The influence of olfactory experience on the birthrates of olfactory sensory neurons with specific odorant receptor identities.

Olfactory sensory neurons (OSNs) are one of a few neuron types that are generated continuously throughout life in mammals. The persistence of olfactory sensory neurogenesis beyond early development has long been thought to function simply to replace neurons that are lost or damaged through exposure to environmental insults. The possibility that olfactory sensory neurogenesis may also serve an adaptive function has received relatively little consideration, largely due to the assumption that the generation of new OSNs is stochastic with respect to OSN subtype, as defined by the single odorant receptor gene that each neural precursor stochastically chooses for expression out of hundreds of possibilities. Accordingly, the relative birthrates of different OSN subtypes are predicted to be constant and impervious to olfactory experience. This assumption has been called into question, however, by evidence that the birthrates of specific OSN subtypes can be selectively altered by manipulating olfactory experience through olfactory deprivation, enrichment, and conditioning paradigms. Moreover, studies of recovery of the OSN population following injury provide further evidence that olfactory sensory neurogenesis may not be strictly stochastic with respect to subtype. Here we review this evidence and consider mechanistic and functional implications of the prospect that specific olfactory experiences can regulate olfactory sensory neurogenesis rates in a subtype-selective manner.

Transapical balloon dilation of cor triatriatum sinister in a cat.

A hybrid surgical approach was utilized to address cor triatriatum sinister in a 10-month-old castrated male domestic shorthair cat. Prior to surgery, open-mouth breathing occurred with exertion. The procedure was guided by transesophageal echocardiography and fluoroscopy. A minithoracotomy was performed, and the left atrial membrane was accessed via an introducer placed through the left ventricular apex. Sequential balloon dilations were performed, and the mean transmembrane gradient under anesthesia was reduced from 16 mmHg to 2.23 mmHg. Four months after surgery, the transmembrane mean gradient remained lower than prior to intervention. The cat tolerated surgery well and remains free of clinical signs nine months after surgery.

Third-degree atrioventricular block secondary to infiltrative cardiac hemangiosarcoma in a dog.

A nine-year-old male, castrated Pembroke Welsh Corgi presented with a two-month history of lethargy, hyporexia, and occasional vomiting. There was also a two-week history of exercise intolerance; no syncopal episodes were reported. Auscultation revealed bradycardia with an irregular rhythm and otherwise normal heart and lung sounds. Third-degree atrioventricular block was diagnosed. Two-dimensional transthoracic echocardiography revealed a soft tissue structure arising from the atrioventricular junction and interatrial septum. There was scant abdominal effusion. Pacemaker implantation was offered, but the owner elected humane euthanasia due to the unknown prognosis. Necropsy was consistent with cardiac hemangiosarcoma infiltrating the interatrial and interventricular septum.

Better Understanding of the Metamorphosis of Pregnancy (BUMP): protocol for a digital feasibility study in women from preconception to postpartum.

The Better Understanding the Metamorphosis of Pregnancy (BUMP) study is a longitudinal feasibility study aimed to gain a deeper understanding of the pre-pregnancy and pregnancy symptom experience using digital tools. The present paper describes the protocol for the BUMP study. Over 1000 participants are being recruited through a patient provider-platform and through other channels in the United States (US). Participants in a preconception cohort (BUMP-C) are followed for 6 months, or until conception, while participants in a pregnancy cohort (BUMP) are followed into their fourth trimester. Participants are provided with a smart ring, a smartwatch (BUMP only), and a smart scale (BUMP only) alongside cohort-specific study apps. Participant centric engagement strategies are used that aim to co-design the digital approach with participants while providing knowledge and support. The BUMP study is intended to lay the foundational work for a larger study to determine whether participant co-designed digital tools can be used to detect, track and return multimodal symptoms during the perinatal window to inform individual level symptom trajectories.

Dilated cardiomyopathy in cats: survey of veterinary cardiologists and retrospective evaluation of a possible association with diet.

INTRODUCTION/OBJECTIVES: The objectives were to conduct a survey of cardiologists on their recent experiences with cats that have dilated cardiomyopathy (DCM) and to retrospectively review individual cases of feline DCM. ANIMALS, MATERIALS AND METHODS: Part one: A survey was distributed to cardiologists with questions regarding caseload and clinical management of cats with DCM diagnosed over the past two years. Part two: Cardiologists completing the survey were invited to submit data from cats recently diagnosed with DCM. Data on signalment, clinical signs, diet, echocardiographic measurements and outcome were recorded. RESULTS: Part one: From 52 completed surveys, many cardiologists responded that measuring and supplementing taurine and recommending a diet change in cats with DCM are common practices. Few (15%) cardiologists reported an increase in the number of feline DCM cases over the past two years, although some had cases that improved even if taurine deficiency was not present. Part two: Twenty of 37 (54%) cats ate low pea/lentil (low PL) diets, and 14/37 (38%) ate high PL diets at the time of diagnosis; three had incomplete diet information. Two of 13 cats (15%) in which taurine was measured had levels below the reference range. After adjusting for other variables, cats eating high PL diets that changed diets after diagnosis had a significantly longer survival time than that of cats eating high PL diets that did not change diets after diagnosis (P = 0.025). CONCLUSIONS: Additional research is warranted to determine whether there could be a possible association between diet and DCM in cats.

Synchronous diaphragmatic contraction associated with dual-chamber transvenous pacing in a dog.

A 3-year-old, 20-kg, spayed female, mix-breed dog received a dual-chamber pacemaker for management of symptomatic 3rd-degree atrioventricular block. Synchronous diaphragmatic contraction was documented to occur with atrial pacing. Various methods to reduce the occurrence of pacemaker-related phrenic nerve stimulation are discussed.

Extracardiac intrapericardial myxosarcoma causing right ventricular outflow tract obstruction in a dog.

A 13-year-old male castrated pomeranian cross was referred for evaluation of episodes of collapse and a suspected cardiac mass. The presence of a mass at the base of the heart within the pericardial space was confirmed by echocardiography. Additional diagnostics included computed tomography, ultrasound-guided fine-needle aspirate, and thoracic radiographs. The mass was surgically debulked and diagnosed as myxosarcoma via histopathology. This case report describes the diagnostic imaging, laboratory findings, and short-term positive clinical outcome of a dog with a myxosarcoma in a previously undescribed location.

One haploid parent contributes 100% of the gene pool for a widespread species in northwest North America.

The monoicous peatmoss Sphagnum subnitens has a tripartite distribution that includes disjunct population systems in Europe (including the Azores), northwestern North America and New Zealand. Regional genetic diversity was highest in European S. subnitens but in northwestern North America, a single microsatellite-based multilocus haploid genotype was detected across 16 sites ranging from Coos County, Oregon, to Kavalga Island in the Western Aleutians (a distance of some 4115 km). Two multilocus haploid genotypes were detected across 14 sites on South Island, New Zealand. The microsatellite-based regional genetic diversity detected in New Zealand and North American S. subnitens is the lowest reported for any Sphagnum. The low genetic diversity detected in both of these regions most likely resulted from a founder event associated with vegetative propagation and complete selfing, with one founding haploid plant in northwest North America and two in New Zealand. Thus, one plant appears to have contributed 100% of the gene pool for the population systems of S. subnitens occurring in northwest North America, and this is arguably the most genetically uniform group of plants having a widespread distribution yet detected. Although having a distribution spanning 12.5° of latitude and 56° of longitude, there was no evidence of any genetic diversification in S. subnitens in northwest North America. No genetic structure was detected among the three regions, and it appears that European plants of S. subnitens provided the source for New Zealand and northwest North American populations.

[Increased QRS voltage during dehydrating].

AIM: To assess QRS voltage changes with lower total amount of biological fluids under ultrafiltration during hemodialysis. MATERIALS AND METHODS: The study included 14 patients with chronic renal failure. An average of 2.5 +/- 0.24 liters of fluid were removed during a session. 12-lead standard ECG was continuously recorded by means of a computer-aided cardiac recorder throughout the session of hemodialysis. Changes in the amplitude of QRS waves were analyzed in each lead. RESULTS: Elevated QRS voltage was most pronounced in the anterior chest leads (v1-v4). Moreover, the potentials corresponding to the propagation of a predominant excitation front over the cardiac surface facing both the anterior chest wall--QRS+ (R wave) and the posterior chest wall--ORS-(S or Q waves) increased in most cases. Voltage changes in these leads were observed in 90% of patients, the amplitude of the waves being increased by more than 0.5 mV. CONCLUSION: During dehydration, lower chest tissue electroconductivity may cause a considerable increase in QRS voltage. This should be kept in mind while analyzing ECG data during both a session of hemodialysis and antihypertensive therapy resulting in some fluid loss, as well as in the treatment of cardiac and renal failure, leading to diminished concomitant edemas.