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Veterinary Anaesthesia and Analgesia Jun 2024To evaluate the effect of body position on transesophageal atrial pacing (TEAP) in dogs.
OBJECTIVE
To evaluate the effect of body position on transesophageal atrial pacing (TEAP) in dogs.
STUDY DESIGN
Prospective, experimental trial.
ANIMALS
A total of eight mixed-breed dogs, median body mass 25 kg (range 11-31 kg).
METHODS
TEAP was performed using a 6 Fr (2 mm) pacing catheter introduced transorally and positioned in the lower esophagus in left lateral recumbency. The catheter was withdrawn in 5 mm increments until successful TEAP. The minimum pacing threshold (MPT) was determined at each 5 mm increment until atrial capture could not be achieved at a maximal pulse amplitude of 40 mA. The zone of capture (ZOC) was the total distance over which TEAP was achieved. The same process was repeated in right lateral, ventral and dorsal recumbency. A linear mixed model was used to assess the impact of body position on TEAP and ZOC.
RESULTS
TEAP was achieved in all body positions. There was significant random effect of individual dogs on ZOC (p = 0.048) but not on MPT (p = 0.109). MPT was 11.56 ± 8.65 mA (mean ± SD), 8.43 ± 2.29 mA, 10.63 ± 6.91 mA and 10 ± 7.44 mA for dorsal, left and right lateral, and ventral recumbency, respectively. ZOC was 5.12 ± 2.08 cm, 6.35 ± 2.41 cm, 5.94 ± 3.23 cm and 5.31 ± 2.2 cm for dorsal, left lateral and right lateral, and ventral recumbency, respectively. Neither ZOC (p = 0.363) nor MPT (p = 0.716) varied significantly between body positions.
CONCLUSIONS AND CLINICAL RELEVANCE
TEAP can be performed successfully in all body positions in dogs. Body position did not significantly influence MPT or ZOC values for TEAP. Further studies are needed to compare the efficacy of TEAP with the efficacy of standard pharmacological therapy for management of bradycardia during general anesthesia in dogs.
PubMed: 38926065
DOI: 10.1016/j.vaa.2024.06.001 -
BMJ Case Reports Jun 2024Large ventral hernias require complex surgical techniques, such as component separation. We are presenting a case of an incisional hernia measuring 15×8 cm. The...
Large ventral hernias require complex surgical techniques, such as component separation. We are presenting a case of an incisional hernia measuring 15×8 cm. The hernia was covered with an overlying thin layer of skin and hernia sac. The skin of this layer was densely adherent to the underlying hernial sac. Because of the thin hernial sac and adherent nature of the skin, approximately 3 cm of the hernial sac was preserved. We used this hernial sac as the anterior sheath 'extension' for a tension-free closure. Posterior component separation with transverse abdominis muscle release was done to close the posterior layer without tension and to place a 23×16 cm mesh in the retrorectus plane. By using the hernial sac in repair, we avoided anterior component separation and achieved tension-free closure of the anterior layer.
Topics: Humans; Hernia, Ventral; Incisional Hernia; Herniorrhaphy; Surgical Mesh; Female; Male; Middle Aged
PubMed: 38925674
DOI: 10.1136/bcr-2024-261046 -
Urology Jun 2024To analyze current standards in urethroplasty by urologists employing buccal mucosal grafts (BMG) for treating urethral stricture disease (USD).
OBJECTIVES
To analyze current standards in urethroplasty by urologists employing buccal mucosal grafts (BMG) for treating urethral stricture disease (USD).
METHODS
An IRB-approved online survey was distributed to members of the Society of Genitourinary Reconstructive Surgeons (GURS) between July and October 2022 to assess BMG utilization in urethroplasty. Questions covered surgeon experience, graft harvest site, graft length, surgical technique, and perceived success rates.
RESULTS
Of 350 invited GURS members, 134 responded (38%). 69% were GURS fellowship-trained, performing 10-30 urethroplasties annually. 95% harvested their own grafts, with 99% preferring buccal mucosa as the primary site. Buccal mucosa was favored over fasciocutaneous flap for penile urethroplasty, regardless of circumcision status (95% with, 84% without). For bulbar urethroplasty with BMG, dorsal graft placement was favored (66%) over ventral (34%). Most surgeons (90%) preferred multiple BMGs over combined graft/flap for panurethral strictures. When harvesting long grafts, 56% preferred using both cheeks. Anastomotic urethroplasty was preferred over buccal graft urethroplasty for short bulbomembranous stenosis post-radiotherapy (63% vs. 37%). Surgeons reported a success rate of 80-90% (53%).
CONCLUSIONS
The expanded scope of reconstructive urology has led to increased use of BMG in diverse urethral reconstructions. Buccal grafts are now preferred for penile, bulbar, and panurethral strictures, demonstrating high perceived success rates in the reconstructive community.
PubMed: 38925372
DOI: 10.1016/j.urology.2024.06.019 -
Current Biology : CB Jun 2024Environmental cues, through Pavlovian learning, become conditioned stimuli that invigorate and guide animals toward rewards. Dopamine (DA) neurons in the ventral...
Environmental cues, through Pavlovian learning, become conditioned stimuli that invigorate and guide animals toward rewards. Dopamine (DA) neurons in the ventral tegmental area (VTA) and substantia nigra (SNc) are crucial for this process, via engagement of a reciprocally connected network with their striatal targets. Critically, it remains unknown how dopamine neuron activity itself engages dopamine signals throughout the striatum, across learning. Here, we investigated how optogenetic Pavlovian cue conditioning of VTA or SNc dopamine neurons directs cue-evoked behavior and shapes subregion-specific striatal dopamine dynamics. We used a fluorescent biosensor to monitor dopamine in the nucleus accumbens (NAc) core and shell, dorsomedial striatum (DMS), and dorsolateral striatum (DLS). We demonstrate spatially heterogeneous, learning-dependent dopamine changes across striatal regions. Although VTA stimulation-evoked robust dopamine release in NAc core, shell, and DMS, predictive cues preferentially recruited dopamine release in NAc core, starting early in training, and DMS, late in training. Negative prediction error signals, reflecting a violation in the expectation of dopamine neuron activation, only emerged in the NAc core and DMS. Despite the development of vigorous movement late in training, conditioned dopamine signals did not emerge in the DLS, even during Pavlovian conditioning with SNc dopamine neuron activation, which elicited robust DLS dopamine release. Together, our studies show a broad dissociation in the fundamental prediction and reward-related information generated by VTA and SNc dopamine neuron populations and signaled by dopamine across the striatum. Further, they offer new insight into how larger-scale adaptations across the striatal network emerge during learning to coordinate behavior.
PubMed: 38925117
DOI: 10.1016/j.cub.2024.05.069 -
Journal of Neural Engineering Jun 2024Speech brain-computer interfaces (BCIs) have the potential to augment communication in individuals with impaired speech due to muscle weakness, for example in ALS and...
OBJECTIVE
Speech brain-computer interfaces (BCIs) have the potential to augment communication in individuals with impaired speech due to muscle weakness, for example in ALS and other neurological disorders. However, to achieve long-term, reliable use of a speech BCI, it is essential for speech-related neural signal changes to be stable over long periods of time. Here we study, for the first time, the stability of speech-related electrocorticographic (ECoG) signals recorded from a chronically implanted ECoG BCI over a 12 month period.
APPROACH
ECoG signals were recorded by an ECoG array implanted over the ventral sensorimotor cortex (vSMC) in a clinical trial participant with ALS. Because ECoG-based speech decoding has most often relied on broadband high gamma signal changes relative to baseline (non-speech) conditions, we studied longitudinal changes of high gamma band (HG) power at baseline and during speech, and we compared these with residual high frequency (HF) noise levels at baseline. Stability was further assessed by longitudinal measurements of signal-to-noise ratio (SNR), activation ratio (ActR), and peak speech-related HG response magnitude (HG response peaks). Lastly, we analyzed the stability of the event-related HG power changes (HG responses) for individual syllables at each electrode.
MAIN RESULTS
We found that speech-related ECoG signal responses were stable over a range of syllables activating different articulators for the first year after implantation.
SIGNIFICANCE
Together, our results indicate that ECoG can be a stable recording modality for long-term speech BCI systems for those living with severe paralysis.
CLINICALTRIALS
gov, registration number NCT03567213.
PubMed: 38925110
DOI: 10.1088/1741-2552/ad5c02 -
The Journal of Surgical Research Jun 2024Metabolic syndrome (MetS) is characterized by cardiometabolic abnormalities such as hypertension, obesity, diabetes, or dyslipidemia. This study aims to evaluate the...
INTRODUCTION
Metabolic syndrome (MetS) is characterized by cardiometabolic abnormalities such as hypertension, obesity, diabetes, or dyslipidemia. This study aims to evaluate the association of MetS on the postoperative outcomes of ventral, umbilical, and epigastric hernia repair using component separation.
METHODS
The American College of Surgeons National Surgical Quality Improvement Program database was used to identify patients who underwent ventral, umbilical, and epigastric hernia repair with component separation between 2015 and 2021. MetS status was defined as patients receiving medical treatment for diabetes mellitus and hypertension, with a body mass index greater than 30 kg/m. Propensity matching was performed to generate two balanced cohorts with and without MetS. T-tests and Fisher's Exact tests assessed group differences. Logistic regression models evaluated complications between the groups.
RESULTS
After propensity score matching, 3930 patients were included in the analysis, with 1965 in each group (MetS versus non-MetS). Significant differences were observed in the severity and clinical presentation of hernias between the groups. The MetS cohort had higher rates of incarcerated hernia (39.1% versus 33.2%; P < 0.001), and recurrent ventral hernia (42.7% versus 36.5%; P < 0.001) compared to the non-MetS cohort. The MetS group demonstrated significantly increased rates of renal insufficiency (P = 0.026), unplanned intubation (P = 0.003), cardiac arrest (P = 0.005), and reoperation rates (P = 0.002) than the non-MetS cohort. Logistic regression models demonstrated higher likelihood of postoperative complications in the MetS group, including mild systemic complications (OR 1.25; 95%CI 1.030-1.518; P = 0.024), severe systemic complications (OR 1.63; 95%CI 1.248-2.120; P < 0.001), and reoperation (OR 1.47; 95%CI 1.158-1.866; P = 0.002). There were no significant differences in the rates of 30-d wound complications between groups.
CONCLUSIONS
The presence of metabolic derangement appears to be associated with adverse postoperative medical outcomes and increased reoperation rates after hernia repair with component separation. These findings highlight the importance of optimizing preoperative comorbidities as surgeons counsel patients with MetS.
PubMed: 38925100
DOI: 10.1016/j.jss.2024.05.046 -
Anatomical Record (Hoboken, N.J. : 2007) Jun 2024Batoids (rays and skates) are cartilaginous fishes whose jaws are not articulated directly to the neurocranium. The only point of contact between them are the...
Batoids (rays and skates) are cartilaginous fishes whose jaws are not articulated directly to the neurocranium. The only point of contact between them are the hyomandibular cartilages, resulting in a unique mandibular suspension called euhyostyly. Due to this decoupling of the jaws from the skull, muscles play an essential role in modulating mandibular movements during the feeding process, especially during mandibular protrusion. The main objectives of our study were: (1) to examine the mandibular musculature of eight batoid species from different orders in the Batoidea and (2) establish a standardized musclulature terminology for future comparative myological studies in batoids. For each muscle bundle, the general characteristics of each cranial muscle were described and their origin and insertions were identified. The number of muscle bundles differed intraspecifically. On the dorsal surface, we reported the first evidence of the presence of the precranial muscle (PCM) in U. halleri, as well as the ethmoideo-parethmoidalis muscle (ETM) in R. velezi, P. glaugostigma and Z. exasperata; in addition, the insertion of the spiracularis muscle (SP) extended to the ventral surface of the oropharyngeal tract in myliobatiforms. On the ventral surface of the head, both N. entemedor and M. californica exhibited additional muscles in the mandibular area. These muscles were renamed as part of the standardization of mandibular terminology: the depressor mandibularis minor (DMM) in N. entemedor and the adductor mandibulae profundus (AMP) in M. californica. The standardization of terminology is essential for futures studies of the mandibular apparatus in batoids, to facilitate the morphological description of muscles in species without anatomical accounts and for continuity in broader comparative analyses.
PubMed: 38924302
DOI: 10.1002/ar.25527 -
Developmental Dynamics : An Official... Jun 2024Sex-specific morphogenesis occurs in Caenorhabditis elegans in the vulva of the hermaphrodite and in the male tail during the last larval stage. Temporal progression of... (Review)
Review
BACKGROUND
Sex-specific morphogenesis occurs in Caenorhabditis elegans in the vulva of the hermaphrodite and in the male tail during the last larval stage. Temporal progression of vulva morphogenesis has been described in fine detail. However, a similar precise description of male tail morphogenesis was lacking.
RESULTS
We here describe morphogenesis of the male tail at time points matching vulva development with special focus on morphogenesis of the tail tip. Using fluorescent reporters, we follow changes in cell shapes, cell fusions, nuclear migration, modifications in the basement membrane, and formation of a new apical extracellular matrix at the end of the tail.
CONCLUSION
Our analysis answers two open questions about tail tip morphogenesis (TTM) by showing that one of the four tail tip cells, hyp11, remains largely separate, while the other cells fully fuse with each other and with two additional tail cells to form a ventral tail syncytium. This merger of cells begins at the apical surface early during TTM but is only completed toward the end of the process. This work provides a framework for future investigations of cell biological factors that drive male tail morphogenesis.
PubMed: 38924277
DOI: 10.1002/dvdy.721 -
Mapping Motor Cortical Network Excitability and Connectivity Changes in De Novo Parkinson's Disease.Movement Disorders : Official Journal... Jun 2024Transcranial magnetic stimulation-electroencephalography (TMS-EEG) has demonstrated decreased excitability in the primary motor cortex (M1) and increased excitability in...
BACKGROUND
Transcranial magnetic stimulation-electroencephalography (TMS-EEG) has demonstrated decreased excitability in the primary motor cortex (M1) and increased excitability in the pre-supplementary motor area (pre-SMA) in moderate-advanced Parkinson's disease (PD).
OBJECTIVES
The aim was to investigate whether these abnormalities are evident from the early stages of the disease, their behavioral correlates, and relationship to cortico-subcortical connections.
METHODS
Twenty-eight early, drug-naive (de novo) PD patients and 28 healthy controls (HCs) underwent TMS-EEG to record TMS-evoked potentials (TEPs) from the primary motor cortex (M1) and the pre-SMA, kinematic recording of finger-tapping movements, and a 3T-MRI (magnetic resonance imaging) scan to obtain diffusion tensor imaging (DTI) reconstruction of white matter (WM) tracts connecting M1 to the ventral lateral anterior thalamic nucleus and pre-SMA to the anterior putamen.
RESULTS
We found reduced M1 TEP P30 amplitude in de novo PD patients compared to HCs and similar pre-SMA TEP N40 amplitude between groups. PD patients exhibited smaller amplitude and slower velocity in finger-tapping movements and altered structural integrity in WM tracts of interest, although these changes did not correlate with TEPs.
CONCLUSIONS
M1 hypoexcitability is a characteristic of PD from early phases and may be a marker of the parkinsonian state. Pre-SMA hyperexcitability is not evident in early PD and possibly emerges at later stages of the disease. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
PubMed: 38924157
DOI: 10.1002/mds.29901 -
The Veterinary Record Jun 2024Focused ultrasonographic imaging techniques are commonly used for cats and dogs; however, such techniques have not been described in rabbits.
BACKGROUND
Focused ultrasonographic imaging techniques are commonly used for cats and dogs; however, such techniques have not been described in rabbits.
METHODS
Focused abdominal ultrasonography was performed on 12 healthy conscious rabbits using four acoustic windows: xiphisternal, left and right renal and cystic. They were positioned in sternal recumbency on a table top, with a cut-out area to allow access to the ventral abdomen. Ultrasonographic images were obtained using a micro-convex probe (3‒11 MHz), and the organs identified in each image were recorded.
RESULTS
The liver, kidneys, stomach, duodenum, jejunum, caecum and colon were identified in all rabbits (12/12). In most rabbits, the following were identified: urinary bladder (11/12), gall bladder (11/12), spleen (10/12) and caudal vena cava or aorta (7/10). The right adrenal gland was identified in five of the 12 rabbits, but the left adrenal gland was identified in only one. The stomach filled at least one view in all rabbits, and the caecum filled the view in nine of 12 rabbits. Other structures thought to be identified included caecal flexures (9/12), appendix (9/12), ampulla coli (3/12), sacculus rotundus (3/12), colonic haustrae (2/12) and pancreas (2/12).
LIMITATION
Only neutered individuals were imaged, so the usefulness of the technique for imaging the reproductive organs could not be determined.
CONCLUSION
This technique enabled imaging of the major abdominal organs in most rabbits, demonstrating the potential value of focused imaging in this species.
PubMed: 38923531
DOI: 10.1002/vetr.4087