Insect detect: An open-source DIY camera trap for automated insect monitoring

Insect monitoring is essential to design effective conservation strategies, which are indispensable to mitigate worldwide declines and biodiversity loss. For this purpose, traditional monitoring methods are widely established and can provide data with a high taxonomic resolution. However, processing of captured insect samples is often time-consuming and expensive, which limits the number of potential replicates. Automated monitoring methods can facilitate data collection at a higher spatiotemporal resolution with a comparatively lower effort and cost. Here, we present the Insect Detect DIY (do-it-yourself) camera trap for non-invasive automated monitoring of flower-visiting insects, which is based on low-cost off-the-shelf hardware components combined with open-source software. Custom trained deep learning models detect and track insects landing on an artificial flower platform in real time on-device and subsequently classify the cropped detections on a local computer. Field deployment of the solar-powered camera trap confirmed its resistance to high temperatures and humidity, which enables autonomous deployment during a whole season. On-device detection and tracking can estimate insect activity/abundance after metadata post-processing. Our insect classification model achieved a high top-1 accuracy on the test dataset and generalized well on a real-world dataset with captured insect images. The camera trap design and open-source software are highly customizable and can be adapted to different use cases. With custom trained detection and classification models, as well as accessible software programming, many possible applications surpassing our proposed deployment method can be realized.

Prospects for online adaptive radiation therapy (ART) for head and neck cancer

BACKGROUND

The aim of the present study is to examine the impact of kV-CBCT-based online adaptive radiation therapy (ART) on dosimetric parameters in comparison to image-guided-radiotherapy (IGRT) in consecutive patients with tumors in the head and neck region from a prospective registry.

METHODS

The study comprises all consecutive patients with tumors in the head and neck area who were treated with kV-CBCT-based online ART or IGRT-modus at the linear-accelerator ETHOS™. As a measure of effectiveness, the equivalent-uniform-dose was calculated for the CTV (EUDCTV) and organs-at-risk (EUDOAR) and normalized to the prescribed dose. As an important determinant for the need of ART the interfractional shifts of anatomic landmarks related to the tongue were analyzed and compared to the intrafractional shifts. The latter determine the performance of the adapted dose distribution on the verification CBCT2 postadaptation.

RESULTS

Altogether 59 consecutive patients with tumors in the head-and-neck-area were treated from 01.12.2021 to 31.01.2023. Ten of all 59 patients (10/59; 16.9%) received at least one phase within a treatment course with ART. Of 46 fractions in the adaptive mode, irradiation was conducted in 65.2% of fractions with the adaptive-plan, the scheduled-plan in the remaining. The dispersion of the distributions of EUDCTV-values from the 46 dose fractions differed significantly between the scheduled and adaptive plans (Ansari-Bradley-Test, p = 0.0158). Thus, the 2.5th percentile of the EUDCTV-values by the adaptive plans amounted 97.1% (95% CI 96.6-99.5%) and by the scheduled plans 78.1% (95% CI 61.8-88.7%). While the EUDCTV for the accumulated dose distributions stayed above 95% at PTV-margins of ≥ 3 mm for all 8 analyzed treatment phases the scheduled plans did for margins ≥ 5 mm. The intrafractional anatomic shifts of all 8 measured anatomic landmarks were smaller than the interfractional with overall median values of 8.5 mm and 5.5 mm (p < 0.0001 for five and p < 0.05 for all parameters, pairwise comparisons, signed-rank-test). The EUDOAR-values for the larynx and the parotid gland were significantly lower for the adaptive compared with the scheduled plans (Wilcoxon-test, p < 0.001).

CONCLUSIONS

The mobile tongue and tongue base showed considerable interfractional variations. While PTV-margins of 5 mm were sufficient for IGRT, ART showed the potential of decreasing PTV-margins and spare dose to the organs-at-risk.

Do floral resources affect fitness of adult Cydia pomonella (Linnaeus 1758) (Lepidoptera: Tortricidae)?

The introduction of flowering plants into orchards can increase functional biodiversity in pome fruit cultivation. Plants provide nectar, pollen and prey resources supporting pollinators and natural enemies. However, pests may also benefit from floral diets and a careful selection of plants is necessary to reduce any risk of pest proliferation. The codling moth Cydia pomonella is a major pest in apple growing worldwide and adults are known to consume sugars. The impact of floral diets (parsnip, wild carrot, coriander, red clover) on longevity, fecundity and fertility of adult codling moth was examined under laboratory conditions. In general, male moths lived longer than females, regardless of dietary treatments. Moths survived longest when supplied with parsnip flowers as a floral diet. Contrary to carrot, coriander resulted in higher longevity of adult C. pomonella compared to moths provided with red clover as a negative control. Adult nutrition on floral diets did not affect fecundity substantially. As expected, the majority of eggs were laid within the first week. Prolongation of moths' lifespan by floral diets did not significantly increase the total number of eggs laid in contrast to a diet with 25% sucrose solution. According to these results, the risk of inadvertently promoting codling moth when growing selected flowering plants in the orchard will be rather low, because the fitness of the moths and especially the reproduction of the females will not be substantially enhanced.

Suitability of European Trichogramma Species as Biocontrol Agents against the Tomato Leaf Miner Tuta absoluta

The tomato leaf miner Tuta absoluta, originally from South America, is an invasive species threatening European tomato crops. Since various insecticides have become ineffective in controlling T. absoluta, effective and environmentally friendly alternatives are needed. Biological control, especially by Trichogramma parasitoids, is considered to be an effective means of reducing this pest. Thus, the aim of our study was to identify promising candidates of Trichogramma parasitoids for biological control of T. absoluta in Europe. We assessed the efficiency of nine European Trichogramma species and compared them to Trichogramma achaeae, as this species is already commercially available. Firstly, we verified species identity of the 10 rearing strains using molecular and morphological methods. Then, host acceptance, host preference (T. absoluta vs. rearing host Sitotroga cerealella eggs) and host searching capacity were tested under laboratory conditions. Our results indicated that T. nerudai, T. pintoi and T. cacoeciae achieved a similar level of parasitism on potted tomato plants as T. achaeae. For the next step, these promising strains should be tested under greenhouse conditions.

Managing Floral Resources in Apple Orchards for Pest Control: Ideas, Experiences and Future Directions

Functional biodiversity is of fundamental importance for pest control. Many natural enemies rely on floral resources to complete their life cycle. Farmers need to ensure the availability of suitable and sufficient floral biodiversity. This review summarizes 66 studies on the management of floral biodiversity in apple orchards, published since 1986. Approaches followed different degrees of intervention: short-term practices (mowing regime and weed maintenance, cover crops), establishment of durable ecological infrastructures (perennial flower strips, hedgerows) and re-design of the crop system (intercropping, agroforestry). Although short-term practices did not always target the nutrition of natural enemies by flowering plants, living conditions for them (alternative prey, provision of habitat) were often improved. Perennial flower strips reliably enhanced natural enemies and techniques for their introduction continuously developed. Resident natural enemies and their impact in pest control reacted positively to the introduction of a more diversified vegetation, whereas the response of very mobile organisms was often not directly linked to the measures taken. A careful selection and management of plants with particular traits exploitable by most natural enemies emerged as a key-point for success. Now the elaborated design of such measures needs to be adopted by stakeholders and policy makers to encourage farmers to implement these measures in their orchards.

Explorative Data Analysis of Drosophila suzukii Trap Catches from a Seven-Year Monitoring Program in Southwest Germany

Over the last decade, Drosophila suzukii Matsumura, an invasive pest of soft-skinned fruits, gradually established itself in Europe, often resulting in significant economic losses. In 2011, when D. suzukii was first described for Germany, the Julius Kühn Institut (JKI) started a monitoring program in southwest Germany to study the occurrence and activity of the fly. Capture data from late 2011–early 2018 from 100 traps were analyzed for the effect of weather and immediate habitat on trap captures at different times of the year. We identified five phases in the annual population development cycle of D. suzukii. We found that the mild winter of 2013/2014 helped the thorough establishment of D. suzukii in Germany. Habitat types in the immediate vicinity of the trap and local weather conditions had a strong influence on trap captures. Forest borders and hedges were found to provide adequate overwintering shelter for the flies. Trap captures in forests and hedges were generally higher than those of vineyards and orchards, even during the fruiting seasons. Summer capture rates were correlated with the number of heat days and precipitation. We also discuss briefly the limitations of using trap captures as representative of fly density in the field.

Mass Release of Trichogramma evanescens and T. cacoeciae Can Reduce Damage by the Apple Codling Moth Cydia pomonella in Organic Orchards under Pheromone Disruption

Cydia pomonella is a major pest in apples in Denmark. Trichogramma spp. are known biocontrol agents of C. pomonella eggs and two naturally occurring species in Denmark, which are also both commercially available, were chosen for mass-release trials. Trichogramma evanescens, T. cacoeciae or a mix of the two species were evaluated for mass-release to control C. pomonella in two commercial organic apple orchards, one in 2012 and one in 2013, using a complete randomized block design. Pheromone disruption was used in both orchards, making the study one of the first to evaluate Trichogramma release under a mating disruption regime. Trichogramma activity was assessed using bait cards with Sitotroga cerealella eggs. The percent C. pomonella damaged fruit was recorded and the fruit yield was estimated. In 2012 cool and wet weather conditions resulted in low Trichogramma activity (<16% bait cards parasitized) and only T. evanescens was recovered from bait cards. The conditions in 2013 were warmer but T. evanescens was still >10 times more frequently found in bait cards than T. cacoeciae. There was a significant effect of the treatment and year (p = 0.009) and of the sampling period (p = 0.0008) on Trichogramma activity (proportion bait cards parasitized), with no significant difference between treatments in 2012. In 2013 the highest activity was found in T. evanescens and mixed treatments, in July reaching 69% and 47% bait cards parasitized, respectively. Fruit damage was highest in the control plots (7.1%) compared with Trichogramma treatments (T. evanescens 2.8%, T. cacoeciae 3.8%, mixed 3.3%) (p = 0.028). Yield did not differ significantly between treatments. In conclusion, Trichogramma mass release is a promising biocontrol method for use in the Danish climate, but further studies are needed regarding the performance of the two Trichogramma species (and potential other Trichogramma species) towards C. pomonella eggs in the field to identify the best biocontrol candidate.

[Children and Adolescents with Asthma Differ in Lung Function Parameters and Exhaled NO from Children and Adolescents with Obesity]

BACKGROUND

The prevalence of asthma and overweight/obesity in children and adolescents is continuously increasing over the last decades. It remains unclear if overweight/obesity raises the risk of developing asthma or if an uncontrolled asthma increases the risk of developing overweight/obesity by restricting physical activity.

OBJECTIVES

We aimed to elucidate, if children and adolescents with overweight/obesity differ from normal-weight asthmatics in lung functions parameters (FEV1, FEV1/VC, MEF50 and SRtot) and in exhaled nitric oxide (FeNO).

METHODS

Totally, n=142 children and adolescents aged 6-18 years were included in this study: group 1 comprised n=44 with overweight/obesity defined as a Body-Mass-Index (BMI)>90th percentile; group 2 n=44 with a doctors diagnosed bronchial asthma according to the GINA-guidelines, and group 3 with n=36 pulmonary healthy controls. N=18 children with both asthma and overweight/obesity were excluded from further analysis. We collected data about socio-demographic variables from a standardized questionnaire, bodyplethysmography (FEV1, FEV1/VC, MEF50 and SRtot) and FeNO.

RESULTS

Normal-weight children and adolescents with asthma had significantly lower FEV1/VC (Tiffenau-Index 90,9±12,8) and MEF50 (84.0% predicted±27.6) than children with overweight/obesity (97,6±12,4 p=0.001 respectively 99.1±20.9 p=0.001) and healthy controls (98±13,5 p=0,003; 96.7±19.3 p=0.011). Normal weight asthmatics had a significantly higher FeNO (38.3 ppb) than children and adolescents with overweight/obesity (14.0 ppb p=0.014).

CONCLUSIONS

Normal-weight children and adolescents with asthma differ significantly both in their lung function parameters as well as in their exhaled nitric oxide concentration from children and adolescents with overweight/obesity. For clinical practice it is important to note that children and adolescents with overweight/obesity have no signs of an obstructive airway diseases and are as resilient as healthy children and adolescents with regard to their lung function. The possible late-onset of asthma symptoms and lung function changes in children and adolescents with overweight/obesity requires further detailed longitudinal studies.

The Sex Pheromones of Two Pine Sawfly Species, Gilpinia frutetorum and Gilpinia socia: Chemical Identification, Synthesis and Biological Activity

3,7-Dimethylpentadecan-2-ol and 3-methylpentadecan-2-ol were identified in female whole body extracts from the two pine sawfly species Gilpinia frutetorum and Gilpinia socia. This is the first observation of 3-methylpentadecan-2-ol in extracts of a female pine sawfly species. Synthetic and highly pure stereoisomers of 3,7-dimethylpentadecan-2-ol and 3-methylpentadecan-2-ol were used to verify that the (2S,3R,7R)-isomer of 3,7-dimethylpentadecan- 2-ol and (2S,3R)-3-methylpentadecan-2-ol were present in the extracts. The four stereoisomers of 3-methylpentadecan-2-ol and their biologically active esters were produced via chemoenzymatic methods and the synthesis is described in detail. Male G. socia antennae responded strongly in EAG recordings to the (2S,3R)-isomer of the acetate and propionate of 3-methylpentadecan-2-ol. Male antennae of both G. frutetorum and G. socia also responded to the (2S,3R,7R)- and (2S,3R,7S)-acetates of 3,7-dimethylpentadecan-2-ol

Sex pheromone of the pine sawfly, Gilpinia pallida: chemical identification, synthesis, and biological activity

We present the identification of the sex pheromone in the pine sawfly, Gilpinia pallida, including analysis of the female pheromone content, male antennal response and attraction in the field, and synthesis of the most active pheromone component. Several 3,7-dimethyl-2-alkanols were identified from female whole-body extracts, including some compounds with a 2R configuration. This is the first observation of such compounds in a pine sawfly species. Antennae of male G. pallida responded strongly in electroantennograph (EAG) recordings to the (2S,3R,7R)-isomers of the propionates of 3,7-dimethyl-2-tridecanol, 3,7-dimethyl-2-tetradecanol, and 3,7-dimethyl-2-pentadecanol, as well as to the acetates of the tri- and pentadecanols (the acetate of the tetradecanol was not tested). The propionate of (2S,3R,7R)-3,7-dimethyl-2-tetradecanol caught more males in the field than the corresponding isomer of tri- or pentadecanol. We suggest that the (2S,3R,7R)-isomer of 3,7-dimethyl-2-tetradecanol is likely the main sex pheromone precursor in G. pallida, with a subsidiary role for the (2S,3R,7R)-isomer of the tridecanol. Preparation of highly pure (2R,3R,7R)- and (2S,3R,7R)-stereoisomers of 3,7-dimethyl-2-tetradecanol, including the biological active esters, was performed via chemoenzymatic methods and is described in detail.

Renal Complications Associated with Human Parvovirus B19 Infection in Early Childhood

A previously healthy two-year-old girl presented with proteinuria and macroscopic haematuria. Laboratory findings included haemolytic anaemia with thrombocytopenia. Interestingly, continuing reticulocytopenia was noted. Therefore an acute parvovirus B19 infection was suspected, which could be confirmed by serological and molecularbiological evidence. This case report underlines renal complications of parvovirus B19 infection in early childhood including haemolytic-uraemic syndrome (HUS)-like episodes, and potential pathogenetic mechanisms are discussed.

Comparative pathogenesis of the Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus in noctuid hosts of different susceptibility

Neonate larvae of the noctuid moth Spodoptera exigua were susceptible to an infection by Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus (HaSNPV). Biological activity (LD(50),ST(50)) of the virus was considerably reduced as compared to its activity in the homologous host, H. armigera. Pathogenesis was studied using a recombinant HaSNPV carrying a green fluorescent protein gene, which induces fluorescence in infected cells to mark infection. In larvae of H. armigera, fluorescence was pronounced in the fat body after 2.9 days post infection and could also be detected in several other tissues. In contrast, fluorescence was not observed in tissues of S. exigua until 9 days post infection and was restricted almost exclusively to cells of the ganglia. Examination of serial sections of wildtype HaSNPV-infected S. exigua-larvae revealed a similar pattern of tissue tropism. Apparently, HaSNPV does not undergo the usual steps in host invasion and infection in this insect species, but targets specifically to nervous tissue.

Fentanyl and morphine discrimination in rats continuously infused with fentanyl

Rats were trained to detect the stimulus properties of fentanyl, 0.04mg/kg. Tested acutely, fentanyl generalized to, and morphine substituted for, the fentanyl training stimulus, although morphine was approximately 100-fold less potent than fentanyl in producing this stimulus. Subsequently, these rats were implanted with pumps (0.25ml volume) that delivered osmotically 1µl/h of solution containing either 3µg/µl (n = 16) or 6µg µl (n = 16) of fentanyl. When tested shortly after pump implantation, saline administration resulted in fentanyl-lever selection, indicating that the pumps were releasing fentanyl. Fentanyl-lever selection peaked at approximately 8 h after implantation; by 24 to 72 h after implantation, saline injection produced mainly saline-lever selection. On days 4 and 5 of chronic infusion of fentanyl, the fentanyl and morphine dose-effect curves were redetermined in both groups: both curves had shifted upwards, and the degree of shift occurred as a function of the dose of fentanyl infused continuously. After 6 days of infusion, the pumps were removed, and the detection of the fentanyl training stimulus was tested at 4, 12 and 24h after pump removal. At 12 h after removal, the percentage of subjects selecting the fentanyl lever following 0.04 mg/kg of fentanyl decreased to 53%, and this recovered to 87% by 24 h following pump removal. These results demonstrate tolerance to the stimulus properties of opioids with a few hours from the time of insertion of the pumps; the tolerance was not complete as shown by the results obtained during dose-effect testing with the pumps in place; finally tolerance was observed for a brief period when the pumps infusing fentanyl were removed (withdrawal tolerance). No evidence was obtained for asymmetric tolerance between fentanyl and morphine.

Opioid reward mechanisms: a key role in drug abuse?

There is increasing evidence to implicate the mesolimbic dopamine system in the rewarding effects of drugs of abuse such as opioids, psychostimulants, and alcohol, and in addition endogenous opioids may play a key role in the underlying adaptive mechanisms. Opioid agonists with affinity for mu and delta opioid receptors are rewarding, whereas opioid agonists with affinity for kappa receptors are aversive. These opposing motivational effects are paralleled by an increase and decrease, respectively, of dopamine release in the nucleus accumbens. Opposite effects are induced in response to selective antagonists for these different receptor types, pointing to tonically active endogenous opioid reward mechanisms. Withdrawal from chronic morphine results in sensitization for opioid reward; an effect that is counteracted by kappa opioid agonists. The rewarding effects of psychostimulants such as cocaine and amphetamine, mediated by the mesolimbic dopamine pathway, are modulated by opioid mechanisms in both directions: sensitization by morphine pretreatment, inhibition by kappa receptor agonists. A modulatory role of endogenous opioids is also suggested from biochemical data, showing increased dynorphin and kappa receptor expression after chronic cocaine treatment. Alcohol reward involves the mesolimbic reward system also, and opioids modulate this behaviour. Naltrexone as well as selective mu and delta opioid receptor antagonists decrease alcohol consumption in operant conditioning models. Biochemical approaches point to a functional deficit of endogenous opioids in genetic models exhibiting high prevalence for alcohol intake. The therapeutic implications of these data are discussed.

Endogenous opioid systems and alcohol addiction

Alcohol exerts numerous pharmacological effects through its interaction with various neurotransmitters and neuromodulators. Among the latter, the endogenous opioids play a key role in the rewarding (addictive) properties of ethanol. Three types of opioid receptors (mu, delta and kappa) represent the respective targets of the major opioid peptides (beta-endorphin, enkephalins and dynorphins, respectively). The rewarding (reinforcing) properties of mu- and delta-receptor ligands are brought by activation of the mesolimbic dopamine system which ascends from the ventral tegmentum of the midbrain (VTA) to rostral structures; of these, the nucleus accumbens (NAC) is of particular importance in drug addiction. In contrast, dysphoria results from activation of kappa-receptors. The neurochemical manifestations of these opposing effects are, respectively, increases and decreases in dopamine release in the NAC. Several lines of evidence indicate that alcohol interferes with endogenous opioid mechanisms which are closely linked with dopamine transmission in the mesolimbic pathway. The view that condensation products of dopamine and alcohol-derived aldehyde (tetrahydroisoquinolines) play a role remains controversial. There is, however, much information on the direct (acute and chronic) effects of alcohol on the binding properties of opioid receptors, as well as modulation of opioid peptide synthesis and secretion (e.g. a suggested increase in beta-endorphin release). In view of the reinforcing properties of alcohol, it is relevant to consider behavioural studies involving alcohol self-administration in rodents and primates. Low doses of morphine have been found to increase, and higher doses of the opiate to decrease, alcohol consumption. Conversely, opioid antagonists such as naloxone and naltrexone (which bind to non-selectively opioid receptors) have been shown to decrease alcohol consumption under various experimental conditions. Similar results have been reported when selective mu- or delta-receptor antagonists are administered. Results obtained in genetic models of high preference for alcohol also support the view that alcohol intake depends on the activity of the endogenous opioid reward system and that alcohol consumption may serve to compensate for inherent deficits in this system. One hypothetical model proposes that reward results from activation of mu-opioid receptors in the VTA and/or delta-receptor in the NAC; both these nuclei are targets of endogenous beta-endorphin. It is suggested that alcohol interferes with this reward pathway either directly or indirectly. The available experimental data accord well with those obtained from clinical studies which opioid antagonists have been used to prevent relapse in alcoholics. Conceptual considerations concerning communalities between various forms of addictions are also discussed in this review.

Role of immune processes in peripheral opioid analgesia

The experimental data clearly demonstrate that opioids (alkaloids as well as peptides) are able to inhibit nociception arising from inflamed tissue by a local peripheral action. mu- and delta- as well as kappa-opioid receptor ligands are effective by interaction with the respective opioid receptors presumably located in the terminal region of the sensory nerves. Similar effects are obtained when endogenous opioid peptides are released under stress conditions from immune cells present in the inflamed tissue. Immunoreactive beta-EP and enkephalins, processed in these cells, seem to be the relevant peptides in this respect. Although the mechanism of stress-induced release of opioid peptides from the immunocytes is presently not clear, there is indication that this process involves cytokines and CRF. Apart from immunological processes, inflammation-induced changes also take place at the level of the opioid receptors and are of significance in the manifestation of peripheral opioid antinociception; in particular the "activation" of these receptors apparently occurs at the early stages of inflammation when the infiltration of the tissue with immunocompetent cells is just beginning. There is increasing evidence for a therapeutic relevance of opioid-induced analgesia at peripheral sites of inflammation.

[Neurobiological principles of drug dependence. Exemplified by opioids and psychostimulants]

New insights into the neurobiological mechanisms underlying drug addition have become available with recent advances in experimental research. This is particularly true for the opioids and psychostimulants: behavioural and biochemical studies have revealed that activation of the mesolimbic "reward pathways", involving the release of dopamine, which acts upon D1 receptors, plays a critical part in the development of addictive behaviour. In the case of the opioids, the differentiation of various types of receptors (and of the corresponding endogenous ligands, the endorphins) revealed a bidirectional role of opioid receptors in this process: stimulation of the reward system, mediated by mu- and delta-opioid receptors, and inhibition of the reward pathways, mediated by the activation of chi-receptors. Thus, a functional equilibrium between these tonically active opioidergic systems appears to provide a neutral motivational state. During drug withdrawal, the decrease in dopamine release most probably reflects a disturbance of this equilibrium. There is increasing evidence that endogenous opioidergic mechanisms also modulate addictive behaviour caused by psychostimulants and other drugs of abuse. This article discusses the implications of these new findings in the context of pharmacotherapeutic strategies in the treatment of addictive behaviours.

The diagnosis of pulmonary tuberculosis by gaschromatographic detection of tuberculostearic acid using flame ionisation detectors

It has been shown that the detection of tuberculostearic acid (TBSA) with gas chromatography-mass-spectrometry provides a highly specific, sensitive and rapid method for the diagnosis of various forms of tuberculosis. However, the need for complex and expensive equipment prevented the more widespread use of this method. We report on the application of conventional gas chromatography with flame ionization detectors in the detection of TBSA in sputum samples. TBSA was detected in all patients with proven pulmonary tuberculosis before treatment or under treatment for less than 4 weeks (n = 18). Six of these patients (33%) had a negative microscopy result at the time of the study. Sputum samples from patients under therapy for longer than 4 weeks (n = 20) were TBSA-positive in 15 cases (75%). Only in two cases was the diagnosis by microscopy and/or culture not met by TBSA-detection. All sputa of 20 control patients with lung diseases other than tuberculosis were TBSA negative. Additional analysis of patients' data showed a significant relationship (P < 0.005) between the relative amounts of TBSA detectable in the sputum samples and the duration of therapy. It is concluded that conventional capillary gaschromatography may be sensitive and specific enough to be used for the detection of TBSA in sputum of patients with pulmonary tuberculosis.

Peripheral mechanisms of opioid antinociception in inflammation: involvement of cytokines

It has been shown previously that opioids induce antinociceptive effects at peripheral sites in the presence of inflammatory processes. Besides being elicited by local injection of opioids, such effects can also be obtained by activation of intrinsic opioid mechanisms, e.g. following stress. In the present study the possible role of cytokines in this mechanism was investigated. Unilateral inflammation of the hindpaw of rats was induced by local injection of Freund's complete adjuvant. Intraplantar injection of tumor necrosis factor alpha (TNF alpha) or interleukin-6 induced a dose-dependent increase in the threshold in the paw pressure test in the inflamed but not in the non-inflamed paw. This increase was prevented by local injection of naloxone and the mu-opioid receptor specific antagonist CTOP (D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH2) as well as by 3-E7, an universal opioid peptide antibody. In rats pretreated with cyclosporin A to suppress the immune system, the antinociceptive effect of TNF alpha was completely inhibited. In concert with previous studies these data indicate that the tested cytokines release opioid peptides (e.g. beta-endorphin and/or enkephalins) from immune cells of the inflamed tissue which act on opioid receptors present on sensory nerve terminals, resulting in antinociception.

Inflammation of the rat paw enhances axonal transport of opioid receptors in the sciatic nerve and increases their density in the inflamed tissue

The effect of inflammation, induced by unilateral intraplantar injection of Freund's adjuvant, on opioid receptors transported in the sciatic nerve and on opioid receptors present in the paw of the rat was studied by means of in vitro receptor autoradiography using [125I]beta-endorphin (human) as ligand. In the absence of inflammation, human beta-endorphin binding sites accumulated proximally and distally to a ligature placed on the sciatic nerve in a time-dependent manner, indicating bidirectional axonal transport. Some human beta-endorphin binding was also visible in non-inflamed paw tissue. Inflammation of the paw tissue massively increased human beta-endorphin binding on both sides of the sciatic nerve ligature and in the ipsilateral paw tissue. In inflamed paw tissue, beta-endorphin binding accumulated in the cutaneous nerve fibers as well as in the immune cells infiltrating the surrounding tissue. In the sciatic nerve and paw tissue, beta-endorphin binding was displaced by (D-Ala2, N-methyl-Phe4, Gly-ol5)enkephalin and (D-Pen2, D-Pen5)enkephalin, selective mu- and delta-opioid receptor agonists, respectively, and by the universal opioid antagonist naloxone, but not by U-50,488H, a k-selective receptor agonist. Taken together, these data provide neuroanatomical evidence for local inflammation-induced enhanced axonal transport of opioid receptors in rat sciatic nerve and accumulation in paw tissue.

Examination of the neurochemical substrates mediating the motivational effects of opioids: role of the mesolimbic dopamine system and D-1 vs. D-2 dopamine receptors

Both the reinforcing and aversive effects of exogenous opioids have been attributed to the activation of opioid receptors within the mesolimbic dopamine (DA) system. At present, however, it is unclear whether the activity of DA neurons projecting to the nucleus accumbens (NAC) is necessary for the expression of these effects. The present study sought to address this issue in rats by examining the influence of 6-hydroxydopamine (6-OHDA) lesions of the NAC and microinjections of selective DA receptor antagonists into this brain area upon the place conditioning produced by systemically administered opioids. The mu-opioid receptor agonist morphine produced dose-related preferences for the drug-paired place in control animals, whereas the kappa-opioid agonist U-69593 produced place aversions. Bilateral 6-OHDA lesions of the NAC abolished the place conditioning produced by both opioids. Lesions of the caudate/putamen or medial prefrontal cortex were, however, without effect. Microinjection of the D-1 DA antagonist SCH-23390 into the NAC, at a dose which was as ineffective as a conditioning stimulus, attenuated the place conditioning produced by low doses of morphine and U-69593. Over the dose range tested, the D-2 DA antagonist (-)-sulpiride was without effect. Neither SCH-23390 nor 6-OHDA lesions of the NAC modified the place conditioning produced by lithium chloride, a drug of a different pharmacological class. These data demonstrate that the rewarding and aversive effects of opioids are dependent on DA neural transmission within the mesolimbic system and suggest a role for NAC D-1 DA receptors in the mediation of both motivational effects.

Neuroanatomical sites mediating the motivational effects of opioids as mapped by the conditioned place preference paradigm in rats

An unbiased conditioned place preference paradigm was used to examine the neuroanatomical substrates mediating the reinforcing and aversive effects of mu and kappa opioid agonists. Unilateral microinjection of the selective mu agonist DAMGO into the ventral tegmental area (VTA), the origin of the mesolimbic and mesocortical dopamine (DA) systems, resulted in dose-dependent preferences for the drug-associated place. Intracranial injections of DAMGO into terminal projection sites of VTA DA neurons, the nucleus accumbens and the medial prefrontal cortex, however, as well as into the lateral hypothalamus, were without effect. In contrast, microinjections of the kappa agonist U50,488H and the dynorphin derivative E-2078 into the VTA produced place aversions. Place aversions were also observed after microinjections of U50,488H and E-2078 into the nucleus accumbens, medial prefrontal cortex and lateral hypothalamus. However, microinjections of mu and kappa agonists into either the origin of the mesostriatal DA system, the substantia nigra or into its major terminal field, the nucleus caudatus-putamen, was without effect. Autoradiographic studies revealed that the substances remained within a restricted area around the injection site, confirming that the effects observed were mediated therein. Thus, these data suggest an important role for the A10 neurons in the VTA in the regulation of both mu and kappa opioid-induced motivational states. The rewarding effects are associated with the activation of mu receptors in the VTA, whereas aversive effects are associated with the activation of kappa receptors in the VTA and its limbic-cortical terminal regions.

Effect of interpleural morphine on postoperative pain and pulmonary function after thoracotomy

We have investigated the effect of interpleural morphine on postoperative pain and pulmonary function after thoracotomy. At the end of surgery, an interpleural catheter was inserted in 17 patients and, in a double-blind and randomized manner, either a bolus of morphine 2.5 mg interpleurally (i.p.) and normal saline i.v. (group I) or, as a control for systemic absorption, morphine 2.5 mg i.v. and i.p. saline (group II) was injected. After the initial bolus, a continuous infusion of morphine 0.5 mg h-1 i.p. and saline i.v. (group I) or morphine 0.5 mg i.v. and saline i.p. (group II) was maintained for 24 h. Postoperative pain was assessed by a visual analogue scale, a numerical rating scale and the McGill Pain Questionnaire. Pulmonary function was assessed by spirometry. Supplementary analgesics, side effects, degree of sedation, vital signs and chest tube drainage were recorded. All variables were assessed on the day before surgery and 1, 2, 3, 4, 5, 6 and 24 h and 7 days after surgery. Supplementary morphine was given upon request. There was no significant difference in any pain measure or postoperative pulmonary function variable between the groups. We conclude that, after thoracotomy, interpleural morphine does not provide superior analgesia or improve pulmonary function compared with systemic morphine.

Dynorphin, a preferential ligand for κ-opioid receptors, is present in nerve fibers and immune cells within inflamed tissue of the rat

Exogenous kappa-opioid agonists have been shown to produce peripheral antinociceptive effects in inflamed tissue. This study sought to determine whether endogenous kappa-receptor ligands are present at the site of inflammation. In Freund's adjuvant-induced hindpaw inflammation in the rat, we show, by immunohistochemistry, that dynorphin is detectable within inflammatory cells and in the cutaneous nerves in a similar distribution as calcitonin gene-related peptide, a specific marker for sensory neurons. These findings extend our previous observations in that not only beta-endorphin and Met-enkephalin (mu- and delta-receptor ligands), but also a preferential kappa-ligand is present within inflamed subcutaneous tissue.

Gene expression and localization of opioid peptides in immune cells of inflamed tissue: functional role in antinociception

Our previous studies indicate that endogenous opioids (primarily beta-endorphin) released during stressful stimuli can interact with peripheral opioid receptors to inhibit nociception in inflamed tissue of rats. This study sought to localize opioid precursor mRNAs and opioid peptides deriving therefrom in inflamed tissue, identify opioid containing cells and demonstrate their functional significance in the inhibition of nociception. In rats with Freund's adjuvant-induced unilateral hindpaw inflammation we show that: (i) pro-opiomelanocortin and proenkephalin-mRNAs (but not prodynorphin mRNA) are abundant in cells of inflamed, but absent in non-inflamed tissue; (ii) numerous cells infiltrating the inflamed subcutaneous tissue are stained intensely with beta-endorphin and [Met]enkephalin (but only few scattered cells with dynorphin) antibodies; (iii) beta-endorphin is present in T- and B-lymphocytes, monocytes and macrophages; and (iv) whole-body irradiation suppresses stress-induced antinociception in the inflamed paw. Taken together, these data suggest that endogenous opioid peptides are synthesized and processed within various types of immune cells at the site of inflammation. Immunosuppression abolishes the intrinsic antinociception in inflammatory tissue confirming the functional significance of these cells.

Opposing tonically active endogenous opioid systems modulate the mesolimbic dopaminergic pathway

The mesolimbic dopaminergic system has been implicated in mediating the motivational effects of opioids and other drugs of abuse. The site of action of opioids within this system and the role of endogenous opioid peptides in modulating dopamine activity therein remain unknown. Employing the technique of in vivo microdialysis and the administration of highly selective opioid ligands, the present study demonstrates the existence of tonically active and functionally opposing mu and kappa opioid systems that regulate dopamine release in the nucleus accumbens, the major terminal area of A10 dopaminergic neurons. Thus, stimulation of mu-type receptors in the ventral tegmental area, the site of origin of A10 dopaminergic neurons, increases dopamine release whereas the selective blockade of this opioid receptor type results in a significant decrease in basal dopamine release. In contrast, stimulation of kappa-type receptors within the nucleus accumbens decreases dopamine release whereas their selective blockade markedly increases basal dopamine release. These data show that tonic activation of mu and kappa receptors is required for the maintenance of basal dopamine release in the nucleus accumbens. In view of the postulated role of the mesolimbic system in the mediation of drug-induced alterations in mood and affect, such findings may have implications for the treatment of opiate dependence and affective disorders.

[Opiate addiction. Pharmacologic and biochemical aspects]

The detailed information now available regarding the neurobiology of opiates (opioids) has contributed greatly to our understanding of opioid addiction. This in turn has permitted a more complete understanding of the processes underlying drug addiction. Opioid agonists with a high affinity for mu- or delta-receptors produce conditioned preferences for an environment previously associated with their administration, whereas kappa-agonists induce place aversions. Studies in which opioids were microinjected into discrete brain areas suggest that these opposing motivational effects are mediated via an interaction with the mesolimbic dopamine (DA) system originating in the midbrain. Microdialysis studies have clearly shown that mu-agonists preferentially increase DA release and metabolism in the Nucleus accumbens, whereas kappa-receptor agonists decrease release. Opposite effects on DA are observed in response to microinjections of selective antagonists for these receptor types, suggesting the existence of tonically active endogenous opioid systems which maintain DA release in the mesolimbic system: a continuous "reward" tone, probably mediated by beta-endorphin in the ventral tegmentum of the midbrain and an "aversive" tone, mediated by dynorphin in the Nucleus accumbens. Aspects of such a bidirectional regulation of the mesolimbic system by endogenous opioids are discussed.

Paradoxical effect of chronic fentanyl treatment on naltrexone-induced supersensitivity and upregulation

The present study sought to evaluate the influence of chronic opioid antagonist treatment upon the discriminative stimulus and analgesic effects of the opioid receptor agonist fentanyl. Male Wistar rats were trained to discriminate fentanyl (0.04 mg/kg) from saline in a two-lever food reinforced paradigm. After acquisition of the discrimination, they were implanted with osmotic minipumps which delivered either naltrexone (0.07 mg/h) or distilled water, and the sensitivity of discrimination was assessed at various times after pump removal. The influence of chronic naltrexone treatment upon the antinociceptive effects of fentanyl was assessed in drug-naive (control) rats and in rats which had received fentanyl in the same dosage schedule as those in drug discrimination experiments. Chronic infusion of naltrexone for 7 days did not modify the dose-response curve for the fentanyl vs. saline discrimination. Algesiometric tests revealed a significant increase in the antinociceptive effect of fentanyl in control rats after naltrexone treatment. In contrast, such supersensitivity was not observed in rats which had previously received fentanyl injections. Autoradiographic data revealed a naltrexone-induced upregulation of mu opioid receptors in control animals. Paradoxically, this effect was significantly increased in fentanyl-pretreated rats. These data suggest that prior drug experience can affect the development of antagonist-induced supersensitivity to the behavioral actions of opioid agonists. Furthermore, it would appear that after chronic agonist treatment the phenomena of opioid receptor upregulation and functional supersensitivity are dissociated.

Prolonged inflammatory pain modifies corticotropin-releasing factor-induced opioid peptide release in the hypothalamus

The influence of prolonged pain upon hypothalamic opioid peptide release in vitro was examined in rats subjected to Freund's adjuvant (FA)-induced unilateral inflammation of the hindlimb. Basal release of enkephalin (ENK) but not beta-endorphin (END) or dynorphin (DYN) was increased 10 days following FA treatment. Superfusion of corticotropin-releasing factor (CRF; 10(-8) M) stimulated the release of opioid peptides in control hypothalami. CRF, however, failed to modify beta-END and DYN release in hypothalami of FA-treated rats, whereas ENK release was markedly reduced. In contrast, KCl-stimulated opioid peptide release did not differ between FA and control hypothalami. These data demonstrate that prolonged inflammatory pain alters the responsiveness of hypothalamic opioid systems to CRF. It is suggested that this effect is mediated at the level of the CRF neuron or its receptor.

Analgesic effect of intraarticular morphine after arthroscopic knee surgery

BACKGROUND

Opioids can produce potent antinociceptive effects by interacting with local opioid receptors in inflamed peripheral tissue. In this study we examined the analgesic effects of the intraarticular, as compared with intravenous, administration of morphine after arthroscopic knee surgery.

METHODS

In a double-blind, randomized trial, we studied 52 patients who had received one of four injections at the end of surgery. The patients in group 1 (n = 18) received 1 mg of morphine intraarticularly and saline intravenously; those in group 2 (n = 15), saline intraarticularly and 1 mg of morphine intravenously; those in group 3 (n = 10), 0.5 mg of morphine intraarticularly and saline intravenously; and those in group 4 (n = 9), 1 mg of morphine and 0.1 mg of naloxone intraarticularly and saline intravenously. The volume of the intraarticular injections was 40 ml, and that of the intravenous injections was 1 ml. After 1, 2, 3, 4, 6, and 24 hours, postoperative pain was assessed with a visual-analogue scale, a numerical-rating scale, and the McGill pain questionnaire. The need for supplemental analgesic agents, the patients' vital signs, and the occurrence of side effects were monitored.

RESULTS

All pain scores were lower in group 1 than in group 2 at all times. The differences were significant (P less than 0.05) at three, four, and six hours (mean [+/- SD] visual-analogue score at six hours, 9 +/- 13 mm vs. 37 +/- 31 mm). The mean (+/- SD) consumption of supplemental analgesic medication per 24 hours was significantly lower in group 1 (36 +/- 51 mg of diclofenac and 1.2 +/- 3.4 mg of meperidine) than in group 2 (75 +/- 42 mg of diclofenac and 14 +/- 18 mg of meperidine, P less than 0.05). The visual-analogue scores in group 3 were slightly but not significantly higher than those in group 1 at all times except 6 and 24 hours after injection. The visual-analogue scores were significantly higher in group 4 than in group 1 one to four hours after injection (P less than 0.05), indicating that the analgesic effect of intraarticular morphine was reversible by naloxone.

CONCLUSIONS

Low doses of intraarticular morphine can significantly reduce pain after knee surgery through an action specific to local opioid receptors that reaches its maximal effect three to six hours after injection.

Modulation of the mesolimbic dopaminergic system by beta-endorphin-(1-27) as assessed by microdialysis

In the present study we used in vivo microdialysis to examine the influence of beta-endorphin-(1-27) (beta-EP-(1-27) upon beta-endorphin (beta-EP)-induced dopamine (DA) release in the nucleus accumbens of anesthetized rats. Microdialysis probes were inserted into the nucleus accumbens and perfusates were analyzed for DA and its metabolites, dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), using a reversed-phase HPLC system with electrochemical detection. Intracerebroventricular (i.c.v.) administration of beta-EP-(1-27) (5-20 micrograms) resulted in a dose-dependent increase in DA release which was smaller than the beta-EP-induced DA release, whereas metabolite levels were not altered. Pretreatment with beta-EP-(1-27) (5-20 micrograms) significantly altered the beta-EP (5 micrograms)-induced increase in DA release. These results indicate that beta-EP-(1-27) antagonizes the beta-EP-induced release of DA in the nucleus accumbens. In addition to its antagonistic properties at the beta-endorphin binding site, beta-EP-(1-27) appears to be a partial agonist, inducing increased DA release. These findings suggest a regulatory function for this naturally occurring beta-EP fragment within the mesolimbic system.

Influence of chronic lithium treatment upon the motivational effects of opioids: alteration in the effects of mu- but not kappa-opioid receptor ligands

The influence of chronic lithium (Li) treatment upon the secondary reinforcing effects of opioid agonists and antagonists was examined by use of an unbiased place preference conditioning procedure. Administration of the mu-agonist morphine to control rats resulted in marked preferences for the drug-associated place and a similar effect was observed in response to the psychostimulant d-amphetamine. In contrast, the selective kappa-opioid agonist U-69593 [(5 alpha,7 alpha,8 beta)-(-)-N-methyl-N-(7-1(pyrrolidinyl-1-oxaspirol(4,5) dec-8-yl benzeneacetamide)] and the opioid antagonist naloxone produced dose-related place aversions. Chronic administration of a Li-containing diet, which produced serum levels of 0.56 mmol/l, abolished the place preferences induced by morphine but not d-amphetamine. This treatment abolished the aversive effects of naloxone but did not modify those produced by U-69593. These data and those from a previous place conditioning study indicate that Li can function as an antagonist of mu-opioid receptor ligands in vivo and that this action underlies its motivational effects. Furthermore, the inability of chronic Li treatment to modify either the content or basal release of beta-endorphin in various brain regions suggests that this antagonism is mediated directly at the level of the opioid receptor and/or its transducer systems.

Beta-endorphin-induced locomotor stimulation and reinforcement are associated with an increase in dopamine release in the nucleus accumbens

In vivo microdialysis was used to compare the effects of beta-endorphin upon dopamine (DA) release in the nucleus accumbens (NAC) of anesthetized versus freely moving rats, and to examine the role of the mesolimbic DA system in mediating both the motoric and secondary reinforcing effects of this peptide. Microdialysis probes were inserted into the NAC and perfusates were analyzed for DA and its metabolites, dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), using a reversed phase HPLC system with electrochemical detection for separation and quantification. Intracerebroventricular (ICV) administration of beta-endorphin (2.5 and 5.0 micrograms) increased DA release and metabolites in both freely moving and anesthetized rats. This effect was of greater magnitude and duration in freely moving rats and was accompanied by stimulation of locomotor activity. The 5 micrograms dose also functioned as a secondary reinforcer in a conditioned place preference paradigm. A higher dose of beta-endorphin (7.5 micrograms) stimulated DA release and metabolites in anesthetized rats but failed to affect these parameters in freely moving rats. At this dose, catalepsy and a loss of the reinforcing effects of this peptide were observed. These data demonstrate marked differences in the effects of beta-endorphin upon DA release in the awake versus anesthetized rat. Further, the finding that the reinforcing and locomotor stimulating effects of beta-endorphin only occur at those doses which stimulate DA release suggest that this action is critical for the expression of both behavioral effects.

Neuroanatomical substrates mediating the aversive effects of D-1 dopamine receptor antagonists

An unbiased place preference conditioning procedure was used to examine the secondary reinforcing effects of selective D-1 dopamine (DA) receptor antagonists and the neuroanatomical substrates mediating these effects. Systemic administration of SCH-23390 or the non-benzazepine D-1 receptor antagonist A-69024 produced dose-related conditioned aversions for the drug-associated place. In contrast, the D-2 antagonists spiperone and (-)sulpiride were without effect. SCH-23390-induced place aversions were also observed after intracerebroventricular administration. The minimum dose producing this effect was significantly lower than that after systemic injection. Aversive effects were also observed after microinjection of SCH-23390 into the n. accumbens. In contrast, microinjections of this antagonist into the ventral tegmental area, caudate putamen or medial prefrontal cortex were without effect. These data confirm that the blockade of D-1 but not D-2 DA receptors induces aversive states. Furthermore, they suggest that D-1 receptors in the n. accumbens may play an important role in the regulation of non-drug induced affective states.

Fatty acid analysis of different Candida species by capillary column gas-liquid chromatography

Gas-liquid chromatography was used to analyse the fatty acid composition of whole-cell hydrolysates of 40 yeast strains representing 5 Candida species and Torulopsis glabrata, T. glabrata could be easily distinguished from all other Candida spp. by the absence of C18:3. Candida albicans, C. krusei, C. parapsilosis, C. pseudotropicalis and C. tropicalis showed 10 major peaks in characteristic proportions. C. parapsilosis showed a high C16:0/C16:1 ratio (greater than 4.5), whereas C. pseudotropicalis was characterized by a C18:1/C16:0 ratio of less than 2.0. A high C18:3 concentration (greater than 10%) was typical for C. krusei (C18:2/C18:3 ratio less than or equal to 1.0). Our data reveal characteristic patterns of cellular fatty acid composition of T. glabrata, C. krusei, C. parapsilosis and C. pseudotropicalis which can be used for laboratory identification.