Antimicrobial photodynamic therapy with Brazilian green propolis controls intradermal infection induced by methicillin-resistant Staphylococcus aureus and modulates the inflammatory response in a murine model.

Methicillin-resistant Staphylococcus aureus (MRSA) is one of the leading causes of skin and soft tissue infections worldwide. This microorganism has a wide range of antibiotics resistance, a fact that has made the treatment of infections caused by MRSA difficult. In this sense, antimicrobial photodynamic therapy (aPDT) with natural products has emerged as a good alternative in combating infections caused by antibiotic-resistant microorganisms. The objective of the present study was to evaluate the effects of aPDT with Brazilian green propolis against intradermal MRSA infection in a murine model. Initially, 24 Balb/c mice were infected intradermally in the ears with 1.5 × 108 colony-forming units of MRSA 43300. After infection, they were separated into 4 groups (6 animals per group) and treated with the vehicle, only Brazilian green propolis, only blue LED light or with the aPDT protocol (Brazilian green propolis + blue LED light). It was observed in this study that aPDT with Brazilian green propolis reduced the bacterial load at the site of infection. Furthermore, it was able to inhibit weight loss resulting from the infection, as well as modulate the inflammatory response through greater recruitment of polymorphonuclear cells/neutrophils to the infected tissue. Finally, aPDT induced an increase in the cytokines IL-17A and IL-12p70 in the draining retromaxillary lymph node. Thus, aPDT with Brazilian green propolis proved to be effective against intradermal MRSA infection in mice, reducing bacterial load and modulating the immune response in the animals. However, more studies are needed to assess whether such effects are repeated in humans.

Diabetes and hypertension in elderly women: interactions between severity and failure to control inflammation.

Elderly women are more susceptible to the development of chronic non-communicable diseases. Among these, diabetes mellitus (DM) and systemic arterial hypertension (SAH) stand out. This work aimed to carry out an expanded study on the interactions of anthropometric, biochemical and inflammatory parameters associated with the risk of severity in elderly women with hypertension and diabetes. The study involved the evaluation of 126 elderly women with hypertension and diabetes mellitus. The women were divided according disease severity (low, moderate, high and very high). Anthropometric data were collected by bioimpedance analysis. The inflammatory and biochemical data were obtained from volunteer blood samples. Waist circumference, waist circumference/height ratio, and systolic and diastolic pressures increased with severity. Biochemical marker levels increased with risk of severity, except HDLc. In the very high risk group, there was a higher IL-1ß, IFN-γ and TNF-α production, however, lower IL-10 levels were observed. The very high risk group showed change values for the IL-10/IL-1ß, IL-10/IL-17 and IL-10/TNF-α ratios. The results showed to be extensively altered in the very high risk group, where the inflammatory profile loses its responsiveness. This is the first study that shows an expanded view of the different parameters evaluated in elderly women with hypertension and diabetes.

Relationship among thermal environment, stage of lactation, body characteristics, yield and milk constituents of dairy Gyr cows managed on pasture.

Our aims were to evaluate changes in body characteristics, milk yield and milk constituents as well as to determine the relationship between the thermal environment and production characteristics during the first lactation of dairy Gyr cows managed on pasture. Between 2013 and 2015, forty-five primiparous dairy Gyr cows were evaluated from prepartum to 10 months of lactation in Southeast of Brazil. Body weight, body condition score (BCS), subcutaneous fat thickness (SFT), milk yield (305 d), and milk constituents were collected monthly and progesterone was collected weekly. Additionally, we determined the temperature humidity index (THI) based on microclimate data. Overall, the cows lost body weight until six months of lactation and there was a progressive decrease in BCS, SFT, milk yield and milk lactose as the months in lactation progressed. In contrast, there was an increase in milk fat, milk protein and milk solids. The thermal environment did not pose a consistent heat challenge, nevertheless, we found a positive correlation between the average THI two days before milk collection with milk yield, fat and lactose contents, but in contrast a negative correlation was found with total solids and protein. In conclusion, the THI and months of lactation affected the yield and constituents of milk. However, more studies are necessary to understand the impacts of body characteristics and thermal environment on yield and milk constituents throughout the productive life of Gyr dairy cows.

Characterization of Brazilian green propolis as a photosensitizer for LED light-induced antimicrobial photodynamic therapy (aPDT) against methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin-intermediate Staphylococcus aureus (VISA).

Staphylococcus aureus is the primary cause of skin and soft tissue infections. Its significant adaptability and the development of resistance are the main factors linked to its spread and the challenges in its treatment. Antimicrobial photodynamic therapy emerges as a promising alternative. This work aimed to characterize the antimicrobial photodynamic activity of Brazilian green propolis, along with the key bioactive compounds associated with this activity. Initially, a scanning spectrometry was conducted to assess the wavelengths with the potential to activate green propolis. Subsequently, reference strains of methicillin-resistant Staphylococcus aureus (MRSA ATCC 43300) and vancomycin-intermediate Staphylococcus aureus (VISA ATCC 700699) were exposed to varying concentrations of green propolis: 1 µg/mL, 5 µg/mL, 10 µg/mL, 50 µg /mL and 100 µg/mL and were stimulated by blue, green or red LED light. Finally, high-performance liquid chromatography coupled with a diode array detector and tandem mass spectrometry techniques, along with classic molecular networking analysis, was performed to identify potential bioactive molecules with photodynamic activity. Brazilian green propolis exhibits a pronounced absorption peak and heightened photo-responsiveness when exposed to blue light within the range of 400 nm and 450 nm. This characteristic reveals noteworthy significant photodynamic activity against MRSA and VISA at concentrations from 5 µg/mL. Furthermore, the propolis comprises compounds like curcumin and other flavonoids sourced from flavone, which possess the potential for photodynamic activity and other antimicrobial functions. Consequently, Brazilian green propolis holds promise as an excellent bactericidal agent, displaying a synergistic antibacterial property enhanced by light-induced photodynamic effects.

Hormone therapy in women with premature ovarian insufficiency: a systematic review and meta-analysis.

The aim of this systematic review and meta-analysis was to evaluate the effectiveness of different hormone therapies, including hormonal contraceptives, in women with premature ovarian insufficiency (POI). Thirty reports of 28 studies were included, with a total of 4004 participants with POI from diverse aetiologies, of whom 3785 received hormone therapies and 219 received calcium supplementation, vitamin D, placebo or no treatment. Hormone therapy was superior to non-treatment, placebo, calcitriol or calcium in preserving bone mineral density (BMD) in women with POI. Hormone therapy was associated with up to 80% reduction in the prevalence of hot flushes and with stability or improvement in the quality of life scores. Hormone therapy induced significant increases in uterine volume and endometrial thickness in women with POI. The studies yielded convergent results and were of good quality, although some lacked blinding or had incomplete outcome data. Moderate to high quality evidence was found that hormone therapy with oestrogen and progesterone or progestin (including contraceptives) is beneficial to women with POI, not only to mitigate hypoestrogenic symptoms but also to preserve BMD and avoid uterine atrophy. More studies are needed to confirm the long-term safety of this therapy and to assess its possible impact on the risk of hard outcomes such as bone fractures and cardiovascular events.

DNA Metabarcoding from Microbial Communities Recovered from Stream and Its Potential for Bioremediation Processes.

Urban waste (UW) has caused a series of problems regarding its management. UW comprises domestic, hospital and industrial residues, which makes the destination of this waste a matter of concern, as it may contain a variety of highly toxic environmental polluters. Deactivated dumps can represent sources of contamination of the environment that surround these deposits, harming rivers and inhabiting organisms. Knowledge of the microbial profile of water bodies that can be affected by these toxic residues is essential for the development of alternatives and improvements in treatments applied in rivers and streams. In this sense, this work aimed to analyze the microbial community present in sediments of the Arroio Dourado stream in the municipality of Foz do Iguaçu, a stream located near a deactivated open-air dump. 16S rDNA metabarcoding suggested the dominance of acidogenic bacteria belonging to Acidobacteriota phylum, followed by less abundant phyla Actinobacteriota, Myxococcota, Chloroflexi and a small community of sulfate reducers (Desulfobacteriota). However, more than 50% of amplicon sequence variants (ASVs) were not taxonomically classified. In addition, an expressive abundance was attributed to the genus Anaeromyxobacter, a metabolically versatile group, which can thrive in the presence of polluting compounds present in the deactivated landfill. Thus, a possible stream treatment process can be developed. In addition, culture media can be developed for the recovery of taxonomic groups identified involved in the biodegradation of organic compounds. The results presented expand the knowledge of bacterial diversity in sediment samples recovered from the Arroio Dourado stream.

Physical activity reduces intradermal bacterial load in a murine model submitted to forced swim training - a pilot study.

Regular exercise is beneficial to health. This study evaluated the effects of moderate and intense physical exercise modalities on intradermal infection by Staphylococcus aureus in a murine model. Mice that practiced moderate exercise had lower bacterial load on lymph nodes and less inflammatory infiltrate in dermis. They presented greater weight, however, less amount of epididymal fat: the weight was increased while they had fat diminished. A positive correlation was observed between lipid content and bacterial load in mice trained at moderate intensity. Animals that were under high intensity exercises presented superior bacterial load on the lymph nodes, increased neutrophil count and circulating lymphocytes, and had leukocyte recruitment to the dermis augmented, when compared to the ones in moderate exercise. These findings suggest that moderate physical activity modulates the immune response in dermal infection caused by S. aureus in a murine model.

Gender-related differences in the modulation of anthropometric, biochemical, and immune markers by physical activity in hypertensive and diabetic individuals.

Systemic arterial hypertension (SAH) and type 2 diabetes mellitus (T2DM) compose the two major noncommunicable chronic inflammatory diseases. Physical activity has been shown as a promising complementary approach to control the systemic inflammation. However, it is still unclear whether this modulation is gender-dependent. The objective of this study was evaluate the gender-related influence of physical activity on the inflammatory response and biochemical profile of individuals with SAH and T2DM. An international physical activity questionnaire was applied to 376 individuals diagnosed with SAH and T2DM in order to access their exercises routine and was evaluated the influence of physical activity in biochemical, anthropometrical, and immunological markers involved in these disorders in men and women. Even though active individuals have exhibited lower serum levels of IL-1ß, IFN-γ, TNF-α, and IL-17A, the ratios between IL-10 and all inflammatory cytokines were higher in men than in women. Physically active individuals also demonstrated increased HDL/LDL and HDL/VLDL ratios. Moreover, multiple correlations revealed that in active women both IL-10 and TNF-α serum levels positively correlate with fasting glucose levels, and were negatively associated with HDL levels. Our findings suggest that gender-related differences dictate a distinct crosstalk between inflammatory and biochemical markers in physically active individuals.

Evaluation of transfer learning of pre-trained CNNs applied to breast cancer detection on infrared images.

Breast cancer accounts for the highest number of female deaths worldwide. Early detection of the disease is essential to increase the chances of treatment and cure of patients. Infrared thermography has emerged as a promising technique for diagnosis of the disease due to its low cost and that it does not emit harmful radiation, and it gives good results when applied in young women. This work uses convolutional neural networks in a database of 440 infrared images of 88 patients, classifying them into two classes: normal and pathology. During the training of the networks, we use transfer learning of the following convolutional neural network architectures: AlexNet, GoogLeNet, ResNet-18, VGG-16, and VGG-19. Our results show the great potential of using deep learning techniques combined with infrared images in the aid of breast cancer diagnosis.

Effects of 3-Heptyl-3,4,6-trimethoxy-3H-isobenzofuran-1-one alone or/in association with cyclophosphamide on testicular function.

Chemotherapy for cancer treatment may result in a temporary or long-term gonadal damage resulting in subfertility or infertility. Cyclophosphamide (CY) is a cytotoxic alkylating agent that has been widely used in the treatment of cancer. Recent studies have shown that synthetic resorcinol lipid AMS35AA (3-Heptyl-3,4,6-trimethoxy-3H-isobenzofuran-1-one) may be an important adjuvant chemotherapy that potentiates mutagenic damage and increases apoptosis caused by CY. The present study investigates the action of AMS35AA alone or/in association with CY on testicular function. Animals were divided into four groups: (a) control group: received only water; (b) CY group: received 150 µg/g of CY b.w., i.p.; (c) AMS35AA group: received 10 µg/g of AMS35AA b.w., i.p; and (d) associated group: received 10 µg/g of AMS35AA + 150 µg/g of CY b.w., i.p. Four weeks after the treatment, the results showed that testes weight of CY and associated groups decreased. However, the number of Sertoli cell and Leydig cell per testis was similar in control and treated groups. Our findings provide strong evidence that the AMS35AA alone or in CY association is not toxic to spermatogenesis. The absence of toxicity of AMS35AA supports the view that the resorcinolic lipid could be used associated with CY chemotherapy without causing adverse effects to testes function.

Surveillance of donated blood during the 2016 arbovirus outbreak in Brazil.

Reports of arboviral transmission via blood transfusion may be a cause of concern among asymptomatic infected donors. This study evaluated the presence of arboviruses in donated blood products during the 2016 outbreak in Vitória da Conquista (Bahia-Brazil). Serum samples (n = 676) were screened for ZIKV, CHIKV, and the four DENV serotypes using a one-step reverse transcriptase-based Real-Time Polymerase Chain Reaction (RT-PCR). No samples tested positive for any of the targets, whereas positive controls performed as expected. The results suggest a low risk of arboviral transmission via transfusion of blood products in the endemic area studied during the 2016 outbreak.

Single electron reduction of NHC-CO2-borane compounds.

The carbon dioxide radical anion [CO2˙-] is a highly reactive species of fundamental and synthetic interest. However, the direct one-electron reduction of CO2 to generate [CO2˙-] occurs at very negative reduction potentials, which is often a limiting factor for applications. Here, we show that NHC-CO2-BR3 species - generated from the Frustrated Lewis Pair (FLP)-type activation of CO2 by N-heterocyclic carbenes (NHCs) and boranes (BR3) - undergo single electron reduction at a less negative potential than free CO2. A net gain of more than one volt was notably measured with a CAAC-CO2-B(C6F5)3 adduct, which was chemically reduced to afford [CAAC-CO2-B(C6F5)3˙-]. This room temperature stable radical anion was characterized by EPR spectroscopy and by single-crystal X-ray diffraction analysis. Of particular interest, DFT calculations showed that, thanks to the electron withdrawing properties of the Lewis acid, significant unpaired spin density is localised on the carbon atom of the CO2 moiety. Finally, these species were shown to exhibit analogous reactivity to the carbon dioxide radical anion [CO2˙-] toward DMPO. This work demonstrates the advantage provided by FLP systems in the generation and stabilization of [CO2˙-]-like species.

Safety, Efficacy, and Immunogenicity of Therapeutic Vaccines for Patients with High-Grade Cervical Intraepithelial Neoplasia (CIN 2/3) Associated with Human Papillomavirus: A Systematic Review.

Despite the knowledge that HPV is responsible for high-grade CIN and cervical cancer, little is known about the use of therapeutic vaccines as a treatment. We aimed to synthesize and critically evaluate the evidence from clinical trials on the safety, efficacy, and immunogenicity of therapeutic vaccines in the treatment of patients with high-grade CIN associated with HPV. A systematic review of clinical trials adhering to the PRISMA 2020 statement in MEDLINE/PubMed, Embase, CENTRAL Cochrane, Web of Science, Scopus, and LILACS was undertaken, with no data or language restrictions. Primary endpoints related to the safety, efficacy, and immunogenicity of these vaccines were assessed by reviewing the adverse/toxic effects associated with the therapeutic vaccine administration via histopathological regression of the lesion and/or regression of the lesion size and via viral clearance and through the immunological response of individuals who received treatment compared to those who did not or before and after receiving the vaccine, respectively. A total of 1184 studies were identified, and 16 met all the criteria. Overall, the therapeutic vaccines were heterogeneous regarding their formulation, dose, intervention protocol, and routes of administration, making a meta-analysis unfeasible. In most studies (n = 15), the vaccines were safe and well tolerated, with clinical efficacy regarding the lesions and histopathological regression or viral clearance. In addition, eleven studies showed favorable immunological responses against HPV, and seven studies showed a positive correlation between immunogenicity and the clinical response, indicating promising results that should be further investigated. In summary, therapeutic vaccines, although urgently needed to avoid progression of CIN 2/3 patients, still present sparse data, requiring greater investments in a well-designed phase III RCT.

Additional vinyl ketones and their pyranyl ketones in gonyleptid harvestmen (Arachnida: Opiliones) suggest these metabolites are widespread in this family.

Four species of gonyleptid harvestmen, Acanthogonyleptes pulcher, Gonyleptes saprophilus (Gonyleptinae), Sodreana barbiellini, and Sodreana leprevosti (Sodreaninae), were examined by GC-MS and ¹³H NMR. All of these species release vinyl ketones, and three of them produce the corresponding pyranyl ketones, which are presumed hetero-Diels-Alder (HDA) dimers. The vinyl ketones 5-methyl-1-hexen-3-one, rac-4-methyl-1-hexen-3-one, and (S)-4-methyl-1-hexen-3-one were synthesized. Natural 4-methyl-1-hexen-3-one is present as a single stereoisomer and has the R-configuration. Vinyl ketone dimers (HDA dimers) were also observed in the scent gland exudate and characterized by HRMS, ¹³C NMR, and ¹H NMR chemical shifts of the pyranyl moiety.

Hilab System Device in an Oncological Hospital: A New Clinical Approach for Point of Care CBC Test, Supported by the Internet of Things and Machine Learning.

The complete blood count (CBC) is a highly requested test that is generally restricted to centralized laboratories, which are limited by high cost, being maintenance-demanding, and requiring costly equipment. The Hilab System (HS) is a small, handheld hematological platform that uses microscopy and chromatography techniques, combined with machine learning (ML) and artificial intelligence (AI), to perform a CBC test. This platform uses ML and AI techniques to add higher accuracy and reliability to the results besides allowing for faster reporting. For clinical and flagging capability evaluation of the handheld device, the study analyzed 550 blood samples of patients from a reference institution for oncological diseases. The clinical analysis encompassed the data comparison between the Hilab System and a conventional hematological analyzer (Sysmex XE-2100) for all CBC analytes. The flagging capability study compared the microscopic findings from the Hilab System and the standard blood smear evaluation method. The study also assessed the sample collection source (venous or capillary) influences. The Pearson correlation, Student t-test, Bland-Altman, and Passing-Bablok plot of analytes were calculated and are shown. Data from both methodologies were similar (p > 0.05; r ≥ 0.9 for most parameters) for all CBC analytes and flagging parameters. Venous and capillary samples did not differ statistically (p > 0.05). The study indicates that the Hilab System provides humanized blood collection associated with fast and accurate data, essential features for patient wellbeing and quick physician decision making.

CNN architecture optimization using bio-inspired algorithms for breast cancer detection in infrared images.

The early detection of breast cancer is a vital factor when it comes to improving cure and recovery rates in patients. Among such early detection factors, one finds thermography, an imaging technique that demonstrates good potential as an early detection method. Convolutional neural networks (CNNs) are widely used in image classification tasks, but finding good hyperparameters and architectures for these is not a simple task. In this study, we use two bio-inspired optimization techniques, genetic algorithm and particle swarm optimization to find good hyperparameters and architectures for the fully connected layers of three state of the art CNNs: VGG-16, ResNet-50 and DenseNet-201. Through use of optimization techniques, we obtained F1-score results above 0.90 for all three networks, an improvement from 0.66 of the F1-score to 0.92 of the F1-score for the VGG-16. Moreover, we were also able to improve the ResNet-50 from 0.83 of the F1-score to 0.90 of the F1-score for the test data, when compared to previously published studies.

Medicines as an emergent contaminant: the review of microbial biodegration potential.

Emerging environmental contaminants, such as medicine waste, are of great concern to the scientific community and to the local environmental and health departments because of their potential long-term effects and ecotoxicological risk. Besides the prolonged use of medicines for the development of modern society, the elucidation of their effect on the ecosystem is relatively recent. Medicine waste and its metabolites can, for instance, cause alterations in microbial dynamics and disturb fish behavior. Bioremediation is an efficient and eco-friendly technology that appears as a suitable alternative to conventional methods of water waste and sludge treatment and has the capacity to remove or reduce the presence of emerging contaminants. Thus, this review has the objective of compiling information on environmental contamination by common medicines and their microbial biodegradation, focusing on five therapeutic classes: analgesics, antibiotics, antidepressants, non-steroidal anti-inflammatory drugs (NSAIDs), and contraceptives. Their effects in the environment will also be analyzed, as well as the possible routes of degradation by microorganisms.

Inflammaging and body composition: New insights in diabetic and hypertensive elderly men.

Age-related changes in the body's physiological responses play a critical role in systemic arterial hypertension (SAH) and type 2 Diabetes mellitus (T2DM). SAH and T2DM have clinically silent low-grade inflammation as a common risk factor. This inflammation has a relevant element, the excess of fatty tissue. In this scenario, little is known about how inflammatory markers interact with each other. Therefore, this work evaluated the interplay among anthropometric, biochemical, and inflammatory markers in the elderly with SAH and T2DM. Men aged 60-80 years old with SAH and T2DM were classified by body mass index (BMI) as eutrophic elderly (EE, 24 individuals) or overweight elderly (OE, 25 individuals). Body composition analysis was performed using bioimpedance. Blood samples were collected to perform inflammatory and biochemical evaluations. The cytokines IL-17A, IL-1ß, IFN-y, TNF-α, and IL-10, were evaluated by ELISA. Triglycerides, total and fractions of cholesterol, and glucose were measured by spectrophotometry. Overweight elderly men had a higher glycemic index and an increase in most anthropometric markers, as well as higher means for all pro-inflammatory cytokines analyzed (IL-17A, IL-1ß, IFN-y, and TNF-α) in comparison to their eutrophic elderly counterparts. However, there was a decrease in IL-10 anti-inflammatory cytokine and IL-10/IL-17A ratio compared to their eutrophic elderly counterparts. Although overweight elderly men have worsening inflammatory parameters, the magnitude of their correlations with anthropometric and biochemical parameters becomes less evident. The Bayesian networks highlight that in the eutrophic elderly, IL-17A and TNF-α are the cytokines most associated with interactions, and most of these interactions occur with biochemical parameters. It is worth highlighting the role of IFN-y in overweight elderly men. This cytokine influences IL-10 and TNF-α production, contributing to the inflammatory profile exacerbated in this group.

The sweet fuel of inflammation: New perspectives on the complex web that interconnects diabetes.

Due to the inflammatory nature of type 2 diabetes mellitus (T2DM) and the increased cardiovascular risk, there is a growing need for innovative strategies to change our identification and treatment approach to avoid clinical complications. One approach would be the use of circulating biomarkers to track disease progression and management. Thus, this study aimed to evaluate the concentrations of inflammatory biomarkers in patients diagnosed with type 2 diabetes mellitus and systemic arterial hypertension, correlating inflammatory cytokines and disease severity. Initially, 259 individuals were stratified into different degrees of disease: low risk, moderate risk, high risk, and very high risk, according to the European Society of Cardiology, which correlates blood pressure values with the presence of cardiovascular risk factors. For this stratification, analysis of body composition, blood pressure measurement, and questionnaires were applied. Blood was collected for biochemical measurements and for ELISA to detect concentrations of cytokines IL-17, IL-1ß, IFN-Y, TNF-α, and IL-10. The findings suggest that inflammation is present, contributing to the worsening of systemic arterial hypertension and type 2 diabetes mellitus. Through Bayesian analysis, we found that hyperglycemia plays a role in fueling inflammation, contributing to the maintenance of the state of dysregulation and persistent inflammation, which can contribute to systemic damage. Our work correlates biochemical, glycemic, body composition, blood pressure and inflammatory profiles, showing how they participate together in worsening the prognosis of patients diagnosed with chronic non-communicable diseases. We have seen that all these parameters can be changed with the practice of physical activity, even in conditions of obesity, hyperglycemia or dyslipidemia, when patients do not control the changes with standard pharmacological treatment. Thus, the management measures of these chronic non-communicable diseases must take into account the crosstalk between the systems, and the dysregulation of just one of these systems is enough to generate consequences in all the other systems.

6-Alkyl-3,4-dihydro-2H-pyrans: chemical secretion compounds in neotropical harvestmen.

The defensive secretions of five neotropical species of harvestmen (Opiliones: Gonyleptidae) from the Brazilian Atlantic Forest were analyzed and chemically characterized by GC-MS and NMR methods. Three of the species, Cobania picea, Roweria virescens, and Serracutisoma proximum, secrete a mixture of 2,3-dimethyl-1,4-benzoquinone and 2-ethyl-3-methyl-1,4-benzoquinone. The secretions produced by the other two species, Iporangaia pustulosa and Neosadocus maximus, contain 1-hepten-3-one, 5-methyl-1-hexen-3-one, and 1-(6-butyl-3,4-dihydro-2H-pyran-2-yl)pentanone (1) as major components, as well as 2,3-dimethyl-1,4-benzoquinone and 2-ethyl-3-methyl-1,4-benzoquinone as minor constituents. The dihydropyran 1-(6-butyl-3,4-dihydro-2H-pyran-2-yl)pentanone (1) is a new natural product, composed of two 1-hepten-3-one subunits formally linked in a hetero-Diels-Alder reaction. The natural product was proven to be racemic, and its biogenetic origin is discussed.