Descending Control of Nociception Poorly Predicts the Development of Persistent Postsurgical Pain-like Behavior in Consomic Dahl S Rat Strains.

BACKGROUND: Chronic postsurgical pain is a poorly recognized outcome of surgery where patients experience pain long after healing from the surgical insult. Descending control of nociception, a phenomenon whereby application of a strong nociceptive stimulus to one part of the body of animals inhibits pain in remote body regions, offers one strategy to identify a propensity to develop chronic postsurgical pain-like behavior. Here, consomic rat panel was used to test the hypothesis that pain persistence is mechanistically linked to ineffective descending control of nociception. METHODS: Male and female Brown Norway, Dahl S, and eight consomic strains (SS-xBN) were used to determine the presence of chronic postsurgical pain-like behaviors by using paw-withdrawal threshold evaluation (von Frey method) in the area adjacent to a hind paw plantar incision. Descending control of nociception was assessed by measuring hind paw-withdrawal thresholds (Randall-Selitto method) after capsaicin (125 µg) injection into a forepaw. Consomic rats were developed by introgressing individual Brown Norway chromosomes on the Dahl S rat genetic background, as Dahl S rats lack preoperative descending control of nociception. RESULTS: Substitution of several chromosomes from the "pain-resistant" Brown Norway to the "pain-prone" Dahl S/Medical College of Wisconsin reduced mechanical nociceptive sensitivity and increased endogenous pain modulation capacity by differing degrees. Statistical modeling of these data revealed that descending control of nociception is a poor general predictor of the propensity to develop chronic postsurgical pain-like behavior (poor fit for model 1). However, a significant strain-by-descending control of nociception interaction was revealed (model 3, -2*log likelihood; 550.668, -2ll change; 18.093, P = 0.034) with SS-13BN and SS-15BN strains showing a negative descending control of nociception relationship with chronic postsurgical pain-like behavior. CONCLUSIONS: Descending control of nociception poorly predicted which rat strains developed chronic postsurgical pain-like behavior despite controlling for genetic, environmental, and sex differences. Two consomic strains that mimic clinical chronic postsurgical pain criteria and display a strong negative correlation with descending control of nociception were identified, offering novel candidates for future experiments exploring mechanisms that lead to chronic postsurgical pain.

Bile duct obstruction associated with pancreatitis in 46 dogs.

BACKGROUND: Pancreatitis is a common cause of extrahepatic bile duct obstruction (EHBDO) in dogs. Information describing the clinical course of dogs with pancreatitis associated bile duct obstruction (PABDO) is limited. OBJECTIVES: To describe the clinical course of PABDO in dogs and determine if presumed markers of disease severity are predictors of survival. ANIMALS: Forty-six client-owned dogs with PABDO. METHODS: A retrospective review of medical records from dogs diagnosed with PABDO was performed. Data, including clinical signs and biochemical changes, were collected 6 times throughout the course of disease. Outcome was defined as either survival (discharge from the hospital) or death. RESULTS: Thirty-three (79%) out of 42 dogs with PABDO survived. Thirty-one (94%) of the 33 dogs that survived received medical management alone. Time from onset of clinical signs to initial documented increase in serum bilirubin concentration, peak bilirubin elevation, and initial decline in serum bilirubin concentration were 7 (median), 8, and 15 days, respectively. The median number of days from onset of clinical signs to outcome date was 13. Clinical signs of fever, vomiting, and anorexia were decreased in frequency from the onset of clinical signs to the time of peak bilirubin. Median bile duct dilatation at the time of ultrasonographic diagnosis of PABDO and peak bilirubin were not different between survivors (7.6 mm, 11.7 mg/dL) and nonsurvivors (6 mm, 10.6 mg/dL, P = .12, P = .8). CONCLUSIONS: Dogs with PABDO often have a prolonged course of illness and improve clinically despite biochemical evidence of progression of EHBDO.

Hemophagocytic syndrome in a cat.

CASE SUMMARY: A 12-year-old male castrated domestic shorthair cat was evaluated for a 10 month history of weight loss. Thin body condition and a grade II/VI systolic parasternal heart murmur was noted during examination. Moderate-to-severe anemia and intermittent thrombocytopenia were identified on serial complete blood counts. Antibodies against feline immunodeficiency virus (FIV) were detected, but vaccination for FIV occurred previously. Echocardiography revealed biatrial and biventricular enlargement, left ventricular hypertrophy and pericardial effusion. Splenomegaly was present on abdominal ultrasound and cytological evaluation revealed macrophagic infiltration with erythrophagocytosis. Cytological evaluation of the bone marrow revealed similar findings. Histopathology of the spleen confirmed hemophagocytosis with no evidence of malignancy. A presumptive diagnosis of hemophagocytic syndrome was made. PCR testing for FIV on the splenic tissue was negative. The cat was treated with lomustine. Disease progression occurred approximately 6 months after diagnosis and the cat was euthanized. RELEVANCE AND NOVEL INFORMATION: To our knowledge, this is one of the few reports describing the diagnosis of hemophagocytic syndrome in a cat.

Estrogen modulation properties of mangiferin and quercetin and the mangiferin metabolite norathyriol.

Mango fruit contain many bioactive compounds, some of which are transcription factor regulators. Estrogen receptor alpha (ERα) and beta (ERß) are two regulators of gene transcription that are important in a variety of physiological processes and also in diseases including breast cancer. We examined the ability of the mango constituents quercetin, mangiferin, and the aglycone form of mangiferin, norathyriol, to activate both isoforms of the estrogen receptor. Quercetin and norathyriol decreased the viability of MCF-7 breast cancer cells whereas mangiferin had no effect on MCF-7 cells. We also determined that quercetin and mangiferin selectively activated ERα whereas norathyriol activated both ERα and ERß. Despite quercetin, mangiferin and norathyriol having similar polyphenolic structural motifs, only norathyriol activated ERß, showing that bioactive agents in mangoes have very specific biological effects. Such specificity may be important given the often-opposing roles of ERα and ERß in breast cancer proliferation and other cellular processes.

Short duration electrical stimulation to enhance neurite outgrowth and maturation of adult neural stem progenitor cells.

New therapies are desperately needed for human central nervous system (CNS) regeneration to circumvent the lack of innate regenerative ability following traumatic injuries. Previously attempted therapies have been stymied by barriers to CNS regeneration largely because of protective mechanisms such as the blood brain barrier, inhibitory molecules, and glial scar formation. The application of electric stimulation (ES) has shown promise for enhancing peripheral nervous system regeneration, but is in its infancy in CNS regeneration. The objective of this study is to better understand how short duration ES can be harnessed to direct adult neural stem progenitor cell (NSPC) neurogenesis, neurite extension, and maturation. Herein, NSPCs were exposed to physiological levels of electrical stimulation of 0.53 or 1.83 V/m (applied power supply setting of 1.2 and 2.5 V) of direct current (DC) for 10 min/days for 2 days with a total differentiation time of 3 days. Culturing conditions consisted of either mitogenic growth factors or the neuronal differentiation factor interferon-γ (IFN-γ). Stimulated NSPCs showed lengths that were over five times longer than unstimulated controls (112.0 ± 88.8 µm at 0.53 V/m vs. 21.3 ± 8.5 µm for 0 V/m with IFN-γ) with the longest neurites reaching up to 600 µm. Additionally, ES resulted in mature neuronal morphologies and signs of differentiation through positive ßIII tubulin, neuronal nuclei (NeuN), and better organized filamentous-actin (f-actin) staining with growth cone formation. Additionally, the neurites and soma of stimulated NSPCs showed increases in intracellular Ca(2+) during stimulation, signifying the presence of functional neurons capable of electrical conductance and communication with other cells. Our study demonstrates that short stimulation times (10 min/ day) result in significant neurite extension of stem cells in a quick time frame (3 days). This ES modality is potentially advantageous for promoting axon re-growth at an injury site using delivered adult stem cells; however, significant work still remains to understand both the delivery approach of cells as well as ES application in vivo.

Clinical practice breastfeeding recommendations for primary care: applying a tri-core breastfeeding conceptual model.

Promotional practice efforts are needed in primary care to support and foster breastfeeding as the first and natural choice of nutrition for all infants regardless of race, ethnicity, educational, or income demographics in the United States. Societal awareness is increasing with regard to the significant protective qualities that human milk bestows upon public health. An estimated 75% of American mothers attempt to breastfeed, but according to the Centers for Disease Control and Prevention, just 13% are able to exclusively breastfeed by 6 months. Early identification of lactation issues is crucial to establishing and sustaining breastfeeding for the first 6 to 12 months of the child's life and beyond. We propose a set of primary care guidelines, applying a Tri-Core Model approach, to promote and foster breastfeeding efforts in the postpartum period. Breastfeeding promotion is a fundamental public health endeavor, and pediatric nurse practitioners and other advanced practice registered nurses (APRNs) are uniquely qualified to become specialists and experts in lactation care and management. Lactation support, which should be an integral facet of an APRN's practice and education, will aid in improving national breastfeeding rates and patient care outcomes. Application of the Tri-Core Model approach will help APRNs develop and implement evidence-based practice efforts that incorporate the mother-baby dyad and other multiprofessionals who are vested in successful breastfeeding outcomes. The goal of pediatric health care is provide safe and effective health care to all infants, children, and adolescents, and lactation care is an integral and crucial component of this effort.

Immobilized ECM molecules and the effects of concentration and surface type on the control of NSC differentiation.

New developments in growth factor and pharmaceutical control of cells for neural regenerative strategies have built a need for high throughput assays to conveniently screen these treatments in vitro before moving to more complex experiments. Towards this application, we have studied an easy and highly reproducible culture regime with a renewable cell source for central nervous system (CNS) strategies. Adult neural stem cells (NSCs) derived from the CNS are attractive for use in screening assay because they are easily expanded and can differentiate into all major CNS cell types. NSCs were cultured on glass alone or methacrylamide chitosan (MAC) hydrogel coated glass substrates, immobilized with extracellular matrix (ECM) proteins collagen and laminin at varying densities. Proteins were also adsorbed on the surfaces as a control. We found that adsorbed protein on hydrogel coated glass resulted in the highest cell densities after 8 d, over twice the density of immobilized groups or adsorbed protein on glass. No significant differences were observed between collagen, laminin, or both proteins together regarding cell differentiation (p > 0.05); however, the morphological spreading and branching of differentiated NSC processes was enhanced on MAC substrates with covalently immobilized laminin protein. The results of this study suggest that a soft MAC hydrogel surface with adsorbed protein would be most desirable for specifying neuronal differentiation of large numbers of stem cells due to the high cellularities they supported.

Intracranial hyperthermia through local photothermal heating with a fiberoptic microneedle device.

BACKGROUND AND OBJECTIVES: The fiberoptic microneedle device (FMD) seeks to leverage advantages of both laser-induced thermal therapy (LITT) and convection-enhanced delivery (CED) to increase volumetric dispersal of locally infused chemotherapeutics through sub-lethal photothermal heat generation. This study focused on determination of photothermal damage thresholds with 1,064 nm light delivered through the FMD into in vivo rat models. MATERIALS AND METHODS: FMDs capable of co-delivering laser energy and fluid agents were fabricated through a novel off-center splicing technique involving fusion of a multimode fiberoptic to light-guiding capillary tubing. FMDs were positioned at a depth of 2.5 mm within the cerebrum of male rats with fluoroptic temperature probes placed within 1 mm of the FMD tip. Irradiation (without fluid infusion) was conducted at laser powers of 0 (sham), 100, 200, 500, or 750 mW. Evans blue-serum albumin conjugated complex solution (EBA) and laser energy co-delivery were performed in a second set of preliminary experiments. RESULTS: Maximum, steady-state temperatures of 38.7 ± 1.6 and 42.0 ± 0.9 °C were measured for the 100 and 200 mW experimental groups, respectively. Histological investigation demonstrated needle insertion damage alone for sham and 100 mW irradiations. Photothermal damage was detected at 200 mW, although observable thermal damage was limited to a small penumbra of cerebral cortical microcavitation and necrosis that immediately surrounded the region of FMD insertion. Co-delivery of EBA and laser energy presented increased volumetric dispersal relative to infusion-only controls. CONCLUSION: Fluoroptic temperature sensing and histopathological assessments demonstrated that a laser power of 100 mW results in sub-lethal brain hyperthermia, and the optimum, sub-lethal target energy range is likely 100-200 mW. The preliminary FMD-CED experiments confirmed the feasibility of augmenting fluid dispersal using slight photothermal heat generation, demonstrating the FMD's potential as a way to increase the efficacy of CED in treating MG.

Bioactivity of mango flesh and peel extracts on peroxisome proliferator-activated receptor γ [PPARγ] activation and MCF-7 cell proliferation: fraction and fruit variability.

Mangos are a source of bioactive compounds with potential health promoting activity. Biological activities associated with mango fractions were assessed in cell-based assays to develop effective extraction and fractionation methodologies and to define sources of variability. Two techniques were developed for extraction and fractionation of mango fruit peel and flesh. Liquid chromatography-mass spectrometry (LC-MS) was used to assess compositional differences between mango fractions in flesh extracts. Many of the extracts were effective in inhibiting the proliferation of human breast cancer cells in vitro. All fractions showed bioactivity in PPAR activation assays, but quantitative responses showed marked fruit-to-fruit variability, highlighting the need to bulk fruit prior to extraction for activity-guided fractionation of bioactive components. This study also suggests that combinations of diverse molecular components may be responsible for cell-level bioactivities from mango fractions, and that purification and activity profiling of individual components may be difficult to relate to whole fruit effects. Practical Application: Although the health benefits of fruits are strongly indicated from studies of diet and disease, it is not known what role individual fruit types can play, particularly for tropical fruits. This study shows that there is a diversity of potentially beneficial bioactivities within the flesh and peel of mango fruit, although fruit-to-fruit variation can be large. The results add to the evidence that the food approach of eating all components of fruits is likely to be more beneficial to health than consuming refined extracts, as the purification process would inevitably remove components with beneficial bioactivities.

Mango extracts and the mango component mangiferin promote endothelial cell migration.

This study tested the hypothesis that mango extracts contain bioactive molecules capable of modulating endothelial cell migration, an essential step in the formation of new blood vessels or angiogenesis. The formation of new blood vessels is an important therapeutic target for diseases such as limb ischemia, coronary infarction or stroke. We examined the effect of mango peel and flesh extracts as well as the individual polyphenolic molecules, mangiferin and quercetin, on bovine aortic cell migration using a modified Boyden chamber assay. Our results show that mangiferin, and extracts rich in mangiferin, increase endothelial cell migration. The dose-effect relationship for various extracts further suggests that this action of mangiferin is modulated by other components present in the extracts. The promigratory effect of mango extracts or mangiferin was unrelated to an effect on cell proliferation, and did not involve a change in the production of matrix metalloprotease-2 or -9 by the endothelial cells. Taken together, these results suggest that mangiferin present in mango extracts may have health promoting effects in diseases related to the impaired formation of new blood vessels.

Weight and age as predictors for passing the infant car seat challenge.

OBJECTIVE: The American Academy of Pediatrics recommends observation of preterm and at-risk infants in their car seat before hospital discharge to screen for breathing problems. This observation period, which we refer to as the infant car seat challenge (ICSC), is used to determine readiness for travel in a car seat. Infants who fail the ICSC are recommended to travel in a car bed. Limited data exist to identify risk factors for failing the ICSC, and no guidelines are available to facilitate transition from car beds to car seats. The purpose of this study was to determine whether weight and age are predictors for passing the ICSC. METHODS: This retrospective study evaluated 43 infants referred to the Children's Hospital Boston Center for Healthy Infant Lung Development for a repeat ICSC after initial failure and 37 infants who passed or failed their initial ICSC at the Caritas Saint Elizabeth's Medical Center. Gender, birth weight, gestational age (GA), weight (ICSC weight), corrected GA, and chronological age at time of ICSC were extracted, and logistic regression analysis was performed. RESULTS: The average GA at birth of infants referred was 35 weeks 2 days (+/-2 weeks 3 days), and almost equal numbers of boys and girls were referred. A majority of infants passed their initial rechallenge (38 [88%] of 43). Infants who failed the repeat challenge were slightly smaller (3327 +/- 927 vs 3913 +/- 936 g) and younger at time of retesting (CGA 40 weeks 5 days vs 42 weeks 5 days; chronological age 39.2 vs 52.2 days). Neither weight nor age at initial or repeat ICSC predicted passing the ICSC. CONCLUSIONS: This study suggests that ICSC screenings remain the safest method for transitioning preterm infants from a car bed to a car seat.

Effects of the mango components mangiferin and quercetin and the putative mangiferin metabolite norathyriol on the transactivation of peroxisome proliferator-activated receptor isoforms.

Mangos are a source of bioactive compounds with potential health-promoting activity. This study evaluated the abilities of the mango components quercetin and mangiferin and the aglycone derivative of mangiferin, norathyriol, to modulate the transactivation of peroxisome proliferator-activated receptor isoforms (PPARs). PPARs are transcription factors important in many human diseases. Through the use of a gene reporter assay it was shown that quercetin inhibited the activation of all three isoforms of PPARs (PPARgamma IC(50) = 56.3 microM; PPARalpha IC(50) = 59.6 microM; PPARbeta IC(50) = 76.9 microM) as did norathyriol (PPARgamma IC(50) = 153.5 microM; PPARalpha IC(50) = 92.8 microM; PPARbeta IC(50) = 102.4 microM), whereas mangiferin did not inhibit the transactivation of any isoform. These findings suggest that mango components and metabolites may alter transcription and could contribute to positive health benefits via this or similar mechanisms.

Inhibition of glycosaminoglycan synthesis using rhodamine B in a mouse model of mucopolysaccharidosis type IIIA.

Reduction of an enzyme activity required for the lysosomal degradation of glycosaminoglycan (gag) chains will result in a mucopolysaccharidosis (MPS) disorder. Substrate deprivation therapy (SDT), a potential therapy option for MPS with residual enzyme activity, aims to reduce the synthesis of gag chains, the natural substrate for the deficient enzyme. Reduced substrate levels would balance the reduced level of enzyme in patient cells, resulting in normalized gag turnover. Rhodamine B, a nonspecific inhibitor, reduced gag synthesis in a range of normal and MPS cells and also decreased lysosomal storage of gag in MPS VI (72%) and MPS IIIA (60%) cells. Body weight gain of male MPS IIIA mice treated with 1 mg/kg rhodamine B was reduced compared with untreated MPS IIIA mice and was indistinguishable from that of normal mice. Liver size, total gag content, and lysosomal gag was reduced in treated MPS IIIA animals as was urinary gag excretion. Lysosomal gag content in the brain was also reduced by treatment. The alteration in MPS IIIA clinical pathology by rhodamine B, combined with the observation that treatment had no effect on the health of normal animals, demonstrates the potential for SDT in general as a therapy for MPS disorders.