The Short Warwick-Edinburgh Mental Well-being Scale (SWEMWBS) - A psychometric evaluation of adolescents in Sweden during the COVID-19 pandemic

The Short Warwick-Edinburgh Mental Well-being Scale (SWEMWBS) is effective in assessing positive aspects of mental health. Despite its advantages, little is known about group differences in the interpretation of SWEMWBS items across age groups, especially during the adolescence period. Hence, this study examined the psychometric properties of the SWEMWBS through Confirmatory Factor Analysis (CFA), Rasch analysis and network analysis of Swedish adolescents during the COVID-19 pandemic. A total of 5548 participants from the south of Sweden (i.e., Jönköping County) took part in this cross-sectional study through an online platform between September 2020 and October 2020. The CFA, Rasch (including differential item functioning, DIF) analysis and network analysis were used to examine the psychometric properties and measurement invariance of the SWEMWBS. The SWEMWBS had a unidimensional structure with robust psychometric properties. The CFA demonstrated measurement invariance across gender, school year and country of birth, which was also confirmed by Rasch DIF. Furthermore, considerable associations between the items of the SWEMWBS, general health and COVID-19 impact items were observed in network analysis. The SWEMWBS showed robust psychometric properties capable of assessing positive aspects of mental health and well-being among adolescents.

The myth of the total institution: Written narratives of patients' views of sanatorium care 1908-1959

Drawing on written narratives by 72 former sanatorium patients, this article explores, from patients' perspectives, the nature of the relationships between patients and staff in a Swedish sanatorium during the first half of the twentieth century. These narratives are discussed in the context of the total institution. This article suggests that this phenomenon was marked by inconsistencies that can be understood in terms of its situational and contradictory characteristics. Simultaneously, these narratives are in opposition to the assumption of the static and powerless patient adapted only to suit the logic of the institution.

Integrated production of polyhydroxyalkanoates (PHAs) with municipal wastewater and sludge treatment at pilot scale

A pilot-scale process was operated over 22 months at the Brussels North Wastewater Treatment Plant (WWTP) in order to evaluate polyhydroxyalkanoate (PHA) production integration with services of municipal wastewater and sludge management. Activated sludge was produced with PHA accumulation potential (PAP) by applying feast-famine selection while treating the readily biodegradable COD from influent wastewater (average removals of 70% COD, 60% CODsol, 24% nitrogen, and 46% phosphorus). The biomass PAP was evaluated to be in excess of 0.4gPHA/gVSS. Batch fermentation of full-scale WWTP sludge at selected temperatures (35, 42 and 55 °C) produced centrate (6-9.4 gCODVFA/L) of consistent VFA composition, with optimal fermentation performance at 42 °C. Centrate was used to accumulate PHA up to 0.39 gPHA/gVSS. The centrate nutrients are a challenge to the accumulation process but producing a biomass with 0.5 gPHA/gVSS is considered to be realistically achievable within the typically available carbon flows at municipal waste management facilities.

Polyhydroxyalkanoate (PHA) production from sludge and municipal wastewater treatment

Polyhydroxyalkanoates (PHAs) are biodegradable polyesters with comparable properties to some petroleum-based polyolefins. PHA production can be achieved in open, mixed microbial cultures and thereby coupled to wastewater and solid residual treatment. In this context, waste organic matter is utilised as a carbon source in activated sludge biological treatment for biopolymer synthesis. Within the EU project Routes, the feasibility of PHA production has been evaluated in processes for sludge treatment and volatile fatty acid (VFA) production and municipal wastewater treatment. This PHA production process is being investigated in four units: (i) wastewater treatment with enrichment and production of a functional biomass sustaining PHA storage capacity, (ii) acidogenic fermentation of sludge for VFA production, (iii) PHA accumulation from VFA-rich streams, and (iv) PHA recovery and characterisation. Laboratory- and pilot-scale studies demonstrated the feasibility of municipal wastewater and solid waste treatment alongside production of PHA-rich biomass. The PHA storage capacity of biomass selected under feast-famine with municipal wastewater has been increased up to 34% (g PHA g VSS(-1)) in batch accumulations with acetate during 20 h. VFAs obtained from waste activated sludge fermentation were found to be a suitable feedstock for PHA production.

Validation of EUCAST zone diameter breakpoints against reference broth microdilution

The European Committee on Antimicrobial Susceptibility Testing (EUCAST) began harmonizing clinical breakpoints in Europe 2002. In 2009, work to develop a disc diffusion method began and the first disc diffusion breakpoints calibrated to EUCAST clinical MIC breakpoints were published in December 2009. In this study we validated EUCAST clinical zone diameter breakpoints against the International Standard Organization (ISO) reference broth microdilution. A collection of 544 isolates (238 Gram-negative and 306 Gram-positive) were tested against a panel of antimicrobial agents. Antimicrobial susceptibility testing was performed with broth microdilution as described by ISO and disc diffusion in accordance with EUCAST methodology. Inhibition zone diameters and MIC values were interpreted and categorized (S, I and R) according to EUCAST clinical breakpoint table version 2.0. Categorical agreement (CA) as well as minor (mD), major (MD) and very major (VMD) discrepancies were determined. There was in general good correlation between susceptibility test results obtained with disc diffusion and broth microdilution. Overall CA was 97.3% for all combinations of organisms and antimicrobial agents (n = 5231) and the overall discrepancy rates were 110 (2.1%) mD, 24 (0.5%) MD and 7 (0.1%) VMD. The overall CA for Gram-positive and Gram-negative organisms were 98.7% (2346 tests) and 96.2% (2942 tests), respectively. Seven VMD were observed, five for Gram-positive organisms (coagulase negative staphylococci (n = 2) and Staphylococcus aureus (n = 3)) and two for Gram-negative organisms (Pseudomonas aeruginosa). Minor discrepancies were mainly observed in Gram-negatives and were related to different antimicrobial agents and species.

Identification and determination of chlorinated paraffins using multivariate evaluation of gas chromatographic data

Chlorinated paraffins (CPs) were found in the biodegradable fraction of source separated waste from Uppsala, Sweden. We identified and quantified the CPs by multivariate evaluation of gas chromatography-electron capture detection chromatograms. Using principal component analyses (PCA) we identified different types of CP-formulations and also obtain quantitative data. PCA yielded better identifications of individual CP-formulations than visual comparison of chromatograms. Partial least squares regression gave good calibration curves of the standards, but did not work for the waste samples. No source of CPs could be identified in the waste collection chain, and as the waste samples seemed to contain at least two different CP-formulations the source was probably to be found in the waste material itself. The method was used to determine CPs in additional environmental samples, demonstrating that multivariate methods may be developed into a powerful tool for identification and quantification of complex mixture.

Mixed culture polyhydroxyalkanoates production from sugar molasses: the use of a 2-stage CSTR system for culture selection

Polyhydroxyalkanoates (PHAs) are promising biodegradable polymers. The use of mixed microbial cultures (MMC) and low cost feedstocks have a positive impact on the cost-effectiveness of the process. It has typically been carried out in Sequencing Batch Reactors (SBR). In this study, a 2-stage CSTR system (under Feast and Famine conditions) was used to effectively select for PHA-storing organisms using fermented molasses as feedstock. The effect of influent substrate concentration (60-120 Cmmol VFA/L) and HRT ratio between the reactors (0.2-0.5h/h) on the system's selection efficiency was assessed. It was shown that Feast reactor residual substrate concentration impacted on the selective pressure for PHA storage (due to substrate-dependent kinetic limitation). Moreover, a residual substrate concentration coming from the Feast to the Famine reactor did not jeopardize the physiological adaptation required for enhanced PHA storage. The culture reached a maximum PHA content of 61%. This success opens new perspectives to the use of wastewater treatment infrastructure for PHA production, thus valorizing either excess sludge or wastewaters.

Antimicrobial susceptibility in Escherichia coli of human and avian origin--a comparison of wild-type distributions

In the present study, the antimicrobial susceptibilities of 97 Escherichia coli isolates from birds, and 100 clinical isolates from blood cultures, were determined by disk diffusion. The wild-type distributions were defined by the normalized resistance interpretation method. It is shown that the avian and clinical inhibition zone diameter distributions of wild-type E. coli are indistinguishable.

CMOS considerations in nanoelectromechanical carbon nanotube-based switches

In this paper, we focus on critical issues directly related to the viability of carbon nanotube-based nanoelectromechanical switches, to perform their intended functionality as logic and memory elements, through assessment of typical performance parameters with reference to complementary metal-oxide-semiconductor devices. A detailed analysis of performance metrics regarding threshold voltage control, static and dynamic power dissipation, speed, and integration density is presented. Apart from packaging and reliability issues, these switches seem to be competitive in low power, particularly low-standby power, logic and memory applications.

Near infrared reflectance spectroscopy as a tool to predict pesticide sorption in soil

We used near infrared reflectance spectroscopy (NIR) combined with chemometric methods to predict the sorption of lindane and linuron to 27 agricultural soils from Sweden. The NIR predictions were calibrated by principal component analysis (PCA) of the NIR spectra and sorption data obtained using the batch equilibrium technique. Partial least square regression PLSR of the NIR data could predict 85% of the soil sorption (K (d)) for lindane and 84% for linuron, respectively. The results indicate that NIR can be used as a rapid and simple method to predict pesticide sorption to and leaching from soils.

Solid-phase extraction and cleanup of organophosphorus pesticide residues in bovine muscle with gas chromatographic detection

The purpose of this investigation is to develop a rapid and simple method for the assessment of organophosphorus pesticides in bovine muscle by using solid-phase extraction (SPE). After extraction with ethyl acetate (EtOAc) the homogenate is centrifuged and filtered through sodium sulfate. The fat is precipitated in methanol by cooling and the extract is diluted with water and passed through a SPE column (Isolute ENV+). After elution with EtOAc, evaporation, and redissolution, the sample is injected into a gas chromatographic (GC) capillary column DB-1701 and detected by a flame photometric detector. Recoveries from bovine muscle fortified with 12 pesticides between 4 and 65 microg/kg include three levels ranging between 59% and 109% for ten of them. The two most polar pesticides (metamidophos and acephate) are not successful. The relative standard deviations are between 1% and 10% for the ten pesticides. A simplex method is used to optimize the GC conditions.

Brain activation during odor perception in males and females

Several studies indicate that women outperform men in olfactory identification tasks. The psychophysical data are more divergent when it comes to gender differences at levels of odor processing which are cognitively less demanding. We therefore compared cerebral activation with H2(15)O PET in 12 females and 11 males during birhinal passive smelling of odors and odorless air. The odorous compounds (odorants) were pure olfactory, or mixed olfactory and weakly trigeminal. Using odorless air as the baseline condition, activations were found bilaterally in the amygdala, piriform and insular cortices in both sexes, irrespective of the odor. No gender difference was detected in the pattern of cerebral activation (random effect analysis SPM99, corrected p < 0.05) or in the subjective perception of odors. Males and females seem to use similar cerebral circuits during the passive perception of odors. The reported female superiority in assessing olfactory information including odor identification is probably an effect of a difference at a cognitive, rather than perceptive level of olfactory processing.

Recent high incidence of fulminant hepatitis in Samara, Russia: molecular analysis of prevailing hepatitis B and D virus strains

Until 1991, the Russian city of Samara was largely isolated from other parts of Russia and the rest of the world. Very recently, Samara has seen an alarming increase in the incidence of hepatitis. The proportion of fulminant cases is unusually high. We wanted to assess the roles of hepatitis B virus (HBV) and hepatitis D virus (HDV) in acute viral hepatitis in this region by analyzing the prevailing strains of both and by determining their genotypes and possible origin. Serum samples were screened for different serological markers and by PCR followed by direct sequencing. Of the 94 HBV-positive samples (80% of which were acute infections), 37 (39%) were also HDV positive. Sixty-seven percent of the patients had anti-HCV antibodies. Twenty-five percent of all patients in the study had fulminant hepatitis. Statistically significant sex differences were found among fulminant cases. For HBV, the core promoter sequences of 62 strains were determined and all but one were found to be of genotype D. None of these had any deletions. Only one strain, from a patient with fulminant fatal hepatitis, showed multiple mutations. The pre-S2 region sequences of 31 HBV strains were also compared. Phylogenetically, these fell into two distinct groups within genotype D, suggesting different origins. For HDV, part of the region encoding the delta-antigen was sequenced from four strains. All proved to be of genotype I and were similar to Far Eastern and Eastern European strains. The contribution of intravenous drug use to the sharp increase in viral hepatitis in this unique setting is discussed.

Pharmacodynamic effects of sub-MICs of benzylpenicillin against Streptococcus pyogenes in a newly developed in vitro kinetic model

The pharmacodynamic effects of benzylpenicillin against Streptococcus pyogenes were studied in a new in vitro kinetic model in which bacterial outflow was prevented by a filter membrane. Following the administration of an initial dose of antibiotic, decreasing concentrations were produced by dilution of the medium. A magnetic stirrer was placed above the filter to avoid blockage of the membrane and to ensure homogeneous mixing of the culture. Repeated samplings were easily provided through a silicon diaphragm. Streptococci were exposed to a single dose corresponding to 1.5, 10, 100, or 500 x the MIC of benzylpenicillin and also to an initial concentration of 10 x the MIC of benzylpenicillin, followed by exposure to a repeated dose after 8 h yielding 10 or 1.5 x the MIC. Experiments were also performed with 10 x the MIC of benzylpenicillin with a half-life of 3 h or an initial half-life of 1.1 h that was altered to 3 h at the time point at which the antibiotic concentrations and MIC intersected. Bacterial killing and regrowth were followed by determining viable counts. The post-MIC effect (PME) was defined as the difference in time for the numbers of CFU in the culture vessel to increase 1 log10 CFU/ml, calculated from the numbers obtained at the time when the antibiotic concentration had declined to the MIC, and the corresponding time for a control culture, grown in a glass tube without antibiotic, to increase 1 log10 CFU/ml. To determine how much of the PME was attributable to subinhibitory concentrations, penicillinase was added to a part of the culture drawn from the flask at the time when the antibiotic concentration had fallen to the MIC. The longest PME was found in the experiments in which the half-life was extended from 1.1 to 3 h at the MIC. This illustrated that sub-MICs are sufficient to prevent regrowth. However, when the half-life was 3 h during the whole experiment, the PME was shorter, indicating that when concentrations decline slowly penicillin-binding proteins will already be present in amounts sufficient for regrowth at the time when the MIC is reached. The PME may prove to be a more reliable factor than the in vitro postantibiotic effect or postantibiotic sub-MIC effect for the design of optimal dosing schedules, since the PME, like the in vivo postantibiotic effect, includes the effects of subinhibitory concentrations and therefore better reflects the clinical situation with fluctuating antibiotic concentrations.

Prophylaxis with oral cefadroxil versus intravenous cefuroxime in trochanteric fracture surgery. A clinical multicentre study

A prospective, randomized study was performed in 559 patients to compare two doses of oral cefadroxil with three doses of intravenous cefuorxime as antibiotic prophylaxis in intra- and subtrochanteric hip fracture surgery. Antibiotic concentrations in the wound fluid were determined at the start and at the end of the operation. The first dose of cefadroxil was given about 2 h before surgery and cefuroxime about 30 min before operation. In 226/242 (93%) patients randomized to oral cefadroxil, the concentration in the wound during surgery was on average 15 micrograms/ml, i.e., well above the minimum inhibitory concentration (MIC-90) for Staphylococcus aureus. In the cefuroxime group, antibiotic levels in the wound exceeded the MIC-90 for S. aureus in 204/210 (97%) of the patients at the start and/or at the end of surgery. All patients were followed up for 4 months. One deep and five superficial infections occurred in the cefuroxime group and no deep but one superficial infection in the cefadroxil group (P = 0.07). S. aureus was cultured in three of the infected cases while cultures were negative in four patients. Four of the seven infected patients had adequate levels of antibiotic in the wound during surgery, and in three patients no antibiotic assay was performed. The infected patients did not differ in age, sex, operation time, bleeding or any other basic variable compared with patients who healed without complications. Two doses of cefadroxil seems to be practical and as effective as intravenously administered cefuroxime as antibiotic prophylaxis in trochanteric hip fracture surgery.

Clinical requirements for the security of the electronic patient record

The views of the clinician on security aspects of an electronic patient record are presented. The necessary qualifications are: it should be there, it should be true, it should be trustworthy.

Postantibiotic effect, and postantibiotic effect of subinhibitory concentrations, of sparfloxacin on gram-negative bacteria

The postantibiotic effect (PAE), the postantibiotic sub-MIC effect (PA SME), and the sub-MIC effect (SME) of a new oral quinolone, sparfloxacin, were determined for different strains of gram-negative bacteria. A PAE was induced by 10 x MIC of sparfloxacin for 2 h and the antibiotic was then eliminated by washing and dilution. The PA SME was studied by adding different sub-MICs during the postantibiotic phase, and the SME by exposing the controls to the sub-MICs alone. Growth curves were followed for 20 h by continuous monitoring of optical density in an automatic incubator. Sparfloxacin induced a PAE of 0.9-2.4 h for all strains except two clinical strains of Enterobacter cloacae. In accordance with earlier experiments with sparfloxacin and gram-positive bacteria, this study showed a PA SME that was nearly equal to the PAE plus the effect of the subinhibitory concentration alone (SME).

A new method to determine postantibiotic effect and effects of subinhibitory antibiotic concentrations

It has been shown that bacteria in a postantibiotic (PA) phase exposed to subinhibitory concentrations (sub-MICs) of antibiotics show a long delay before regrowth. This effect has been named the PA sub-MIC effect (PA SME). In the present study, we have used a new method to demonstrate this phenomenon. A computerized incubator for bacteria, Bioscreen C (Lab Systems, Helsinki, Finland), which incubates the bacteria, measures growth continuously by vertical photometry, processes the data, and provides a printout of the results was used. With this method, one may easily test several antibiotics against different bacteria for PA effects (PAEs), PA SMEs, and SMEs. In this study, the effects of benzylpenicillin against beta-hemolytic streptococci and pneumococci were examined. The bacteria were exposed to 2, 10, or 50x MIC for 2 h, washed and diluted, incubated in the Bioscreen C incubator, and then exposed to 0.1 to 0.9x MIC. The regrowth was monitored for 20 h. The PAE was calculated as the difference in the time required for the exposed and unexposed bacteria to grow to a defined point (A50) on the absorbance curve. A50 was defined as 50% of the maximum absorbance for the control cultures. The PA SMEs were calculated as the difference in the time required for the reexposed cultures and the unexposed controls to reach A50. The PAEs ranged between 0.6 and 3.2 h and varied little with the concentration used for the induction of the PAEs. At 0.2x MIC, the PA SMEs were 2 to 3 h longer than the PAEs. Higher sub-MICs increased this delay before regrowth. Most cultures exposed to sub-MICs alone were only slightly affected compared with the controls.

Isolated fracture of the lateral malleolus requires no treatment. 49 prospective cases of supination-eversion type II ankle fractures

54 patients with isolated SE II fractures through the lateral malleolus, with 2 mm maximum dislocation, were treated with an elastic bandage and immediate weight bearing. 2 patients suffered dislocation but both should not, on reassessment, have been included in the study. 49 of the remaining patients were assessed after an average of 1.5 years. All but 4 patients had very minor, if any, symptoms. The average sick leave was 6.3 weeks and the patients were back to normal activity in about 4 months. This virtual nontreatment was safe and beneficial to both the patients and the health service.

Oral cefadroxil prophylaxis in hip fracture surgery. Serum concentrations studied in 17 patients

Serum concentration-time curves were determined in seventeen 82 (60-90) year-old patients undergoing trochanteric hip fracture surgery after receiving 1 g of cefadroxil per os. All the patients attained a serum level of antibiotic high enough to inhibit the growth of Staphylococcus aureus and S. epidermidis. When orally administered, cefadroxil should be given within 2 hours before surgery.

Synthesis and binding properties of the fluorinated substituted benzamide [3H]NCQ 115, a new selective dopamine D2 receptor ligand

[3H]NCQ 115 [R)-5-bromo-2,3-dimethoxy-N-[1-([2,5-3H]-4- fluorobenzyl)-2-pyrrolidinyl)methyl)benzamide) was prepared by acylation of (R)-(2-aminomethyl)-1- ([2,5-3H]-4-fluorobenzyl)pyrrolidine, which was obtained in a stereo-conservative synthesis from (R)-prolinamide. Purification by reversed phase high performance liquid chromatography (HPLC) gave [3H]NCQ 115 with a radiochemical purity of greater than 99% and a specific activity of 0.97 GBq/mumol (36 Ci/mmol). Saturation analyses, association and dissociation kinetics as well as binding competition with several compounds of various classes were performed with [3H]NCQ 115 in rat striatal homogenates. Saturation analyses in vitro showed that [3H]NCQ 115 bound to a single binding site with a Kd = 214 pM and Bmax = 35.4 fmol/mg. The binding of [3H]NCQ 115 was dependent upon sodium ions, since the number of binding sites was altered when sodium ions were excluded from the incubation medium. NCQ 115 inhibited the binding of [3H]raclopride to dopamine D2 receptors with high affinity (Ki = 147 pM), having much lower affinity for other receptors. The affinity of this substituted 1-benzyl-2-pyrrolidinylmethyl benzamide was confined to the (R)-enantiomer, which contrasts with that of the corresponding N-ethyl derivatives such as FLB 457, raclopride, eticlopride, sulpiride and NCQ 298, where the pharmacological activity is found in the (S)-enantiomer. It can be concluded that [3H]NCQ 115 binds to dopamine D2 receptors in the rat striatum with high affinity and high selectivity. [3H]NCQ 115 can also be used for in vivo binding studies of the brain. [18F]NCQ 115 may be a suitable ligand for positron emission tomography (PET) studies of the human brain in vivo.

Potential antipsychotic agents 5. Synthesis and antidopaminergic properties of substituted 5,6-dimethoxysalicylamides and related compounds

A series of 3-substituted 5,6-dimethoxysalicylamides III (9-13 and 15) has been synthesized from the corresponding 2,5,6-trimethoxybenzoic acids. Relaxation times T1 and carbon chemical shifts of the methoxy groups in III showed that the 6-methoxy group adopts a nearly perpendicular orientation and the 5-methoxy group takes on a more coplanar orientation with respect to the ring plane in solution. The salicylamides III display a very high and stereoselective affinity for the [3H]spiperone and [3H]raclopride binding sites in vitro. Regioisomeric salicylamides IV also exhibit pronounced, but lower than III, affinity for the [3H]spiperone binding site. The structural requirements were further assessed by studies of the related amino analogues 23 and 24 and hydroxy analogue 27. The 3-bromo compound 11 (FLB 463) was studied in various in vivo models and compared with the dopamine-D2 antagonists sulpiride, raclopride, eticlopride, and haloperidol. The high potency of 11 to selectively block dopamine-D2 receptors in vitro and in vivo combined with indications on a low potential for motor side effects makes it a very interesting new member of the class of substituted salicylamides.

Susceptibility to beta-lactam antibiotics and gentamicin of gram-negative bacilli isolated from hospitalized patients: a Swedish multicenter study

A total of 952 blood and 1543 urine isolates of gram-negative bacilli from hospitalized patients in 1986-1987 were consecutively collected by 10 Swedish laboratories and tested for susceptibility to 8 beta-lactam antibiotics and to gentamicin. The isolates were mostly Escherichia coli (58% and 44%, respectively) and Klebsiella sp. (17% and 18%). Resistance to ampicillin in blood and urine isolates was found in 35% and 45%, respectively, to piperacillin in 5% and 6%, to cephalothin in 26% and 34%, to cefuroxime in 12% and 22%, to cefotaxime in 3% and 5%, to ceftazidime in 1% and 1%, to imipenem in 0.5% and 0.1%, to aztreonam in 3% and 2%, and to gentamicin in 0.8% and 0%. Resistance of clinically important gram-negative bacilli to new beta-lactam antibiotics and to gentamicin is infrequent in Sweden.

In vitro aminoglycoside resistance of gram-negative bacilli and staphylococci isolated from blood in Sweden 1980-1984

The in vitro susceptibility to gentamicin, tobramycin, amikacin and netilmicin in septicaemia isolates was followed during 1980-1984 in 6-8 Swedish laboratories. The bacterial distribution was similar over the years and was dominated by Escherichia coli and staphylococci. Resistance to gentamicin was found in 2.3-3.6%, to tobramycin in 1.4-3.4%, to amikacin and netilmicin in 0.5-0.9%. Production of aminoglycoside modifying enzymes was observed among resistant strains.

Flow injection analysis for the determination of urea in cow's milk

An inexpensive and easily automated flow injection method for determination of urea in cow’s milk was evaluated. Urea is hydrolysed by urease and in a gas diffusion cell the ammonia formed passes a membrane into an indicator solution. The resulting colour change of the indicator is measured at 590 nm.

The repeatability of the analysis, expressed as the coefficient of variation (C.V.), was between 0.5 and 1.2%. Measured (y) and expected (x) milk urea concentrations after addition of known amounts of urea were related according to the equation y = 1.00× – 0.12 with a C.V. for the regression of 1.8%. Recommended amounts (0.02 %) of the preservative bronopol (2-bromo-2-nitropropane-1,3-diol) added to the milk did not affect the results (P > 0.05).

Steady state pharmacokinetics of trimethoprim 300 mg once daily in healthy volunteers assessed by two independent methods

The steady state pharmacokinetics of trimethoprim was determined after 300 mg orally once daily to 6 healthy volunteers for 9 days. The microbiological assay of plasma level was unreliable at trimethoprim concentrations greater than 4 micrograms/ml, so results from an HPLC-assay are given. Steady state was present after 3 days. The plasma concentration peaked 1 to 4 h (mean 2.0 h) after the dose at a mean of 6.0 micrograms/ml (range 3.1-9.5 micrograms/ml); the minimum value was 1.5 micrograms/ml (range 0.6-2.9 micrograms/ml). The mean AUCss was 77 micrograms/ml X h and the mean plasma clearances was 67 and 74 ml/min on Days 8 and 9. Renal clearance was about 60% of the plasma clearance. The average plasma half life was 10.6 h (range 8.7-15.3 h). Thus, there was considerable interindividual variation in all pharmacokinetic parameters. 72 h after the last dose trimethoprim was detectable in plasma in only 1 of the 6 subjects. The minimum urinary concentration of trimethoprim during treatment was always well above (range 22 to 220 micrograms/ml) the MIC values for most urinary tract pathogens. Therefore, a daily dose of 300 mg trimethoprim results in a therapeutic concentration in urine at steady state that lasts throughout the dosing interval and in most subjects probably lasts also for a further 24 h. Trimethoprim administration raised mean serum creatinine from 67 to 97 mumol/l, probably due to competitive inhibition of the tubular secretion of creatinine.

Oral pivampicillin and amoxycillin in newborn infants

Ampicillin was administered intramuscularly and amoxycillin or pivampicillin orally to 14 fasting newborn infants, 6-13 days old, in a cross-over trial. The dose was 50 mg/kg twice daily. The mean peak plasma level of amoxycillin and pivampicillin was 58% (range 35-96%) and 48% (33-82%) of that noted after i.m. ampicillin, which gave a value of about 44 +/- 5 micrograms/ml (mean +/- SEM) in both groups. The area under the time-concentration curve was 75% (range 60-101%) of that of i.m. ampicillin for amoxycillin and 51% (20-76%) for pivampicillin (p less than 0.05). Both drugs, especially amoxycillin, should be useful for oral treatment of neonatal infections caused by susceptible microorganisms in infants who are not critically ill.

Effect of saliva stimulants (Hybrin and malic acid) on cervical root surfaces in vitro

Two saliva stimulating drugs, solutions of Hybrin and malic acid were in an in vitro study found to have a heavy demineralizing effect on the root surface of the dental hard tissue. Consequently the drugs cannot be recommended to patients suffering from dry mouth reaction.

Azidocillin levels in tracheobronchial secretions

Concentrations of azidocillin in serum and tracheobronchial secretions were followed in 20 patients after an oral dose of 0.75 g of the drug. Serum concentrations were followed for 4 h and the concentration in tracheobronchial secretion was determined in samples taken through a fibreoptic bronchoscope 1--2 h after administration. The concentration in secretions varied between hardly measurable levels and 1.1 micrograms/ml. No correlation between levels in serum and tracheobronchial secretion was found. A slight tendency to higher secretion levels was found when the bronchoscopy showed signs of tracheobronchitis.

A dose response study with bacampicillin in uncomplicated gonorrhoea

In a systematic study of dose-response relationship 883 patients with uncomplicated gonorrhoea were given single oral doses of 400, 800 or 1600 mg bacampicillin, with 1 g probenecid. A single dose of bacampicillin 800 mg plus probenecid was the minimum effective dose in patients with fully ampicillin-sensitive strains. In patients with gonococci showing reduced sensitivity to ampicillin, 1600 mg bacampicillin was required to reach a cure rate above 95%. Bacampicillin was well tolerated in all treatment groups. Side-effects were reported in 4.6% of the courses of treatment. The most frequent adverse reaction was loose stools (1.9%), which was noted more often after the 1600 mg dose but was considered to be of no or very little clinical importance.

Wound infections after surgery in a modern operating suite: clinical, bacteriological and epidemiological findings

A prospective study of 2983 operations in general and orthopaedic surgery during 3 years performed in four operating theatres in a modern operating suite was carried out in order to evaluate the importance of airborne infection. Weekly nose-and-throat samples were taken from the surgical staff and pre-operative samples were taken from the nose, throat, skin and perineum of the patients. The air contamination was followed by using settle plates, which showed low mean counts of total bacteria of between 9 and 15 c.f.u./m(2)/min, with mean counts of Staph. aureus of between 0.03 and 0.06 c.f.u./m(2)/min. No correlation was found between the total number of bacteria and the incidence of post-operative infections or between the amount of Staph. aureus in the air and post-operative Staph. aureus infections. It was concluded that further increases in ventilation could, at best, only marginally affect the incidence of post-operative infection.The post-operative wound-infection rate was 9.0%. In various types of surgery, the infection rates varied from 5.3% in clean operations to 47.6% in dirty surgery. About one third of the infections were classified as moderate or severe.Adverse patient factors, such as immunodeficiency, steroid treatment, intensive care, etc., increased the rate to 15.0%; in ;normal' patients it was 3.8%.Among the bacteria isolated, gram-negative bacilli (31% of wounds), often together with other bacteria, and Staph. aureus (28%) predominated, but in 25% no specimens were taken.Of 76 post-operative Staph. aureus infections, 32 were caused by the patients' own strains, and of the remaining 44 infections, 22, or 8% of all infections, could be traced to strains present in the air and/or the respiratory tracts of staff during the operation.The length of pre-operative hospital stay had no influence on the carrier rate of Staph. aureus in patients. The incidence of post-operative wound infection was significantly higher in patients carrying Staph. aureus and was even higher if these bacteria were found on the skin.Patients with wound infections stayed, on an average, 15 days longer than patients without infections. In serious infections the increase in duration of stay was > 20 days. Although infections were commoner in older patients, the average additional hospital stay of infected patients did not increase with age. If the post-operative infections studied in a concurrent retrospective study are taken into account more than 12 000 bed-days were due to post-surgical wound infections in the period studied or, in other words, some 12 beds (corresponding to 5.5% of the total) were always occupied by infected patients.