Can Simulated Microgravity and Darkness Conditions Influence the Phytochemical Content and Bioactivity of the Sprouts?-A Preliminary Study on Selected Fabaceae Species.

Sprouts' consumption has become popular due to their wide availability, easy cultivation process, and proven biological activity. Moreover, stress factors, such as limited access to light or disturbed gravity during growth, may contribute to the increased activity and the synthesis of bioactive compounds. In this study, for the first time, the examination of the impact of darkness and simulated microgravity conditions on the white clover sprouts from the Fabaceae family was conducted. Among several species, used in the preliminary attempts, only white clover was satisfactory sprouting in the disturbed gravity conditions, and thus was chosen for further examination. A random positioning machine setup was used during the cultivation process to simulate microgravity conditions. Additionally, the sprouts were cultivated in total darkness. Simulated microgravity and/or darkness during the first few days of the sprouts' growth caused biomass reduction, the increased synthesis of bioactive compounds (isoflavones and phenolics), and changes in the level of abscisic acid and phenylalanine ammonia-lyase. Moreover, it increased the antioxidant properties of the sprouts, while the enhancement of their cytotoxic impact was observed only for androgen-dependent prostate cancer LNCaP cells. To conclude, the presented results are promising in searching for novel functional food candidates and further studies are necessary, directed at other plant families.

The Role of Metacognition in the Prediction of Depressive and Anxiety Symptoms in Chronically Ill Patients.

INTRODUCTION: Cancer, diabetes, and heart diseases are frequent causes of depression and anxiety. The study explored the metacognitive beliefs manifested by chronically ill patients and the presence of depressive or anxiety symptoms and the predictive role of metacognition in both. METHODS: A total of 254 chronically ill patients participated in the study. The Metacognitive Questionnaire was used to measure the patients' metacognitive beliefs, whereas the Hospital Anxiety and Depression Scale was applied to evaluate their psychopathological symptoms. A correlation analysis was performed to explore the relationships between metacognition and psychopathological symptoms. Regression analyses were conducted to examine the predictive role of metacognition in anxiety and depression. RESULTS: The Negative Beliefs about Uncontrollability and Danger scale correlated with both anxiety and depression scales, and the Cognitive Confidence scale correlated with the depression scale. Linear regression analyses indicated that metacognitive beliefs were responsible for 32.2% of the variance of anxiety symptoms among all the chronically ill. Metacognitive beliefs accounted for 48.8% of the variance in anxiety symptoms and 36.6% in depressive symptoms among diabetes patients. CONCLUSIONS: There are specific correlations between psychopathological symptoms and metacognition among chronically ill patients. Metacognitions have a moderate role in developing and sustaining anxiety and depressive symptoms.

Dissociation constants of relevant secondary organic aerosol components in the atmosphere.

The presented studies focus on measuring the determination of the acidity constant (pKa) of relevant secondary organic aerosol components. For our research, we selected important oxidation products (mainly carboxylic acids) of the most abundant terpene compounds, such as α-pinene, ß-pinene, ß-caryophyllene, and δ-3-carene. The research covered the synthesis and determination of the acidity constant of selected compounds. We used three methods to measure the acidity constant, i.e., 1H NMR titration, pH-metric titration, Bates-Schwarzenbach spectrophotometric method. Moreover, the pKa values were calculated with Marvin 21.17.0 software to compare the experimentally derived values with those calculated from the chemical structure. pKa values measured with 1H NMR titration ranged from 3.51 ± 0.01 for terebic acid to 5.18 ± 0.06 for ß-norcaryophyllonic acid. Moreover, the data determined by the 1H NMR method revealed a good correlation with the data obtained with the commonly used potentiometric and UV-spectroscopic methods (R2 = 0.92). In contrast, the comparison with in silico results exhibits a relatively low correlation (R2Marvin = 0.66). We found that most of the values calculated with the Marvin Program are lower than experimental values obtained with pH-metric titration with an average difference of 0.44 pKa units. For di- and tricarboxylic acids, we obtained two and three pKa values, respectively. A good correlation with the literature values was observed, for example, Howell and Fisher (1958) used pH-metric titration and measured pKa1 and pKa2 to be 4.48 and 5.48, while our results are 4.24 ± 0.10 and 5.40 ± 0.02, respectively.

The Malaprade reaction mechanism for ethylene glycol oxidation by periodic acid based on density functional theory (DFT).

A general mechanism of the Malaprade oxidative carbon-carbon bond cleavage reaction of α-glycol in the presence of periodic acid has been proposed on the basis of density functional theory (DFT) computations. Ethylene glycol and periodic acid, both in their neutral forms, have been studied as noble substrate representatives in model reactions. The proposed reaction mechanism has been constructed based on and compared with previously published experimental kinetic, spectroscopic and temperature and pH-dependent studies. In the presented theoretical mechanistic considerations, four alternative molecular transformations have been analyzed from thermodynamic and kinetic points of view. Theoretically, the predicted activation energy barriers have been compared with experimental ones published elsewhere. The presented minimum energy pathway (MEP) unveiled the shape and conformation of the intermediate and transition state structures. The three-step reaction process involves the formation of a seven-membered quasi-ring assisted by an intramolecular hydrogen-bond intermediate structure forming one I-O bond (IC1_B), a cyclic ester intermediate forming two I-O bonds (IC2_C) and the final products formed at the two very last stages (HIO3, water and two formaldehyde molecules). The computed and energetically the most favourable reaction landscape proposed in this work uniforms and refines the mechanistic proposition given by Criegee for Malaprade type of reactions and further gives a detailed molecular understanding of the reaction rate and atomic connections en route the transformation. The molecular geometries of all stationary points (intermediate and transition state structures) lying on the potential energy hypersurface have been optimized at the four alternative DFT levels under the solvation model based on the density approximation: B3PW91, CAM-B3LYP, BMK, ωB97XD. The 6-311+G(2d,p) basis set for C, O, and H atoms and both the full (DGDZVP) and Ahlrichs-Weigend1 (def2-TZVP) basis sets for iodine atoms were used during the computations.

The Impact of Harsh Stratospheric Conditions on Survival and Antibiotic Resistance Profile of Non-Spore Forming Multidrug Resistant Human Pathogenic Bacteria Causing Hospital-Associated Infections.

Bacteria are constantly being lifted to the stratosphere due to air movements caused by weather phenomena, volcanic eruptions, or human activity. In the upper parts of the atmosphere, they are exposed to extremely harsh and mutagenic conditions such as UV and space radiation or ozone. Most bacteria cannot withstand that stress, but for a fraction of them, it can act as a trigger for selective pressure and rapid evolution. We assessed the impact of stratospheric conditions on the survival and antibiotic resistance profile of common non-spore-forming human pathogenic bacteria, both sensitive and extremely dangerous multidrug-resistant variants, with plasmid-mediated mechanisms of resistance. Pseudomonas aeruginosa did not survive the exposure. In the case of strains that were recovered alive, the survival was extremely low: From 0.00001% of Klebsiella pneumoniae carrying the ndm-1 gene and methicillin-resistant Staphylococcus aureus mecA-positive with reduced susceptibility to vancomycin (MRSA/VISA), to a maximum of 0.001% of K. pneumoniae sensitive to all common antibiotics and S. aureus sensitive to vancomycin (MRSA/VSSA). We noticed a tendency towards increased antibiotic susceptibility after the stratospheric flight. Antimicrobial resistance is a current real, global, and increasing problem, and our results can inform current understandings of antibiotic resistance mechanisms and development in bacteria.

Lifestyle Changes among Polish University Students during the COVID-19 Pandemic.

Students worldwide have been impacted by nationwide safety closures due to the COVID-19 pandemic, creating an environment with loss of interaction with colleagues, social isolation, boredom, and economic uncertainty. Since university students were considered uniquely vulnerable to mental health problems even before the pandemic, this study aimed to investigate lifestyle and behavioral changes experienced by this population due to the epidemiological situation and their effect on their mental health. Data were collected via an online survey conducted among university students across Poland. The survey addressed recent lifestyle changes that were a result of the pandemic as well as psychological distress, symptoms of insomnia and symptoms of post-traumatic stress. The results indicate that protective factors include maintaining a daily routine, staying physically active, following a usual eating pattern and taking care of sleep hygiene. Changes in behavior contributing to poorer mental health included giving up a daily routine, neglecting meals, tidiness, hygiene as well as social relationships, changes in food intake, sleeping schedule, a decrease in physical activity and the onset of sexual dysfunctions. A history of psychiatric treatment and an increase in self-harm as well as an increase in alcohol and tobacco consumption were also found to be associated with psychological distress. Experienced lifestyle and behavioral changes and their impact on mental health were apparent throughout the obtained data, highlighting the need for psychological support in the studied population. Based on the results we were able to establish a list of protective and risk factors influencing the everyday life and psychological wellbeing of students amidst the COVID-19 pandemic, which could also be translated into life skills.

Class of 2020 in Poland: Students' Mental Health during the COVID-19 Outbreak in an Academic Setting.

The COVID-19 pandemic had led universities to introduce lockdowns, which has led to significant shifts in students' lives. Classes were moved online, students had to leave dorms and move; they had to forgo regular meetings with their peers. Subsequently, a vital demand for examining students' mental health emerged. The data were collected at a time when universities in Poland were under lockdowns. Participants represented students of many different fields of study. The General Health Questionnaire (GHQ-28) was used. Student's subjective evaluation of online learning and their adaptation to academic life shifts were reviewed. A total of 1123 participants took part in this study. Relationship analysis included tests, such as U Mann-Whitney, appropriate for specific variables. The impact of variables connected with the pandemic on the GHQ scores was tested using multivariate regression analysis. The results were considered significant at a p-value set at 0.05. Overall, 76.96% of the participants manifested psychopathological symptoms measured by the GHQ. Four demographical variables were possibly associated with the GHQ scores: female sex, living in a big city, necessity to move back home, and being in a relationship. Negative correlations between subjective evaluation of variables concerning e-learning, such as its efficiency or quality, and the GHQ scores were found. Some variables were found to be potential protective factors, whereas others could have contributed to worsened mental health. The study provides data on students' worsened mental health due to the COVID-19 pandemic and the shifts in academic life it caused. Therefore, recommendations for early psychosocial interventions among students are strongly advised.

Coping Styles, Mental Health, and the COVID-19 Quarantine: A Nationwide Survey in Poland.

Background: The outbreak of the novel coronavirus COVID-19 that began from March 2020 is yet to be contained. Consequences of the ongoing pandemic may have a negative impact on the mental health of affected individuals. This particularly refers to those quarantined. Since the COVID-19 pandemic is currently one of the biggest health issues worldwide, a higher demand emerges for research concentrating on the worsening of psychological well-being among the general and the quarantined population, as well as on individual coping strategies that may moderate the occurrence of psychopathologies. Method: Data were collected within the first weeks of the COVID-19 pandemic in Poland. Participants represented quarantine (+) and quarantine (-) groups. Quarantine (+) group, different from quarantine (-), consisted of people who experienced it themselves or someone close to them did after contacting an infected individual. To measure psychopathological symptoms a General Health Questionnaire (GHQ-28) was used. For measuring PTSD symptoms, the Impact of Event Scale-Revised (IES-R) was used. This study followed the coping strategies manifested among the participants using the MiniCope questionnaire. Results: A total of 2,036 individuals participated in this study. Quarantine (+) individuals had significantly higher total and subscales GHQ-28 scores (anxiety, insomnia, and somatic symptoms) as well as a higher IES-R arousal score. The quarantine (+) individuals were more likely to use self-distraction as a coping strategy. This research identified positive and negative correlations between presented coping styles and manifested psychopathology. Conclusion: This nationwide study suggests occurrence of negative effects on mental health due to the COVID-19 pandemic and quarantine. It is observed on most of the measured psychopathological symptoms. The present research provides a line of action that should be followed in the future in case of another epidemic and in the event restrictions like quarantine have to be introduced again.

Toxicological Responses of α-Pinene-Derived Secondary Organic Aerosol and Its Molecular Tracers in Human Lung Cell Lines.

Secondary organic aerosol (SOA) is a major component of airborne fine particulate matter (PM2.5) that contributes to adverse human health effects upon inhalation. Atmospheric ozonolysis of α-pinene, an abundantly emitted monoterpene from terrestrial vegetation, leads to significant global SOA formation; however, its impact on pulmonary pathophysiology remains uncertain. In this study, we quantified an increasing concentration response of three well-established α-pinene SOA tracers (pinic, pinonic, and 3-methyl-1,2,3-butanetricarboxylic acids) and a full mixture of α-pinene SOA in A549 (alveolar epithelial carcinoma) and BEAS-2B (bronchial epithelial normal) lung cell lines. The three aforementioned tracers contributed ∼57% of the α-pinene SOA mass under our experimental conditions. Cellular proliferation, cell viability, and oxidative stress were assessed as toxicological end points. The three α-pinene SOA molecular tracers had insignificant responses in both cell types when compared with the α-pinene SOA (up to 200 µg mL-1). BEAS-2B cells exposed to 200 µg mL-1 of α-pinene SOA decreased cellular proliferation to ∼70% and 44% at 24- and 48-h post exposure, respectively; no changes in A549 cells were observed. The inhibitory concentration-50 (IC50) in BEAS-2B cells was found to be 912 and 230 µg mL-1 at 24 and 48 h, respectively. An approximate 4-fold increase in cellular oxidative stress was observed in BEAS-2B cells when compared with untreated cells, suggesting that reactive oxygen species (ROS) buildup resulted in the downstream cytotoxicity following 24 h of exposure to α-pinene SOA. Organic hydroperoxides that were identified in the α-pinene SOA samples likely contributed to the ROS and cytotoxicity. This study identifies the potential components of α-pinene SOA that likely modulate the oxidative stress response within lung cells and highlights the need to carry out chronic exposure studies on α-pinene SOA to elucidate its long-term inhalation exposure effects.

Correction to "Physicochemical Properties of Terebic Acid, MBTCA, Diaterpenylic Acid Acetate, and Pinanediol as Relevant α-Pinene Oxidation Products".

[This corrects the article DOI: 10.1021/acsomega.9b04231.].

Physicochemical Properties of Terebic Acid, MBTCA, Diaterpenylic Acid Acetate, and Pinanediol as Relevant α-Pinene Oxidation Products.

The physicochemical properties and the synthesis of four α-pinene oxidation products, terebic acid, 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA), diaterpenylic acid acetate (DTAA), and pinanediol, are presented in this study. The physicochemical properties encompass thermal properties, solubility in water, and dissociation constant (pK a) for the investigated compounds. It was found that terebic acid exhibits a relatively high melting temperature of 449.29 K, whereas pinanediol revealed a low melting temperature of 329.26 K. The solubility in water was determined with the dynamic method and the experimental results were correlated using three different mathematical models: Wilson, NRTL, and UNIQUAC equations. The results of the correlation indicate that the Wilson equation appears to work the best for terebic acid and pinanediol. The calculated standard deviation was for 3.79 for terebic acid and 1.25 for pinanediol. In contrast, UNIQUAC was the best mathematical model for DTAA and MBTCA. The calculated standard deviation was 0.57 for DTAA and 2.21 for MBTCA. The measured water solubility increased in the following order: pinanediol > DTAA ≥ MBTCA > terebic acid, which affects their multiphase aging chemistry in the atmosphere. Moreover, acidity constants (pK a) at 298, 303, and 308 K were determined for DTAA with the Bates-Schwarzenbach spectrophotometric method. The pK a values obtained at 298, 303, and 308 K were found to be 3.76, 3.85, and 3.88, respectively.

Organic Hydroxy Acids as Highly Oxygenated Molecular (HOM) Tracers for Aged Isoprene Aerosol.

Highly oxygenated molecules (HOMs) are a class of compounds associated with secondary organic aerosols exhibiting high oxygen to carbon (O:C) ratios and often originating from the oxidation of biogenic compounds. Here, the photooxidation and ozonolysis of isoprene were examined under a range of conditions to identify HOM tracers for aged isoprene aerosol. The HOM tracers were identified as silylated derivatives by gas chromatography-mass spectrometry and by detecting their parent compounds by liquid chromatography-high resolution mass spectrometry. In addition to the previously observed methyltetrols and 2-methylglyceric acid, seven tracer compounds were identified, including 2-methyltartronic acid (MTtA), 2-methylerythronic acid (2MeTrA), 3-methylerythronic acid (3MeTrA), 2-methylthreonic acid (2MTrA), 3-methylthreonic acid (3MTrA), erythro-methyltartaric acid (e-MTA), and threo-methyltartaric acid (t-MTA). The molecular structures were confirmed with authentic standards synthesized in the laboratory. The presence of some of these HOMs in the gas and particle phases simultaneously provides evidence of their gas/particle partitioning. To determine the contributions of aged isoprene products to ambient aerosols, we analyzed ambient PM2.5 samples collected in the southeastern United States in summer 2003 and at two European monitoring stations located in Zielonka and Godów (Poland). Our findings show that methyltartaric acids (MTA) and 2- and 3-methylthreonic acids (and their stereoisomers) are representative of aged isoprene aerosol because they occur both in the laboratory chamber aerosol obtained and in ambient PM2.5. On the basis of gas chromatography-mass spectrometry (GC-MS) analysis, their concentrations were found to range from 0.04 ng for 3-methylthreonic acid to 6.3 ng m-3 for methyltartaric acid at the southeast site in Duke Forest, NC, USA.

Physicochemical Properties of Pinic, Pinonic, Norpinic, and Norpinonic Acids as Relevant α-Pinene Oxidation Products.

Here, the study is focused on the synthesis and determination of physicochemical properties of four α-pinene secondary organic aerosol (SOA) products: cis-pinic acid, cis-pinonic acid, cis-norpinic acid, and cis-norpinonic acid. These encompass their thermal properties, solid-liquid phase equilibria, and dissociation constant (pKa). Thermal properties, including the melting temperature, enthalpy of fusion, temperature, and enthalpy of the phase transitions, were measured with the differential scanning calorimetry technique. These SOA components exhibit relatively high melting temperatures from 364.32 K for cis-pinic acid to 440.68 K for cis-norpinic acid. The enthalpies of fusion vary from 14.75 kJ·mol-1 for cis-norpinic acid to 30.35 kJ·mol-1 for cis-pinonic acid. The solubility in water was determined with the dynamic method (solid-liquid phase equilibria method), and then experimental results were interpreted and correlated using three different mathematical models: Wilson, non-random two-liquid model, and universal quasichemical equations. The results of the correlation indicate that the Wilson equation appears to work the best for all investigated compounds, giving rise to the lowest value of a standard deviation. cis-Norpinic acid and cis-pinic acid (dicarboxylic acids) show better solubility in the aqueous solution than cis-norpinonic acid and cis-pinonic acid (monocarboxylic acids), which affect the multiphase chemistry of α-pinene SOA processes. For cis-pinonic acid and cis-norpinonic acid, also pH-profile solubility was determined. The intrinsic solubility (S0) for cis-norpinonic acid was measured to be 0.05 mmol·dm-3, while for cis-pinonic acid, it was found to be 0.043 mmol·dm-3. The acidity constants (pKa) at 298 and 310 K using the Bates-Schwarzenbach spectrophotometric method were determined. The pKa values at 298.15 K for cis-norpinonic acid and cis-pinonic acid were found to be 4.56 and 5.19, respectively, whereas at 310.15 K, pKa values were found to be -4.76 and 5.25, respectively.

Negative body image in breast cancer patients.

The aim of this overview study is to familiarize readers with the impact of changes to body image (BI) among patients treated for breast cancer. Body image is subjected to many changes during oncological treatment and every method of treatment (surgery, chemotherapy, radiotherapy, and hormone therapy) can have a negative impact on the way the treated patients perceive their bodies. The article differentiates the susceptibility of patients to a worsened self-image due to their pre-disease personality, socioeconomic factors, age, and declared sense of control during the oncological treatment. Herein, the areas of patients' lives which are the most affected by negative BI are discussed: quality of life and functioning in society, with particular emphasis on the return to work and sexuality. The ways of protecting patients' BI throughout treatment which have been proposed in the literature are presented in conclusions.

Tandem Palladium-Catalyzed 6- exo- dig Oxocyclization Coupling of δ-Acetylenic ß-Ketoesters with Aryl Bromides and Chlorides: Route to Substituted Dihydropyrans.

We report an efficient and functional group-tolerant method for the synthesis of substituted dihydropyrans, based on tandem Pd-catalyzed cyclization/coupling of δ-acetylenic ß-ketoesters with aryl halides. The reaction proceeds cleanly through 6- exo-dig oxocyclizaton mode, delivering products with very good yields and complete control of regio- and stereoselectivity. Due to mild conditions, the transformation offers exceptional tolerance of functionalities, including NHR, formyl, enolizable ketone, free OH and NH2 groups, as well as a range of N-heterocyclic moieties of potential biological relevance.

Physical and Chemical Properties of 3-Methyl-1,2,3-butanetricarboxylic Acid (MBTCA) Aerosol.

The properties and the chemical fate of later generation products of the oxidation of biogenic organic compounds are mostly unknown. The properties of fresh MBTCA aerosol, a later generation product of the oxidation of monoterpenes in the atmosphere, were determined combining an aerosol mass spectrometer (AMS), a thermodenuder, and a scanning mobility particle sizer. Based on its AMS spectrum m/z 141.055 (C7H9O3+) could be used as an MBTCA signature. The MBTCA particle density was 1.43 ± 0.04 g cm-3, its saturation concentration was (1.8 ± 1.3) × 10-3 µg m-3 at 298 K, and its vaporization enthalpy was 150 ± 15 kJ mol-1. After OH radical exposure (∼1.2 days) and UV illumination the average aerosol O:C ratio decreased from 0.72 to 0.58-0.64 suggesting net fragmentation. Our findings suggest that the reactions of MBTCA with OH lead to CO2 loss with or without an oxygen addition.

Bioaccumulation and toxicity studies of macroalgae (Charophyceae) treated with aluminium: Experimental studies in the context of lake restoration.

The objective of this study was to examine the impact of aluminium on the perennial macroalgae Chara hispida L. and its bioaccumulation capacities. Aluminium (Al) was introduced into the environment in the form of polyaluminium chloride, an agent utilized in the restoration of waterbodies. Research was conducted in an experimental setting using mesocosms (volume 0.8m3) placed in the littoral zone of a lake with C. hispida. Three doses of the coagulant were applied, each with a different volume: low - 6.1g Al m-3, medium - 12.2gm-3 and high - 24.5g Al m-3. A significant acidification of environment was determined, which would imply the presence of toxic Al3+ ions. It has been demonstrated that aluminium penetrates and accumulates in the cells of the charophyte. This caused damage to the thalli, which manifested itself in chloroses, necroses, flaking of the cortex cells and softening of the thallus, whose severity was proportionate to the dose of the coagulant. The first negative signs were observed after 24h. The study shows that C. hispida is a poor accumulator of aluminium (bioconcentration factor < 200), while bioaccumulation capacity was inhibited at the concentration of approx. 2.0mg Al g-1 d.w. Accumulation in the thalli of the charophytes accounted for 58% of variation following removal of aluminium from the environment. The results of the experiment demonstrate a negative impact of aluminium on charophytes at concentrations used in aggressive restoration of lakes.

GABA(B) receptors play an essential role in maintaining sleep during the second half of the night in Drosophila melanogaster.

GABAergic signalling is important for normal sleep in humans and flies. Here we advance the current understanding of GABAergic modulation of daily sleep patterns by focusing on the role of slow metabotropic GABAB receptors in the fruit fly Drosophila melanogaster. We asked whether GABAB-R2 receptors are regulatory elements in sleep regulation in addition to the already identified fast ionotropic Rdl GABAA receptors. By immunocytochemical and reporter-based techniques we show that the pigment dispersing factor (PDF)-positive ventrolateral clock neurons (LNv) express GABAB-R2 receptors. Downregulation of GABAB-R2 receptors in the large PDF neurons (l-LNv) by RNAi reduced sleep maintenance in the second half of the night, whereas sleep latency at the beginning of the night that was previously shown to depend on ionotropic Rdl GABAA receptors remained unaltered. Our results confirm the role of the l-LNv neurons as an important part of the sleep circuit in D. melanogaster and also identify the GABAB-R2 receptors as the thus far missing component in GABA-signalling that is essential for sleep maintenance. Despite the significant effects on sleep, we did not observe any changes in circadian behaviour in flies with downregulated GABAB-R2 receptors, indicating that the regulation of sleep maintenance via l-LNv neurons is independent of their function in the circadian clock circuit.

Myoinhibitory peptide (MIP) immunoreactivity in the visual system of the blowfly Calliphora vomitoria in relation to putative clock neurons and serotonergic neurons.

A few types of peptidergic clock neurons have been identified in the fruitfly Drosophila, whereas in blowflies, only pigment-dispersing factor (PDF)-immunoreactive lateral ventral clock neurons (LN(v)s) have been described. In blowflies, but not Drosophila, a subset of these PDF-expressing neurons supplies axon branches to a region outside the synaptic layer of the lamina, the most peripheral optic lobe neuropil. In Drosophila, similar lamina processes are instead supplied by non-clock neurons (LMIo) that express myoinhibitory peptide (MIP). We have investigated the distribution of MIP-immunoreactive neurons in the visual system of the blowfly Calliphora vomitoria and found neurons resembling the three LMIos, but without processes to the lamina. In Calliphora, PDF-immunoreactive processes of LN(v)s in the lamina closely impinge on branching serotonin-immunoreactive axon terminations in the same region. We have also identified, in the blowfly, two types of putative clock neurons that label with an antiserum to ion-transport peptide (ITP). The presence of serotonin-immunoreactive neurons supplying processes to the lamina seems to be a conserved feature in dipteran flies. The morphology of the two types of ITP-immunoreactive clock neurons might also be conserved. However, peptidergic neurons with branches converging on the serotonin-immunoreactive neurons in the lamina are of different morphological types and express PDF in blowflies and MIP in Drosophila. The central circuitry of these PDF- and MIP-expressing neurons probably differs; consequently, whether their convergence on serotonergic neurons subserves similar functions in the two species is unclear.