Attitude of Dutch hospital personnel towards influenza vaccination

In 2007, the Dutch Health Council recommended influenza vaccination of all institutional healthcare workers (HCWs). In this questionnaire study largely based on the health belief model we assessed the attitude and intentions of hospital personnel towards such vaccination. We sent out 220 questionnaires to medical personnel and nurses of departments of the University Medical Center Utrecht, The Netherlands. Only one-third of the 112 responders (response rate of 51%) reported a positive intention to comply with the national recommendation. Factors associated with a positive intention were the awareness of a HCW's responsibility not to harm patients, the belief to have a high risk of influenza infection and confidence in vaccine efficacy. Physicians were more likely than nurses and other staff to have a positive intention. Education is needed to convince hospital personnel about influenza vaccination.

Pneumococcal vaccines for preventing otitis media

BACKGROUND

Acute otitis media (AOM) is one of the most common diseases in early infancy and childhood. Long term effects of recurrent episodes of otitis media, rapid emergence of drug resistant bacteria associated with AOM worldwide and huge estimated direct and indirect annual costs associated with otitis media have emphasized the need for an effective vaccination program to prevent episodes of AOM.

OBJECTIVES

The object of this review was to assess the effect of pneumococcal vaccination in preventing AOM in children up to 12 years of age.

SEARCH STRATEGY

We searched the Cochrane Acute Respiratory Infection Group specialised register (last update, 26th April 2001), the Cochrane Library (Issue 4, 2000), MEDLINE (January 1966-August 2000) and reference list of all studies and review articles retrieved. We also contacted two vaccine manufacturers and first or corresponding authors of some included studies.

SELECTION CRITERIA

Randomised controlled clinical trials of pneumococcal vaccination with prevention of AOM as outcome in children aged 12 years or younger and a follow-up of at least six months.

DATA COLLECTION AND ANALYSIS

Five reviewers independently assessed trial quality and two reviewers extracted data. Two study authors were contacted.

MAIN RESULTS

Eight trials on pneumococcal polysaccharide vaccine (PPV) and two trials on pneumococcal conjugate vaccine (PCV) were included. The highest efficacy of PPV was found in children aged 24 months and older: the rate ratio after adjustment for study was 0.833 [95%CI: 0.625-0.970]. The PPV has little effect on the prevention of AOM in children without documented prior episodes of AOM and only a moderate effect in the group of children with documented AOM episodes prior to vaccination. The results of the two PCV trials in healthy infants, which followed children from the age of two months until two years of age, could not be pooled because of lack of data. Both studies showed that the risk of recurrent disease decreased with 9% in the group of children receiving the PCV together with other childhood vaccinations at 2,4,6 and 14 months of age: Study Black et al 2000 : risk ratio=0.91[95%CI:0.86-0.96]; Study Eskola et al 2001: risk ratio=0.90 [95%CI:0.73-1.12].

REVIEWER'S CONCLUSIONS

Based on the currently available results of the effectiveness of pneumococcal vaccination for the prevention of AOM, a large scale use of pneumococcal vaccination for this indication is not recommended. The results of currently ongoing trials could provide more information whether pneumococcal vaccines are effective in specific high-risk (otitis-prone) populations.

Glycine antagonist (GV150526) in acute stroke: a multicentre, double-blind placebo-controlled phase II trial

GV150526 is a novel glycine antagonist at the NMDA receptor complex. It is a potent neuroprotective agent in animal models of acute stroke including permanent middle cerebral artery occlusion in the rat. GV150526 was very well tolerated in early human studies. The purpose of this randomised, double-blind, multicentre, placebo-controlled trial was to assess the safety and population pharmacokinetics of GV150526 in patients with a clinical diagnosis of acute stroke. Exploratory assessment of efficacy, quality of life and resource utilisation was also undertaken. Upon clinical diagnosis of acute stroke within 12 h of onset of symptoms, patients were treated with a loading dose of 800 mg GV150526 (or placebo), followed by 5 maintenance doses of 400 mg GV150526 (or placebo) given every 12 h over 3 days. Following observation of asymptomatic hyperbilirubinaemia, the maintenance dose was reduced mid-study to 200 mg. CT/MRI scanning was not mandatory prior to treatment. The study treated 128 patients (38 with GV 800 mg/400 mg, 48 with GV 800 mg/200 mg and 42 with placebo). Fewer patients with mild stroke (NIH scores < or =5) were enrolled in the GV150526-treated groups than in the placebo group (placebo 38%, GV 800 mg/400 mg 18%, GV 800 mg/200 mg 15%). There was also an imbalance in the proportion of patients with haemorrhagic strokes (placebo 5%, GV 800 mg/400 mg 3%, GV 800 mg/200 mg 15%). Mortality at 1 month was unbalanced between treatment groups, being 10, 18 and 17% in the placebo, GV 800 mg/400 mg and GV 800 mg/200 mg groups, respectively (no significant difference). Similarly, adverse events, though consistent with an acute stroke population, appeared more often in the GV 800 mg/200 mg group. Functional outcomes at 1 month also showed imbalances, the percentage of patients with a Barthel Index score of > or =95 at 1 month being 52, 39 and 27% in the placebo, GV 800 mg/400 mg and GV 800 mg/200 mg groups, respectively. These results probably reflect a prognostically significant baseline difference between the groups rather than the effect of GV150526. GV150526 was generally well tolerated in patients with a clinical diagnosis of acute stroke and formal efficacy studies were considered justified.

[Vaccination against acute otitis media]

Acute otitis media (AOM) is the most frequent bacterial infection in childhood. Because of the high morbidity, the costs of AOM and growing concern about increasing resistance of pneumococci, the most common bacterial cause of AOM, prevention of AOM is important. Vaccination with the recently developed pneumococcal conjugate vaccines leads to a reduction in the number of AOM cases caused by the serotypes present in the vaccine, but the reduction in overall AOM incidence is below 10%. In particular the children with recurrent episodes of AOM may benefit more from these pneumococcal conjugate vaccines.

[Immunology in medical practice. XVIII [correction of XVII]. Children with recurrent airway problems: asthma is not always the cause

Three children, two boys aged 16 and 11 years and a girl aged 16 years, with symptoms resembling asthma had been treated for years with inhaled corticosteroids and beta 2-sympathicomimetics without satisfactory results. It was found that the antibody production after vaccination with 23-valent pneumococcal vaccine was impaired. The symptoms diminished during maintenance treatment with antibiotics in two children and with intravenous immunoglobulins in one. In patients with recurrent respiratory problems, but no specific history of asthma, immunological investigation is warranted, especially in patients whose 'asthma' is accompanied by respiratory infections. When treated for their immunodeficiency these patients show remarkable improvement and the need for steroids often disappears.

[Too old for a lumbar hernia operation]

Three patients, one male aged 81 and two females aged 77 and 81, showed a lumbar disc herniation at CT-scan and caudographic examination. Because conservative treatment was unsuccessful and their premorbid health was good, it was decided to perform an operation. All subjects recovered completely, there were no surgical complications. In patients over the age of 70 showing signs and symptoms of nerve root compression one should consider disc herniation. If this is found, surgery is a reliable option despite advanced age. Pre- operative health state is determinative for the decision whether or not to operate on patients of advanced age.

Infant B cell responses to polysaccharide determinants

Newborns and infants up to the age of 1.5-2 years of age are unable to produce antibodies to bacterial capsular polysaccharides. As a consequence, children up to the age of 2 years have an increased susceptibility for infections with encapsulated bacteria. Capsular polysaccharides are classified as so-called T cell independent type 2 antigens and induce IgG2 antibodies. The mechanism of B lymphocyte activation by polysaccharides differs from that of protein antigens and involves co-stimulation by CD21 (type 2 complement receptor). Reduced expression of CD21 on neonatal B lymphocytes can explain unresponsiveness to polysaccharides. Polysaccharide protein conjugates have the ability to overcome unresponsiveness to polysaccharides early in life. The response induced is predominant IgGl.

[Invasive infection with Haemophilus influenzae type b in spite of complete vaccination]

Five patients, 4 boys and 1 girl aged 13-41 months, developed invasive Haemophilus influenzae type b (Hib) disease (2 epiglottitis, 3 meningitis) despite full (or at least 3 times) vaccination. At admission as well during convalescence, 3 out of 5 had IgG anti Hib antibody levels < or = 5 U/ml. Serum immunoglobulin levels, including IgG subclasses, as well as complement were normal in all cases. In 2 of the 3, booster vaccinations with Hib conjugate vaccine elicited adequate antibody titres. Since the incorporation of the conjugated Hib polysaccharide tetanus toxoid vaccine (HibTT) in the National Vaccination Programme in the Netherlands, the number of invasive infections caused by Hib has dropped significantly. Causes of Hib conjugate vaccine failures are mostly unknown. In about one-third of the cases serum immunoglobulin levels are deficient, most often IgG2 or IgM. Susceptibility to Hib infection is in part also genetically determined. In the follow-up of Hib vaccine failures, anti Hib antibody titres should be determined. Booster vaccinations may be necessary.

[Immunology in clinical practice. XI. IgG receptors: the role of polymorphism in autoimmune and infectious diseases]

Receptors for the constant part of IgG (Fc gamma R) are implicated in the pathogenesis of a number of diseases. Children from mothers with an Fc gamma RIIIb deficiency may suffer from neonatal neutropenia due to an alloimmune reaction. Interindividual differences (polymorphisms) for a number of Fc gamma R represent risk factors for several infectious and autoimmune diseases. Immunotherapeutic use of several monoclonal antibody subclasses is affected by Fc gamma R polymorphisms. Fc gamma R can be used for cellular entrance by lymphotropic viruses (such as HIV) and appear to be involved in the pathogenesis of fulminant Dengue virus infections.

Clinical spectrum of X-linked hyper-IgM syndrome

We report the clinical and immunologic features and outcome in 56 patients with X-linked hyper-IgM syndrome, a disorder caused by mutations in the CD40 ligand gene. Upper and lower respiratory tract infections (the latter frequently caused by Pneumocystis carinii), chronic diarrhea, and liver involvement (both often associated with Cryptosporidium infection) were common. Many patients had chronic neutropenia associated with oral and rectal ulcers. The marked prevalence of infections caused by intracellular pathogens suggests some degree of impairment of cell-mediated immunity. Although lymphocyte counts and in vitro proliferation to mitogens were normal, a defective in vitro proliferative response to antigens was observed in some patients, and additional defects of cell-mediated immunity may be presumed on the basis of current knowledge of CD40-ligand function. All patients received regular infusions of immunoglobulins. Four patients underwent liver transplantation because of sclerosing cholangitis, which relapsed in there. Three patients underwent bone marrow transplantation. Thirteen patients (23%) died of infection and/or liver disease. X-linked hyper-IgM syndrome, once considered a clinical variant of hypogammaglobulinemia, is a severe immunodeficiency with significant cellular involvement and a high mortality rate.

The risk of brain tumours in hereditary non-polyposis colorectal cancer (HNPCC)

Hereditary non-polyposis colorectal cancer (HNPCC) is known to be associated with several extracolonic cancers, e.g., cancers of the endometrium, stomach, urinary tract, small bowel and ovary. An association between HNPCC and brain tumours has also been reported, although previous risk analysis did not reveal an excess of this type of tumour. To determine whether HNPCC predisposes patients to brain tumours, we used risk analysis to compare families with HNPCC to those in the general population. Of the 1,321 subjects from 50 HNPCC families (with 60,237 person-years of follow-up) in the Dutch HNPCC Registry which satisfy the Amsterdam Criteria, 312 had colorectal cancer. The registry revealed 14 brain tumours in the HNPCC-patients and their first-degree relatives: 5 astrocytomas, 3 oligodendrogliomas, 1 ependymoma and 5 tumours for which a pathological report was not available. The relative risk of brain tumour in patients with HNPCC and their first-degree relatives was 6 times greater than in the general population (95% confidence interval, 3.5 to 10.1). After exclusion of the cases based only on family history, the relative risk was 4.3 (95% confidence interval, 2.3 to 8.0). Although the relative risk of brain tumour was increased, the lifetime risk was low (3.35%). Because it is not certain whether an improvement of the overall prognosis can be achieved by early diagnosis and intervention, and in view of the low lifetime risk, we do not recommend screening for brain tumours in HNPCC families.

The risk of brain tumours in hereditary non-polyposis colorectal cancer (HNPCC)

Hereditary non-polyposis colorectal cancer (HNPCC) is known to be associated with several extracolonic cancers, e.g., cancers of the endometrium, stomach, urinary tract, small bowel and ovary. An association between HNPCC and brain tumours has also been reported, although previous risk analysis did not reveal an excess of this type of tumour. To determine whether HNPCC predisposes patients to brain tumours, we used risk analysis to compare families with HNPCC to those in the general population. Of the 1,321 subjects from 50 HNPCC families (with 60,237 person-years of follow-up) in the Dutch HNPCC Registry which satisfy the Amsterdam Criteria, 312 had colorectal cancer. The registry revealed 14 brain tumours in the HNPCC-patients and their first-degree relatives: 5 astrocytomas, 3 oligodendrogliomas, 1 ependymoma and 5 tumours for which a pathological report was not available. The relative risk of brain tumour in patients with HNPCC and their first-degree relatives was 6 times greater than in the general population (95% confidence interval, 3.5 to 10.1). After exclusion of the cases based only on family history, the relative risk was 4.3 (95% confidence interval, 2.3 to 8.0). Although the relative risk of brain tumour was increased, the lifetime risk was low (3.35%). Because it is not certain whether an improvement of the overall prognosis can be achieved by early diagnosis and intervention, and in view of the low lifetime risk, we do not recommend screening for brain tumours in HNPCC families.

Surgical repair of traumatically induced collapsing trachea in an ostrich

A region of tracheal collapse was identified by endoscopy after surgical repair of a traumatic injury to the neck in an ostrich. During periods of excitation, the ostrich would become dyspneic and collapse. A tracheal split-ring prosthesis was placed surgically to support the collapsing trachea. This technique, which is frequently used in dogs, is applicable for use in birds with collapsing trachea.

Varicella-zoster virus assembly protein p32/p36 is present in DNA-containing as well as immature capsids

Varicella-zoster virus (VZV) produces a group of nucleocapsid proteins (the p32/p36 nucleoprotein complex) which are the VZV analogues of the herpes simplex virus type 1 (HSV-1) and cytomegalovirus (CMV) assembly proteins. There are multiple components in the VZV p32/p36 complex, with major proteins of 32 and 36 kDa and minor proteins of 34 and 38 kDa. In HSV-1 the assembly proteins have been shown to be present in immature (B) capsids, but are removed prior to the formation of mature (C) capsids containing the viral DNA genome. Our work has shown that VZV produces capsids corresponding to the B and C forms. However, in contrast to HSV-1, VZV also produces "B/C" capsids that appear to contain both the assembly proteins and the viral DNA genome. Possible mechanisms for this are discussed. In addition, it was shown that VZV capsids appear to lack the 36 and 38 kDa proteins, and based on this observation we suggest that these may represent unprocessed forms of the assembly protein. In both HSV and CMV, a much larger, cross-reactive protein has been identified as the full-length product of the gene coding for the assembly protein. The homologous VZV gene (ORF 33) theoretically has the capacity to produce a 66 kDa protein. However, no such protein is readily apparent in VZV-infected cells. The presence of an immunoreactive 64 kDa protein was demonstrated in purified VZV capsids which may represent the full-length ORF 33 protein.

Simple fed-batch technique for high cell density cultivation of Escherichia coli

A simple fed-batch process for high cell density cultivation of Escherichia coli TG1 was developed. A pre-determined feeding strategy was chosen to maintain carbon-limited growth using a defined medium. Feeding was carried out to increase the cell mass concentration exponentially in the bioreactor controlling biomass accumulation at growth rates which do not cause the formation of acetic acid (mu < mu crit). Cell concentrations of 128 and 148 g per 1 dry cell weight (g l-1 DCW) were obtained using glucose or glycerol as carbon source, respectively.

Deficiency of the beta subunit of the eighth component of complement presenting as arthritis and exanthem

A 13-year-old boy presented with juvenile chronic arthritis of 6 months' duration. Antinuclear antibodies, anti-double-stranded DNA antibodies, and rheumatoid factor were not detected. Western blotting showed a deficiency of the beta subunit of the eighth component of complement. The same deficiency was present in the patient's sister. C8 beta deficiency is usually detected in individuals who survive meningococcal disease. There was no such history in this family. Juvenile chronic arthritis has not previously been described in patients with C8 beta deficiency.

Evaluation of pulse oximetry in horses surgically treated for colic

All 43 horses anaesthetised for colic surgery were premedicated with xylazine or diazepam. Anaesthesia was induced with guaifenesin and ketamine, horses were placed in dorsal recumbency and anaesthesia was maintained with isoflurane in oxygen and mechanical ventilation. Haemoglobin saturation readings (SpO2) were taken with a pulse oximeter and compared with computed haemoglobin saturation (SaO2) from arterial blood samples. Readings were taken over a range of SaO2 of 78-100%, mean arterial blood pressure ranged from 24 to 108 mmHg and PaO2 ranged from 53 to 490 mmHg. Analysis of 107 readings showed that SpO2 values predicted SaO2 but time, blood pressure and individual horse did not. Correlation coefficients between SpO2 and SaO2 were 0.85 for all values and 0.88 for values at 30 min. Values for bias and precision were calculated for all SpO2 values and for readings separated into 3 saturation groups: normal, low normal, and abnormal. The pulse oximeter tended to underestimate SaO2 at all times, and was less precise as the saturation decreased.

Effect of growth rate on stability and gene expression of recombinant plasmids during continuous and high cell density cultivation of Escherichia coli TG1

Continuous and fed-batch cultures of recombinant Escherichia coli TG1 were carried out in order to study plasmid stability and recombinant product formation at different specific growth rates. The aprotinin::beta-galactosidase gene (Ap::lacZ) was placed under the control of two different promoter/repressor systems, the PLac/lacI (pPLac8) and the lambda PL/cIts857 (pPL6) system. The chemically (0.5 mM IPTG) induced gene expression exhibited higher product activity and plasmid stability than the thermally (40 degrees C) induced expression. In fed-batch cultivations with the more stable E. coli TG1(pPLac8) a special feeding strategy allowed bacterial growth with a constant growth rate mu for several hours up to high cell densities. The cloned gene product activity was noticeably effected by the specific growth rate and the cell density at the moment of induction. In particular, the enzyme activities passed a pronounced maximum value in dependence of the set growth rate. The results indicate that fed-batch cultivation strategies are well suited to produce recombinant gene products.

Production of human parathyroid hormone by recombinant Escherichia coli TG1 on synthetic medium

Production of human parathyroid hormone (hPTH) by Escherichia coli TG1:I52cIts was studied. The hPTH is expressed as a fusion protein under control of the bacteriophage lambda pR promoter. The organism grows on glucose/mineral salt medium and the expression of the gene product was investigated under variation of temperature and growth rate prior to and after induction. hPTH formation largely depends on cultivation temperature and is optimal for a temperature shift from 30 to 38 degrees C. Product expression is growth coupled and specific hPTH concentration is independent of growth rate. The results are compared with a previous study on E. coli N4830:pEX-PPTH grown on complex media.

Diagnosing multiple sclerosis in childhood

By presenting the cases of 3 children with laboratory supported definite multiple sclerosis [LSDMS] according to Poser's diagnostic criteria, we illustrate the difficulties of diagnosing MS in childhood. In search for appropriate diagnostic criteria for childhood MS, the literature on childhood MS is reviewed, and the 3 cases presented are compared with the 15 hitherto reported with the diagnosis LSDMS. Specific difficulties of diagnosing MS in childhood are discussed. They include history taking in children, the multiple differential diagnostic possibilities, and the various clinical presentations. Due to these specific difficulties in childhood MS, we conclude that a strict use of Poser's criteria is indispensable, especially in childhood MS.

Repetitive injectable anesthesia in a 27-year-old horse

A 27-year-old horse was anesthetized 3 times a week for 4 weeks, to facilitate cobalt therapy of a squamous cell carcinoma in the left paranasal sinus. Limitations of facilities required transport of the anesthetized horse to and from the cobalt therapy room, therefore, injectable anesthesia was used. Initially, the horse was preanesthetized with xylazine (at 1.1 mg/kg IV) and butorphanol (0.04 mg/kg IV). After 3 anesthetic episodes, the xylazine dose was reduced to 0.4 mg/kg IV and the butorphanol was deleted from the regimen. Tiletamine-zolazepam (1.1 mg/kg IV) was used for induction and maintenance of anesthesia (although on 2 occasions a bolus of ketamine was used to maintain immobility). The length of the procedure varied from 10-45 minutes, and the recovery times to sternal and standing varied from 23-76 and 55-105 minutes respectively. Although numerous complications might be expected given the age of this horse and the physiologic and metabolic demands of repetitive injectable anesthetics, none were observed.

Studies on the production of human parathyroid hormone by recombinant Escherichia coli

Expression of human parathyroid hormone, hPTH(-1-84), by Escherichia coli N4830:pEX-PPTH was studied in controlled bioreactors. The hPTH is expressed as a fusion protein under control of the bacteriophage lambda PR promoter. In batch runs, low biomass concentrations but high specific hPTH productivities were obtained with complex TY (bactotryptone and yeast extract) medium whereas high biomass concentration and low specific productivities were found when fructose was used instead of bactotryptone (YF medium). The preinduction temperature was always 30 degrees C; the temperature shift to induce production of fusion protein was varied from 36 to 42 degrees C. Formation of hPTH passed a pronounced maximum as a function of induction temperature when using YF medium. However, the optimum temperature shift was 38 degrees C for both media used. For this temperature increase both media yielded about the same volumetric hPTH productivity (approx. 30 mg hPTH/1 per hour). By applying a fed-batch strategy for the YF medium, the productivity of the recombinant protein could be further increased more than fourfold. Compared to shake-flask experiments, the hPTH yield could be increased by a factor larger than 20.

Control of microbial activity by flow injection analysis during high cell density cultivation of Escherichia coli

The application of an automated flow injection analysis (FIA) system for on-line determination of microbial activity, during high cell density cultivations of Escherichia coli is reported. Based on a bioelectrochemical principle, the FIA method used a redox mediator (potassium hexacyanoferrate(III)) to facilitate electron transfer from the microorganisms to an electrochemical detector. Assays were carried out using a new sampling device which provided aseptic operation by use of a valve and chemical sterilisation. No sample dilution or pretreatment was necessary for biomass concentrations up to approx. 40 g l-1. The sample volume was 0.5 ml and the overall analysis time was 5 min. FIA signals were found to correlate well with the oxygen uptake rate (OUR). Changes in metabolic activity due to low substrate levels or high inhibitor concentrations in the cultivation medium became obvious from the FIA signals.

[Good results in reoperation of recurrent radicular syndrome following surgery for herniated nucleus pulposus]

In the period 1985-1986 twenty-four patients with a recurrent lumbar disk herniation were subjected to surgery in the department of Neurosurgery in the Academic Medical Hospital of Utrecht. In 25% of these patients the second lumbar disk herniation was at the same level and side as the first one. Recurrence of the disk rupture at the same side and level as the first one occurred most often within two years after initial surgery. A recurrent slipped disk at different lumbar level occurred after a time interval of two years or more. Correct diagnosis depends on the results of imaging techniques. All reoperated patients did well after surgery and could return to their work or normal daily obligations.

Psychiatric symptoms and mental changes as major features of multiple sclerosis

A patient is presented with clinically and laboratory supported definite multiple sclerosis who developed severe depression followed by mental deterioration. Magnetic resonance imaging MRI demonstrated multiple hemispherical lesions. It is suggested that the psychiatric and cognitive signs and symptoms observed in this patient are due to severe cerebral demyelination.

[Juvenile dermatomyositis, systemic lupus erythematosus and mixed connective tissue disease]

This paper covers the current insights into the classification, etiology, management and prognosis of juvenile dermatomyositis (JDMS) systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD). Since specific diagnostic tests for these autoimmune diseases are not available, diagnosis depends on the presence of defined criteria. Drug therapy in JDMS consists of prednisone at a low dosage (1 mg/kg/day). In SLE different therapeutic approaches are known depending on the occurrence of life threatening symptoms. The prognosis of MCTD is good, it is of prime importance to avoid overdosage of corticosteroids, since drug treatment is often not needed.

[Multiple sclerosis in childhood]

A 15-year-old girl presented with signs and symptoms indicative for multiple sclerosis. A final diagnosis could only be reached after 9 years follow up and with help of the MRI technique. The differential diagnosis of multiple sclerosis at a young age is discussed.

High cell density cultivation of Escherichia coli at controlled specific growth rate

A high cell density cultivation (HCDC) for growth of Escherichia coli in an especially designed glucose/mineral salt medium is proposed. The HCDC essentially starts as a batch process which is followed by a two-phase fed-batch cultivation. After unlimited growth at mu max = 0.45 h-1 in the batch part, growth was controlled at a reduced specific growth rate (mu = 0.11 h-1 less than mu max) over a period of 3 doubling times in which the biomass concentration increased from 12 to 95 g 1(-1) (phase 1 of fed-batch cultivation). Control of growth (mu) was realized by a PO2 control loop (by variation of glucose feeding) and a mu control loop (by variation of agitation speed N) while the actual mu was calculated from the off-gas composition. If the agitation rate cannot be increased anymore the mu controller is switched off (end of phase 1). In the following phase 2, mu declines, however, the still acting pO2 (glucose) controller guarantees sufficient O2 supply till the end of the cultivation with a biomass concentration of 110 g 1(-1) (dry mass). The proposed HCDC suppresses generation of inhibitory by-products and the high yield coefficients indicate the economy of the process.

Anesthetic management for instrumentation of the pregnant rhesus monkey

The anesthetic procedures used and the responses observed during maternal instrumentation on 38 pregnant rhesus monkeys (Macaca mulatta) during the second half of gestation are reported. A laparotomy with maternal instrumentation was performed in all animals. Anesthesia was induced with ketamine and maintained with halothane. Two animals delivered within five days of anesthesia and surgery and were unable to undergo experimentation. The remaining 36 animals underwent successful experimentation. Dysrhythmias, hypotension, and hypothermia were identified as complications of anesthesia.

Studies on the production of lipase from recombinant Staphylococcus carnosus

Production of lipase from recombinant Staphylococcus carnosus pLipPS1 was studied in standard stirred tank bioreactors. Only low lipase activity was obtained under conventional operating conditions, i.e., moderate to high stirring speeds and aeration rates for keeping the dissolved oxygen concentration at high levels. Additional targetted experiments indicated that the reason for the observed low lipase activity is lipase inactivation due to surface forces and shear stress at the gas/liquid interface. Therefore, a cultivation strategy is proposed that minimizes gas/liquid interfacial area and maximizes the driving concentration for O2 mass transfer by controlling the dissolved oxygen to low values by gentle stirring and low aeration rates. Thus, high lipase activities can be obtained even in larger scale standard stirred tank bioreactors.

Action of sympathomimetic drugs on the bronchial circulation of the horse

In the quietly standing horse I.V. administration of adrenaline decreased, and of dobutamine increased, bronchial artery flow. These changes paralleled changes in arterial pressure. With phenylephrine and noradrenaline bronchial artery flow decreased while arterial pressure increased, indicating active vasoconstriction in the bronchial circulation. With clenbuterol an increase in bronchial artery flow was accompanied by a decrease in systemic blood pressure, indicating bronchial arterial vasodilatation. We conclude that alpha-constrictor and beta 2-dilator receptors are present in the bronchial artery bed and that stimulation of these receptors could explain changes in flow seen in the horse during exercise and anaesthesia.

Treatment of low arterial oxygen tension in anesthetized horses with clenbuterol

Clenbuterol (0.8 microgram/kg intravenously) was administered to 10 anesthetized horses with an abnormally low PaO2 (less than 90 mm Hg) despite controlled ventilation with an oxygen-rich gas mixture. Results were compared with those from 10 controls to which no clenbuterol was given and in which conventional methods to increase PaO2 were ongoing. Horses treated with clenbuterol had higher PaO2 values for at least 90 minutes. Clenbuterol was associated with increased heart rate and profuse sweating. Clenbuterol can be administered intravenously to increase the PaO2 of mechanically ventilated horses that have low arterial oxygen tension while under inhalation anesthesia. Further studies are warranted to define more precisely the circumstances under which clenbuterol may be used safely.

Major histocompatibility complex class I and class II polymorphism in chronic idiopathic demyelinating polyradiculoneuropathy

Thirty-one chronic idiopathic demyelinating polyradiculoneuropathy (CIDP) patients have been typed for HLA-A, -B and -C antigens serologically and for HLA-DR, -DQ and -DP class II genes by RFLP analysis. Our results confirm a previously reported slight association with HLA-B8 and identify a stronger association with HLA-Cw7.

Memory and learning in outpatients with quiescent multiple sclerosis

In 22 (56%) of 39 quiet-stage multiple sclerosis (MS) patients with at least average intelligence quotients, performances in memory and learning tasks were normal, as compared with those of a control group (24 healthy volunteers). Of the remaining 44% (n = 17), 2 patients were amnesic and 5 had been judged to have suffered cognitive decline. Auditory word learning was particularly vulnerable; however, acquisition rate was not significantly different between MS patients and controls.

Performances of multiple sclerosis patients in tasks requiring language and visuoconstruction. Assessment of outpatients in quiescent disease stages

In a group of 39 multiple sclerosis (MS) patients with at least average intelligence quotients (IQ), performances were examined in tests requiring language usage and figure copying. Numbers of correct, digressive and erroneous responses were analysed and compared with those obtained in 24 healthy volunteers, matched to the patients group for socio-economic status. The examined specific tasks yielded no additional contribution to the prevalence estimation of cognitive deterioration (18%), as based on an assessment of general intelligence. Linguistic or cognitive-constructional problems were no more severe or more frequent in MS patients than those in control subjects. Upon writing or copying figures, pencil stroke and pencil pressure were deficient. Speed of reading aloud and of colour naming was decreased in the MS group, the most probable explanation being impaired control of the phonatory apparatus, oculomotor problems or weakness of colour vision. Decreases in speed of performance are not necessarily of cognitive origin. Differences between the present and previous reports based on similar tasks, appear to be connected partly with differences in patient selection. Of the present group, all MS patients were in quiescent disease stages, depression was mild or absent and physical handicap was less than in most studies reporting definite specific deficits.

Visuospatial problem solving, conceptual reasoning and sorting behaviour in multiple sclerosis out-patients

Visuospatial problem solving, conceptual reasoning and shifting of set were studied in out-patients with definite and probable MS. The sample of MS patients was homogeneous with respect to 2 important dimensions. All were out-patients, leading a normal although handicap-restricted social life. Furthermore, in all patients relapse or obvious instability of the disease were absent for at least a month. On Raven's Progressive Matrices, the Category test and the Wisconsin Modified Card Sorting test, no significant differences were found between the group of MS patients and a control group of healthy volunteers. However, 18% of MS patients and 4% of controls were rated as performing slightly below the expected levels of cognition. Stepwise regression analysis failed to reveal effects of illness variables, and no difference between patients with definite and probable MS could be detected. Clearly, most socially integrated MS patients in stable disease stages are capable of normal visuospatial problem solving, abstract reasoning and shifting of set.

Reaction time in ambulant multiple sclerosis patients. Part II. Influence of task complexity

Effects of task variables on reaction time (RT) were investigated in 39 multiple sclerosis (MS) patients and 25 matched control subjects, based on the premise that RT is sensitive to (subtle) changes of cognitive efficiency. The hypothesis to be tested held that inefficient cognitive processing in MS would be reflected in differences between RT patterns of MS and control subjects, and in inordinate RT increase in MS patients with increase of task complexity. No difference was found between MS patients and controls, or between MS subgroups, in (1) response to time uncertainty of stimulus presentations, (2) RT behaviour over stimulus presentations, and (3) RT change from simple to more complex conditions. No evidence of slowed cognitive processing was found in this sample of outpatients with relatively mild and stable MS. It is emphasised that executive and cognitive slowness have to be disentangled in research on MS and on so-called 'subcortical dementia', of which mental slowing is a key concept.

Reaction time in ambulant multiple sclerosis patients. Part I. Influence of prolonged cognitive effort

Reaction times (RT) were measured in 39 multiple sclerosis (MS) patients and 25 healthy controls, before and after comprehensive neuropsychological assessment lasting at least 4 h. The assessment required prolonged mental effort, which was assumed to induce fatigue. Simple and disjunctive RT were measured for visual and auditory stimuli. RT before and after prolonged effort were significantly longer in MS than in control subjects (with exception of auditory RT). This effect was related to disease duration and to simultaneous presence of brainstem, cerebellar and/or pyramidal signs. Age did not significantly contribute to the explanation of RT increase. In female patients, increasing distribution of functional lesions in the central nervous system was related with greater RT increase than in male patients. RT of MS and controls changed after prolonged mental effort and effort-related fatigue was experienced subjectively. Yet no differences in direction or degree of change in RT were found between controls and ambulant patients with stable MS who apparently had resources to overcome fatigue.

Guillain-Barré syndrome after varicella-zoster infection. Report of two cases

Two patients developed Guillain-Barré syndrome after varicella-zoster infection; a 4-year-old boy after chickenpox and a 74-year-old man after shingles. Both had decreased CD8-positive lymphocytes in the blood during the course of their illness. These cases and others reported in the literature suggest that varicella-zoster infection is a significant but rare trigger factor of Guillain-Barré syndrome. An alteration in the balance of helper and suppressor lymphocytes may be an important pathogenetic mechanism.

Visual function and pattern visual evoked response in optic neuritis

The disparity between clinical visual function and pattern visual evoked response (VER) was studied in 53 patients who had suffered an attack of optic neuritis (ON) more than six months before. The visual functions tested included Snellen visual acuity, colour vision, visual field, and contrast sensitivity. The effect of pattern presentation, check size, and luminance was tested by recording VERs with several stimulus configurations. VER amplitudes were found to be associated with the outcome of all four clinical tests, independently of check size, luminance, or the presentation method used. On the other hand VER latencies were hardly ever related to the results of any of the four clinical visual tests. These findings support the idea that VER amplitude provides information about visual spatial perception, while VER latency is more related to the extent of demyelination.

Residual lesions and early recurrent stenosis after carotid endarterectomy. A serial follow-up study with duplex scanning and intravenous digital subtraction angiography

In 109 internal carotid endarterectomies a complete serial follow-up study with ultrasonic duplex scanning was performed at 3, 6, and 12 months after operation. A duplex scan was also performed 2 years postoperatively in 75 cases. Moreover, the state of the endarterectomized carotid bifurcations was documented by intravenous digital subtraction angiography during hospitalization and at 12 months. At 3, 6, 12, and 24 months after operation the rate of significant recurrent stenosis was 6%, 12%, 6%, and 8%, respectively. Approximately half of the arteries with a significant stenosis at 1 year already demonstrated this lesion with intravenous digital subtraction angiography performed 1 week after operation. Persistent significant recurrent stenosis in the remaining arteries was probably the result of excessive myointimal proliferation. This occurred with a higher frequency in women (14.8%) than in men (4.1%). The greater number of the arteries with minimally or mildly disturbed spectral waveforms 3 months after endarterectomy spontaneously normalized or remained stable during the follow-up period. On the other hand, 40% of the arteries with a significant stenosis (diameter reduction of 50% or more) at the three-month control follow-up period increased to a more severe degree of stenosis during the first postoperative year. Most of the operated arteries did not significantly change during the second year.