Inflammatory cytokines dysfunction in autism spectrum disorder

Introduction

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder. Its underlying causes and pathophysiologies remain unclear. Recent data support the potential involvement of neuroinflammation in the onset of this disorder.

Objectives

The aim of our study was to investigate the potential link between ASD and inflammatory mediators.

Methods

This descriptive study was conducted among ASD outpatients followed-up at the child and adolescent psychiatry department in the Military Hospital of Instruction of Tunis. Blood samples were collected for inflammatory cytokines dosage, notably the interleukin 1β (IL-1β), interleukin 6 (IL-6) and the Tumor Necrosis Factor α (TNF-α) immunodosage.

Results

Twenty-four patients were included in this study, aged between four and ten years old (mean age= 6,55 years; minimum=4; maximum=10 years). Our sample was mainly represented by male patients (95,6%). TNF-α plasmatic levels were high (>5pg/mL) among all of our sample with a mean of 11,6 pg/mL (minimum= 6,87; maximum=17,7 pg/mL; standard deviation= 3,52 pg/mL), suggesting abnormal peripheral blood mononuclear cells response. However, IL-1β and IL-6 plasmatic levels were relatively normal.

Conclusions

An immune response dysregulation was detected in our sample. Multiple clinical and experimental studies investigated the implication of inflammatory cytokines in neurodevelopmental disruption. Their results, however, remain controversial and limited by small samples. Further studies need to be done in order to investigate the neuroimmunological factors linked with ASD.

Screening for adult attention deficit and hyperactivity disorder among military parents: A pilot study

Introduction

The prevalence of adult Attention Deficit and Hyperactivity Disorder (ADHD) has been investigated in the general population by multiple studies. However, few studies have focused on identifying its prevalence in the military population, particularly among military parents of children with ADHD.

Objectives

The aim of our study was to screen for adult ADHD among military parents of ADHD children followed-up at the child and adolescent psychiatry department in the Military Hospital of Instruction of Tunis, Tunisia.

Methods

This prospective study was carried among military parents (one or both parents belonging to the national army) of ADHD children. Children were diagnosed with ADHD based on the 5^th Diagnostic and Statistical Manual ADHD criteria and the Conners Comprehensive Behavior Rating Scale. Whereas adult ADHD was screened for using the Adult ADHD Self-Report Scale-V1.1.

Results

Fifteen children and twenty-nine parents were included in the study: sixteen of the parents were military members and thirteen were civilian spouses. Eight (50%) of the sixteen military parents, and four (30,7%) of the civilian spouses were screened positive for ADHD. Whereas 73% of these children had at least one parent screened positive for ADHD, and 53% had at least one military parent screened positive for ADHD. These results suggest a high prevalence of adult ADHD among this population.

Conclusions

ADHD occurs in childhood and may persist into adulthood. The findings of this study indicate that ADHD symptoms are not limited to the youth and are common in military population. Implications on screening, management, preventive measures and research should be discussed.

The gender distribution of psychopathological disorders at a child and adolescent psychiatry department: About 577 cases

Introduction

The evaluation of the distribution of pathologies according to gender in child and adolescent psychiatry remains an interesting question both for epidemiological and etiopathogenic research.

Objectives

The objective of our work was to study the influence of gender on the psychopathological expression of disorders in children and adolescents.

Methods

A retrospective study was conducted at the outpatient child psychiatry department at the Tahar Sfar University Hospital in Mahdia, Tunisia, among patients who consulted for the first time during the period from January 2015 to December 2017. To carry out this work, we used a pre-established form evaluating the sociodemographic and clinical information. We opted for grouping diagnoses according to axis I of the DSM IV- TR.

Results

We collected 577 cases: 231 girls, and 346 boys. The analysis of the results showed a male predominance (60% of our sample were boys). A significant difference in diagnosis relating to gender was found (p = 0.02). In fact, boys were more likely to have pervasive developmental disorders, mental retardation and externalizing disorders, while girls were more likely to develop sleep and eating disorders and internalizing disorders such as mood disorders.

Conclusions

Demonstrating the existence of a significant gender distribution of pathologies in adolescent and child psychiatry is certainly of real importance in the context of epidemiological, clinical and etiopathogenic research. However, it would be more efficient to further investigate other epidemiological and socio-cultural data in order to better specify the involvement of each of these factors in the emergence of psychopathology.

Predictors of autoimmune hemolytic anemia in beta-thalassemia patients with underlying red blood cells autoantibodies

In beta-thalassemia patients, erythrocyte autoantibodies can remain silent or lead to Autoimmune Hemolytic Anemia (AIHA).The aim of this study was to identify predictors of AIHA in beta-thalassemia patients with positive Direct Antiglobulin Test (DAT), in Tunisia. This longitudinal prognosis study was carried out on beta-thalassemia patients with a positive confirmed DAT. Predictors of AIHA were identified the Kaplan-Meier method. A Cox model analysis was used to identify independent predictors. Among 385 beta thalassemia patients, 87 developed positive DAT (22.6%). Autoimmune hemolytic anemia was occurred in 25 patients. Multivariate analysis showed that AIHA was independently associated with beta-thalassemia intermedia and similar family history of AIHA. Splenectomy in patients with positive DAT was independently associated with an increased risk of AIHA (HR = 6.175, CI: 2.049-18.612, p < 0.001). The risk of developing AIHA was higher during the first 72 transfusions. Autoimmune hemolytic anemia was significantly associated with polyspecific DAT (anti-complement and anti-IgG), blood group AB and prior alloimmunization. Whereas transfusion by phenotypic and leukoreduced blood was a protective factor. In summary, splenectomy after autoimmunization, prior alloimmunization, DAT specificity (IgG with complement), thalassemia intermedia, AB blood group and family history of AIHA were strongly associated with AIHA. Leukoreduced blood transfusion had a proven preventive role.

Second Tunisian case of Anti -Tja mediated recurrent abortions

The diagnosis and the treatment of rare phenotypes remain a problematic situation in many countries especially in Tunisia. Individuals with rare phenotype may develop clinically significant red cell antibodies directed against the high incidence Antigens they lack. A 35 years old patient was referred to our laboratory to explain a high incidence (twelve) of recurrent miscarriage during the first and second terms of pregnancy. This patient was grouped as O Rhesus: 1, -2, -3, 4, 5 K:-1. In her plasma we identified a pan-reactive anti-PP1PK antibody (anti-Tja) recognized to be responsible of spontaneous recurrent abortions. The red cell phenotype was P1 and Tja negative. More investigations concluded to the absence of auto and other allo-antibodies association. Therapeutic plasmapheresis from early stages was suggested for the future pregnancy to remove anti-public antibodies in order to maintain normal placenta functions. The Anti-Tja antibody, naturally occurring in patients with rare p phenotype, has the ability to induce recurrent spontaneous miscarriages and to cause immediate hemolytic transfusion reactions. Despite the absence of compatible donors in her family, this patient is not in an impasse situation because two donors with the same phenotype were identified when investigating a first case in 2013.

The role of access to affordable and quality assured blood and blood products for achieving Universal Health Coverage (Editorial)

The theme of World Health Day 2018 is 'Universal health coverage: everyone, everywhere' under the slogan 'Health for All'. Universal Health Coverage (UHC), as pertains to blood and blood products, means that all individuals and communities have access to affordable and timely supplies of safe and quality-assured blood and blood products. Blood and blood products are essential components in the proper management of women suffering from bleeding associated with pregnancy and childbirth; children suffering from severe anaemia due to malaria and malnutrition; patients with blood and bone marrow disorders and immune deficiency conditions; victims of trauma, emergencies, disasters and accidents; and patients undergoing advanced medical and surgical procedures.

[The JAK2 mutation in myeloproliferative disorders: A predictive factor of thrombosis]

BACKGROUND

BCR-ABL negative myeloproliferative neoplasms (MPN) include polycythemia Vera (PV), essential thrombocythemia (ET) and primitive myelofibrosis (PMF). the JAK2 V617F mutation has been introduced since 2008 as a major diagnostic criterion on the one hand and on the other hand, it would be linked to increased risk of thrombotic complications.

AIM

This study aimed to evaluate the association of JAK2 mutation and thrombotic events in MPN.

METHODS

A retrospective study concerning 45 BCR-ABL negative MPN patients (mean age=53 old years, sex ratio=0.8) was conducted.

RESULTS

They were classified as PV (22 patients), ET (17 patients), PMF (3 patients) and atypical MPN (3 patients). The JAK2 mutation was found in 64.4% of patients: 72.7% of PV patients, 47% of ET patients and 66.7% of PMF patients. Thrombotic events were recorded in 11 patients (24.4%). Cerebral arteries and portal vein were the most frequent localizations. The JAK2 mutation was an independent risk factor of thrombotic events.

CONCLUSION

Consequently, it seems that screening for JAK2 mutation in BCR-ABL negative MPN could play a role in identifying patients at high risk of vascular complications.

Behavioral and neurophysiological study of attentional and inhibitory processes in ADHD-combined and control children

This study compares behavioral and electrophysiological (P300) responses recorded in a cued continuous performance task (CPT-AX) performed by children with attention deficit hyperactivity disorder-combined subtype (ADHD-com) and age-matched healthy controls. P300 cognitive-evoked potentials and behavioral data were recorded in eight children with ADHD (without comorbidity) and nine control children aged 8-12 years while performing a CPT-AX task. Such task enables to examine several kinds of false alarms and three different kinds of P300 responses: the "Cue P300", the "Go P300" and the "NoGo P300", respectively, associated with preparatory processing/attentional orienting, motor/response execution and motor/response inhibition. Whereas hit rates were about 95% in each group, ADHD children made significantly more false alarm responses (inattention- and inhibition-related) than control children. ADHD children had a marginally smaller Cue P300 than the control children. Behavioral and electrophysiological findings both highlighted inhibition and attention deficits in ADHD-com children in the CPT-AX task. A rarely studied kind of false alarm, the "Other" FA, seems to be a sensitive FA to take into account, even if its interpretation remains unclear.

Prospective randomised comparison of the COBE Spectra version 6 and Haemonetics MCS+ cell separators for hematopoietic progenitor cells leucapheresis in patients with multiple myeloma

A randomised crossover trial of two separators was undertaken to compare the mononuclear cell, CD34(+) cell and CFU-GM yield, in patients (<61 years) with previously untreated symptomatic multiple myeloma. After first-line therapy, all patients received mobilising chemotherapy (cyclophosphamide 4 g/m(2)) and daily G-CSF. The first leucapheresis was performed on the first day the peripheral blood absolute CD34(+) cell count was > 20 cells/microl. All patients underwent 2 leucaphereses on consecutive days. The patients were randomised to undergo either the first or second leucapheresis using the COBE Spectra. The target duration of the procedure on the COBE Spectra was 2 total blood volumes, and for the Haemonetics MCS(+) it was 20 cycles with four recirculations. Between September 2003 and March 2005, 60 patients were entered in the study. COBE Spectra version 6 processed significantly larger volumes of blood than the Haemonetics MCS(+) (8,845 and 5,680 ml, respectively, P < 0.01). The absolute yield of mononuclear cells (2.1 vs. 1.5 x 10(8)/kg, P = 0.04), CFU-GM (11 vs. 3 x 10(4)/kg, P = 0.01) and CD34(+) cells (3 vs. 1.7 x 10(6)/kg, P = 0.02) were all significantly higher with the COBE Spectra version 6, as were the yields per unit volume of blood processed. In conclusion, our study shows that COBE Spectra Version 6 is faster and has a better yield than the Haemonetics MCS(+), in patients with multiple myeloma.

Frontotemporal dementia progresses to death faster than Alzheimer disease

BACKGROUND

Frontotemporal lobar degeneration (FTLD) is a common cause of non-Alzheimer dementia, but its natural history and the factors related to mortality in affected patients are not well understood.

METHODS

This retrospective, longitudinal study compared survival in FTLD (n = 177) with Alzheimer disease (AD; n = 395). Hazards analysis investigated the contribution of various demographic, neuropsychiatric, and neuropsychological variables and associated neurologic and neuropathologic findings.

RESULTS

The frontotemporal dementia (FTD) subtype of FTLD progressed faster than AD (median survival from retrospectively determined symptom onset, 8.7 +/- 1.2 vs 11.8 +/- 0.6 years, p < 0.0001; median survival from initial clinic presentation, 3.0 +/- 0.5 vs 5.7 +/- 0.1 years, p < 0.0001). Survival was similarly reduced in the related conditions corticobasal degeneration and progressive supranuclear palsy. Survival in the semantic dementia subtype of FTLD (11.9 +/- 0.2 years from onset and 5.3 +/- 0.4 years from presentation), however, was significantly longer than in FTD and did not differ from AD. Hazards analysis to determine factors affecting survival in FTLD showed no effect of age at onset, sex, education, family history, or neuropsychiatric profile. Among neuropsychological measures examined, impaired letter fluency had a significant association with reduced survival. Associated ALS significantly reduced survival in FTLD. The presence of tau-positive inclusions was associated with the slowest progression.

CONCLUSIONS

Frontotemporal lobar degeneration progresses more rapidly than Alzheimer disease, and the fastest-progressing cases are those with the frontotemporal dementia clinical subtype, coexisting motor neuron disease, or tau-negative neuropathology.

The French Addenbrooke's cognitive examination is effective in detecting dementia in a French-speaking population

We evaluated the sensitivity and specificity of our French version of Addenbrooke's cognitive examination (ACE) to detect dementia in our patient population. One hundred and fifty-eight cases were included in the study. In our patient series, the sensitivity for diagnosing dementia with a Mini-Mental State Examination (MMSE) score of < or = 24/30 was 48.5%, the sensitivity of an MMSE score of < or = 27/30 was 82.5% with a specificity of 72.1%, the sensitivity of an ACE score of < or = 83/100 was 86.6% with a specificity of 70.5% and the sensitivity of an ACE score of < or = 88/100 was 97.9% with a specificity of 59%. We conclude that the French version of the ACE is a very accurate test for the detection of dementia, and should be widely used in clinical practice.

Fanconi anemia: contribution of molecular analyses to the identification of bone marrow graft donors and the study of chimerism in grafted patients

We report on the effectiveness of molecular studies regarding Fanconi anemia (FA) for a better selection of bone marrow graft donors and for post-transplant follow up. Ten unrelated FA patients and their families were analyzed by microsatellite markers. In 9 cases, the cytogenetic investigation of potential human leukocyte antigen (HLA)-identical related donors was normal, and the molecular analyses confirmed that they were also either normal or heterozygous carriers. For 1 patient, cytogenetic analysis of an HLA-identical sibling donor yielded ambiguous results with a relatively high number of chromosomal breakages using cross-linking agents. However, genotyping of this potential donor demonstrated his heterozygous state. Nine patients have received allogeneic bone marrow transplantation from HLA-matched related donors. Microsatellite analysis showed complete chimerism (CC) in all cases. The median follow up was 54 months (range 8-144 months). One patient out of 9 with CC rejected her graft without prior detection of a transitional mixed chimerism. Among these patients, 1 died 25 months after the transplantation of a chronic graft-versus-host-disease (GVHD). We conclude that, when the cytogenetic studies are not conclusive, molecular analyses are crucial to distinguish heterozygous carriers from asymptomatic FA Tunisian patients. Molecular analyses also allowed the evaluation of hematopoietic chimerism after allogeneic bone marrow transplantation and might be of value to identify patients with a high risk for graft rejection.

Is the Addenbrooke?s Cognitive Examination effective to detect frontotemporal dementia?

We evaluated the Addenbrooke's cognitive examination (ACE), a simple instrument to differentiate frontotemporal dementia (FTD) from Alzheimer's disease (AD), in our dementia patients clinic population. The Verbal-Language/Orientation-Memory (VLOM) ratio, which compares its language and memory scores, determines whether FTD or AD is more likely. The ACE was translated into French with adaptation maintaining the number of words in the name and address learning and delayed recall test, and with cultural adaptation for the semantic memory. The 85 included subjects had no evidence of two or more organic pathologies, after at least six months of follow-up, and an MMSE score>or=20/30. Patients with cognitive impairment due to alcohol intake were excluded. The diagnosis of a specific dementing illness was based on the consensus of the neurologist and neuropsychologists in the team. Thereafter, another neurologist expert in dementia, blinded to the ACE result and to the diagnosis and treatment, reviewed all cases files and proposed a diagnosis. A diagnostic agreement was reached for 79 cases (92.9%) with 40 (50.6%) dementia: 25 AD (62.5 %), 9 FTD (22.5 %). We estimated that the sensitivity for detecting dementia of an ACE score<or=83/100 was 90% with a specificity of 64.1%. When the ACE score was<or=88/100, the sensitivity for diagnosing FTD of a VLOM ratio<2.2 was 11.1% with a specificity of 88 % and the sensitivity for diagnosing AD of a VLOM ratio>3.2 was 72%,with a specificity of 69.4%. We conclude that, when used as originally proposed, ACE is very accurate for the detection of dementia, but much less effective in discriminating the most common frontal variant of FTD.

Control of in vitro prostaglandin F2 alpha and E2 synthesis by caruncular and allantochorionic tissues from cows that calved normally and those with retained fetal membranes

High concentrations of PGF2 alpha and PGE2 are produced by the uterus during the early postpartum period in cows and may play an important role in both placental separation and uterine involution. In the present study, we have examined the hormonal and intracellular control mechanisms involved in PGF2 alpha and PGE2 secretion by caruncular and allantochorionic tissue in vitro. Tissue explants, obtained about 6 hr postpartum from cows that delivered normally (NFM, n = 10) or cows with retained fetal membranes (RFM, n = 4), were incubated for 6 hr and PGF2 alpha and PGE2 concentrations in the medium were determined by radioimmunoassay. Addition of oxytocin (100 microU/ml), platelet activating factor (PAF, 100 ng/ml) and epidermal growth factor (EGF, 100 ng/ml) had no effect on secretion of PGF2 alpha from the caruncle, but oxytocin and PAF did stimulate PGE2. There was no difference between groups of cows. All three substances stimulated PGF2 alpha from the allantochorion of NFM, but not RFM, cows and stimulated PGE2 secretion from the allantochorion of both groups of cows. Incubation of the tissues with cholera toxin (100 ng/ml), dibutyryl cyclic adenosine 3',5'-monophosphate (dibutyryl cAMP, 1 mM), calcium ionophore A23187 (5 microM) or phorbol ester 12-myristate-13 acetate (PMA, 100 nM) showed that PGF2 alpha secretion is essentially via the calcium-protein kinase C effector pathway. However, calcium-protein kinase C and cAMP second messenger systems appear to be involved in the secretion of PGE2. Prostaglandin secretion was sensitive to cycloheximide in both caruncular and allantochorionic tissues, suggesting that protein synthesis may be involved. In conclusion, these data show that in vitro PGF2 alpha secretion can be modulated by the agonists used only in allantochorion and is essentially via the calcium-protein kinase C effector pathway. PGE2 secretion can be modified in both caruncular and allantochorion tissues and involves both inositol triphosphate-diacylglycerol and cAMP second messenger systems.

Effect of bacterial cell wall and lipopolysaccharide on arachidonic acid metabolism by caruncular and allantochorionic tissues from cows that calved normally and those that retained fetal membranes

Immunoactive eicosanoids may have a role in both placental separation and uterine involution in cattle. In the present study, we examined the effects of bacterial cell wall preparation and endotoxins on in vitro prostaglandin synthesis and arachidonic acid (AA) metabolism by caruncular and allantochorionic tissues. Placentomes were obtained about 6 h post partum from cows that delivered normally (n = 10) or those with retained fetal membranes (n = 4); the tissue explants were incubated for 6 h in the presence of labeled or nonlabeled AA. Prostaglandin F(2alpha) (PGF(2alpha)) and E(2) (PGE(2)) were measured by radioimmunoassay, and labeled AA metabolites were separated by reverse phase-high pressure-liquid chromatography. There was no effect of bacterial cell wall preparations or endotoxins on in vitro caruncular PGF(2alpha) secretion. However, bacterial products increased caruncular PGE(2) secretion in both cows that delivered normally and those with retained fetal membranes. For normal delivery cows caruncular tissue, bacterial product also increased leukotriene B(4) (LTB(4)) and decreased both thromboxane B(2) (TXB(2)) and hydroxy-eicosatetranoic acids (HETE) in vitro secretion. For the allantochorion, bacterial products increased in vitro PGF(2alpha) secretion only in cows that delivered normally and increased PGE(2) secretion essentially in cows with retained fetal membranes. In general, 6 keto PGF(1alpha) was the main metabolite secreted by both allantochorionic and carucular tissues. However, in cows with retained fetal membranes, PGE(2) became the most important metabolite secreted by allantochorion, especially in the presence of endotoxin. In conclusion, these results suggest that bacteria found in the early postpartum uterus or their endotoxin affect primarily caruncular and allantochorionic PGE(2) synthesis.

[Quantitative assessment of the quality of life of patients with a kidney transplant]

Actually three methods are offered for the treatment of patients with chronic renal failure: 1. Hemodialysis, 2. chronic peritoneal dialysis for outpatients (CAPD) and 3. Transplantation of a kidney. In order to define the optimal therapy for these patients not only economic factors but also quantitative evaluation of life quality has to be taken into account. To this end a questionnaire called "Sickness Impact Profile", that covers most of the relevant features of life and is well established in the Anglo-Saxon countries, was translated into German language and tested in 34 hemodialysis-patients, 25 CAPD-patients and 29 patients with kidney transplant, in order to investigate the applicability. Results showed that the German issue can successfully be applied to Swiss patients with renal failure and lead to the conclusion that--in accordance to results of similar studies in the USA--life quality in patients with kidney transplant is better than in patients treated with hemodialysis or CAPD.

Leukotriene B4 in cows with normal calving, and in cows with retained fetal membranes and/or uterine subinvolution

Two experiments were performed to study the relationship between leukotriene B4 (LTB4) synthesis and placental separation and uterine involution in the cow. In experiment I, the concentration and synthesis of LTB4 by caruncular tissue was lower in cows with retained fetal membranes (RFM cows, n = 11) than in cows that expelled the fetal membranes normally (NFM cows, n = 19). The presence of bacterial cell wall, especially of alpha-hemolytic streptococci and coagulase positive staphylococci enhanced LTB4 synthesis by allantochorion only in NFM cows. In the RFM group, Escherichia coli lipopolysaccharide decreased allantochorionic LTB4 synthesis. With caruncle, only epidermal growth factor increased LTB4 production in NFM cows. In experiment II, the caruncular and endometrial secretion of LTB4 was lower in cows with subuterine involution (SUI cows, n = 5) or cows with SUI and RFM (SUI+RFM cows, n = 4) than in cows with normal uterine involution (NUI cows, n = 8). This decrease was especially noticeable in the previously gravid horn. In the three uterine involution groups, there were no differences in LTB4 synthesis by caruncular tissue taken from the previously gravid horn. However, progesterone and a bacterial suspension of E. coli reduced the synthesis of LTB4. Estradiol had no effect on LTB4 synthesis at the end of the postpartum period. These results suggest that LTB4 may play an important role in both placental separation and uterine involution in cattle and LTB4 synthesis may be modulated by endocrine and bacterial factors.

Metabolism of arachidonic acid by caruncular and allantochorionic tissues in cows with retained fetal membranes (RFM)

The metabolism of arachidonic acid (AA) by caruncular and allantochorionic tissues and its regulation was studied in normal cows (n = 13) and those with retained fetal membranes (RFM; n = 9). Tissues were taken via the vagina about 6 hours postpartum and incubated for 6 hours in minimum essential medium containing tritiated AA alone or in the presence of oxytocin, platelet activating factor (PAF), epidermal growth factor (EGF) or ionophore calcium (A23187). The metabolites of AA were separated by reverse phase-high pressure-liquid chromatography. Tissue concentrations of prostaglandin F2 alpha (PGF2 alpha) and prostaglandin E2 (PGE2) and plasma 13,14-dihydro-15-keto-PGF2 alpha (PGFM) concentration were also measured by radioimmunoassay. For caruncular tissue, less thromboxane B2 (TXB2) and more 6-keto prostaglandin F1 alpha (PGIM) was synthesized in tissue from the animals with RFM than in the controls. Oxytocin, PAF, EGF and A23187 increased only PGIM production in the control animals; A23187 also decreased TBX2 synthesis. For the allantochorion, more PGE2, leukotriene B4 (LTB4) and PGIM and less TXB2, PGF2 alpha and hydroxyecosatetranoic acids (HETE) was synthesized in tissue from cows with RFM than from animals that delivered normally. All of the substances used in this study increased PGIM, PGF2 alpha and LTB4 and decreased TXB2 production by the allantochorionic tissue in control animals. The metabolism of AA by the allantochorionic tissue seems quantitatively under hormonal control. The metabolism of AA at the level of both maternal and fetal components of the placenta in cows with RFM differed from that seen in animals that expelled the membranes normally.

[Epidemiologic study of anti-HCV antibodies in Tunisian blood donors]

A study carried out on 2,006 Tunisian blood donors permitted us to evaluate the prevalence of hepatitis C virus antibodies (anti-HCV) which was 1.09%; frequency of indirect markers of NANBH were as follows: ALAT greater than 2 N (1.24%), anti-HBc (30.35%), 55.5% of HCV (+) donors had anti-HBc (+), 12.5% had rises ALAT and only 33.3% both markers.

A versatile hydraulically operated respiratory servo system for ventilation and lung function testing

A description is given of the design and performance of a microcomputer-controlled respiratory servo system that incorporates the characteristics of a mechanical ventilator and also allows the performance of a multitude of test procedures required for assessment of pulmonary function in paralyzed animals. The device consists of a hydraulically operated cylinder-piston assembly and solenoid valves that direct inspiratory and expiratory gas flow and also enable switching to different test gas sources. The system operates as a volume-flow-preset ventilator but may be switched to other operational cycling modes. Gas flow rates may be constant or variable. The system operates as an assister-controller and, combined with a gas analyzer, can function as a "demand" ventilator allowing for set-point control of end-tidal PCO2 and PO2. Complex breathing maneuvers for a variety of single- and multiple-breath lung function tests are automatically performed. Because of the flexibility in selection and timing of respiratory parameters, the system is particularly suitable for respiratory gas studies.