Venipuncture Site Influences Blood-drop Volume in C57BL/6 Mice.

Many experiments require the collection of serial blood samples from mice. However, the size of mice limits the volume of blood that can be safely collected as a survival procedure. In IACUC protocols, investigators may report the amount of blood they collect from mice as a number of drops. Many institutions, including ours, use an anecdotal conversion factor (1 drop of mouse blood = 25 µL) to ensure that blood-collection volumes are compliant with institutional guidelines. To our knowledge, previous work has not experimentally determined the volume of a drop of mouse blood. In this 10-wk crossover experiment, 2 phlebotomists bled 30 C57BL/6J mice from 3 sites (facial, saphenous, and tail) using one or 2 different needle gauge sizes per site. Male and female mice were weighed weekly and divided among 5 groups (n = 6): left and right tail vein, left and right saphenous vein, and facial vein. A single blood drop from each site was weighed, and the volume of each drop was calculated using the average blood density determined from 8 mice terminally bled at the end of the study. Venipuncture site and side significantly influenced blood-drop weight and thus calculated volume. Facial vein puncture produced the largest drop volume (mean: 21.7 µL), followed by the saphenous vein (mean: 9.97 µL) and tail vein (mean: 4.96 µL). Collection from the facial vein was associated with more hemorrhage and morbidity. Left-sided venipuncture was associated with slightly larger-volume blood drops, though the effect size of side was small. The results of this study may be useful in more accurately estimating blood loss via conversion of drops to volume. Our data indicate that blood collection from saphenous and tail veins minimizes blood loss relative to facial vein puncture and may optimize both serial collection of small-volume blood samples and animal welfare.

Secondary peritonitis in a patient with cirrhosis involving Hyphopichia burtonii, an emerging fungal pathogen.

We present a case where Hyphopichia burtonii, a yeast, speciated from peritoneal fluid in a cirrhotic patient with secondary peritonitis. The patient, a man in his 60s with decompensated cirrhosis, was admitted for an upper gastrointestinal (GI) bleed. On admission, he was treated empirically for spontaneous bacterial peritonitis (SBP) but failed to improve with antibiotics. Serial paracenteses revealed polymicrobial peritonitis and rising peritoneal polymorphonuclear leukocytes (PMNs). These findings raised concerns for secondary peritonitis, prompting an abdominal computed tomography (CT) scan which revealed ischemic bowel. Among the peritoneal microbiota isolated, Hyphopichia burtonii predominated. Hyphopichia burtonii has only recently been reported as a human pathogen, previously it had only reported as a pathogen in bats[1,2].

The Impact of Underlying Obstructive Sleep Apnea Treatment on Exercise Capacity in Patients With Pulmonary Hypertension Undergoing a Cardiac Rehabilitation Program.

PURPOSE: Obstructive sleep apnea (OSA)-related pulmonary hypertension (PH) can often be reversed with treatment of OSA via continuous positive airway pressure. We hypothesized that treatment of OSA would be associated with a greater improvement in exercise capacity (EC) with cardiac rehabilitation (CR), especially in patients with PH as compared with those who are untreated. METHODS: We reviewed medical records of 315 consecutive patients who participated in CR. Pulmonary hypertension status was assessed on the basis of peak tricuspid regurgitant velocity (>2.8 m/sec) on pre-CR echocardiograms. The OSA status (no, untreated, or treated OSA) was determined on the basis of results from sleep studies, continuous positive airway pressure device data, and physician notes. Exercise capacity was assessed by measuring metabolic equivalents (METs) using a treadmill stress test before and after CR. RESULTS: We included 290 patients who participated in CR with available echocardiographic data: 44 (15%) had PH, and 102 (35%) had known OSA (30 treated and 72 untreated). Patients with OSA versus those with no OSA were more likely to have PH ( P = .06). Patients with PH versus no-PH were associated with significantly lower baseline METs in crude and adjusted analyses ( P ≤. 004). The PH and OSA status in isolation were not associated with changes in METs ( P > .2) with CR. There was a significant interaction between OSA treatment and PH in crude and adjusted analyses ( P ≤.01): treatment vs no treatment of OSA was associated with a clinically and statistically greater improvement in METs in patients who participated in CR with but not without PH. CONCLUSION: Baseline PH was associated with decreased baseline EC but did not attenuate CR-related improvements in METs. However, in the subset of OSA patients with PH, OSA therapy was associated with improved EC after CR.

Spontaneous Pituitary Neoplasm in Two Female Geriatric Southern Giant Pouched Rats (Cricetomys ansorgei).

Southern giant pouched rats (Cricetomys ansorgei) are a small muroid species native to the sub-Saharan Africa. Their exceptionally developed olfactory system, trainability, and relatively small size makes them useful working animals for various applications in humanitarian work. At our institution, a breeding colony of Southern giant pouched rats is maintained to study their physiology and utility as scent detectors. This case report describes the occurrence of spontaneous pituitary neoplasms with distinct clinical presentations in 2 geriatric (approximately 7.5 y old) wild-caught female Southern giant pouched rats. The first pouched rat displayed vestibular deficits, including left-sided head tilt, ataxia, disorientation, and circling. MRI revealed a large, focal heterogeneous mass arising from the pituitary fossa. The second pouched rat presented with polyuria, polydipsia, and hyperglycemia but no neurologic signs. Examination after euthanasia revealed a prolactin (PRL)-expressing pituitary carcinoma and adenoma in the first and second pouched rat, respectively, associated with mammary hyperplasia in both animals. This is the first report of spontaneous PRL-producing pituitary tumors in Southern giant pouched rats.

Comparison of Effects of Capromorelin and Mirtazapine on Appetite in New Zealand White Rabbits (Oryctolagus cuniculus).

Inappetence is a welfare concern in rabbits (Oryctolagus cuniculus), as it can lead to potentially fatal gastrointestinal stasis. In other species, inappetence is commonly treated with appetite stimulants; however, few published studies have evaluated the efficacy of appetite stimulants in rabbits. We performed 2 studies to evaluate the effects of capromorelin and mirtazapine on appetite in New Zealand White (NZW) rabbits. In the first study, healthy rabbits ( n = 9) were evaluated using a randomized crossover design and 9 treatments: capromorelin 4 mg/kg oral (PO) once a day (SID), capromorelin 8 mg/kg PO SID, saline control PO SID, capromorelin 4 mg/kg PO twice a day (BID), capromorelin 8 mg/kg PO BID, saline control PO BID, mirtazapine 0.5 mg/kg transdermal (TD) SID, mirtazapine 1 mg/kg TD SID, and saline control TD SID for 3 d with a 1-wk washout period between treatments. Treatment efficacy was assessed by measuring daily feed intake and fecal output and by weighing rabbits twice a week. Overall, feed intake and fecal output were higher for all treatments as compared with controls, except for fecal output in the capromorelin 4 mg/kg and 8 mg/kg PO SID groups. Feed intake and fecal output were significantly higher with mirtazapine as compared with capromorelin. Body weight and erythema/petechia of the pinnae were greater in the mirtazapine 1 mg/kg TD SID group than in the control group. A second study evaluated rabbits that had undergone surgery (castration, n = 7) and then received one of 3 treatments: capromorelin 8 mg/kg PO BID, mirtazapine 1 mg/kg TD SID, or saline PO BID for 3 d postoperatively. Feed intake and fecal output in the postoperative mirtazapine group were not significantly different from those of the capromorelin and control groups. Due to its superior efficacy as compared with capromorelin in healthy NZW rabbits, we recommend considering mirtazapine as a treatment for inappetence in NZW rabbits.

Animal Models of Bone Marrow Lesions in Osteoarthritis.

Bone marrow lesions are abnormalities in magnetic resonance images that have been associated with joint pain and osteoarthritis in clinical studies. Increases in the volume of bone marrow lesions have been associated with progression of joint degeneration, leading to the suggestion that bone marrow lesions may be an early indicator of-or even a contributor to-cartilage loss preceding irreversible damage to the joint. Despite evidence that bone marrow lesions play a role in osteoarthritis pathology, very little is known about the natural history of bone marrow lesions and their contribution to joint degeneration. As a result, there are limited data regarding the cell activity within a bone marrow lesion and any associated bone-cartilage cross-talk. Animal models provide the best approach for understanding bone marrow lesions at their early, reversible stages. Here, we review the few animal studies of bone marrow lesions. An ideal animal model of a bone marrow lesion occurs in joints large enough to accurately measure bone marrow lesion volume. Additionally, the ideal animal model would facilitate the study of bone-cartilage cross-talk by generating the bone marrow lesion immediately adjacent to subchondral bone and would do so without causing direct damage to neighboring soft tissues to isolate the effects of the bone marrow lesion on cartilage loss. Early reports demonstrate the feasibility of such an animal model. Given the irreversible nature of osteoarthritic changes in the joint, factors such as bone marrow lesions that are present early in disease pathogenesis remain an enticing target for new therapeutic approaches. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Effects of Cisapride, Buprenorphine, and Their Combination on Gastrointestinal Transit in New Zealand White Rabbits.

Due to their effective analgesic properties, opioids are worthy of consideration for pain management in rabbits. However, this class of drugs causes undesirable effects including reduced gastrointestinal (GI) motility, reduced fecal output, and delays GI transit times and thus increases the risk of GI stasis. The risk of stasis discourages the use of opioids in rabbits, which could affect animal welfare. Gastroprokinetic agents such as cisapride are effective in promoting gastric emptying in many species, but whether this effect occurs in rabbits is unknown. This study assessed the efficacy of cisapride when administered as a single agent and in combination with buprenorphine in rabbits; efficacy was assessed by measuring GI transit times, fecal output, body weight, and food and water intake. Female New Zealand White rabbits (n = 10) were studied in a crossover, randomized design and received either vehicle and buprenorphine, cisapride and saline, cisapride and buprenorphine, or vehicle and saline (control) every 8 h for 2 d. Rabbits were anesthetized and administered radio-opaque, barium-filled spheres via orogastric tube. Feces was assessed via radiography for detection of the barium-spheres to determine GI transit time. GI transit time was significantly longer in buprenorphine groups than in control groups, regardless of the use of cisapride. Fecal output and food and water intake were lower for buprenorphine groups than control groups. Cisapride did not significantly alter GI transit, fecal output, or food and water intake. In addition, treatment group did not significantly affect body weight. In conclusion, buprenorphine treatment (0.03 mg/kg TID) prolonged GI transit time and reduced fecal output and food and water consumption in rabbits. Coadministration of buprenorphine and cisapride (0.5 mg/kg) did not ameliorate these effects, and the administration of cisapride at this dose did not appear to affect GI motility in female rabbits.

Vaginal Dysplasia and HIV: An African American and Caribbean American Cohort Study.

BACKGROUND: Vaginal cancer is a rare disease with poor clinical outcomes and limited therapeutic options. In the United States (US), minority women and older women are disproportionately diagnosed with late-stage vaginal cancer. Sociodemographic characteristics, risk behaviors, and cooccurring conditions are linked to vaginal intraepithelial neoplasia (VaIN). The diagnosis of VaIN is more prevalent among older women and women living with HIV (WLWH). The Caribbean basin has one of the highest rates of anogenital cancers in the Western Hemisphere. In the US, vaginal infections are more prevalent among Caribbean women, and these infections contribute to higher rates of Human Papilloma Virus (HPV). Given the high rate of anogenital cancers in the Caribbean and the high rates of HPV among Caribbean women in the US, we sought to describe the occurrence of VaIN in a cohort of Black non-Hispanic WLWH. The cohort was followed by an interdisciplinary team of providers with the University of Miami, Miller School of Medicine. RESULTS: Caribbean Americans were living with HIV longer and more were uninsured; more African Americans endorsed cigarette and illicit substance use. Caribbean Americans trended towards the highest grades of VaIN (VaIN 2+) at baseline, but more African Americans progressed to VaIN 2+ in subsequent biopsies. CONCLUSION: In this cohort of Caribbean American and African American women living with HIV diagnosed with VaIN, Caribbean Americans had the highest grade of VaIN at baseline, but more African Americans progressed to more advanced stages of the disease.

Harnessing mHealth technologies to increase physical activity and prevent cardiovascular disease.

Research into prevention of cardiovascular disease has increasingly focused on mobile health (mHealth) technologies and their efficacy in helping individuals adhere to heart-healthy recommendations, including daily physical activity levels. By including the use of mHealth technologies in the discussion of physical activity recommendations, clinicians empower patients to play an active daily role in modifying their cardiovascular risk-factor profile. In this review, we critically evaluate the mHealth and physical activity literature to determine how these tools may lower cardiovascular risk while providing real-time tracking, feedback, and motivation on physical activity levels. We analyze the various domains-including user knowledge, social support, behavioral change theory, and self-motivation-that potentially influence the effectiveness of smartphone applications to impact individual physical activity levels. In doing so, we hope to provide a thorough overview of the mHealth landscape, in addition to highlighting many of the administrative, reimbursement, and patient-privacy challenges of using these technologies in patient care. Finally, we propose a behavioral change model and checklist for clinicians to assist patients in utilizing mHealth technology to best achieve meaningful changes in daily physical activity levels.

Barriers to Hepatitis C Screening in a Minority Population: A Comparison of Hepatitis C and Human Immunodeficiency Virus Screening Rates at a Community STD Clinic in Miami, Florida.

METHODS: 357 patients at a free STD clinic in Miami, FL were screened for HCV. Surveys were administered assessing risk factors for infectious disease transmission, and HCV and HIV screening history. RESULTS: 15.1% of participants had been screened for HCV before whereas 83.8% had been screened for HIV (n = 356). Of the patients previously screened for HCV (n = 54), 98.2% of these patients had previously been screened for HIV as well. CONCLUSION: This data shows the low prevalence of prior HCV screenings in a high-risk population in Miami, FL. Participants who had previously received an HIV screening test were more likely to report receiving a prior HCV screening. Despite the high prevalence of HCV, most HCV infections are undiagnosed. Mortality from HIV has been declining in the United States while mortality from HCV is increasing. To decrease HCV related mortality, we recommend offering HCV screening in conjunction with HIV screening.

A Novel, Minimally-Invasive Approach to Repair Degenerative Disk Disease in an Ovine Model Using Injectable Polymethyl-Methacrylate and Bovine Collagen (PMMA/BC).

BACKGROUND: The natural, inflammatory repair processes of an injured intervertebral degenerative disc can propagate further injury and destruction. While there are many different treatment modalities of the pain related to degenerative disc disease, none are actually reparative in nature. Treatment strategies to repair a degenerative disc without inducing a destructive inflammatory milieu have been elusive.  PURPOSE: The purpose of this experiment is to discover the feasibility of reconstructing an injured intervertebral disc using an injected, inert polymer as the foundation for endogenous collagen growth. STUDY DESIGN: In this ovine model of six subjects in total, we introduce a modality where a large inert polymer, polymethyl methacrylate (PMMA), in conjunction bovine collagen (BC) is injected into the intervertebral disc. Following six months of observation, histologic specimens were evaluated macroscopically and microscopically for evidence of a benefit of the injectable PMMA/BC. METHODS: We obtained six merino sheep for this study. Concentric injuries were made to four of their lumbar intervertebral discs. Two of those levels were treated with a percutaneous injection of 0.3 cc of PMMA/BC. The remaining lumbar levels were left untreated and were our controls. After six months, all subjects were sacrificed. Their four levels were extracted and were examined macroscopically and microscopically. RESULTS: All subjects tolerated the lumbar injury and percutaneous injection of PMMA/BC well. After the six month interval, all subjects have demonstrated an intact architecture of their lumbar disc height at the macroscopic and microscopic level. Microscopically, there was no evidence of external migration of the PMMA/BC microspheres, nor was there any evidence of an inflammatory response by its presence. Notably, the PMMA/BC microspheres were well-incorporated into the concentric disc tears and had undergone endogenous collagen formation in its environment. Treatment levels were revealing for maintenance of disc height without evidence of an ongoing degeneration. The controlled levels were revealing for continued disc degeneration with loss of disc height and evolving injury at the level of the concentric tear. CONCLUSIONS: This ovine model demonstrates a novel and promising technique for prevention and arrest of lumbar intervertebral disc degeneration.

Novel Transabdominal Motor Action Potential (TaMAP) Neuromonitoring System for Spinal Surgery.

INTRODUCTION: Minimally invasive lateral lumbar interbody fusion (LLIF) approaches to the lumbar spine reduce patient morbidity compared to anterior or posterior alternatives. This approach, however, decreases direct anatomical visualization, creating the need for highly sensitive and specific neurophysiological monitoring. We seek to determine feasibility in 'transabdominal motor action potential (TaMAP)' monitoring as an assessment for the integrity of the neural elements during lateral-approach surgeries to the lumbar spine. METHODS: Cathode and anode leads were placed on the posterior and anterior surfaces of two porcine subjects. Currents of varying degrees were transmitted across, from front to back. Motor responses were monitored and recorded by needle electrodes in specific distal muscle groups of the lower extremity. Lastly, the cathode and anode were placed anterior and posterior to the chest wall and stimulated to the maximum of 1500 mA to determine any effect on cardiac rhythm. RESULTS: Responses were seen by measuring vertical height differences between peaks of corresponding evoked potentials. Recruitment began at 200 mA in the lower extremities. Stimulation at 450 mA recruited a reliable and distinguishable electrographic response from most muscle groups. Responses were recorded and reliably measured and increased in proportion to the graduation of transabdominal stimulation current; no responses were seen in the arms or face. 1500 mA across the chest wall failed to stimulate or induce cardiac arrhythmia on repeated stimulation, indicating safety of stimulation. CONCLUSION: TaMAPs seen in the animal model provide a potential alternative to standard transcranial motor evoked potentials done in the lateral approach of LLIFs. TaMAP recordings in most muscle groups were recordable and reliable, though some muscle groups failed to stimulate. Safety of transabdominal motor evoked potentials was confirmed in this porcine study. Future studies should examine TaMAPs reliability in detecting compressive lesions of nerve roots and peripheral nerves.

Cadaveric Analysis of the Kambin's Triangle.

Introduction Kambin's Triangle is a right triangle over the dorsolateral disc. The area of this right triangle currently serves as a strategic site of posterolateral, minimally invasive access to the nerve root for delivery of epidural steroid injections. This posterolateral approach has also been considered a safe area of access to the intervertebral disc space and, thus, an effective approach in reducing complications, such as violation of the thecal sac, the nerve root, or the bony elements of the spine during minimally invasive spinal surgery. No published studies have been performed to characterize the dimensions of the Kambin's Triangle. Our aim is to characterize its dimensions at the lumbar levels and determine its efficacy and safety as a site of access for minimally invasive spinal surgery. Methods Two randomly chosen adult male cadavers were used for this study. The measurements were made bilaterally at their lumbar levels (L1-L5), which equates to 16 total measurements (eight bilateral disc spaces on two cadavers). The disc space was first accessed using a Kirschner wire in a standard oblique approach. With the assistance of fluoroscopy, a Kirschner wire was passed into the disc through the Kambin's Triangle. The procedure was performed on the cadavers bilaterally at four levels, followed by open dissection. The calculations of the area were made by measuring the exiting nerve root, the superior border of the caudal vertebra, and the superior articulating facet-the borders of the Kambin's Triangle. Results The Kambin's Triangle height and width respectively averaged at 12 mm and 10 mm (L1-L2), 13 mm and 11 mm (L2-L3), 17 mm and 11 mm (L3-L4), and 18 mm and 12 mm (L4-L5). Thus, the area at each level was 60 mm(2) (L1-L2), 71.5 mm(2) (L2-L3), 93.5 mm(2) (L3-L4), and 108 mm(2) (L4-L5). All dissected levels demonstrated adequate anchoring of the Kirschner wire into the disc space with no evidence of nerve injury. Following this, a retractor was placed and complete discectomies were performed. All exiting nerves were protected in this safe zone and the thecal sac remained inviolate. Conclusion Understanding the Kambin's Triangle will assist surgeons in the minimally invasive approach to spinal surgeries, with potentially safe placement of interbody cages through this strategic space.

Limbform: a functional ontology-based database of limb regeneration experiments.

SUMMARY: The ability of certain organisms to completely regenerate lost limbs is a fascinating process, far from solved. Despite the extraordinary published efforts during the past centuries of scientists performing amputations, transplantations and molecular experiments, no mechanistic model exists yet that can completely explain patterning during the limb regeneration process. The lack of a centralized repository to enable the efficient mining of this huge dataset is hindering the discovery of comprehensive models of limb regeneration. Here, we introduce Limbform (Limb formalization), a centralized database of published limb regeneration experiments. In contrast to natural language or text-based ontologies, Limbform is based on a functional ontology using mathematical graphs to represent unambiguously limb phenotypes and manipulation procedures. The centralized database currently contains >800 published limb regeneration experiments comprising many model organisms, including salamanders, frogs, insects, crustaceans and arachnids. The database represents an extraordinary resource for mining the existing knowledge of functional data in this field; furthermore, its mathematical nature based on a functional ontology will pave the way for artificial intelligence tools applied to the discovery of the sought-after comprehensive limb regeneration models.

A bioinformatics expert system linking functional data to anatomical outcomes in limb regeneration.

Amphibians and molting arthropods have the remarkable capacity to regenerate amputated limbs, as described by an extensive literature of experimental cuts, amputations, grafts, and molecular techniques. Despite a rich history of experimental efforts, no comprehensive mechanistic model exists that can account for the pattern regulation observed in these experiments. While bioinformatics algorithms have revolutionized the study of signaling pathways, no such tools have heretofore been available to assist scientists in formulating testable models of large-scale morphogenesis that match published data in the limb regeneration field. Major barriers preventing an algorithmic approach are the lack of formal descriptions for experimental regenerative information and a repository to centralize storage and mining of functional data on limb regeneration. Establishing a new bioinformatics of shape would significantly accelerate the discovery of key insights into the mechanisms that implement complex regeneration. Here, we describe a novel mathematical ontology for limb regeneration to unambiguously encode phenotype, manipulation, and experiment data. Based on this formalism, we present the first centralized formal database of published limb regeneration experiments together with a user-friendly expert system tool to facilitate its access and mining. These resources are freely available for the community and will assist both human biologists and artificial intelligence systems to discover testable, mechanistic models of limb regeneration.