Carotid endarterectomy using regional anesthesia: technique and considerations.

Background: Carotid endarterectomy (CEA) is one of the most effective operations in minimizing stroke risk in both symptomatic and asymptomatic patients with carotid stenosis in the United States. Awake CEA with regional anesthesia may decrease both perioperative complications and length of hospital stay. Techniques of performing awake CEA is not often described in published literature. Objective: To describe our experience with CEA using regional anesthesia with a focus on patient selection, anatomic variations, and surgical technique including cervical regional block. We particularly focus on nuances of the awake approach. Methods: CEA using regional anesthesia is described in detail. Results: Successful use of regional anesthesia during CEA without complication. Conclusion: Regional anesthesia for CEA is an advantageous approach for cervical plaque removal in appropriate patients. Thoughtful patient selection, as well as understanding of anatomy and its variants, is required. Potential advantages and disadvantages are discussed.

Early Celecoxib Use in Spontaneous Intracerebral Hemorrhage is Associated with Reduced Mortality.

BACKGROUND: Hemorrhagic strokes constitute 10-15% of all strokes and have the worst mortality and morbidity of all subtypes. Mortality and morbidity of spontaneous intracerebral hemorrhage (sICH) are often secondary to the effects of inflammation, brain edema, and swelling. Studies have shown that celecoxib, a selective cyclooxygenase 2 (COX-2) inhibitor, reduces perihematomal edema formation and inflammation. This study aimed to examine the impact of celecoxib on sICH outcomes. METHODS: TriNetX, a multi-institutional research database, was retrospectively queried to identify patients with sICH. Outcomes in patients who received celecoxib within 5 days (cohort 1) were analyzed and compared to those in patients who did not receive celecoxib (cohort 2). The primary end point was mortality within 1 year of sICH. Secondary end points included ventilator dependence, tracheostomy, percutaneous endoscopic gastrostomy tube placement, craniotomy, deep venous thrombosis, pulmonary embolism, ischemic stroke, transient ischemia attack, myocardial infarction, and seizures. Further analysis was performed to assess these outcomes for patients treated with ibuprofen, a nonselective COX inhibitor. RESULTS: After propensity score matching, 833 patients were identified in each cohort based on celecoxib use. Mortality at 1 year was significantly reduced in patients with sICH receiving celecoxib compared to those who did not (13.33% vs. 17.77%; p = 0.0124). Risks of ventilator dependence, tracheostomy, percutaneous endoscopic gastrostomy tube placement, craniotomy, deep venous thrombosis, pulmonary embolism, ischemic stroke, transient ischemia attack, myocardial infarction, and seizures were not significantly increased in patients who received celecoxib within 5 days of sICH compared to those who did not receive celecoxib. There was no significant difference in mortality between patients based on ibuprofen administration. CONCLUSIONS: There exists a growing interest in using COX-2 as a potential target strategy for neuroprotection in patients with sICH, with some evidence of a mortality benefit in small cohort studies. This study shows that early celecoxib use is associated with decreased mortality in patients with sICH.

Nationwide trends in intensive care unit utilization in the elective endovascular treatment of unruptured intracranial aneurysms.

OBJECTIVE: Multiple studies suggest routine post-operative intensive care unit (ICU) stays after endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs) is unnecessary, though rates of ICU utilization nationwide are unknown. We aim to evaluate rates and characteristics of ICU utilization in patients undergoing elective endovascular repair of UIAs. METHODS: This is a retrospective cohort study utilizing a nationwide private-payer database in the United States to evaluate the ICU utilization in patients undergoing elective endovascular repair of UIAs between 2005 and 2019. Demographics and pre-operative comorbidities as well as post-procedural complications and discharge status were compared. An analysis of charges and costs was also performed. RESULTS: Among 6218 patients who underwent elective EVT of a UIA, 4890 (78.6%) were admitted to the ICU post-operatively. There were no differences in age, sex, or Charlson comorbidity scores in patients admitted to the ICU post-operatively compared to those admitted elsewhere. ICU utilization was more common in urban locations compared to rural. 12.7% of patients had ICU-specific needs sufficient to be billed by a critical care provider. Total provider costs were significantly higher in patients utilizing the ICU post-operatively, even among uncomplicated patients with routine discharges. CONCLUSION: Most patients undergoing elective endovascular UIA repair in the United States are admitted to the ICU postoperatively. Only 12.7% have ICU needs, and these patients are predictable from pre-operative characteristics or peri-operative complications. Reducing ICU use in this subgroup of patients may be an important target to improve healthcare value in this patient population.

Awake craniotomies in the pediatric population: a systematic review.

OBJECTIVE: Awake craniotomy (AC) is employed to maximize tumor resection while preserving neurological function in eloquent brain tissue. This technique is used frequently in adults but remains poorly established in children. Its use has been limited due to concern for children's neuropsychological differences compared with adults and how these differences may interfere with the safety and feasibility of the procedure. Among studies that have reported pediatric ACs, complication rates and anesthetic management vary. This systematic review was performed to comprehensively analyze outcomes and synthesize anesthetic protocols of pediatric ACs. METHODS: The authors followed PRISMA guidelines to extract studies that reported AC in children with intracranial pathologies. The Medline/PubMed, Ovid, and Embase databases were searched from database inception to 2021, using the terms ("awake") AND ("Pediatric*" OR "child*") AND (("brain" AND "surgery") OR "craniotomy"). Data extracted included patient age, pathology, and anesthetic protocol. Primary outcomes assessed were premature conversion to general anesthesia, intraoperative seizures, completion of monitoring tasks, and postoperative complications. RESULTS: Thirty eligible studies published from 1997 to 2020 were included that described a total of 130 children ranging in age from 7 to 17 years who had undergone AC. Of all patients reported, 59% were male and 70% had left-sided lesions. Procedure indications included the following etiologies: tumors (77.6%), epilepsy (20%), and vascular disorders (2.4%). Four (4.1%) of 98 patients required conversion to general anesthesia due to complications or discomfort during AC. In addition, 8 (7.8%) of 103 patients experienced intraoperative seizures. Furthermore, 19 (20.6%) of 92 patients had difficulty completing monitoring tasks. Postoperative complications occurred in 19 (19.4%) of 98 patients and included aphasia (n = 4), hemiparesis (n = 2), sensory deficit (n = 3), motor deficit (n = 4), or others (n = 6). The most commonly reported anesthetic techniques were asleep-awake-asleep protocols using propofol, remifentanil or fentanyl, a local scalp nerve block, and with or without dexmedetomidine. CONCLUSIONS: The findings of this systematic review suggest the tolerability and safety of ACs in the pediatric population. Although pediatric intracranial pathologies pose etiologies that certainly may benefit from AC, there is a need for surgeons and anesthesiologists to perform individualized risk-benefit analyses due to the risks associated with awake procedures in children. Age-specific, standardized guidelines for preoperative planning, intraoperative mapping, monitoring tasks, and anesthesia protocols will help to continue minimizing complications, while improving tolerability, and streamlining workflow in the treatment of this patient population.

Differences in Perioperative Management of Patients Undergoing Complex Spine Surgery: A Global Perspective.

BACKGROUND: The aim of this survey was to understand institutional spine surgery practices and their concordance with published best practices/recommendations. METHODS: Using a global internet-based survey examining perioperative spine surgery practice, reported institutional spine pathway elements (n=139) were compared with the level of evidence published in guideline recommendations. The concordance of clinical practice with guidelines was categorized as poor (≤20%), fair (21%-40%), moderate (41%-60%), good (61%-80%), or very good (81%-100%). RESULTS: Seventy-two of 409 (17.6%) institutional contacts started the survey, of which 31 (7.6%) completed the survey. Six (19.4%) of the completed surveys were from respondents in low/middle-income countries, and 25 (80.6%) were from respondents in high-income countries. Forty-one incomplete surveys were not included in the final analysis, as most were less than 40% complete. Five of 139 (3.6%) reported elements had very good concordance for the entire cohort; hospitals with spine surgery pathways reported 18 elements with very good concordance, whereas institutions without spine surgery pathways reported only 1 element with very good concordance. Reported spine pathways included between 7 and 47 separate pathway elements. There were 87 unique elements in the reviewed pathways. Only 3 of 87 (3.4%) elements with high-quality evidence demonstrated very good practice concordance. CONCLUSIONS: This global survey-based study identified practice variation and low adoption rates of high-quality evidence in the care of patients undergoing complex spine surgery.

Percutaneous endoscopic gastrostomy in amyotrophic lateral sclerosis: outcomes of a dedicated anesthesia and surgery protocol.

BACKGROUND: Patients requiring percutaneous endoscopic gastrostomy (PEG) for amyotrophic lateral sclerosis (ALS) related dysphagia represent a clinical challenge. Diminished pulmonary function and aspiration risks can lead to anesthesia-related complications, and gastric displacement from hemidiaphragm elevation may preclude safe gastric access. This study reports the efficacy and outcomes of a dedicated anesthesia/surgery management protocol for ALS patients undergoing PEG. METHODS: In 2013, a PEG placement protocol for ALS patients was developed emphasizing efficient pre-operative evaluation, rapidly metabolized anesthetic agents, and minimization of opioid use. Outcomes were analyzed retrospectively. Preoperative weight loss, pulmonary function tests, total analgesia, procedural time, and 90-day morbidity and mortality were recorded. RESULTS: From 2013-2019, 67 ALS patients (mean age 65.3 years, 52.2% female) received a PEG under the protocol. Mean percentage weight loss 6 months before PEG was 9.3 ± 5.1% with 38.8% of patients meeting criteria for severe malnutrition. Mean anesthesia time (propofol induction to anesthesia emergence) was 34.5 ± 10.8 min and mean operative time (endoscope insertion to dressing placement) was 16.4 ± 8.2 min. Regional anesthesia with liposomal bupivacaine was performed in 76.1%. All attempts at PEG placement were successful. With a mean follow-up of 6.1 ± 6.8 months, all PEGs were functional and there were no surgical site complications. Thirty-day readmission rate was 7.0% and 90-day mortality was 22.4% (46.7% occurring within 30 days). Mean time from surgery to death was 8.8 ± 7.8 months. CONCLUSIONS: Protocols for optimizing PEG may help overcome challenges present in the ALS patient population. Despite patient comorbidities, protocol implementation and dedicated team members resulted in a high procedural success rate and low complication rate. Further study is warranted to optimize the timing of PEG placement in relation to ALS disease progression and determine the utility of regional anesthesia during PEG placement.

Risk Factors Associated with ICU-Specific Care in Patients Undergoing Endovascular Treatment of Unruptured Intracranial Aneurysms.

BACKGROUND: Multiple studies suggest routine postoperative intensive care unit (ICUs) stays in presumed high-risk neurosurgical procedures may be unnecessary. Our objective was to evaluate the risk factors associated with ICU-specific needs in patients undergoing elective endovascular treatment of unruptured intracranial aneurysms. METHODS: A retrospective review of consecutive patients undergoing elective endovascular treatment of unruptured aneurysms was performed between January 2010 and January 2020 in a single academic medical center. Patient demographic information, aneurysm and treatment characteristics, intraoperative and postoperative complications, as well as ICU-specific needs, were abstracted. The primary outcome was ICU-specific needs. RESULTS: A total of 382 patient encounters in 344 unique patients were abstracted. 13.6% (52 of 382) of patient encounters had an ICU-specific need. Multivariate analysis revealed that age [adjusted odds ratio (OR) 1.04, 95% confidence interval (CI) 1.01-1.07, p = 0.03], procedure duration greater 200 min (adjusted OR 2.75, 95% CI 1.34-5.88, p = 0.007), and any intraoperative complication (adjusted OR 20.41, CI 7.97-56.57, p < 0.001) were independent predictors of postoperative ICU-specific needs. The majority of ICU-specific needs (94%, 49 of 52) occurred within 6 h of surgery. CONCLUSIONS: Our results show that age, procedure duration greater than or equal to 200 min, and intraoperative complication were independent predictors of postoperative ICU-specific needs in patients presenting for elective endovascular treatment of unruptured intracranial aneurysms. The majority of ICU-specific needs and associated complications occurred in the immediate postoperative period. This data can be used to help decide the appropriate postoperative level of care in this patient population.

Perioperative Care of Patients Undergoing Major Complex Spinal Instrumentation Surgery: Clinical Practice Guidelines From the Society for Neuroscience in Anesthesiology and Critical Care.

Evidence-based standardization of the perioperative management of patients undergoing complex spine surgery can improve outcomes such as enhanced patient satisfaction, reduced intensive care and hospital length of stay, and reduced costs. The Society for Neuroscience in Anesthesiology and Critical Care (SNACC) tasked an expert group to review existing evidence and generate recommendations for the perioperative management of patients undergoing complex spine surgery, defined as surgery on 2 or more thoracic and/or lumbar spine levels. Institutional clinical management protocols can be constructed based on the elements included in these clinical practice guidelines, and the evidence presented.

A Randomized Trial of Complications of Peripherally and Centrally Inserted Central Lines in the Neuro-Intensive Care Unit: Results of the NSPVC Trial.

OBJECTIVE: The objective of this study was to compare the relative number of complications from peripherally inserted central venous catheters (PICC) and centrally inserted central venous catheters (CVC) in the neuroscience intensive care unit (NSICU). METHODS: This study was carried out in a 32-bed NSICU in a large academic hospital in the USA from July 2015 until January 2017. Patients admitted requiring central venous access were randomly assigned to have a PICC or CVC inserted. Complications were recorded and compared. The primary outcome was all complications as well as combined numbers of large vein thrombosis, central-line-associated blood stream infections, and insertional trauma. Outcomes were compared using the Fisher's exact test, logistic regression, or unpaired T tests, as appropriate. RESULTS: One hundred and fifty-two patients were enrolled; 72 were randomized to the PICC arm and 80 to the CVC arm. There were no crossovers, withdrawals, nor losses to follow-up. The study was stopped at the second pre-planned interim analysis for futility. The combined number of large vein thrombosis, central-line-associated blood stream infection, and insertional trauma was 4/72 in the PICC arm and 1/80 in the CVC group (OR 4.6 (95% CI 0.5-42.6) p = 0.14). The number of all complications in the PICC arm was 14/72 compared to 10/80 in the CVC arm (OR 1.7 (95% CI 0.7-4.1) p = 0.24). CONCLUSIONS: PICCs and CVCs have similar numbers of complications when placed in patients admitted to the NSICU.

A Comprehensive NGS Data Analysis of Differentially Regulated miRNAs, piRNAs, lncRNAs and sn/snoRNAs in Triple Negative Breast Cancer.

Cancer is the second leading cause of death in the United States and is a major public health concern worldwide. Basic, clinical and epidemiological research is leading to improved cancer detection, prevention, and outcomes. Recent technological advances have allowed unbiased and comprehensive screening of genome-wide gene expression. Small non-coding RNAs (sncRNAs) have been shown to play an important role in biological processes and could serve as a diagnostic, prognostic and therapeutic biomarker for specific diseases. Recent findings have begun to reveal and enhance our understanding of the complex architecture of sncRNA expression including miRNAs, piRNAs, lncRNAs, sn/snoRNAs and their relationships with biological systems. We used publicly available small RNA sequencing data that was derived from 24 triple negative breast cancers (TNBC) and 14 adjacent normal tissue samples to remap various types of sncRNAs. We found a total of 55 miRNAs were aberrantly expressed (p<0.005) in TNBC samples (8 miRNAs upregulated; 47 downregulated) compared to adjacent normal tissues whereas the original study reported only 25 novel miRs. In this study, we used pathway analysis of differentially expressed miRNAs which revealed TGF-beta signaling pathways to be profoundly affected in the TNBC samples. Furthermore, our comprehensive re-mapping strategy allowed us to discover a number of other differentially expressed sncRNAs including piRNAs, lncRNAs, sn/snoRNAs, rRNAs, miscRNAs and nonsense-mediated decay RNAs. We believe that our sncRNA analysis workflow is extremely comprehensive and suitable for discovery of novel sncRNAs changes, which may lead to the development of innovative diagnostic and therapeutic tools for TNBC.

Exploration of small RNA-seq data for small non-coding RNAs in Human Colorectal Cancer.

Background: Improved healthcare and recent breakthroughs in technology have substantially reduced cancer mortality rates worldwide. Recent advancements in next-generation sequencing (NGS) have allowed genomic analysis of the human transcriptome. Now, using NGS we can further look into small non-coding regions of RNAs (sncRNAs) such as microRNAs (miRNAs), Piwi-interacting-RNAs (piRNAs), long non-coding RNAs (lncRNAs), and small nuclear/nucleolar RNAs (sn/snoRNAs) among others. Recent studies looking at sncRNAs indicate their role in important biological processes such as cancer progression and predict their role as biomarkers for disease diagnosis, prognosis, and therapy. Results: In the present study, we data mined publically available small RNA sequencing data from colorectal tissue samples of eight matched patients (benign, tumor, and metastasis) and remapped the data for various small RNA annotations. We identified aberrant expression of 13 miRNAs in tumor and metastasis specimens [tumor vs benign group (19 miRNAs) and metastasis vs benign group (38 miRNAs)] of which five were upregulated, and eight were downregulated, during disease progression. Pathway analysis of aberrantly expressed miRNAs showed that the majority of miRNAs involved in colon cancer were also involved in other cancers. Analysis of piRNAs revealed six to be over-expressed in the tumor vs benign cohort and 24 in the metastasis vs benign group. Only two piRNAs were shared between the two cohorts. Examining other types of small RNAs [sn/snoRNAs, mt_rRNA, miscRNA, nonsense mediated decay (NMD), and rRNAs] identified 15 sncRNAs in the tumor vs benign group and 104 in the metastasis vs benign group, with only four others being commonly expressed. Conclusion: In summary, our comprehensive analysis on publicly available small RNA-seq data identified multiple differentially expressed sncRNAs during colorectal cancer progression at different stages compared to normal colon tissue. We speculate that deciphering and validating the roles of sncRNAs may prove useful in colorectal cancer prognosis, diagnosis, and therapy.

Topical vanadate enhances the repair of median laparotomy incisions.

BACKGROUND: There are over two million laparotomies performed in the United States each year with an incisional hernia rate between 2% and 11%. A total of 100,000 ventral hernia repairs are undertaken each year with recurrences as high as 50%. MATERIALS AND METHODS: Full thickness midline fascia incisions from the xiphoid to the pubic symphysis were made in rats. The fascia and/or muscular layer was sutured closed and a gel with 300 µM of sodium orthovanadate or saline was placed over the suture line with the skin closed over it. On day 10, 1-cm strips from the superior, middle, and inferior regions of the abdominal wall were tested for breaking strength and processed for histology. RESULTS: The mean wound breaking strength of vanadate-treated wounds was 18.6 ± 2.7 N compared with 9.4 ± 3.6 N for controls (P < 0.0001). Similar quantities of granulation tissue were deposited in treated and control wounds. Fine green birefringence patterns, characteristic of immature connective tissue, were seen in control samples viewed with polarized light. In contrast, vanadate-treated wounds showed thick yellow-orange birefringence patterns characteristics of more mature connective tissue. Using α-smooth muscle actin immunostaining, myofibroblasts were prominent in control incisions, but few were identified in vanadate-treated incisions. CONCLUSIONS: In rat laparotomy wounds, a single application of vanadate increases wound breaking strength, through enhanced connective tissue organization. These combined data suggest topical application of vanadate immediately after fascial closure will increase wound strength, possibly reducing hernia recurrences in the repaired abdominal wall.

The evolution of perioperative transfusion testing and blood ordering.

The evolution of modern anesthesia and surgical practices has been accompanied by enhanced supportive procedures in blood banking and transfusion medicine. There is increased focus on the preparation and the use of blood components including, but not limited to, preventing unnecessary type and screen/crossmatch orders, decreasing the time required to provide compatible red blood cells (RBCs), and reducing the waste of limited blood and personnel resources. The aim of this review is to help the anesthesiologist and surgical staff identify patients at highest risk for surgical bleeding. In addition, this review examines how anesthesia and transfusion medicine can efficiently and safely allocate blood components for surgical patients who require transfusions. The following databases were searched: PubMed, EMBASE, Google Scholar, and the Cochrane Library from January 1970 through March 2014. Subsequent reference searches of retrieved articles were also assessed. Several innovations have drastically changed the procedures by which blood is ordered, inventoried, and the speed in which blood is delivered for patient care. Before entering an operating room, patient blood management provides guidance to clinicians about when and how to treat preoperative anemia and intra- and postoperative strategies to limit the patient's exposure to blood components. Timely updates of the recommendations for blood orders (maximum surgical blood ordering schedule) have enhanced preoperative decision making regarding the appropriateness of the type and screen versus the type and crossmatch order. The updated maximum surgical blood ordering schedule reflects modern practices, such as laparoscopy, improved surgical techniques, and use of hemostatic agents resulting in a more streamlined process for ordering and obtaining RBCs. The electronic (computer) crossmatch and electronic remote blood issue have also dramatically reduced the amount of time required to obtain crossmatch-compatible RBCs when compared with the more traditional serologic crossmatch methods. These changes in blood banking methods have resulted in more efficient delivery of blood to surgical patients.

Thymosin ß4 affecting the cytoskeleton organization of the myofibroblasts.

In previous studies, granulation tissue from subcutaneous sponge implants in rats receiving thymosin ß4, a 43-amino acid actin-binding protein that advances wound repair, produced the unexpected absence of myofibroblast populations, along with uniform organized collagen fibers within the newly deposited connective tissue matrix. This result raised the question of whether the Tß4 effect on blocking fibroblasts transformation into myofibroblasts a direct or indirect one. We report here work in progress to address this question. When human dermal fibroblasts are plated at low density, upon reaching confluence, they all express α smooth muscle actin (αSMA) within their cytoplasmic stress fibers, morphologically defining them as myofibroblasts. Treating low-density plated fibroblasts with Tß4 prevents their expression of αSMA, as well as the generation an uneven distribution of microtubules within the cytoplasm. The speculation is that Tß4 disruption of the distribution of microtubules alters the TGF-ß-Smad signaling pathway, thus blocking fibroblast transformation into myofibroblasts.

Demonstrating collagen tendon fibril segments involvement in intrinsic tendon repair.

Severed tendons can undergo regenerative healing, intrinsic tendon repair. Fibrillogenesis of chick tendon involves "collagen fibril segments" (CFS), which are the building blocks of collagen fibers that make up tendon fascicles. The CFS are 10.5 micron in length, composed of tropocollagen monomers arranged in parallel arrays. Rather than incorporating single tropocollagen molecules into growing collagen fibers, incorporating large CFS units is the mechanism for generating collagen fibers. Is intrinsic tendon repair through the reestablishment of tendon embryogenesis? Gentamicin treated 10-day-old chick embryo tendons released CFS were fluorescently tagged with Rhodamine (Rh). Organ cultured severed 14-day-old embryo tendon explants received Rh tagged CFS. At day 4 auto fluorescent tagged CFS were identified at the severed tendon ends by fluorescent microscopy. Accumulation of fluorescent tagged CFS was exclusively localized to the severed ends of tendon explants. Parallels between collagen fiber growth during embryonic fibrillogenesis and tendon repair reveal CFS incorporation is responsible for collagen fibers growth. CFS incorporation into frayed collagen fibers from severed tendons is the proposed mechanism for intrinsic tendon repair, which is an example of regenerative repair.

Increased post-operative complications with methylene blue versus lymphazurin in sentinel lymph node biopsies for skin cancers.

BACKGROUND: Sentinel lymph node biopsy (SNLB) is the standard of care in staging of melanoma and other skin cancers. Early studies used lymphazurin (LZ) for SLNB. A national shortage of LZ promoted methylene blue (MB) as an alternate stain. OBJECTIVE: This study compares complication rates between LZ and MB in SLNB patients, and the reliability dyes in locating sentinel lymph nodes. METHODS: Charts were reviewed for patients who underwent SLNB for skin cancers between September 2006 and November 2008 at Penn State Hershey Medical Center. The type and quantity of dye, the presence of blue stained sentinel nodes, and any complications were recorded. RESULTS: Ninety-three patients underwent SLNB (46 LZ, 47 MB). The amount of dye used was similar (avg. 0.93 ml LZ, 1.24 ml MB). The complication rate of LZ was 8.7%, and MB was 25.5%. There was significantly more (P = 0.003) skin graft complications in the MB patients (6/12) versus LZ (0/15). CONCLUSIONS: There is a higher rate of complications with MB, especially with skin grafting. The reported risk of anaphylaxis with LZ has not been reported in volumes <2 ml. The sentinel lymph node identification rate is historically similar between dyes, and in this study was noted to be higher with LZ.

Thymosin beta4 enhances repair by organizing connective tissue and preventing the appearance of myofibroblasts.

Incisional wounds in rats treated locally with thymosin beta4 (Tbeta4) healed with minimal scaring and without loss in wound breaking strength. Treated wounds were significantly narrower in width. Polarized light microscopy treated wounds had superior organized collagen fibers, displaying a red birefringence, which is consistent with mature connective tissue. Control incisions had randomly organized collagen fibers, displaying green birefringence that is consistent with immature connective tissue. Immunohistology treated wounds had few myofibroblasts and fibroblasts with alpha smooth muscle actin (SMA) stained stress fibers. Polyvinyl alcohol sponge implants placed in subcutaneous pockets received either carrier or 100 microg of Tbeta4 on days 2, 3, and 4. On day 14, treated implants revealed longer, thicker collagen fiber bundles with intense yellow-red birefringence by polarized light microscopy. In controls, fine, thin collagen fiber bundles were arranged in random arrays with predominantly green birefringence. Controls contained mostly myofibroblasts, while few myofibroblasts appeared in Tbeta4 treated implants. Electron microscopy confirmed both cell types and the degree of collagen fiber bundle organization. Our results demonstrate that Tbeta4 treated wounds appear to mature earlier and heal with minimal scaring.

Temporal association of large granular lymphocytosis, neutropenia, proviral load, and FasL mRNA in cats with acute feline immunodeficiency virus infection.

During acute feline immunodeficiency virus-C(PGammar) (FIV-C-PG) infection, we observed that cats develop large granular lymphocyte (LGL) lymphocytosis concurrent with a marked neutropenia that is temporally associated with the rise and fall of FIV-C-PG proviral loads. LGLs, generally considered to be analogous to natural killer (NK) cells, can also be highly cytolytic CD8/CD57 T cells. Neutropenia has been reported during acute human immunodeficiency virus (HIV-1) infection, but there is a paucity of information describing the pathogenesis of this condition. During HIV-1 infection, LGLs have been shown to be both CD16(+) NK cells and CD8(+)/CD57(+) T cells, but an association with neutropenia has not been described. However, neutropenia with concurrent LGL lymphocytosis has been demonstrated in both LGL leukemia and common variable immunodeficiency syndrome in people, and in both syndromes, an increase in soluble Fas ligand (FasL) has been associated with neutrophil apoptosis leading to neutropenia. Flow cytometric analysis demonstrated increases in CD56 and CD8 peripheral blood cell surface expression during acute FIV-C-PG infection. Expression of FasL mRNA was increased at the same time points as these peripheral hematologic abnormalities, and also decreased as FIV-C-PG proviral load reached set point. We describe an interesting temporal association between innate immune responses and viral load during acute FIV-C-PG infection, which has similarities to HIV-1 infection and other immune dyscrasias of people, and which may contribute to the neutropenia and LGL lymphocytosis during FIV-C-PG infection.

Culture and comparison of feline myeloid dendritic cells vs macrophages.

To gain insight into the role of dendritic cells (DCs) in feline immunodeficiency virus (FIV) infection and immunity, methods were developed to culture feline myeloid DCs from CD14(+) monocytes with a combination of human recombinant granulocyte-macrophage colony-stimulating factor (hrGM-CSF) and interleukin-4 (hrIL-4). These cells were compared with feline macrophages cultured in the presence of hrGM-CSF. As with DCs in other species, feline DCs showed uniformly high MHC class II expression, moderate B7.1 expression, potent induction of the allogeneic mixed leucocyte reaction (MLR), and moderate uptake of fluorescein isothiocyanate-dextran (FITC-DX) in the endocytic assay. In comparison with feline macrophages, DCs showed higher expression of MHC class II, similar expression of B7.1, CD14, CXCR4 and CD1a, and lower expression of CD11b. When placed on alcian blue-coated glass slides, DCs differed from macrophages in showing a greater tendency to spread out; they also had characteristic fine cytoplasmic processes instead of the broader pseudopodia of macrophages. Basal IL-12 mRNA expression and FITC-DX uptake were greater in DCs than in macrophages. Unlike feline DCs, feline macrophages exhibited a dose-dependent suppressive effect in the MLR. Feline DCs propagated in vitro should prove useful in the development of DC-mediated vaccination and therapy for infectious and neoplastic feline diseases. Additionally, macrophages cultured with GM-CSF provide a potential means of studying the mechanism of immunosuppression in cats.

Hemochromatosis secondary to repeated blood transfusions in a dog.

Hemochromatosis was presumptively diagnosed using cytologic examination of liver tissue from an aged male Miniature Schnauzer. The dog was presented after receiving whole blood transfusion every 6-8 weeks for 3 years to treat pure red cell aplasia. The cytologic specimen contained clusters of hepatocytes with abundant intracytoplasmic gold-yellow pigment granules and clumps of extracellular, green-black, globular pigment, both interpreted to be hemosiderin. Histologic sections of liver revealed hepatocellular degeneration with bridging portal fibrosis, lobular atrophy, biliary hyperplasia, and diffuse, severe hemosiderin accumulation. Serum iron and ferritin levels, and dry-weight iron concentrations of liver, heart, and kidneys were markedly increased. Hemosiderin accumulation was confirmed in hepatocytes of cytologic and histologic specimens using Perl's Prussian blue staining. This report is the first description of transfusional hemochromatosis in a dog and is the first to describe its cytologic appearance in a veterinary patient.