8 for dietary knowledge and dietary intentions, but not for social support for physical activity. No impact on smoking behavior or stages of contemplating smoking was detected at grade 8. No significant differences were noted among physiologic indicators of body mass index, blood pressure, or serum lipid and cholesterol levels.

CONCLUSION

The original CATCH results demonstrated that school-level interventions could modify school lunch and school physical education programs as well as influence student behaviors. This 3-year follow-up without further intervention suggests that the behavioral changes initiated during the elementary school years persisted to early adolescence for self-reported dietary and physical activity behaviors.

Chronic renal failure in sickle cell disease: risk factors, clinical course, and mortality

OBJECTIVE

To determine the incidence, clinical course, and risk factors associated with the onset of chronic renal failure in sickle cell anemia and sickle C disease.

DESIGN

A prospective, 25-year longitudinal demographic and clinical cohort study. A matched case-control study was conducted to determine risk factors.

PATIENTS

A total of 725 patients with sickle cell anemia and 209 patients with sickle C disease who received medical care from the hematology service in a large municipal hospital. Most were observed from birth or early childhood.

MEASUREMENTS

Thirty-six patients developed sickle renal failure: 4.2% of patients with sickle cell anemia and 2.4% of patients with sickle C disease. The median age of disease onset for these patients was 23.1 and 49.9 years, respectively. Survival time for patients with sickle cell anemia after the diagnosis of sickle renal failure, despite dialysis, was 4 years, and the median age at the time of death was 27 years. Relative risk for mortality was 1.42 (95% Cl, 1.12 to 1.81; P = 0.02) compared with patients who did not develop renal insufficiency.

MAIN RESULTS

Histopathologic studies showed characteristic lesions of glomerular "drop out" and glomerulosclerosis. Case-control analysis showed that ineffective erythropoiesis with increasingly severe anemia, hypertension, proteinuria, the nephrotic syndrome, and microscopic hematuria were significant pre-azotemic predictors of chronic renal failure. The risk for sickle renal failure was increased in patients who had inherited the Central African Republic beta s-gene cluster haplotype.

CONCLUSIONS

The pre-azotemic manifestations of hypertension, proteinuria, and increasingly severe anemia predict end-stage renal failure in patients with sickle cell disease. The rate of progression of renal insufficiency is genetically determined. Treatment of the uremic phase has been dismal, underscoring the need for the development of useful pre-azotemic therapeutic modalities.

Randomized trial of tacrolimus (Prograf) in combination with azathioprine or mycophenolate mofetil versus cyclosporine (Neoral) with mycophenolate mofetil after cadaveric kidney transplantation

BACKGROUND

Our clinical trial was designed to investigate the optimal combination of immunosuppressants for renal transplantation.

METHODS

A randomized three-arm, parallel group, open label, prospective study was performed at 15 North American centers to compare three immunosuppressive regimens: tacrolimus + azathioprine (AZA) versus cyclosporine (Neoral) + mycophenolate mofetil (MMF) versus tacrolimus + MMF. All patients were first cadaveric kidney transplants receiving the same maintenance corticosteroid regimen. Only patients with delayed graft function (32%) received antilymphocyte induction. A total of 223 patients were randomized, transplanted, and followed for 1 year.

RESULTS

There were no significant differences in baseline demography between the three treatment groups. At 1 year the results are as follows: acute rejection 17% (95% confidence interval 9%, 26%) in tacrolimus + AZA; 20% (confidence interval 11%, 29%) in cyclosporine + MMF; and 15% (confidence interval 7%, 24%) in tacrolimus + MMF. The incidence of steroid resistant rejection requiring antilymphocyte therapy was 12% in the tacrolimus + AZA group, 11% in the cyclosporine + MMF group, and 4% in the tacrolimus + MMF group. There were no significant differences in overall patient or graft survival. Tacrolimus-treated patients had a lower incidence of hyperlipidemia through 6 months posttransplant. The incidence of posttransplant diabetes mellitus requiring insulin was 14% in the tacrolimus + AZA group, 7% in the cyclosporine + MMF and 7% in the tacrolimus + MMF groups.

CONCLUSIONS

All regimens yielded similar acute rejection rates and graft survival, but the tacrolimus + MMF regimen was associated with the lowest rate of steroid resistant rejection requiring antilymphocyte therapy.

Rapid assay for screening and characterizing microorganisms for the ability to degrade polychlorinated biphenyls

We designed a rapid assay that assesses the polychlorinated biphenyl (PCB)-degradative competence and congener specificity of aerobic microorganisms, identifies strains capable of degrading highly chlorinated biphenyls, and distinguishes among those that degrade PCBs by alternative pathways. Prior attempts to assay PCB-degradative competence by measuring disappearance of Aroclors (commercial PCB mixtures) have frequently produced false-positive findings because of volatilization, adsorption, or absorption losses. Furthermore, these assays have generally left the chemical nature of the competence obscure because of incomplete gas chromatographic resolution and uncertain identification of Aroclor peaks. We avoided these problems by using defined mixtures of PCB congeners and by adopting incubation and extraction methods that prevent physical loss of PCBs. Our assay mixtures include PCB congeners ranging from dichloro- to hexachlorobiphenyls and representing various structural classes, e.g., congeners chlorinated on a single ring (2,3-dichlorobiphenyl), blocked at 2,3 sites (2,5,2'5'-tetrachlorobiphenyl), blocked at 3,4 sites (4,4'-dichlorobiphenyl), and lacking adjacent unchlorinated sites (2,4,5,2',4',5'-hexachlorobiphenyl). The PCB-degrative ability of microorganisms is assessed by packed-column gas chromatographic analysis of these defined congener mixtures following 24-h incubation with resting cells. When tested with 25 environmental isolates, this assay revealed a broad range of PCB-degradative competence, highlighted differences in congener specificity and in the extent of degradation of individual congeners, predicted degradative competence on commercial PCBs, and (iv) identified strains with superior PCB-degradative ability.

GABA-producing Bifidobacterium dentium modulates visceral sensitivity in the intestine

BACKGROUND

Recurrent abdominal pain is a common and costly health-care problem attributed, in part, to visceral hypersensitivity. Increasing evidence suggests that gut bacteria contribute to abdominal pain perception by modulating the microbiome-gut-brain axis. However, specific microbial signals remain poorly defined. γ-aminobutyric acid (GABA) is a principal inhibitory neurotransmitter and a key regulator of abdominal and central pain perception from peripheral afferent neurons. Although gut bacteria are reported to produce GABA, it is not known whether the microbial-derived neurotransmitter modulates abdominal pain.

METHODS

To investigate the potential analgesic effects of microbial GABA, we performed daily oral administration of a specific Bifidobacterium strain (B. dentiumATCC 27678) in a rat fecal retention model of visceral hypersensitivity, and subsequently evaluated pain responses.

KEY RESULTS

We demonstrate that commensal Bifidobacterium dentium produces GABA via enzymatic decarboxylation of glutamate by GadB. Daily oral administration of this specific Bifidobacterium (but not a gadB deficient) strain modulated sensory neuron activity in a rat fecal retention model of visceral hypersensitivity.

CONCLUSIONS & INFERENCES

The functional significance of microbial-derived GABA was demonstrated by gadB-dependent desensitization of colonic afferents in a murine model of visceral hypersensitivity. Visceral pain modulation represents another potential health benefit attributed to bifidobacteria and other GABA-producing species of the intestinal microbiome. Targeting GABAergic signals along this microbiome-gut-brain axis represents a new approach for the treatment of abdominal pain.

The bHLH transcription factor Mist1 is required to maintain exocrine pancreas cell organization and acinar cell identity

The pancreas is a complex organ that consists of separate endocrine and exocrine cell compartments. Although great strides have been made in identifying regulatory factors responsible for endocrine pancreas formation, the molecular regulatory circuits that control exocrine pancreas properties are just beginning to be elucidated. In an effort to identify genes involved in exocrine pancreas function, we have examined Mist1, a basic helix-loop-helix transcription factor expressed in pancreatic acinar cells. Mist1-null (Mist1(KO)) mice exhibit extensive disorganization of exocrine tissue and intracellular enzyme activation. The exocrine disorganization is accompanied by increases in p8, RegI/PSP, and PAP1/RegIII gene expression, mimicking the molecular changes observed in pancreatic injury. By 12 m, Mist1(KO) mice develop lesions that contain cells coexpressing acinar and duct cell markers. Analysis of the factors involved in cholecystokinin (CCK) signaling reveal inappropriate levels of the CCK receptor A and the inositol-1,4,5-trisphosphate receptor 3, suggesting that a functional defect exists in the regulated exocytosis pathway of Mist1(KO) mice. Based on these observations, we propose that Mist1(KO) mice represent a new genetic model for chronic pancreas injury and that the Mist1 protein serves as a key regulator of acinar cell function, stability, and identity.

An N-terminal nuclear export signal is required for the nucleocytoplasmic shuttling of IkappaBalpha

The potent transcriptional activities of Rel/NF-kappaB proteins are regulated in the cytoplasm and nucleus by the inhibitor, IkappaBalpha. The mechanism, by which IkappaBalpha can either sequester NF-kappaB in the cytoplasm or act as a nuclear post-induction repressor of NF-kappaB, is uncertain. We find that IkappaBalpha shuttles continuously between the nucleus and cytoplasm. This shuttling requires a previously unidentified CRM1-dependent nuclear export signal (NES) located within the N-terminal domain of IkappaBalpha at amino acids 45-55. Deletion or mutation of the N-terminal NES results in nuclear localization of IkappaBalpha. NF-kappaB (p65) association with IkappaBalpha affects steady-state localization but does not inhibit its shuttling. Endogenous complexes of IkappaBalpha-NF-kappaB shuttle and will accumulate in the nucleus when CRM1 export is blocked. We find TNFalpha can activate the nuclear IkappaBalpha-NF-kappaB complexes by the classical mechanism of proteasome-mediated degradation of IkappaBalpha. These studies reveal a more dynamic nucleocytoplasmic distribution for IkappaBalpha and NF-kappaB suggesting previously unknown strategies for regulating this ubiquitous family of transcription activators.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Elevated cytokine concentrations in the nasopharyngeal and tracheal secretions of children with respiratory syncytial virus disease

BACKGROUND

Respiratory syncytial virus (RSV) is the most common cause of lower respiratory tract disease in infants. The role of inflammatory mediators in the pathogenesis of RSV disease is not well-understood. The present study was designed (1) to determine whether RANTES (regulated on activation, normal T cell expressed and presumably secreted), macrophage-inflammatory protein-1-alpha (MIP-1-alpha), interleukin (IL)-6, IL-8 and IL-10 can be detected in respiratory secretions of children with RSV infection and (2) to assess whether the concentrations of these cytokines in respiratory secretions correlate with white blood cell (WBC) counts and RSV concentrations and with disease severity.

METHODS

During the 1996 to 1997 RSV season, we studied prospectively 14 intubated and 14 nonintubated children hospitalized with RSV disease. Nasal wash (NW) and tracheal aspirate (TA) samples were obtained from intubated patients on Hospital Days 1, 3 and 5. NW samples were obtained from nonintubated patients on hospital days 1 and 3. Seven healthy children undergoing elective surgery served as controls. All samples were analyzed for: (1) WBC and differential counts; (2) concentrations of RANTES, MIP-1-alpha, IL-6, IL-8 and IL-10; and (3) quantitative RSV cultures, except in control patients.

RESULTS

RANTES, MIP-1-alpha, IL-6, IL-8 and IL-10 were detected in NW and TA samples from all children with RSV infection. The concentrations of these cytokines in samples obtained from children with RSV infection were significantly greater than those in samples obtained from control children. NW WBC counts significantly correlated with NW RANTES, IL-6, IL-8 and IL-10 concentrations, whereas TA WBC counts significantly correlated with TA IL-6, IL-8, IL-10 and MIP-1-alpha concentrations. NW RSV concentrations correlated with NW WBC counts and with NW cytokine concentrations. Among children with RSV infection nonintubated patients had greater NW WBC counts and NW RANTES concentrations than intubated patients. TA RANTES, IL-8 and IL-10 concentrations inversely correlated with clinical markers of RSV disease severity.

CONCLUSION

The presence of cytokines in NW and TA samples of children with RSV infection suggests that they have a role in mediating the respiratory tract inflammation induced by RSV. These observations could have implications for designing new therapeutic strategies directed at immunomodulation of RSV disease.

Exposure to traumatic incidents and prevalence of posttraumatic stress symptomatology in urban firefighters in two countries

Urban firefighters are at risk for posttraumatic stress disorder (PTSD) due in part to their exposure to duty-related trauma. This study compared duty-related trauma exposures and the prevalences of posttraumatic stress in U.S. and Canadian firefighters. Both samples reported relatively numerous and frequent posttrauma symptoms, and the rates of self-reported PTSD prevalence did not differ significantly. However, analysis of departmental records for respondents' previous year on duty revealed significant differences in both frequencies and categories of traumatic incident exposures. Some of the vulnerability and moderating risk factors associated with PTSD caseness differed between the U.S. and Canadian samples. Potential explanations for the observed differences in risk factors for PTSD in these 2 firefighter samples are considered.

Prevalence and causes of anemia in the United States, 1976 to 1980

We estimated the prevalence of anemia in the United States from the results of the Second National Health and Nutrition Examination Survey ( NHANES II, 1976 to 1980). Reference ranges for Hb were first derived from 11,547 subjects in whom laboratory values for serum iron/iron-binding capacity, mean corpuscular volume, and erythrocyte protoporphyrin were all normal (greater than or equal to 16%, greater than or equal to 80 fl, and less than or equal to 75 micrograms/dl red blood cells, respectively). Using these reference standards, the prevalence of anemia (Hb values below the 95% reference range for age and sex) among the 15,093 subjects with complete laboratory results was highest in infants (5.7%), teenage girls (5.9%), young women (5.8%), and elderly men (4.4%). The pattern of laboratory abnormalities in anemic subjects indicated that iron deficiency predominated as a cause in infants and young women in contrast to inflammatory disease in the elderly.

Stroke in children and sickle-cell disease: Baltimore-Washington Cooperative Young Stroke Study

BACKGROUND/PURPOSE

The Baltimore-Washington Cooperative Young Stroke Study is the largest biracial urban-suburban population-based study to examine the etiology of strokes in children.

METHODS

We identified all children aged 1 to 14 years discharged from all 46 hospitals in central Maryland and Washington, DC with a diagnosis of ischemic stroke and intracerebral hemorrhage in the years 1988 and 1991. Each medical record was reviewed by two neurologists for appropriateness of the diagnosis of stroke and for information on the patient's history, clinical presentation, pertinent investigations, hospital stay, and outcome at time of discharge.

RESULTS

Eighteen children with ischemic infarction and 17 with intracerebral hemorrhage were identified. The most common cause of ischemic stroke was sickle-cell disease (39%), followed by vasculopathic (33%) and indeterminate (28%) causes. Causes of intracerebral hemorrhages were arteriovenous malformation (29%), hematologic (23%), vasculopathy (18%), surgical complication (12%), coagulopathy (6%), and indeterminate (12%). The overall incidence for childhood stroke was 1.29 per 100,000 per year, with ischemic stroke occurring at a rate of 0.58 per 100,000 and intracerebral hemorrhage occurring at a rate of 0.71 per 100,000. The incidence of stroke among children with sickle-cell disease was estimated to be 0.28% or 285 per 100,000 per year.

CONCLUSION

Sickle-cell disease plays a disproportionately high role in childhood stroke when a biracial population is surveyed.