Can a Sacrococcygeal Epidural of 0.25% Bupivacaine Prevent the Activation of the Sympathetic Nervous System during Feline Ovariectomy?

The ovariectomy (OVE) procedure can trigger somatosensory and visceral peritoneal nociception. Sacrococcygeal epidural (ScE) anesthesia may complement or replace systemic analgesia used for feline OVE, reducing opioid consumption and their related undesirable adverse effects and consequently reducing or completely blocking the sympathetic nervous system activation during this procedure. The present study aimed to evaluate the activation of the sympathetic nervous system resulting from adding an ScE injection of bupivacaine 0.25% (0.3 mL kg-1) in feline OVE and identify whether this translates to hemodynamic variables stability. A Parasympathetic Tone Activity (PTA) monitor was applied given that it performs analysis of heart rate variability (HRV) detecting changes in sympathetic and parasympathetic tone, making it a good tool for detecting activation of the sympathetic nervous system during the study. Two groups of animals were evaluated in five perioperative times, namely, the control group (CG) (n = 18) with systemic analgesia alone and the sacrococcygeal epidural group (ScEG) (n = 20) with 0.25% bupivacaine combined with systemic analgesia. Thirty-eight female cats were selected. All animals assigned to CG and ScEG were premedicated with dexmedetomidine (20 µg kg-1 IM) and methadone (0.2 mg kg-1 IM). General anesthesia was induced with propofol IV ad effectum and maintained with isoflurane in 100% oxygen. Heart rate, non-invasive systolic and median blood pressure, respiratory rate, and instantaneous parasympathetic tone activity were recorded. Compared to systemic analgesia alone (CG), sacrococcygeal epidural (ScEG) reduced the rise of common hemodynamic variables but did not prevent sympathetic nervous system activation.

Explainable artificial intelligence (xAI) in neuromarketing/consumer neuroscience: an fMRI study on brand perception.

Introduction: The research in consumer neuroscience has identified computational methods, particularly artificial intelligence (AI) and machine learning, as a significant frontier for advancement. Previously, we utilized functional magnetic resonance imaging (fMRI) and artificial neural networks (ANNs) to model brain processes related to brand preferences in a paradigm exempted from motor actions. In the current study, we revisit this data, introducing recent advancements in explainable artificial intelligence (xAI) to gain insights into this domain. By integrating fMRI data analysis, machine learning, and xAI, our study aims to search for functional brain networks that support brand perception and, ultimately, search for brain networks that disentangle between preferred and indifferent brands, focusing on the early processing stages. Methods: We applied independent component analysis (ICA) to overcome the expected fMRI data's high dimensionality, which raises hurdles in AI applications. We extracted pertinent features from the returned ICs. An ANN is then trained on this data, followed by pruning and retraining processes. We then apply explanation techniques, based on path-weights and Shapley values, to make the network more transparent, explainable, and interpretable, and to obtain insights into the underlying brain processes. Results: The fully connected ANN model obtained an accuracy of 54.6%, which dropped to 50.4% after pruning. However, the retraining process allowed it to surpass the fully connected network, achieving an accuracy of 55.9%. The path-weights and Shapley-based analysis concludes that, regarding brand perception, the expected initial participation of the primary visual system is followed. Other brain areas participate in early processing and discriminate between preferred and indifferent brands, such as the cuneal and the lateral occipital cortices. Discussion: The most important finding is that a split between processing brands|preferred from brands|indifferent may occur during early processing stages, still in the visual system. However, we found no evidence of a "decision pipeline" that would yield if a brand is preferred or indifferent. The results suggest the existence of a "tagging"-like process in parallel flows in the extrastriate. Network training dynamics aggregate specific processes within the hidden nodes by analyzing the model's hidden layer. This yielded that some nodes contribute to both global brand appraisal and specific brand category classification, shedding light on the neural substrates of decision-making in response to brand stimuli.

The Performance of Using the Parasympathetic Tone Activity (PTA) Index to Assess Intraoperative Nociception in Cats.

BACKGROUND: The monitoring of nociception/antinociception poses a significant challenge during anesthesia, making the incorporation of new tools like the Parasympathetic Tone Activity (PTA) monitor an added value in feline anesthesia. OBJECTIVES: To compare the effectiveness and speed of PTA monitoring when compared to heart rate (HR) in detecting surgical stimuli (SS) during the intraoperative period in 49 female cats undergoing ovariectomy (OV). METHODS: Instantaneous Parasympathetic Tone Activity (PTAi) values, HR, fR, and non-invasive SAP and MAP were continuously monitored and systematically assessed. The time required for HR (HR time) and PTAi (PTAi time) to reach their minimum peak values following each surgical stimulus was collected at five points for each anaesthetized cat. Each collected surgical stimulus was categorized into 3 groups for statistical analysis: no nociception detection, no hemodynamic reaction and a PTAi > 50 (Nhre); no hemodynamic reaction and a PTAi < 50 (Nhre < 50); and hemodynamic reaction and PTAi < 50 (Hre < 50). RESULTS: PTAi response demonstrated effectiveness in detecting nociception compared to HR. The SS were categorized as 36.1% in the Nhre group, 50% in the Nhre < 50 group, and only 13.9% in the Hre < 50 group. In the Hre < 50 group, PTAi time and HR time had similar speeds in detecting the SS (p = 0.821); however, PTA time was significantly slower in the Nhre < 50 group when compared to the Hre < 50 group (p = 0.001). CONCLUSIONS: PTA monitoring may be a useful tool to complement HR monitoring for detecting nociception. PTA monitoring demonstrated a superior diagnostic value compared to HR for detecting nociception in cats undergoing OV and a similar speed to HR in detecting SS when HR increases above 20%. Future studies are needed to understand in a clinical setting the meaning of sympathetic activation/nociception detected using the PTA monitor when the HR increase is not clinically relevant.

Unveiling the bioactive potential of Actinomycetota from the Tagus River estuary.

The increase in global travel and the incorrect and excessive use of antibiotics has led to an unprecedented rise in antibiotic resistance in bacterial and fungal populations. To overcome these problems, novel bioactive natural products must be discovered, which may be found in underexplored environments, such as estuarine habitats. In the present work, estuarine actinomycetotal strains were isolated with conventional and iChip techniques from the Tagus estuary in Alcochete, Portugal, and analysed for different antimicrobial bioactivities. Extracts were produced from the isolated cultures and tested for bioactivity against Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, Aspergillus fumigatus ATCC 240305, Candida albicans ATCC 10231 and Trichophyton rubrum FF5. Furthermore, bioactive extracts were subjected to dereplication by high-performance liquid chromatography (HPLC) and high-resolution mass spectrometry (HRMS) to putatively identify their chemical components. In total, 105 isolates belonging to 3 genera were obtained. One which was isolated, MTZ3.1 T, represents a described novel taxon for which the name Streptomyces meridianus was proposed. Regarding the bioactivity testing, extracts from 12 strains proved to be active against S. aureus, 2 against E. coli, 4 against A. fumigatus, 3 against C. albicans and 10 against T. rubrum. Dereplication of bioactive extracts showed the presence of 28 known bioactive molecules, 35 hits have one or more possible matches in the DNP and 18 undescribed ones. These results showed that the isolated bacteria might be the source of new bioactive natural products.

Comparison between Bilateral Ultrasound-Guided Quadratus Lumborum Block and Sacrococcygeal Epidural in Cats Undergoing Ovariectomy.

BACKGROUND: Ultrasound-guided quadratus lumborum block (QLB) and sacrococcygeal epidural anaesthesia (ScE) have been used for neutering cats, providing effective pain relief. OBJECTIVES: To compare the effects of the QLB with those of ScE in cats undergoing ovariectomies. METHODS: Feral cats undergoing ovariectomy were premedicated with dexmedetomidine (20 µg kg-1) and methadone (0.2 mg kg-1) intramuscularly. Anaesthesia was induced with 2-4 mg kg-1 of propofol intravenously and maintained with isoflurane in oxygen. The cats were randomly allocated to the groups QLB (bilateral QLB with 0.4 mL kg-1 of 0.25% bupivacaine) and ScE (0.3 mL kg-1 of 0.25% bupivacaine). Hemodynamic data and analgesia rescue were collected at four intraoperative periods. The pain scale and motor block were assessed in both groups during the postoperative period. RESULTS: The ScE results in increased hypotension, prolonged extubation time, and higher postoperative motor block than the QLB (p < 0.05). The QLB and ScE groups required a similar number of intraoperative rescues and presented the same postoperative pain scale classification. CONCLUSIONS: The QLB with 0.25% bupivacaine is a potential alternative to ScE with 0.25% bupivacaine in perioperative pain management in elective cat ovariectomy. The QLB promoted less hypotension and postoperative motor block when compared with the ScE group.

iChip-Inspired Isolation, Bioactivities and Dereplication of Actinomycetota from Portuguese Beach Sediments.

Oceans hold a stunning number of unique microorganisms, which remain unstudied by culture-dependent methods due to failures in establishing the right conditions for these organisms to grow. In this work, an isolation effort inspired by the iChip was performed using marine sediments from Memoria beach, Portugal. The isolates obtained were identified by 16S rRNA gene analysis, fingerprinted using BOX-PCR and ERIC-PCR, searched for the putative presence of secondary metabolism genes associated with polyketide synthase I (PKS-I) and non-ribosomal peptide synthetases (NRPS), screened for antimicrobial activity against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 29213, and had bioactive extracts dereplicated by LC/HRMS. Of the 158 isolated strains, 96 were affiliated with the phylum Actinomycetota, PKS-I and NRPS genes were detected in 53 actinomycetotal strains, and 11 proved to be bioactive (10 against E. coli, 1 against S. aureus and 1 against both pathogens). Further bioactivities were explored using an "one strain many compounds" approach, with six strains showing continued bioactivity and one showing a novel one. Extract dereplication showed the presence of several known bioactive molecules and potential novel ones in the bioactive extracts. These results indicate the use of the bacteria isolated here as sources of new bioactive natural products.

Comparison of dorsoventral and ventrodorsal approaches for ultrasound-guided quadratus lumborum block in cats: a cadaver study.

OBJECTIVE: To assess the feasibility of an ultrasound (US)-guided quadratus lumborum (QL)-psoas muscle (Pm) interfascial plane injection using a dorsoventral (DV) approach, and to compare needle visualization and distribution pattern between DV and ventrodorsal (VD) approaches. STUDY DESIGN: Experimental anatomical study. ANIMALS: A total of 14 cat cadavers. METHODS: Bilateral in-plane US-guided injections in the QL-Pm plane were performed at the level of the second lumbar (L2) transverse process. A spinal needle was inserted using either a VD or DV approach. A total volume of 0.4 mL kg-1 of a solution of ropivacaine 0.18%, tissue dye and iohexol (350 mg mL-1), in a proportion of 3:1:1, respectively, was injected bilaterally. Spread of injectate was compared and evaluated using US, computed tomography (CT) scanning and anatomical dissection. Presence of dye on the sympathetic trunk was compared between methods using Kappa (κ) coefficient of agreement. RESULTS: The QL-Pm plane was visualized, and dye was present in the target plane using both approaches. Needle visualization in the VD approach was enhanced compared with the DV approach (p = 0.0005). Mean distribution along the sympathetic trunk was 4.8 and 4.1 segments in the VD and DV approaches, respectively, showing non-statistical differences. The ventral branches of L1, L2 and L3 were successfully stained in 11/14 and 6/14 using the VD and DV approaches, respectively. Substantial agreement (κ = 0.61) of sympathetic trunk staining was observed between CT scan and anatomical dissection. Dye was observed cranial to the diaphragm in 7/8 cases on CT with both approaches. Epidural and abdominal cavity dye distribution was not observed. CONCLUSIONS AND CLINICAL RELEVANCE: The DV approach to the QL-Pm plane could be an alternative to the VD approach. Both approaches seem capable of reaching the spinal nerves, the sympathetic trunk and both splanchnic and coeliac nerves in feline cadavers.

A description of an ultrasound-guided technique for a quadratus lumborum block in the cat: a cadaver study.

OBJECTIVES: To describe the ultrasonographic (US) anatomy of the sublumbar region at the level of second lumbar vertebra (L2), to assess the feasibility of US-guided quadratus lumborum (QL) injections and to evaluate the dye distribution pattern in feline cadavers. STUDY DESIGN: Descriptive feline cadaver study. ANIMALS: A total of eight cat cadavers. METHODS: Using a linear probe (6-14 MHz), with the cadavers in lateral recumbency, the QL and psoas muscles (Pm) were identified at the level of L2 and landmarks recorded. Using an in-plane technique, a spinal needle was inserted in a ventrodorsal direction to reach the interfascial plane between the QL and Pm. Using a ropivacaine, dye and iohexol solution, a total volume of 0.4 mL kg-1 was injected. Computed tomography (CT) scanning and anatomic dissection were performed to evaluate the spread of injectate. Presence of dye on the sympathetic trunk was compared between assessment methods using kappa coefficient of agreement (κ). RESULTS: Using US guidance, the QL-Pm interfascial plane was identified and dye solution was present in the target fascial plane in all animals. Injectate was distributed on the ventral roots of the spinal nerves between the first and third lumbar vertebrae in 6/8 cats, and on the sympathetic trunk from the thirteenth thoracic to the third lumbar vertebrae in 7/8. Dye was found on the major splanchnic nerve in 7/8 cats and on the minor splanchnic nerve and coeliac ganglion pathways in all animals. Agreement between dissection and CT images dye distribution on the sympathetic trunk was κ = 0.72. CONCLUSIONS AND CLINICAL RELEVANCE: The US-guided QL injection was feasible and injectate was present in the QL-Pm interfascial plane in all feline cadavers. In vivo studies are warranted to evaluate the analgesic efficacy of this technique for abdominal surgical procedures.

Relation between periodontal disease and systemic diseases in dogs.

Periodontal disease (PD) is one of the most frequent and widespread inflammatory diseases in dogs. The onset of PD pathogenesis is prompted by the dental microbial biofilm combined with the animal immune-inflammatory response. Along with local effects, systemic consequences can occur secondary to dental plaque-associated bacteraemia, affecting distant tissues and organs. The main goal of this retrospective study was to access and evaluate the association between PD and systemic consequences (renal, hepatic and cardiac) in a group of 136 dogs. Clinical records of all animals were assessed for general and systemic information, further analysed by general linear model and Odds-Ratio. Animals were organized in two groups, PD group and control group, formed by animals without PD. In this population, increasing age was proven to be a risk factor (OR = 1.04, p < .01) for PD establishment. Small breeds (<10 Kg) were the most prevalent in the PD group, being more susceptible to this disease. On the other hand, no influence of gender or reproductive status in PD progression was observed. Regarding systemic diseases, a statistically significant association (p = .026) was obtained between PD and cardiac disease. Results show that PD can have a significant adverse impact on animals' health, being related with systemic consequences, which may increase morbidity and mortality rates of these animals. PD prevention, with focus on owner's information about this disease and its management, are essential points for an active PD control program.