Offspring behavioral outcomes following maternal allergic asthma in the IL-4-deficient mouse

Maternal allergic asthma (MAA) during pregnancy has been associated with increased risk of neurodevelopmental disorders in humans, and rodent studies have demonstrated that inducing a T helper-2-mediated allergic response during pregnancy leads to an offspring behavioral phenotype characterized by decreased social interaction and increased stereotypies. The interleukin (IL)-4 cytokine is hypothesized to mediate the neurobehavioral impact of MAA on offspring. Utilizing IL-4 knockout mice, this study assessed whether MAA without IL-4 signaling would still impart behavioral deficits. C57 and IL-4 knockout female mice were sensitized to ovalbumin, exposed to repeated MAA inductions, and their offspring performed social, cognitive, and motor tasks. Only C57 offspring of MAA dams displayed social and cognitive deficits, while IL-4 knockout mice showed altered motor activity compared with C57 mice. These findings highlight a key role for IL-4 signaling in MAA-induced behavioral deficits and more broadly in normal brain development.

Serum short chain fatty acids mediate hippocampal BDNF and correlate with decreasing neuroinflammation following high pectin fiber diet in mice

Introduction

Dietary components, such as prebiotic fiber, are known to impact brain chemistry via the gut-brain axis. In particular, short chain fatty acids (SCFAs) generated from excessive soluble fiber consumption are thought to impact neuroimmune signaling and brain function through increased production of neurotropic factors. Given reports that high dietary fiber intake is associated with increased mental health and improved quality of life scores, we set out to identify whether changes in SCFA levels as a result of a high soluble fiber diet mediate hippocampal neuroinflammation and brain derived neurotrophic factor (BDNF) in mice.

Methods

Adult male and female C57BL/6 mice were fed a 1-month high pectin fiber or cellulose-based control diet. Following 1 month of excessive pectin consumption, serum SCFAs were measured using gas chromatography-mass spectrometry (GC-MS) and hippocampal cytokines and BDNF were assessed via multiplex magnetic bead immunoassay.

Results

Pectin-based fiber diet increased circulating acetic acid in both sexes, with no effect on propionic or butyric acid. In the hippocampus, a high fiber diet decreased TNFa, IL-1ß, IL-6, and IFNγ and increased BDNF levels. Furthermore, increased SCFA levels were inversely correlated with neuroinflammation in the hippocampus, with acetic acid revealed as a strong mediator of increased BDNF production.

Conclusion

Collectively, these findings highlight the beneficial effects of fiber-induced molecular changes in a brain region known to influence mood- and cognition-related behaviors. Dietary composition should be considered when developing mental health management plans for men and women with an emphasis on increasing soluble fiber intake.

Maternal Allergic Asthma Induces Prenatal Neuroinflammation

Autism spectrum disorder (ASD) is a class of neurodevelopmental disorders characterized by impaired social interactions and communication skills and repetitive or stereotyped behaviors. Rates of ASD diagnosis continue to rise, with current estimates at 1 in 44 children in the US (Maenner 2021). Epidemiological studies have suggested a link between maternal allergic asthma and an increased likelihood of having a child diagnosed with ASD. However, a lack of robust laboratory models prevents mechanistic research from being carried out. We developed a novel mouse model of maternal asthma-allergy (MAA) and previously reported that offspring from these mothers exhibit behavioral deficits compared to controls. In addition, it was shown that epigenetic regulation of gene expression in microglia was altered in these offspring, including several autism candidate genes. To further elucidate if there is neuroinflammation in the fetus following MAA, we investigated how allergic asthma impacts the maternal environment and inflammatory markers in the placenta and fetal brain during gestation. Female C57Bl/6 mice were primed with ovalbumin (OVA) prior to allergic asthma induction during pregnancy by administering aerosolized ovalbumin or PBS control to pregnant dams at gestational days (GD)9.5, 12.5, and 17.5. Four hours after the final induction, placenta and fetal brains were collected and measured for changes in cytokines using a Luminex bead-based multiplex assay. Placental MAA tissue showed a decrease in interleukin (IL)-17 in male and female offspring. There was a sex-dependent decrease in female monocyte chemoattractant protein 1 (MCP-1). In male placentas, IL-4, C-X-C motif chemokine 10 (CXCL10)-also known as interferon γ-induced protein 10 kDa (IP-10)-and chemokine (C-C motif) ligand 5 (RANTES) were decreased. In fetal brains, elevated inflammatory cytokines were found in MAA offspring when compared to controls. Specifically, interferon-gamma (IFN-γ), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin 1α (IL-1α), IL-6, and tumor necrosis factor α (TNFα) were elevated in both males and females. In contrast, a decrease in the cytokine IL-9 was also observed. There were slight sex differences after OVA exposures. Male fetal brains showed elevated levels of macrophage inflammatory protein-2 (MIP-2), whereas female brains showed increased keratinocytes-derived chemokine (KC). In addition, IL-1𝛽 and IP-10 in male fetal brains were decreased. Together, these data indicate that repeated exposure to allergic asthma during pregnancy alters cytokine expression in the fetal environment in a sex-dependent way, resulting in homeostatic and neuroinflammatory alterations in the fetal brain.

Ten-week high fat and high sugar diets in mice alter gut-brain axis cytokines in a sex-dependent manner

Diets high in fat and sugar induce inflammation throughout the body, particularly along the gut-brain axis; however, the way these changes in immune signaling mediate one another remains unknown. We investigated cytokine changes in the brain and colon following prolonged high fat or sugar diet in female and male adult C57BL/6 mice. Ten weeks of high fat diet increased levels of TNFα, IL-1β, IL-6, IFNγ, and IL-10 in the female hippocampus and altered cytokines in the frontal cortex of both sexes. High sugar diet increased hippocampal cytokines and decreased cytokines in the diencephalon and frontal cortex. In the colon, high fat diet changed cytokine expression in both sexes, while high sugar diet only increased TNFα in males. Causal mediation analysis confirmed that colon IL-10 and IL-6 mediate high fat diet-induced neuroimmune changes in the female hippocampus and male frontal cortex. Additionally, high fat diet increased food consumption and weight gain in both sexes, while high sugar diet decreased male weight gain. These findings reveal a novel causal link between gut and brain inflammation specific to prolonged consumption of high fat, not high sugar, diet. Importantly, this work includes females which have been under-represented in diet research, and demonstrates that diet-induced neuroinflammation varies by brain region between sexes. Furthermore, our data suggest female brains are more vulnerable than males to inflammatory changes following excessive fat and sugar consumption, which may help explain the increased risk of inflammation-associated psychiatric conditions in women who eat a Western Diet rich in both dietary components.

Repeated allergic asthma in early versus late pregnancy differentially impacts offspring brain and behavior development

BACKGROUND

Stress during pregnancy and maternal inflammation are two common prenatal factors that impact offspring development. Asthma is the leading chronic condition complicating pregnancy and a common source of prenatal stress and inflammation.

OBJECTIVE

The goal of this study was to characterize the developmental impact of repeated allergic asthma inflammation during pregnancy on offspring behavioral outcomes and brain inflammation.

METHODS

Pregnant female C57BL/6 mice were sensitized with ovalbumin (OVA) or PBS vehicle control and then randomly assigned to receive daily aerosol exposures to the same OVA or PBS treatment during early, gestational days (GD) 2-GD9, or late pregnancy, GD10-GD17. Maternal sera were collected after the first and last aerosol induction regimen and measured for concentrations of corticosterone, anti-OVA IgE, and cytokine profiles. Juvenile male and female offspring were assessed for locomotor and social behaviors and later as adults assessed for anxiety-like, and marble burying behaviors using a series of behavioral tasks. Offspring brains were evaluated for region-specific differences in cytokine concentrations.

RESULTS

In early gestation, both PBS and OVA-exposed dams had similar serum corticosterone concentration at the start (GD2) and end (GD9) of daily aerosol inductions. Only OVA-exposed dams showed elevations in cytokines that imply a diverse and robust T helper cell-mediated immune response. Male offspring of early OVA-exposed dams showed decreases in open-arm exploration in the elevated plus maze and increased marble burying without concomitant changes in locomotor activity or social interactions. These behavioral deficits in early OVA-exposed male offspring were associated with lower concentrations of G-CSF, IL-4, IL-7, IFNγ, and TNFα in the hypothalamus. In late gestation, both PBS and OVA-exposed dams had increased corticosterone levels at the end of daily aerosol inductions (GD17) compared to at the start of inductions (GD10). Male offspring from both PBS and OVA-exposed dams in late gestation showed similar decreases in open arm exploration on the elevated plus maze compared to OVA male offspring exposed in early gestation. No behavioral differences were present in female offspring across all treatment groups. However, females of dams exposed to OVA during early gestation displayed similar reductions as males in hypothalamic G-CSF, IL-7, IL-4, and IFNγ.

DISCUSSION

The inflammatory responses from maternal allergic asthma in early gestation and resulting increases in anxiety-like behavior in males support a link between the timing of prenatal insults and sex-specific developmental outcomes. Moreover, the heightened stress responses in late gestation and concomitant dampened inflammatory response to allergic asthma suggest that interactions between the maternal immune and stress-response systems shape early life fetal programming.

Neuroinflammatory and Behavioral Outcomes Measured in Adult Offspring of Mice Exposed Prenatally to E-Cigarette Aerosols

BACKGROUND

In an effort to decrease the rates of smoking conventional tobacco cigarettes, electronic cigarettes (e-cigarettes) have been proposed as an effective smoking cessation tool. However, little is known about their toxicological impacts. This is concerning given that e-cigarette use is perceived as less harmful than conventional tobacco cigarettes during pregnancy for both the mother and fetus.

OBJECTIVE

The goal of this study was to test the neurodevelopmental consequences of maternal e-cigarette use on adult offspring behavior and neuroimmune outcomes.

METHODS

Pregnant female CD-1 mice were randomly assigned to one of three treatment groups (n=8-10 per group) and exposed daily to either filtered air, propylene glycol and vegetable glycerol (50:50 PG/VG vehicle), or to PG/VG with 16mg/mL nicotine (+Nic). Whole-body exposures were carried out for 3 h/d, 7 d/week, from gestational day (GD)0.5 until GD17.5. Adult male and female offspring (8 weeks old) were assessed across a battery of behavioral assessments followed by region-specific quantification of brain cytokines using multiplex immunoassays.

RESULTS

Adult offspring of both sexes exposed to +Nic exhibited elevated locomotor activity in the elevated plus maze and altered stress-coping strategies in the forced swim task. Moreover, male and female offspring exposed to PG/VG with and without nicotine had a 5.2% lower object discrimination score in the novel object recognition task. In addition to differences in offspring behavior, maternal e-cigarette exposure with nicotine led to a reduction in interleukin (IL)-4 and interferon-gamma (IFNγ) in the diencephalon, as well as lower levels of hippocampal IFNγ (females only). E-cigarette exposure without nicotine resulted in a 2-fold increase of IL-6 in the cerebellum.

DISCUSSION

These findings support previous adverse findings of e-cigarette exposure on neurodevelopment in a mouse model and provide substantial evidence of persistent adverse behavioral and neuroimmunological consequences to adult offspring following maternal e-cigarette exposure during pregnancy. https://doi.org/10.1289/EHP6067.

Perinatal exposure to concentrated ambient particulates results in autism-like behavioral deficits in adult mice

Exposure to fine ambient particulates (PM2.5) during gestation or neonatally has potent neurotoxic effects. While biological and behavioral data indicate a vulnerability to environmental pollutants across distinct neurodevelopmental windows, the behavioral consequences following exposure across the entire developmental period remain unknown. Moreover, several epidemiological studies support a link between developmental exposure to air pollution and an increased risk of later receiving a diagnosis of autism spectrum disorders (ASD), a neurodevelopmental disorder that persists throughout life. In the current study we sought to determine whether perinatal exposure to PM2.5 would reduce sociability and increase repetitive deficits in mice, two hallmark characteristics of ASD. Pregnant female B6C3F1 mice were exposed daily to concentrated ambient PM2.5 (CAPs) (135.8μg/m3) or filtered air (3.1μg/m3) throughout gestation followed by additional exposures to both dams and their litters from days 2-10 postpartum. Adult offspring were subsequently assessed for social and repetitive behaviors at 20 weeks of age. Daily perinatal exposure to CAPs significantly decreased sociability in male and female mice as measured by the social approach task; however, reductions in reciprocal social interaction and increased grooming behavior were only present in male offspring exposed to CAPs. These findings demonstrate that exposure to particulate air pollutants throughout early neurodevelopment induces long lasting behavioral deficits in a sex-dependent manner and may be an underlying cause of neurodevelopmental disorders such as ASD.

E6020, a synthetic TLR4 agonist, accelerates myelin debris clearance, Schwann cell infiltration, and remyelination in the rat spinal cord

Oligodendrocyte progenitor cells (OPCs) are present throughout the adult brain and spinal cord and can replace oligodendrocytes lost to injury, aging, or disease. Their differentiation, however, is inhibited by myelin debris, making clearance of this debris an important step for cellular repair following demyelination. In models of peripheral nerve injury, TLR4 activation by lipopolysaccharide (LPS) promotes macrophage phagocytosis of debris. Here we tested whether the novel synthetic TLR4 agonist E6020, a Lipid A mimetic, promotes myelin debris clearance and remyelination in spinal cord white matter following lysolecithin-induced demyelination. In vitro, E6020 induced TLR4-dependent cytokine expression (TNFα, IL1β, IL-6) and NF-κB signaling, albeit at ∼10-fold reduced potency compared to LPS. Microinjection of E6020 into the intact rat spinal cord gray/white matter border induced macrophage activation, OPC proliferation, and robust oligodendrogenesis, similar to what we described previously using an intraspinal LPS microinjection model. Finally, a single co-injection of E6020 with lysolecithin into spinal cord white matter increased axon sparing, accelerated myelin debris clearance, enhanced Schwann cell infiltration into demyelinated lesions, and increased the number of remyelinated axons. In vitro assays confirmed that direct stimulation of macrophages by E6020 stimulates myelin phagocytosis. These data implicate TLR4 signaling in promoting repair after CNS demyelination, likely by stimulating phagocytic activity of macrophages, sparing axons, recruiting myelinating cells, and promoting remyelination. This work furthers our understanding of immune-myelin interactions and identifies a novel synthetic TLR4 agonist as a potential therapeutic avenue for white matter demyelinating conditions such as spinal cord injury and multiple sclerosis.

A silver lining of neuroinflammation: Beneficial effects on myelination

Myelin accelerates action potential conduction velocity and provides essential energy support for axons. Unfortunately, myelin and myelinating cells are often vulnerable to injury or disease, resulting in myelin damage, which in turn can lead to axon dysfunction, overt pathology and neurological impairment. Inflammation is a common component of trauma and disease in both the CNS and PNS and therefore an active inflammatory response is often considered deleterious to myelin health. While inflammation can certainly damage myelin, inflammatory processes also can positively affect oligodendrocyte lineage progression, myelin debris clearance, oligodendrocyte metabolism and myelin repair. In the periphery, inflammatory cascades can also augment myelin repair, including processes initiated by infiltrating immune cells as well as by local Schwann cells. In this review, various aspects of inflammation beneficial to myelin repair are discussed and should be considered when designing or implementing anti-inflammatory therapies for CNS and PNS injury involving myelinating cells.

The Use of Sonographically Guided Botulinum Toxin Type A (Dysport) Injections Into the Tensor Fasciae Latae for the Treatment of Lateral Patellofemoral Overload Syndrome

BACKGROUND

Pain in the anterior and lateral parts of the knee during exercise is a common clinical problem for which current management strategies are often unsuccessful.

PURPOSE

To investigate the effect of an ultrasound-guided botulinum toxin (BT) injection into the tensor fasciae latae (TFL), followed by physical therapy, in patients classified with lateral patellofemoral overload syndrome (LPOS) who failed to respond to conventional treatment.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 45 patients (mean ± SD age, 32.4 ± 8.6 years) who met the inclusion criteria of (1) activity-related anterolateral knee symptoms, (2) symptoms lasting longer than 3 months, (3) a pathological abnormality confirmed by magnetic resonance imaging, and (4) previous failed physical therapy received an ultrasound-guided injection of BT into the TFL followed by physical therapy. Patient-reported outcomes were collected at 5 intervals: before the injection; at 1, 4, and 12 weeks after the injection; and at a mean 5 years after the injection. In 42 patients, relative iliotibial band (ITB) length changes were assessed using the modified Ober test at the first 4 time points. A computational model was run to simulate the effect of TFL weakening on gluteus medius (GMed) activity. Statistical analysis was undertaken using 1-way analysis of variance and paired t tests with Bonferroni post hoc correction.

RESULTS

There was a significant improvement in Anterior Knee Pain Scale scores from before the injection (61 ± 15) to 1 (67 ± 15), 4 (70 ± 16), and 12 weeks (76 ± 16) after the injection and in 87% of patients (39/45 patients available for follow-up) at approximately 5 years (from 62.9 ± 15.4 to 87.0 ± 12.5) after the injection (all P < .010). A significant effect on the modified Ober test was identified as a result of the intervention, with an increase in leg drop found at 1 (3° ± 5°), 4 (4° ± 5°), and 12 (7° ± 6°) weeks after the injection compared with before the injection (all P < .010). Simulating a progressive reduction in TFL strength resulted in corresponding increases in GMed activity during gait.

CONCLUSION

An injection of BT into the TFL, combined with physical therapy, resulted in a significant improvement of symptoms in patients with LPOS, which was maintained at 5-year follow-up. This may result from reduced lateral TFL/ITB tension or to an increase in GMed activity in response to inhibition of the TFL.

Non-inferiority of nitric oxide releasing intranasal spray compared to sub-therapeutic antibiotics to reduce incidence of undifferentiated fever and bovine respiratory disease complex in low to moderate risk beef cattle arriving at a commercial feedlot

Undifferentiated fever, or bovine respiratory disease complex (BRDc), is a challenging multi-factorial health issue caused by viral/bacterial pathogens and stressors linked to the transport and mixing of cattle, negatively impacting the cattle feedlot industry. Common practice during processing at feedlots is administration of antibiotic metaphylaxis to reduce the incidence of BRDc. Nitric oxide (NO) is a naturally occurring nano-molecule with a wide range of physiological attributes. This study evaluated the metaphylactic use of intranasal NO releasing spray (NORS) to control BRDc incidence in calves at low-moderate risk of developing BRDc, arriving at a commercial feedlot as compared to conventional antibiotic metaphylaxis. One thousand and eighty crossbred, multiple-sourced, commingled, commercial, weaned beef calves were screened, enrolled, randomized and treated upon arrival. Animals appearing sick were pulled (from their pen) by blinded pen keepers then assessed for BRDc symptoms; blood samples were taken for haptoglobin quantification and the animals were rescued with an antibiotic. After 35 days both groups showed no significant difference in BRDc incidence (5.2% of animals from NORS group and 3.2% from antibiotic group). Average daily weight gain of animals at day 150 for the NORS cohort was 1.17kg compared to 1.18kg for the antibiotic group (p>0.05). There was no significant difference in mortality in the first 35 days (p=0.7552), however, general mortality over 150 days trended higher in the antibiotic cohort. NORS treatment was shown to be safe, causing neither distress nor adverse effects on the animals. This large randomized controlled study in low-moderate BRDc incidence risk calves demonstrates that NORS treatment, as compared to conventional metaphylactic antibiotics, is non-inferior based on BRDc incidence and other metrics like weight and mortality. These data justify further studies in higher BRDc incidence risk populations to evaluate NORS as an alternative strategy to reduce sub-therapeutic metaphylaxis antibiotic use in beef cattle production.

Isolation of α-linolenic acid biohydrogenation products by combined silver ion solid phase extraction and semi-preparative high performance liquid chromatography

Polyunsaturated fatty acids typically found in cattle feed include linoleic (LA) and α-linolenic acid (ALA). In the rumen, microbes metabolize these resulting in the formation of biohydrogenation products (BHP), which can be incorporated into meat and milk. Bioactivities of LA-BHP, including conjugated linoleic acid (cis (c) 9,trans (t) 11-18:2 and t10,c12-18:2) and trans fatty acid isomers (t9-, t10- and t11-18:1) have been investigated, but effects of several BHP unique to ALA have not been extensively studied, and most ALA-BHP are not commercially available. The objective of the present research was to develop methods to purify and collect ALA-BHP using silver ion (Ag(+)) chromatography in sufficient quantities to allow for convenient bioactivity testing in cell culture. Fatty acid methyl esters (FAME) were prepared from perirenal adipose tissue from a cow enriched with ALA-BHP by feeding flaxseed. These were applied to Ag(+)-solid phase extraction, and eluted with hexane with increasing quantities of acetone (1, 2, 10, 20%) or acetonitrile (2%) to pre-fractionate FAME based on degree of unsaturation and double bond configuration. Fractions were collected, concentrated and applied to semi-preparative Ag(+)-high performance liquid chromatography (HPLC) for the isolation and collection of purified isomers, which was accomplished using isocratic elutions with hexane containing differing amounts of acetonitrile (from 0.015 to 0.075%). Purified trans-18:1 isomers collected ranged in purity from 88 to 99%. Purity of the ALA-BHP dienes collected, including c9,t13-18:2, t11,c15-18:2 and t10,c15-18:2, exceeded 90%, while purification of other dienes may require the use of other complementary procedures (e.g. reverse phase HPLC).

Prophylactic nitric oxide treatment reduces incidence of bovine respiratory disease complex in beef cattle arriving at a feedlot

Bovine respiratory disease complex (BRDc), is a challenging multi-factorial health issue caused by viral/bacterial pathogens and stressors linked with the transport and mixing of cattle, negatively impacting the cattle feedlot industry. Nitric oxide (NO) is a naturally occurring molecule with antimicrobial attributes. This study tests whether NO can prevent the symptoms associated with BRDc. Eighty-five, crossbred, multiple-sourced, commingled commercial weaned beef calves were monitored and scored for temperature, white blood count, clinical score, hematology, cortisol levels and neutrophil/lymphocyte ratio. NO treatment or placebo were given once on arrival to the stockyard. After one week 87.5% of sick animals were from the control while 12.5% from treatment groups and after two weeks 72% and 28% respectively. Treatment was shown to be safe, causing neither distress nor adverse effects on the animals. These data show that NO treatment on arrival to the feedlot significantly decreased the incidence of BRDc in this study.

Dexamethasone reduces transport-induced weight losses in beef calves

Dexamethasone was administered intramuscularly at two dose levels (Trial 1 = 0.088 mg kg-1; Trial 2 = 10 mg per calf) to beef calves (Trial 1, n = 60; Trial 2, n = 58) prior to transport by road for 10 and 8 h, to test the effect on transport-induced weight losses. Calves lost significant weight over the transport periods (P < 0.001) but dexamethasone-treated calves lost significantly less weight than control animals (P < 0.004). The relationship between salivary dexamethasone concentrations and weight losses in Trial 1 exhibited a significant trend (r = 0.47, P < 0.06). The correlation of administered dose of dexamethasone (mg kg-1) with weight losses in Trial 2 was significant (r = 0.5, P < 0.006). Dexamethasone administration prior to long-haul transport reduced transport-induced weight losses, and may be an effective method of mitigating transport stress.Key words: Transport, beef calves, dexamethasone, weight losses, salivary cortisol, salivary dexamethasone

Bone mineral density and breaking strength of White Leghorns housed in conventional, modified, and commercially available colony battery cages

Limited opportunity for movement and load-bearing exercise for conventionally caged laying hens leads to bone loss and increased susceptibility to osteoporosis, bone fractures, and cage layer fatigue, all of which compromise hen welfare and have negative consequences for production. The objective of this study was to compare bone mineral density (BMD) and strength measures of White Leghorns housed in conventional battery cages (CONV), cages modified to incorporate a nest box and perch (MOD), and commercially available, furnished colony cages with (CWDB) or without (CWODB) a raised dust bath. Hens reared on floor litter were randomly allocated to 1 of 4 cage systems at 19 wk of age. Hen-day production and egg quality were measured between 20 and 64 wk. At 65 wk, hens were killed, and right femur, tibia, and humerus were excised. Bone mineral density was assessed using quantitative computed tomography, and breaking strength was measured with an Instron Materials Tester. In the femur and tibia, CONV hens exhibited lower total BMD, bone mass, cortical bone area, cortical bone mass, and bone-breaking strength than CWDB, CWODB, and MOD hens. Density and cross-sectional area of bone in the trabecular space was highest in CONV. In the humerus, total and cortical BMD and mass and breaking strength values were higher for colony-housed birds than hens in CONV and MOD. The MOD birds did not exhibit increased humeral BMD or strength measures over CONV hens. These findings provide evidence that hens housed in modified and colony cages, furnished systems that promote load-bearing movement, are better able to preserve cortical structural bone than conventionally caged hens and simultaneously have stronger bones. Furthermore, inclusion of raised amenities that encourage wing loading is necessary to reduce humeral cortical bone loss. The overall absence of correlation between egg production or quality and bone quality measures also suggests that improved bone quality in CWDB, CWODB, and MOD furnished cages is not the result of lowered egg production or quality.

A spectroscopic investigation into the reaction of sodium tetrathionate with cysteine

A spectroscopic investigation into the reaction of sodium tetrathionate with cysteine at pH 5 both at the boil and at room temperature has been carried out. The Raman and infrared spectra of the model compounds cysteine, cysteine-S-sulfonate, cysteine-S-thiosulfonate, sodium thiosulfate and sodium sulfite were also obtained and vibrations involving the sulfur atoms were analyzed in detail. These results were utilized in the interpretation of the spectra obtained from tetrathionate-cysteine reaction mixtures. The reaction supernatants were analyzed by high performance thin layer chromatography while the precipitates were analyzed gravimetrically. It was found that during the reaction, the thiol groups of cysteine are oxidised to give predominantly cysteine-S-sulfonate. Cystine was also detected but was determined gravimetrically to be a minor reaction product. No significant amounts of cysteine-S-thiosulfonate were detected. The reaction is accompanied by the formation of elemental sulfur and a small amount of sulfite. Major reaction pathways are put forth that are consistent with the experimental data.

Embolic phenomena during computer-assisted and conventional total knee replacement

Systemic emboli released during total knee replacement have been implicated as a cause of peri-operative morbidity and neurological dysfunction. We undertook a prospective, double-blind, randomised study to compare the cardiac embolic load sustained during computer-assisted and conventional, intramedullary-aligned, total knee replacement, as measured by transoesophageal echocardiography. There were 26 consecutive procedures performed by a single surgeon at a single hospital. The embolic load was scored using the modified Mayo grading system for echogenic emboli.

Fourteen patients undergoing computer-assisted total knee replacement had a mean embolic score of 4.89 (3 to 7) and 12 undergoing conventional total knee replacement had a mean embolic score of 6.15 (4 to 8) on release of the tourniquet. Comparison of the groups using a two-tailed t-test confirmed a highly significant difference (p = 0.004).

This study demonstrates that computer-assisted knee replacement results in the release of significantly fewer systemic emboli than the conventional procedure using intramedullary alignment.

The use of infrared thermography as an early indicator of bovine respiratory disease complex in calves

Bovine respiratory disease (BRD) complex causes considerable distress to domestic livestock and economic hardship to the beef industry. Furthermore, the resulting extensive use of antimicrobial treatments is a growing concern from the perspective of facilitating antibiotic resistant microbes. The earlier detection of BRD would enable an earlier, more targeted treatment regime and earlier isolation of infected individuals. The objective of the present study was to investigate the use of non-invasive infrared thermography in the early detection of BRD in cattle. Studies were conducted on 133 head of weaned calves. Data demonstrated that infrared thermography was able to identify animals at early stages of illness, often several days to over one week before clinical signs were manifest. Data indicated that 4–6 days prior to the onset of clinical symptoms of BRD, greater positive and negative predictive values and test efficiency for infrared thermography (80%, 65% and 71%, respectively) compared to the industry standard practice of clinical scoring (70%, 45% and 55%, respectively).

The use of digital video recorders (DVRs) for capturing digital video files for use in both The Observer and Ethovision

Before switching a laboratory from analog to digital, for the recording of video files for use in Noldus software such as Ethovision and The Observer, researchers need to proceed with caution. There are obvious advantages in moving to digital recording for behavioral work, including increased storage capacity; no requirement to purchase video tapes; immediate search by date, time, or event; digital images are of higher quality; ability to view study sites remotely by Internet connection; and "smart" features, such as motion detection. But before you throw away your time-lapse video recorders, time code generators, and video multiplexors, there are some important cautions to take account of. Some research groups have bought digital surveillance systems on the assumption that they work with Ethovision and The Observer, only to be disappointed. The vast majority of systems depend on proprietary compression software that must then be converted to work properly in Ethovision or The Observer.

Recurrent synovial chondromatosis of the knee after radical synovectomy and arthrodesis

We describe a case of highly refractory synovial chondromatosis, which recurred despite four arthroscopic synovectomies, a chemical synovectomy, two open synovectomies and an arthrodesis. A review of the literature revealed one similar case. Both presented with marked joint stiffness suggesting a poor prognosis. Although arthrodesis may relieve short-term symptoms it does not prevent further recurrence of disease.

The analysis of Merino wool cuticle and cortical cells by Fourier transform Raman spectroscopy

Wool fibers are comprised of proteins known as alpha-keratins and have a complex morphological structure. The major components of this structure, the cuticle and cortical cells, differ in the conformations of their chains as well as their amino acid compositions. High quality Fourier transform Raman spectra of cortical and cuticle cells isolated from fine Merino wool fibers have been obtained. Raman spectroscopy has been shown to be sensitive to the differences in both secondary structure and amino acid composition. The cortical cells were found to be higher in alpha-helical content as compared to the cuticle cells, which had an increased disordered content. Specific information, consistent with amino acid analysis results, regarding cystine, tyrosine, tryptophan, and phenylalnine residues, were obtained for both the cortical and cuticle cells. In addition, the Raman spectra provided information about free thiol groups, amino acids residues with amide group side chains, and residues with protonated carboxyl group side chains. Middle ir transmission spectra of these isolated cells were also obtained. In comparison to the Raman data, the middle ir spectra were found to be not as rich in information.

Central third bone-patellar tendon-bone anterior cruciate ligament reconstruction: a 5-year follow-up

SUMMARY

Arthroscopically assisted anterior cruciate ligament (ACL) reconstruction using the central third bone-patellar tendon-bone as a free autologous graft is now a widely used procedure. However, little has been published regarding its long-term success. In this retrospective study, we report on the results of 32 patients who were followed-up over 5 years after their reconstruction. Twenty-five patients had improved on their prereconstruction Lysholm and Tegner Activity scores and the same number denied having any symptoms of instability. The mean Lysholm knee score was 88.5. All patients had within 10 degrees of full flexion and 28 had KT-1000 arthrometer readings within 3 mm of their uninjured knee. Only 3 patients had clinical evidence of failure of the graft. We conclude that this technique compares favorably with other alternatives in the long-term treatment of ACL rupture.

Smoking, hypertension, and colonic anastomotic healing; a combined clinical and histopathological study

BACKGROUND

Large bowel anastomotic breakdown occurs as a result of perianastomotic ischaemia. Preservation of the macroscopic arterial supply to the perianastomotic tissues is vital, but little is known about the influence of microvascular disease on anastomotic healing.

AIMS

To study the associations between risk factors for macrovascular disease, the presence of colonic microvascular disease, and the incidence of anastomotic dehiscence.

PATIENTS

147 consecutive colonic surgery patients.

METHODS

The prevalence of smoking, hypertension, diabetes, and ischaemic heart disease were established retrospectively from patient notes. These risk factors were correlated with histopathological assessment of resection margin vasculature and clinical follow up.

RESULTS

Smoking and hypertension were significantly associated with an increased incidence of anastomotic dehiscence and microvascular disease. Microvascular disease was positively correlated with an increased incidence of anastomotic dehiscence.

CONCLUSIONS

Microvascular disease predisposes to anastomotic breakdown. This effect may in part be due to vasospasm in the diseased vessels, which are hypersensitive to serotonin, a vasoactive amine known to be present in increased quantities in the serum of smokers, hypertensives, and after surgery. Treatment with serotonin antagonists in the perioperative period may be beneficial to anastomotic healing, helping to maintain microvascular flow.

Warthin's tumor. A high incidence and no sex predominance in central Pennsylvania

Papillary cystadenolymphoma, or Warthin's tumor, is a monomorphic adenoma found in salivary glands. It nearly always occurs in the parotid gland, and is reported to occur in 5% to 14% of all parotid tumors according to most studies. The tumor has a universally accepted male predominance, with an increasing incidence in females having been reported over the last four decades. A review of all primary parotid gland tumors seen at York (Pa) Hospital for the last 10 years was performed. Warthin's tumor was diagnosed histologically in 42 (30%) of 138 primary parotid gland tumors, with no significant sex predominance identified (22 men, 20 women). A significantly higher percentage of all parotid gland tumors, and especially Warthin's tumor, was associated with smoking in both males and females.

Repair of a traumatic noncircumferential hepatic bile duct defect using a vein patch: case report

Injury to the bile ducts secondary to blunt trauma is a rare but potentially fatal condition that presents a difficult diagnostic and treatment challenge. Various treatment options exist for repair. Vein patch repairs have been criticized because of reports of subsequent fibrosis and stricture formation. This case report describes the successful repair of a traumatic, noncircumferential defect of a hepatic bile duct with a vein patch, and stresses the importance of an adequate duration of stenting.

Variability in preincubation embryo development in domestic fowl. 1. Effects of nest holding time and method of egg storage

Embryos of eggs from Single Comb White Leghorn hens were analyzed to determine whether nest holding time and method of storage had a significant effect on postoviposition embryonic growth prior to incubation. Eggs were collected from 38- to 42-wk-old hens naturally inseminated and housed in floor pens. The experiment had a 2 x 2 factorial arrangement of treatments with two nest holding times and two storage methods. Eggs were collected within 1 h of oviposition, placed on cardboard egg flats, and stored unpacked (Treatment 1), or put on flats, and packed in 30-dozen egg cases (Treatment 2). Eggs in Treatments 3 and 4 were marked within 1 h of oviposition, but remained in the nest for 6 to 7 h. These eggs were separated into unpacked (Treatment 3), and packed (Treatment 4) groups. All eggs were stored at 13.8 C for 4 days. A total of 250 embryos were staged after storage for development using the Eyal-Giladi and Kochav classification. Least square means (LSM) for stage of development were: Treatment 1, 10.76; Treatment 2, 11.52; Treatment 3, 12.41; and Treatment 4, 12.36. For the main effects, nest holding time significantly affected stage of development (P = .0001), but storage method (P = .1140) and nest holding time by storage method interaction (P = .0730) did not. Comparison of LSM of Treatment 1 versus 3 (P = .0001), 2 versus 4 (P = .0152), and 1 versus 2 (P = .0214) were significant, but Treatment 3 versus 4 (P = .8595) was not.(ABSTRACT TRUNCATED AT 250 WORDS)