Continuous passive paracentesis versus large-volume paracentesis in the prevention and treatment of intra-abdominal hypertension in the critically ill cirrhotic patient with ascites (COPPTRIAHL): study protocol for a randomized controlled trial

BACKGROUND

Critically ill patients with cirrhosis and ascites are at high risk for intra-abdominal hypertension (IAH) which increases mortality. Clinical guidelines recommend maintaining intra-abdominal pressure (IAP) below 16 mmHg; nonetheless, more than three quarters of critically ill patients with cirrhosis develop IAH during their first week of ICU stay. Standard-of-care intermittent large-volume paracentesis (LVP) relieves abdominal wall tension, reduces IAP, optimizes abdominal perfusion pressure, and is associated with short-term improvement in renal and pulmonary dysfunction. However, there is no evidence of the superiority of different paracentesis strategies in the prevention and treatment of IAH in critically ill patients with cirrhosis. This trial aims to compare the outcomes of continuous passive paracentesis versus LVP in the prevention and treatment of IAH in patients with cirrhosis and ascites.

METHODS

An investigator-initiated, open label, randomized controlled trial, set in a general ICU specialized in liver disease, was initiated in August 2022, with an expected duration of 36 months. Seventy patients with cirrhosis and ascites will be randomly assigned, in a 1:1 ratio, to receive one of two methods of therapeutic paracentesis. A stratified randomization method, with maximum creatinine and IAP values as strata, will homogenize patient baseline characteristics before trial group allocation, within 24 h of admission. In the control group, LVP will be performed intermittently according to clinical practice, with a maximum duration of 8 h, while, in the intervention group, continuous passive paracentesis will drain ascitic fluid for up to 7 days. The primary endpoint is serum creatinine concentration, and secondary endpoints include IAP, measured creatinine clearance, daily urine output, stage 3 acute kidney injury and multiorgan dysfunction assessed at day 7 after enrollment, as well as 28-day mortality rate and renal replacement therapy-free days, and length-of-stay. Prespecified values will be used in case of renal replacement therapy or, beforehand ICU discharge, liver transplant and death. Safety analysis will include paracentesis-related complication rate and harm. Data will be analyzed with an intention-to-treat approach.

DISCUSSION

This is the first trial to compare the impact of different therapeutic paracentesis strategies on organ dysfunction and outcomes in the prevention and treatment of IAH in critically ill patients with cirrhosis and ascites.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04322201 . Registered on 20 December 2019.

Abdominal perfusion pressure in critically ill cirrhotic patients: a prospective observational study

In critical patients, abdominal perfusion pressure (APP) has been shown to correlate with outcome. However, data from cirrhotic patients is scarce. We aimed to characterize APP in critically ill cirrhotic patients, analyze the prevalence and risk factors of abdominal hypoperfusion (AhP) and outcomes. A prospective cohort study in a general ICU specialized in liver disease at a tertiary hospital center recruited consecutive cirrhotic patients between October 2016 and December 2021. The study included 101 patients, with a mean age of 57.2 (± 10.4) years and a female gender proportion of 23.5%. The most frequent etiology of cirrhosis was alcohol (51.0%), and the precipitant event was infection (37.3%). ACLF grade (1-3) distribution was 8.9%, 26.7% and 52.5%, respectively. A total of 1274 measurements presented a mean APP of 63 (± 15) mmHg. Baseline AhP prevalence was 47%, independently associated with paracentesis (aOR 4.81, CI 95% 1.46-15.8, p = 0.01) and ACLF grade (aOR 2.41, CI 95% 1.20-4.85, p = 0.01). Similarly, AhP during the first week (64%) had baseline ACLF grade (aOR 2.09, CI 95% 1.29-3.39, p = 0.003) as a risk factor. Independent risk factors for 28-day mortality were bilirubin (aOR 1.10, CI 95% 1.04-1.16, p < 0.001) and SAPS II score (aOR 1.07, CI 95% 1.03-1.11, p = 0.001). There was a high prevalence of AhP in critical cirrhotic patients. Abdominal hypoperfusion was independently associated with higher ACLF grade and baseline paracentesis. Risk factors for 28-day mortality included clinical severity and total bilirubin. The prevention and treatment of AhP in the high-risk cirrhotic patient is prudential.

What changed between the peak and plateau periods of the first COVID-19 pandemic wave? A multicentric Portuguese cohort study in intensive care

OBJECTIVE

To analyze and compare COVID-19 patient characteristics, clinical management and outcomes between the peak and plateau periods of the first pandemic wave in Portugal.

METHODS

This was a multicentric ambispective cohort study including consecutive severe COVID-19 patients between March and August 2020 from 16 Portuguese intensive care units. The peak and plateau periods, respectively, weeks 10 - 16 and 17 - 34, were defined.

RESULTS

Five hundred forty-one adult patients with a median age of 65 [57 - 74] years, mostly male (71.2%), were included. There were no significant differences in median age (p = 0.3), Simplified Acute Physiology Score II (40 versus 39; p = 0.8), partial arterial oxygen pressure/fraction of inspired oxygen ratio (139 versus 136; p = 0.6), antibiotic therapy (57% versus 64%; p = 0.2) at admission, or 28-day mortality (24.4% versus 22.8%; p = 0.7) between the peak and plateau periods. During the peak period, patients had fewer comorbidities (1 [0 - 3] versus 2 [0 - 5]; p = 0.002) and presented a higher use of vasopressors (47% versus 36%; p < 0.001) and invasive mechanical ventilation (58.1 versus 49.2%; p < 0.001) at admission, prone positioning (45% versus 36%; p = 0.04), and hydroxychloroquine (59% versus 10%; p < 0.001) and lopinavir/ritonavir (41% versus 10%; p < 0.001) prescriptions. However, a greater use of high-flow nasal cannulas (5% versus 16%, p < 0.001) on admission, remdesivir (0.3% versus 15%; p < 0.001) and corticosteroid (29% versus 52%, p < 0.001) therapy, and a shorter ICU length of stay (12 days versus 8, p < 0.001) were observed during the plateau.

CONCLUSION

There were significant changes in patient comorbidities, intensive care unit therapies and length of stay between the peak and plateau periods of the first COVID-19 wave.

What changed between the peak and plateau periods of the first COVID-19 pandemic wave? A multicentric Portuguese cohort study in intensive care

OBJECTIVE

To analyze and compare COVID-19 patient characteristics, clinical management and outcomes between the peak and plateau periods of the first pandemic wave in Portugal.

METHODS

This was a multicentric ambispective cohort study including consecutive severe COVID-19 patients between March and August 2020 from 16 Portuguese intensive care units. The peak and plateau periods, respectively, weeks 10 - 16 and 17 - 34, were defined.

RESULTS

Five hundred forty-one adult patients with a median age of 65 [57 - 74] years, mostly male (71.2%), were included. There were no significant differences in median age (p = 0.3), Simplified Acute Physiology Score II (40 versus 39; p = 0.8), partial arterial oxygen pressure/fraction of inspired oxygen ratio (139 versus 136; p = 0.6), antibiotic therapy (57% versus 64%; p = 0.2) at admission, or 28-day mortality (24.4% versus 22.8%; p = 0.7) between the peak and plateau periods. During the peak period, patients had fewer comorbidities (1 [0 - 3] versus 2 [0 - 5]; p = 0.002) and presented a higher use of vasopressors (47% versus 36%; p < 0.001) and invasive mechanical ventilation (58.1 versus 49.2%; p < 0.001) at admission, prone positioning (45% versus 36%; p = 0.04), and hydroxychloroquine (59% versus 10%; p < 0.001) and lopinavir/ritonavir (41% versus 10%; p < 0.001) prescriptions. However, a greater use of high-flow nasal cannulas (5% versus 16%, p < 0.001) on admission, remdesivir (0.3% versus 15%; p < 0.001) and corticosteroid (29% versus 52%, p < 0.001) therapy, and a shorter ICU length of stay (12 days versus 8, p < 0.001) were observed during the plateau.

CONCLUSION

There were significant changes in patient comorbidities, intensive care unit therapies and length of stay between the peak and plateau periods of the first COVID-19 wave.

Perspectives on carbon materials as powerful catalysts in continuous anaerobic bioreactors

The catalytic effect of commercial microporous activated carbon (AC) and macroporous carbon nanotubes (CNT) is investigated in reductive bioreactions in continuous high rate anaerobic reactors, using the azo dye Acid Orange 10 (AO10) as model compound as electron acceptor and a mixture of VFA as electron donor. Size and concentration of carbon materials (CM) and hydraulic retention time (HRT) are assessed. CM increased the biological reduction rate of AO10, resulting in significantly higher colour removal, as compared to the control reactors. The highest efficiency, 98%, was achieved with a CNT diameter (d) lower than 0.25 mm, at a CNT concentration of 0.12 g per g of volatile solids (VS), a HRT of 10 h and resulted in a chemical oxygen demand (COD) removal of 85%. Reducing the HRT to 5 h, colour and COD removal in CM-mediated bioreactors were above 90% and 80%, respectively. In the control reactor, thought similar COD removal was achieved, AO10 decolourisation was just approximately 20%, demonstrating the ability of CM to significantly accelerate the reduction reactions in continuous bioreactors. AO10 reduction to the correspondent aromatic amines was proved by high performance liquid chromatography (HPLC). Colour decrease in the reactor treating a real effluent with CNT was the double comparatively to the reactor operated without CNT. The presence of AC in the reactor did not affect the microbial diversity, as compared to the control reactor, evidencing that the efficient reduction of AO10 was mainly due to AC rather than attributed to changes in the composition of the microbial communities.

Comparison of Retinal Sensitivity between Professional Soccer Players and Non-athletes

The purpose of the study was to compare the peripheral retinal sensitivity of the visual field between professional soccer players and age-gender matched non-athlete subjects. All participants underwent a complete eye evaluation. The visual field was evaluated with the achromatic program 60-4 from the Humphrey automated perimetry. The binocular visual field was created with the best location model. It was divided into 4 quadrants (left superior, right superior, left inferior, and right inferior) and compared between groups. The study group comprised 29 professional male football players and the control group comprised 26 age-matched male non-athletes. Mean age was 25.8±4.7 years in the study group and 26.3±5.1 for controls. The average of retina sensitivity in the left inferior and right inferior quadrants was higher in the study group (27.2±1.2 dB and 27.0±1.4 dB) as compared to controls (26.1±1.9 dB and 25.5±2.1 dB). (Student's t test, P=0.011 and P=0.004, respectively). In this small cohort, professional soccer players presented higher retina sensitivity in the inferior quadrants when compared to non-athletes.

Cyclin D1 expression in prostate carcinoma

The purpose of this study was to investigate the relationship between cyclin D1 expression and clinicopathological parameters in patients with prostate carcinoma. We assessed cyclin D1 expression by conventional immunohistochemistry in 85 patients who underwent radical prostatectomy for prostate carcinoma and 10 normal prostate tissue samples retrieved from autopsies. We measured nuclear immunostaining in the entire tumor area and based the results on the percentage of positive tumor cells. The preoperative prostate-specific antigen (PSA) level was 8.68±5.16 ng/mL (mean±SD). Cyclin D1 staining was positive (cyclin D1 expression in >5% of tumor cells) in 64 cases (75.4%) and negative (cyclin D1 expression in ≤5% of tumor cells) in 21 cases (including 15 cases with no immunostaining). Normal prostate tissues were negative for cyclin D1. Among patients with a high-grade Gleason score (≥7), 86% of patients demonstrated cyclin D1 immunostaining of >5% (P<0.05). In the crude analysis of cyclin D1 expression, the high-grade Gleason score group showed a mean expression of 39.6%, compared to 26.9% in the low-grade Gleason score group (P<0.05). Perineural invasion tended to be associated with cyclin D1 expression (P=0.07), whereas cyclin D1 expression was not associated with PSA levels or other parameters. Our results suggest that high cyclin D1 expression could be a potential marker for tumor aggressiveness.

Protein levels and colony development of Africanized and European honey bees fed natural and artificial diets

Pollen substitute diets are a valuable resource for maintaining strong and health honey bee colonies. Specific diets may be useful in one region or country and inadequate or economically unviable in others. We compared two artificial protein diets that had been formulated from locally-available ingredients in Brazil with bee bread and a non-protein sucrose diet. Groups of 100 newly-emerged, adult workers of Africanized honey bees in Brazil and European honey bees in the USA were confined in small cages and fed on one of four diets for seven days. The artificial diets included a high protein diet made of soy milk powder and albumin, and a lower protein level diet consisting of soy milk powder, brewer's yeast and rice bran. The initial protein levels in newly emerged bees were approximately 18-21 µg/µL hemolymph. After feeding on the diets for seven days, the protein levels in the hemolymph were similar among the protein diet groups (~37-49 µg/µL after seven days), although Africanized bees acquired higher protein levels, increasing 145 and 100% on diets D1 and D2, respectively, versus 83 and 60% in the European bees. All the protein diets resulted in significantly higher levels of protein than sucrose solution alone. In the field, the two pollen substitute diets were tested during periods of low pollen availability in the field in two regions of Brazil. Food consumption, population development, colony weight, and honey production were evaluated to determine the impact of the diets on colony strength parameters. The colonies fed artificial diets had a significant improvement in all parameters, while control colonies dwindled during the dearth period. We conclude that these two artificial protein diets have good potential as pollen substitutes during dearth periods and that Africanized bees more efficiently utilize artificial protein diets than do European honey bees.

[Kommerell diverticula associated with dysphagia: a clinical case and review of the literature]

We report the case of a young female with disphagia and weigth loss caused by a vascular ring associated with right aortic arch, Kommerell diverticula, and left retroesophageal ligamentum arteriosum (ductus arteriosus). The patient underwent surgical treatment. A left thoracotomy was performed. Surgical technique included diverticulum ressection and an aortopexia. There were no major complications. We also discuss the incidence, pathology, diagnosis, clinical features and treatment of this rare disease.

Rationale, design, and analysis of combined Brazilian household budget survey and food intake individual data

Background

Data on food intake at the individual level and its statistical distribution in population groups defined by age, gender, or geographic areas are important in planning public health and nutrition programs. However, individual-based surveys in representative population samples are expensive to perform.

Methods/Design

In Brazil, an individual based survey is under consideration to be conducted alongside the household budget survey (HBS), which will be carried out in 2008–2009. This paper presents the methodological framework of dietary data collection and indicates the directions to combining both sources of data.

The 2008–2009 Brazilian HBS sample will include 60,000 households. Of the selected HBS households, 30% will be randomly sampled to gather data on individual food intake. Therefore, individual dietary intake data is expected to be gathered for 70,000 individuals. Data collection procedures will comprise: completion of a diary with information regarding food purchases during a seven-day period; registration of all items consumed during two non-consecutive days for all 10 year-old or older members of the household. The sample will be large enough to capture the variation between individuals, and the two records will assure the estimation of the variation within individuals for food groups, energy and nutrients. Data on individual dietary intake and food family budget will be stratified by the five regions of the country and by rural or urban. A pilot study has been conducted in two states, and it indicated that combining individual and budgetary data in a survey is feasible.

Discussion

This kind of study will allow us to estimate correlations between individual intake and household purchases, overcoming the limitations of individual dietary surveys, and enhancing the HBS with information on eating out and intra-familiar distribution of food.

["Off pump" coronary surgery and simultaneous carotid endarterectomy]

The occurrence of significant carotid artery disease in patients requiring coronary artery bypass grafting (CABG), results in a dilemma regarding the best surgical management. Our philosophy has been to perform simultaneous carotid endarterectomy and CABG off-pump. We reviewed the efficacy of this therapy in six patients treated in our hospital between January 2001 and December 2002. The result was satisfactory and there was no hospital mortality.

The relationship between parental nutritional status and overweight children/adolescents in Rio de Janeiro, Brazil

BACKGROUND

The association between overweight parents and overweight children/adolescents was investigated in Rio de Janeiro, Brazil between 1995 and 1996, controlling for the influence of socio-economic and demographic factors.

METHODS

Data were obtained from a two-stage, residence-based, random sample survey of children and adolescents aged 6-19 years and their parents. Body mass index (BMI) was used to classify nutritional status. Initially, a logistic regression model was built, using an indicator of parental weight (maternal BMI) as one of the independent variables and the child/adolescent's BMI as the dependent variable. Following that, the association between socio-economic and demographic variables and overweight children/adolescents was analysed in a univariate analysis. These variables were pre-selected for inclusion in the logistic model, provided that their levels of statistical significance were below P=0.25, and were added to the model individually according to the order of association strength in the univariate analysis. Finally, variables were retained in this model at a significance level of P=0.05.

RESULTS

This study found that 20.7% of girls and 26.9% of boys were overweight, with a larger prevalence among children aged less than 9 years. In addition to maternal BMI, the predictors of overweight children and adolescents were age, gender and the number of people in a house.

CONCLUSIONS

These results demonstrate the relationship between maternal nutritional status and overweight children and adolescents, suggesting that obesity-prevention programmes should be focused on the family.

Heavy metals in soft tissues of Tursiops truncatus and Delphinus delphis from west Atlantic Ocean by X-ray spectrometry

In this work, the concentration of heavy metals in muscle, liver, fat tissue and skin is studied in 15 Delphinus delphis and two Tursiops truncatus dolphins, stranded along the Portuguese coast of the Atlantic Ocean. Sample collection was performed post-mortem and the tissues were kept frozen until analysed. Sample preparation included lyophilising and grounding in a Teflon mill to avoid contamination by metals. The obtained powder was prepared as pellets for each sample and analysed directly by X-ray fluorescence spectrometry. The concentrations of K, Ca, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Hg and Pb were obtained. Significant differences between the muscle, the skin and the fat tissues were detected. Cobalt concentrations were similar in liver, skin and muscle. The levels of Ni, Rb and Sr are at the level of the detection limit and whenever measurable are rather constant in all the analysed tissues. The results show that the highest concentrations of Mn, Cu and Hg are always in liver tissues. Zinc and Se concentrations are higher in skin and Pb is present in very low concentrations in all the analysed tissues except in skin; Fe and As are enhanced in muscle and liver. In general, the two studied species did not seem to differ significantly in their heavy metals concentration in a given tissue.

High prevalence of hypertension among Black and Mulatto women in a Brazilian survey

STUDY OBJECTIVES

Brazil has a high admixture of Blacks and Whites, making it possible to compare the prevalence of hypertension among Blacks, Whites, and Mulattos.

DESIGN

A population-based health and nutrition survey was carried out in 1996 in the city of Rio de Janeiro, Brazil. Blood pressure, weight, height, food frequency information, and skin color were obtained from a sample of 2,802 private household residents aged 20 years or older.

MAIN OUTCOME MEASURE

Hypertension was defined as systolic blood pressure >140 mm Hg and/or diastolic pressure >90 mm Hg or the use of antihypertensive medication.

RESULTS

The prevalence of hypertension among men was 12.0% among Whites, 13.8% among Mulattos, and 14.4% for Blacks. For women, these prevalences were 12.0%, 16.4%, and 20.2%, respectively. After adjustment for age, calcium and salt intake, physical activity level, body mass index, and waist-hip ratio, we observed (among women only) a trend toward increasing prevalence of hypertension with increasing skin darkness. The adjusted odds ratio of hypertension was 1.52 for Mulatto women compared to Whites and 2.27 for Blacks compared to Whites (P<.05). With further adjustment for income, the odds ratios were reduced to 1.30 (95% CI 0.86-1.95) and 1.75 (95% CI 1.04-2.94).

CONCLUSIONS

Black women showed increased risk of hypertension independent of socioeconomic factors or overweight status.

[Association between dietary factors and brain tumors in adults: a review]

This paper reviews the scientific literature published from 1986 to 1999 assessing the relationship between dietary factors and brain tumors in adults. The work aimed to describe the estimated associations and to discuss methodological aspects that might influence the results. The studies generally appear to show a moderate association between dietary factors and brain tumors. There is evidence that N-nitroso compounds enhance the risk of developing such tumors and that consumption of fruits and vegetables can inhibit them. Use of proxies in most of the studies may have introduced bias, thereby contributing to some inconsistent observations. Epidemiological research on diet and brain tumors should consider other components of food besides N-nitroso compounds. It is important to carefully assess exposure periods and to prevent bias related to control selection and recall.

Cutting edge: a NK complex-linked locus governs acute versus latent herpes simplex virus infection of neurons

Herpes simplex causes latent infections that periodically reactivate. Specific immunization attempts are failing to control herpes, prompting a fresh look at which host responses predominate. We report a NK complex-linked genetic locus, Rhs1, whose alleles influence the magnitude of experimental herpes simplex. Rhs1 provided rapid control of primary infection but caused a reciprocal increase in the number of latently infected neurons. Thus, in principle, establishment of latency is a consequence of efficient front line defense against herpesvirus infection. Based on conservation between human and mouse NK complexes, the data predict the presence of a human Rhs1 orthologue on chromosome 12p12-13.

Factors associated with overweight and central body fat in the city of Rio de Janeiro: results of a two-stage random sampling survey

The purpose of the survey was to investigate the association of overweight (body mass index, BMI) and central body fat distribution (waist/hip girth ratio WHR) with socio-economic, demographic, lifestyle and dietary variables in the adult population of Rio de Janeiro City, Brazil, 1995-1996. A two-stage random sample population-based survey was performed, with 1455 males and 1906 females above 20 y old resident in Rio de Janeiro City, Brazil. Data were obtained by direct interview and physical examination of the subjects. The intake of selected nutrients (fat, saturated fat, cholesterol) and energy was obtained from a semi-quantitative food frequency questionnaire (FFQ). Variables with at least a marginal univariate association with the dependent variables (BMI and WHR) were selected as predictors in two logistic regression models, and variables statistically significant (P<0.05) were retained in them. Overweight prevalence was 44.9%, and 39.2% of the subjects had excessive central body fat distribution (elevated WHR). The proportions of subjects with an excessive intake of fat, saturated fat and cholesterol were respectively 31%, 42% and 47%. For the BMI model, the variables retained were age (OR=1.5, 95% CI=1.3-1.7), schooling (OR=1.7, 1.4-1.9) and smoking (OR=0.8; 0.7-0.9); and for WHR, age (OR=1.8, 1.5-2.1), schooling (OR=2.2, 1.9-2.6), occupation (OR=1.8, 1.1-2.0) and gender (OR=3.9, 3.2-4.7). Obesity and excessive central body fat are highly prevalent health problems in the studied population. As suggested by the identified risk factors, they should be urgently addressed through health nutrition education and physical activity programs; particularly those directed to the middle aged and female groups.

Upregulation of neuronal amyloid precursor protein (APP) and APP mRNA following magnesium sulphate (MgSO4) therapy in traumatic brain injury

The aim of this study was to assess and quantitate topographically the effects of posttraumatic intravenous magnesium sulphate (MgSO4) on neuronal perikaryal APP antigen and messenger RNA (mRNA) expression in sheep brains 2 h after a controlled focal head impact. The percentage brain area with APP immunoreactive neuronal perikarya was 71, 56, 27.5 and 5.5%, respectively, in MgSO4-treated head-injured animals, head-injured animals without any treatment, MgSO4 treated nonimpacted animals, and nontreated nonimpacted control sheep. Although there was no statistically significant difference in APP immunoreactive neuronal perikarya in the MgSO4-treated HI group (mean 71%) compared to the HI group without any treatment (mean 56%), northern analysis showed that there was a 2.3-+/-0.2-fold increase in APP mRNA in the thalamus of treated impacted animals compared to untreated impacted animals (p < 0.005). However, MgSO4 treated nonimpacted control animals also showed a 1.6-+/-0.1-fold increase in APP mRNA compared to untreated nonimpacted controls (p < 0.005). MgSO4 therapy results in upregulation of neuronal APP mRNA and APP expression that is quantitatively greater following a focal head impact.

Short stature and hypertension in the city of Rio de Janeiro, Brazil

OBJECTIVE

Stature is a powerful indicator of poor nutrition early in life in nations where undernutrition is a public health problem. Hypertension in adults has been associated with factors present early in life such as low birth weight. We tested the hypothesis that short stature is associated with hypertension among adults.

DESIGN AND SETTING

A household survey of representative adults in Rio de Janeiro city, Brazil was carried out in 1996.

SUBJECTS

Blood pressure and anthropometric measures were collected from 2802 adults in their own households. Prevalence estimates and modelling incorporated the sample design and weights.

RESULTS

Age-adjusted prevalence of hypertension for both sexes was lower in the third quartile of stature distribution. In women, but not in men, the odds ratio comparing the first quartile of stature with the fourth quartile was statistically significant with an odds ratio of 1.68 (95%CI 1.02-2.76). Adjusting for known risk factors for hypertension such as age, income, smoking, sodium and alcohol intake and race, the association among women, comparing the first with the fourth quartile for stature, was 1.84 (95%CI 1.03-3.30). With further adjustment for residual of weight on height the ratio reduced to 1.76 (95% CI 0.97-3.19, P value of trend = 0.03). Systolic blood pressure showed a U-shaped association with quartiles of stature, mainly among women, with a beta-coefficient significantly lower at the third quartile.

CONCLUSIONS

This association of stature with hypertension supports the theory of an important ontogenetic dependence of adult blood pressure, at least among women.

Granzyme A, a noncytolytic component of CD8(+) cell granules, restricts the spread of herpes simplex virus in the peripheral nervous systems of experimentally infected mice

Control of ganglionic herpes simplex virus (HSV) infection depends on CD8(+) cells but not on the death of infected neurons. Primarily, perforin and granzyme B mediate CD8(+) cell cytotoxicity, whereas the in vivo functions of granzyme A, a third granule protein, are unknown. Here, it is shown that granzyme A restricts the interneuronal spread of HSV and significantly influences ganglionic virus load.

[Using food frequency questionnaire in past dietary intake assessment]

This paper aims to discuss which one is the best estimator of past diet: a retrospective report or a recent diet recall. The analysis included 13 articles published between 1984-1997 and selected from a MEDLINE search and from other reviews on this subject. The selection criterion was the use of a food frequency questionnaire (FFQ) in a validation study of retrospective report of dietary intake in remote past. Literature review shows that even taking into account misclassification, retrospective report of diet usually yields to a more reliable estimate of past diet pattern than current report. Past diet recall was strongly influenced by current intake and by diet patterns change. Analyzed investigations indicate that agreement between original and retrospective report was higher either for foods eaten rarely or frequently and lower for foods moderately consumed. This review allows considering the FFQ as a valuable instrument when studying the role of diet on the etiology of chronic diseases.

Upregulation of amyloid precursor protein messenger RNA in response to traumatic brain injury: an ovine head impact model

There is evidence that the amyloid precursor protein (APP) plays an important role in neuronal growth and synaptic plasticity and that its increased expression following traumatic brain injury represents an acute phase response to trauma. We hypothesized that the previously described increased APP expression in response to injury (Van den Heuvel et al., Acta Neurochir. Suppl. 71, 209-211) is due to increased mRNA expression and addressed this by examining the expression of APP mRNA and APP within neuronal cell bodies over time in an ovine head impact model. Twenty-five anesthetized and ventilated 2-year-old Merino ewes sustained a left temporal head impact using a humane stunner and 9 normal sheep were used as nonimpact controls. Following postimpact survival periods of 15, 30, 45, 60, and 120 min, brains were perfusion fixed in 4% paraformaldehyde and examined according to standard neuropathological protocol. APP mRNA and antigen expression were examined in 5-microm sections by nonisotopic in situ hybridization and APP immunocytochemistry. The percentage of brain area with APP immunoreactivity within neuronal cell bodies in the impacted animals increased with time from a mean of 7.5% at 15 min to 54.5% at 2 h. Control brains showed only very small numbers of weakly APP-positive neuronal cell bodies ranging from 2 to 14% (mean 7%). Increased expression of APP mRNA was first evident in impacted hemispheres at 30 min after impact and progressively increased over time to involve neurons in all sampled regions of the brain, suggesting increased transcription of APP. In contrast, APP mRNA was undetectable in tissue from nonimpacted sheep. These data show that APP mRNA and antigen expression are sensitive early indicators of neuronal injury with widespread upregulation occurring as early as 30 min after head impact.

Restricted replication of herpes simplex virus in satellite glial cell cultures clonally derived from adult mice

To determine the possible influence of satellite glial cells on restricting the spread of herpes simplex virus in the peripheral nervous system, HSV replication was studied in clonally derived cultures of satellite glial cells from adult animals. Satellite cells were purified by exploiting their close anatomical association with primary sensory neurons. Dissociated neurons from dorsal root ganglia were micro-manipulated to remove all but one of the attached satellite cells and cultured in the presence of the mitogenic stimulators bovine pituitary extract and cholera toxin. Following a lag phase of 20-30 days some of the individual satellite cells began to proliferate. Initial cultures demonstrated bipolar morphology similar to cultured Schwann cells, some of which differentiated into large astrocytic whorl-like cells on subsequent passage. Immunocytochemical and molecular studies demonstrated that these cells, designated Sat.1, express glial fibrillary acidic protein, confirming their glial origin and by electron microscopy they were shown to be phagocytic. Under single step viral growth conditions Sat.1 cells were restrictive for HSV replication, producing in the order of 1000 times less infectious virus than Vero cells, a standard permissive cell line. These results suggest that satellite cells, which tightly encase sensory neurons, play a role in restricting interneural spread of HSV within the peripheral nervous system.

Cell surface expression of H2 antigens on primary sensory neurons in response to acute but not latent herpes simplex virus infection in vivo

CD8(+) T lymphocytes and class I major histocompatibility complex (MHC-I) molecules profoundly influence the severity of neuronal herpes simplex virus (HSV) infection in experimentally infected mice. Paradoxically, neurons are classically regarded as MHC-I deficient. However, it is shown here that H2-encoded heavy chains (alphaCs) and their associated light chain, beta2 microglobulin, are present on the surfaces of primary sensory neurons recovered from sensory ganglia within 1 to 2 weeks of HSV infection. During this time, some neurons are found to be tightly associated with T cells in vivo. Prior data showed that termination of productive HSV infection in the peripheral nervous system is not dependent on cell-mediated lysis of infected neurons. Consistent with these data, immunogold electron microscopy showed that the density of cell surface H2 on neurons is an order of magnitude lower than on satellite glia, which is predicted to favor a noncytolytic CD8 cell response.

[Waist:hips girth ratio as a predictor of arterial hypertension]

This study aims to define cut-off points for the waist:hips girth ratio (WHR), using arterial hypertension as the outcome. The data refer to 3,282 individuals over twenty years of age examined in a survey conducted in the municipality of Rio de Janeiro in 1995-1996, using a two-stage sample. Sixty census tracts were drawn initially; subsequently, 34 households were selected systematically from each tract. Stature, weight, waist and hips girths, and blood pressure were measured in the households. The criterion for hypertension was a systolic blood pressure of ( 140 mmHg or diastolic pressure of ( 90 mmHg, or use of medication to reduce blood pressure. The sensitivity and specificity of different cut-off points for WHR were calculated in the prediction of arterial hypertension according to sex, age, and presence of overweight, classified according to World Health Organization guidelines. The best cut-off points for WHR were 0.95 for men and 0.80 for women. Compared to the waist:stature ratio and waist circumference, the WHR proved more capable of predicting arterial hypertension and less correlated with body mass index.

[Multifactorial analysis of risk factors for low birth weight in Salvador, Bahia]

This study is a multifactorial analysis of the risk factors for low birthweight in a group of newborns in an urban area of Brazil. A total of 1023 infants born in four maternity units in Salvador, Bahia, between July 1987 and February 1988 were included in the study. The sources of information were clinical histories and interviews with the mothers in the maternity units. The analysis was by means of logistic regression. In the final model the risk factors were the following: maternal age less than 21 years or more than 35; gestational age less than 38 weeks; unfavorable outcome of an earlier pregnancy; interval of 12 months or less since prior birth; tobacco smoking; and hypertension. The population attributable risk values for the risk factors included in the final model are presented. These factors should be used to identify pregnant women at high risk of giving birth to a low-birthweight baby, in order to provide them with more prenatal care.

Upregulation of class I major histocompatibility complex gene expression in primary sensory neurons, satellite cells, and Schwann cells of mice in response to acute but not latent herpes simplex virus infection in vivo

Major histocompatibility complex (MHC) deficiency is typical of almost all resident cells in normal neural tissue. However, CD8+ T cells, which recognize antigenic peptides in the context of class I MHC molecules, are known to mediate clearance of herpes simplex virus (HSV) from spinal ganglia of experimentally infected mice, leading to the hypothesis that class I expression in the peripheral nervous system must be upregulated in response to HSV infection. In addressing this hypothesis it is shown, in BALB/c (H-2d) mice, that normally deficient class I transcripts transiently accumulate in peripheral nerve Schwann cells, ganglionic satellite cells, and primary sensory neurons, indicating that in each of these cell types class I expression is regulated at the transcriptional level in vivo. Furthermore, for 3-4 wk after infection, H-2Kd/Dd antigens are expressed by satellite and Schwann cells but not neurons, suggesting additional posttranscriptional regulation of class I synthesis in neurons. Alternatively, the class I RNAs induced in neurons may not be derived from classical class I genes. Factors regulating H-2 class I expression emanate from within infected ganglia, probably from infected neurons themselves. However, induction of class I molecules was not maintained during latency, when viral gene expression in neurons is restricted to a single region within the virus repeats. These data have implications for the long-term survival of cells in HSV-infected neural tissue.

Two subpopulations of human triple-negative thymic cells are susceptible to infection by human immunodeficiency virus type 1 in vitro

Some infants infected with human immunodeficiency virus type 1 (HIV-1) rapidly develop a fatal disease characterized by a severe lymphopenia. To explain the immune dysfunction, we proposed a mechanism by which a nongeneration of CD4+ T cells is caused by HIV-1 infection of thymic cells. To examine this hypothesis, we infected primary triple-negative (TN; phenotypically CD3- CD4- CD8-), CD1a- TN, or CD1a+ TN thymic cell subsets. Our data indicate that by flow cytometry, TN, CD1a- TN, and CD1a+ TN cells remain CD4 negative throughout the culture period. We demonstrated that TN and CD1a+ TN thymic cell subsets are susceptible to HIV-1 as is the entire thymic cell population, whereas CD1a- TN cells are not. A limited number of infected TN cells are expressing HIV-1 but the level of transcription is very high in permissive cells, as detected by in situ hybridization. We then performed blocking experiments on TN cells to examine the mechanism of HIV-1 entry into these cells. CD4 (OKT4a) monoclonal antibody blocks their infection. Finally, infection experiments on two subpopulations of TN cells (CD2+ CD7+ and CD2- CD7-) indicate that infected TN cells may correspond to both immature thymocytes and thymic dendritic cells. These data are of particular interest since infection of thymic stromal cells might result in an impairment of T-cell differentiation, which may explain a nongeneration of functional CD4+ T-cell population in the thymus. This phenomenon may play a role in AIDS pathogenesis, in particular in infants born from seropositive mothers.

Comparison of functional properties of thymic and splenic dendritic cells

Murine dendritic cells (DC) which are negative for surface immunoglobulin (sIg), Fc receptor (FcR), Thy-1 antigen, and the mononuclear phagocyte-specific marker F4/80, but positive for the DC-specific marker 33D1 and major histocompatibility complex (MHC) Class 1 and Class II antigens were obtained from either the spleen (SDC) or thymus (TDC) and used to stimulate alloreactive cytotoxic T lymphocyte (Tc) generation in vitro, in 5-day mixed lymphocyte reaction (MLR) to investigate some of their functional properties. SDC were potent stimulators of Tc cells in the absence of supernatant of concanavalin-A-stimulated spleen cells (CSS) and using medium containing 1% thioglycolate-stimulated mouse serum (TMS) to avoid potential artifactual helper T cell activation by fetal calf serum (FCS) antigens. TDC did not stimulate Tc cells under these conditions, but did so when mixed with small numbers of SDC, or in the presence of CSS. 33D1 and complement (C')-treated SDC and TDC populations failed to stimulate Tc cell responses in the absence of CSS. In the presence of CSS, TDC treated in a similar manner did not stimulate Tc cell activity, while 33D1 and C'-treated SDC stimulated a weak but detectable Tc cell response. These results indicate that genuine DC were the dominant cells presenting Class I MHC antigens in the TDC population and also that a minority of contaminating non-DC in the SDC population expressed sufficient MHC Class I antigens for Tc cell activation, but did not produce factor(s) required for Tc cell activation. The pretreatment of SDC and TDC with CSS before using them as stimulators did not improve their ability to stimulate Tc cell responses, indicating that the effect of CSS in improving the ability of TDC to stimulate Tc cell responses was not solely due to MHC-elevating effects of components of CSS. Lipopolysaccharide (LPS)-treated SDC synthesized abundant interleukin 1 (IL-1), but TDC synthesized low levels of IL-1. Contact for 24 hr between TDC and splenic Tc cell precursors in medium containing 1% TMS but without CSS and FCS did not tolerize the T cells.

Mouse serum as a medium supplement for murine immune responses in vitro

In vitro generation of secondary anti-viral H-2 restricted cytotoxic T cells (Tc cells) alloreactive Tc cells, alloantigen-induced T cell proliferation, bacterial lipopolysaccharide (LPS)-induced B cell proliferation and anti-dinitrophenyl IgM and IgG antibody responses were used to evaluate pools of mouse sera (MS) and other animal sera as medium supplements by comparison with 5-10% fetal calf serum (FCS). Some batches of normal MS were comparable with FCS while others inhibited Tc cell responses when used at 1%, particularly with limiting stimulator cell numbers. In contrast, 2 pools of nude mouse sera and several pools of MS from thioglycollate-injected mice (TMS) used at 1% were consistently comparable with FCS at 5-10% in terms of in vitro generation of effector Tc cells and antibody secreting B cells. TMS at 1% was satisfactory for Tc cell responses either fresh, after heat inactivation at 56 degrees C for 30 min, or after storage for 6 months at -70 degrees C. 0.5% or 2% heat-inactivated rat and rabbit sera (but not guinea pig sera) were also satisfactory for Tc cell generation. Total thymidine incorporation into proliferating B or T cells was 5-15-fold lower in cultures with 1% normal MS, nude MS or TMS than with 5% FCS, but stimulation indices with 1% nude MS and TMS were similar to those with 5% FCS, whereas 1% normal MS apparently completely inhibited stimulation. One percent syngeneic TMS is a convenient, reliable alternative to 5-10% FCS in culture medium, supporting all the murine responses listed above.