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Viscerosensory information travels to the brain via vagal afferents, where it is first integrated within the brainstem nucleus tractus solitarii (nTS), a critical contributor to cardiorespiratory function and site of neuroplasticity. We have shown that decreasing input to the nTS via unilateral vagus nerve transection (vagotomy) induces morphological changes in nTS glia and reduces sighs during hypoxia. The mechanisms behind post-vagotomy changes are not well understood. We hypothesized that chronic vagotomy alters cardiorespiratory responses to vagal afferent stimulation via blunted nTS neuronal activity. Male Sprague-Dawley rats (6 weeks old) underwent right cervical vagotomy caudal to the nodose ganglion, or sham surgery. After 1 week, rats were anaesthetized, ventilated and instrumented to measure mean arterial pressure (MAP), heart rate (HR), and splanchnic sympathetic and phrenic nerve activity (SSNA and PhrNA, respectively). Vagal afferent stimulation (2-50 Hz) decreased cardiorespiratory parameters and increased neuronal Ca 2+ measured by in vivo photometry and in vitro slice imaging of nTS GCaMP8m. Vagotomy attenuated both these reflex and neuronal Ca 2+ responses compared to shams. Vagotomy also reduced presynaptic Ca 2+ responses to stimulation (Cal-520 imaging) in the nTS slice. The decrease in HR, SSNA and PhrNA due to nTS nanoinjection of exogenous glutamate also was tempered following vagotomy. This effect was not restored by blocking excitatory amino acid transporters. However, the blunted responses were mimicked by NMDA, not AMPA, nanoinjection and were associated with reduced NR1 subunits in the nTS. Altogether, these results demonstrate that vagotomy induces multiple changes within the nTS tripartite synapse that influence cardiorespiratory reflex responses to afferent stimulation. KEY POINTS: Multiple mechanisms within the nucleus tractus solitarii (nTS) contribute to functional changes following vagal nerve transection. Vagotomy results in reduced cardiorespiratory reflex responses to vagal afferent stimulation and nTS glutamate nanoinjection. Blunted responses occur via reduced presynaptic Ca 2+ activation and attenuated NMDA receptor expression and function, leading to a reduction in nTS neuronal activation. These results provide insight into the control of autonomic and respiratory function, as well as the plasticity that can occur in response to nerve damage and cardiorespiratory disease., (© 2024 The Authors. The Journal of Physiology © 2024 The Physiological Society.)

Obstructive sleep apnea is highly prevalent in Alzheimer's disease (AD). However, brainstem centers controlling respiration have received little attention in AD research, and mechanisms behind respiratory dysfunction in AD are not understood. The nucleus tractus solitarii (nTS) is an important brainstem center for respiratory control and chemoreflex function. Alterations of nTS integrity, like those shown in AD patients, likely affect neuronal processing and adequate control of breathing. We used the streptozotocin-induced rat model of AD (STZ-AD) to analyze cellular changes in the nTS that corroborate previously documented respiratory dysfunction. We used 2 common dosages of STZ (2 and 3 mg/kg STZ) for model induction and evaluated the early impact on cell populations in the nTS. The hippocampus served as control region to identify site-specific effects of STZ. There was significant atrophy in the caudal nTS of the 3 mg/kg STZ-AD group only, an area known to integrate chemoafferent information. Also, the hippocampus had significant atrophy with the highest STZ dosage tested. Both STZ-AD groups showed respiratory dysfunction along with multiple indices for astroglial and microglial activation. These changes were primarily located in the caudal and intermediate nTS. While there was no change of astrocytes in the hippocampus, microglial activation was accompanied by a reduction in synaptic density. Together, our data demonstrate that STZ-AD induces site-specific effects on all major cell types, primarily in the caudal/intermediate nTS. Both STZ dosages used in this study produced a similar outcome and can be used for future studies examining the initial symptoms of STZ-AD., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Exposure to acute intermittent hypoxia (AIH) induces prolonged increases (long term facilitation, LTF) in phrenic and sympathetic nerve activity (PhrNA, SNA) under basal conditions, and enhanced respiratory and sympathetic responses to hypoxia. The mechanisms and neurocircuitry involved are not fully defined. We tested the hypothesis that the nucleus tractus solitarii (nTS) is vital to augmentation of hypoxic responses and the initiation and maintenance of elevated phrenic (p) and splanchnic sympathetic (s) LTF following AIH. nTS neuronal activity was inhibited by nanoinjection of the GABA A receptor agonist muscimol before AIH exposure or after development of AIH-induced LTF. AIH but not sustained hypoxia induced pLTF and sLTF with maintained respiratory modulation of SSNA. nTS muscimol before AIH increased baseline SSNA with minor effects on PhrNA. nTS inhibition also markedly blunted hypoxic PhrNA and SSNA responses, and prevented altered sympathorespiratory coupling during hypoxia. Inhibiting nTS neuronal activity before AIH exposure also prevented the development of pLTF during AIH and the elevated SSNA after muscimol did not increase further during or following AIH exposure. Furthermore, nTS neuronal inhibition after the development of AIH-induced LTF substantially reversed but did not eliminate the facilitation of PhrNA. Together these findings demonstrate that mechanisms within the nTS are critical for initiation of pLTF during AIH. Moreover, ongoing nTS neuronal activity is required for full expression of sustained elevations in PhrNA following exposure to AIH although other regions likely also are important. Together, the data indicate that AIH-induced alterations within the nTS contribute to both the development and maintenance of pLTF., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Ostrowski, Heesch, Kline and Hasser.)

The increasing morbidity and mortality of type 2 diabetic mellitus (T2DM) patients with ischemic heart disease (IHD) highlight an urgent need to identify early biomarkers, which would help to predict individual risk of development of IHD. Here, we postulate that circulating serum-derived micro RNAs (miRNAs) may serve as potential biomarkers for early IHD diagnosis and support the identification of diabetic individuals with a predisposition to undergo IHD. We obtained serum samples from T2DM patients either with IHD or IHD-free and analysed the expression levels of 798 miRNAs using the NanoString nCounter technology platform. The prediction of the putative miRNAs targets was performed using the Ingenuity Pathway Analysis (IPA) software. Gene Ontology (GO) analysis was used to identify the biological function and signalling pathways associated with miRNA target genes. Hub genes of protein-protein interaction (PPI) network were identified by STRING database and Cytotoscape tool. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic value of identified miRNAs. Real-time quantitative polymerase chain reaction (qRT-PCR) was used for nCounter platform data validation. Our data showed that six miRNAs (miR-615-3p, miR-3147, miR-1224-5p, miR-5196-3p, miR-6732-3p, and miR-548b-3p) were significantly upregulated in T2DM IHD patients compared to T2DM patients without IHD. Further analysis indicated that 489 putative target genes mainly affected the endothelin-1 signalling pathway, glucocorticoid biosynthesis, and apelin cardiomyocyte signalling pathway. All tested miRNAs showed high diagnostic value (AUC = 0.779 - 0.877). Taken together, our research suggests that circulating miRNAs might have a crucial role in the development of IHD in diabetic patients and may be used as a potential biomarker for early diagnosis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Bielska, Niemira, Bauer, Sidorkiewicz, Szałkowska, Skwarska, Raczkowska, Ostrowski, Gugała, Dobrzycki and Krętowski.)

Background: Alzheimer's disease (AD) patients frequently present with orthostatic hypotension. This inability to reflexively increase blood pressure on standing is a serious health concern and increases the risk of stroke and cardiovascular diseases., Objective: Since there are no clear mechanisms for orthostatic hypotension in human AD, the present study assessed the autonomic changes that could explain this comorbidity in an AD animal model., Methods: We used the established streptozotocin-induced rat model of AD (STZ-AD), which mimics many hallmark symptoms of sporadic AD in humans. Baroreflex responses were analyzed in anesthetized STZ-AD rats using femoral catheterization for blood pressure and heart rate, and autonomic activity was assessed using specific blockers and splanchnic sympathetic nerve recordings. Expression levels of autonomic receptors at the heart were examined using the western blot technique., Results: Baroreflex function in STZ-AD showed a blunted heart rate (HR) response to low blood pressure challenges, and the maximal sympathetic nerve activity was reduced. Conversely, HR responses to high blood pressure were similar to control, indicating no change in parasympathetic nerve activity. Under resting conditions, autonomic blockade demonstrated a baseline shift to increased sympathetic tone in STZ-AD. Protein expression levels of beta-1 adrenergic receptor and muscarinic acetylcholine receptor M2 in the heart were unchanged., Conclusion: Our study provides the first data on the pathological influence of AD on baroreflex function, which primarily affected the sympathetic nervous system in STZ-AD. These results represent the first mechanisms that may correlate with the orthostatic hypotension in human AD.

In the era of precision medicine, biopsies are playing an increasingly central role in cancer research and treatment paradigms; however, patient outcomes and analyses of biopsy quality, as well as impact on downstream clinical and research applications, remain underreported. Herein, we report biopsy safety and quality outcomes for percutaneous core biopsies of hepatocellular carcinoma (HCC) performed as part of a prospective clinical trial. Patients with a clinical diagnosis of HCC were enrolled in a prospective cohort study for the genetic, proteomic, and metabolomic profiling of HCC at two academic medical centers from April 2016 to July 2020. Under image guidance, 18G core biopsies were obtained using coaxial technique at the time of locoregional therapy. The primary outcome was biopsy quality, defined as tumor fraction in the core biopsy. 56 HCC lesions from 50 patients underwent 60 biopsy events with a median of 8 core biopsies per procedure (interquartile range, IQR, 7-10). Malignancy was identified in 45/56 (80.4%, 4 without pathology) biopsy events, including HCC (40/56, 71.4%) and cholangiocarcinoma (CCA) or combined HCC-CCA (5/56, 8.9%). Biopsy quality was highly variable with a median of 40% tumor in each biopsy core (IQR 10-75). Only 43/56 (76.8%) and 23/56 (41.1%) samples met quality thresholds for genomic or metabolomic/proteomic profiling, respectively, requiring expansion of the clinical trial. Overall and major complication rates were 5/60 (8.3%) and 3/60 (5.0%), respectively. Despite uniform biopsy protocol, biopsy quality varied widely with up to 59% of samples to be inadequate for intended purpose. This finding has important consequences for clinical trial design and highlights the need for quality control prior to applications in which the presence of benign cell types may substantially alter findings., (© 2021. The Author(s).)

The pathology of sickle cell disease is caused by polymerization of the abnormal hemoglobin S upon deoxygenation in the tissues to form fibers in red cells, causing them to deform and occlude the circulation. Drugs that allosterically shift the quaternary equilibrium from the polymerizing T quaternary structure to the nonpolymerizing R quaternary structure are now being developed. Here we update our understanding on the allosteric control of fiber formation at equilibrium by showing how the simplest extension of the classic quaternary two-state allosteric model of Monod, Wyman, and Changeux to include tertiary conformational changes provides a better quantitative description. We also show that if fiber formation is at equilibrium in vivo, the vast majority of cells in most tissues would contain fibers, indicating that it is unlikely that the disease would be survivable once the nonpolymerizing fetal hemoglobin has been replaced by adult hemoglobin S at about 1 y after birth. Calculations of sickling times, based on a recently discovered universal relation between the delay time prior to fiber formation and supersaturation, show that in vivo fiber formation is very far from equilibrium. Our analysis indicates that patients survive because the delay period allows the majority of cells to escape the small vessels of the tissues before fibers form. The enormous sensitivity of the duration of the delay period to intracellular hemoglobin composition also explains why sickle trait, the heterozygous condition, and the compound heterozygous condition of hemoglobin S with pancellular hereditary persistence of fetal hemoglobin are both relatively benign conditions., Competing Interests: The authors declare no competing interest., (Copyright © 2020 the Author(s). Published by PNAS.)

Indolent non-Hodgkin's lymphomas (iNHLs) are incurable with standard therapy and are poorly responsive to checkpoint blockade. Although lymphoma cells are efficiently killed by primed T cells, in vivo priming of anti-lymphoma T cells has been elusive. Here, we demonstrate that lymphoma cells can directly prime T cells, but in vivo immunity still requires cross-presentation. To address this, we developed an in situ vaccine (ISV), combining Flt3L, radiotherapy, and a TLR3 agonist, which recruited, antigen-loaded and activated intratumoral, cross-presenting dendritic cells (DCs). ISV induced anti-tumor CD8 + T cell responses and systemic (abscopal) cancer remission in patients with advanced stage iNHL in an ongoing trial ( NCT01976585 ). Non-responding patients developed a population of PD1 + CD8 + T cells after ISV, and murine tumors became newly responsive to PD1 blockade, prompting a follow-up trial of the combined therapy. Our data substantiate that recruiting and activating intratumoral, cross-priming DCs is achievable and critical to anti-tumor T cell responses and PD1-blockade efficacy.

Unsignaled stress can have profound effects on animal behavior. While most investigation of stress-effects on behavior follows chronic exposures, less is understood about acute exposures and potential after-effects. We examined walking activity in Drosophila following acute exposure to high temperature or electric shock. Compared to initial walking activity, flies first increase walking with exposure to high temperatures then have a strong reduction in activity. These effects are related to the intensity of the high temperature and number of exposures. The reduction in walking activity following high temperature and electric shock exposures survives context changes and lasts at least five hours. Reduction in the function of the biogenic amines octopamine / tyramine and serotonin both strongly blunt the increase in locomotor activity with high temperature exposure. However, neither set of biogenic amines alter the long lasting depression in walking activity after exposure., Competing Interests: The authors have declared that no competing interests exist.

In addition to its regulatory function in the formation of red blood cells (erythropoiesis) in vertebrates, Erythropoietin (Epo) contributes to beneficial functions in a variety of non-hematopoietic tissues including the nervous system. Epo protects cells from apoptosis, reduces inflammatory responses and supports re-establishment of compromised functions by stimulating proliferation, migration and differentiation to compensate for lost or injured cells. Similar neuroprotective and regenerative functions of Epo have been described in the nervous systems of both vertebrates and invertebrates, indicating that tissue-protective Epo-like signaling has evolved prior to its erythropoietic function in the vertebrate lineage. Epo mediates its erythropoietic function through a homodimeric Epo receptor (EpoR) that is also widely expressed in the nervous system. However, identification of neuroprotective but non-erythropoietic Epo splice variants and Epo derivatives indicated the existence of other types of Epo receptors. In this review, we summarize evidence for potential Epo receptors that might mediate Epo's tissue-protective function in non-hematopoietic tissue, with focus on the nervous system. In particular, besides EpoR, we discuss three other potential neuroprotective Epo receptors: (1) a heteroreceptor consisting of EpoR and common beta receptor (βcR), (2) the Ephrin (Eph) B4 receptor and (3) the human orphan cytokine receptor-like factor 3 (CRLF3)., Competing Interests: The authors declare no conflict of interest.

Feedback mechanisms in operant learning are critical for animals to increase reward or reduce punishment. However, not all conditions have a behavior that can readily resolve an event. Animals must then try out different behaviors to better their situation through outcome learning. This form of learning allows for novel solutions and with positive experience can lead to unexpected behavioral routines. Learned helplessness, as a type of outcome learning, manifests in part as increases in escape latency in the face of repeated unpredicted shocks. Little is known about the mechanisms of outcome learning. When fruit fly Drosophila melanogaster are exposed to unpredicted high temperatures in a place learning paradigm, flies both increase escape latencies and have a higher memory when given control of a place/temperature contingency. Here we describe discrete serotonin neuronal circuits that mediate aversive reinforcement, escape latencies, and memory levels after place learning in the presence and absence of unexpected aversive events. The results show that two features of learned helplessness depend on the same modulatory system as aversive reinforcement. Moreover, changes in aversive reinforcement and escape latency depend on local neural circuit modulation, while memory enhancement requires larger modulation of multiple behavioral control circuits.

Sickle cell disease is caused by a mutant form of hemoglobin that polymerizes under hypoxic conditions, increasing rigidity, fragility, calcium influx-mediated dehydration, and adhesivity of red blood cells. Increased red cell fragility results in hemolysis, which reduces nitric oxide (NO) bioavailability, and induces platelet activation and inflammation leading to adhesion of circulating blood cells. Nitric Oxide inhibits adhesion and platelet activation. Nitrite has emerged as an attractive therapeutic agent that targets delivery of NO activity to areas of hypoxia through bioactivation by deoxygenated red blood cell hemoglobin. In this study, we demonstrate anti-platelet activity of nitrite at doses achievable through dietary interventions with comparison to similar doses with other NO donating agents. Unlike other NO donating agents, nitrite activity is shown to be potentiated in the presence of red blood cells in hypoxic conditions. We also show that nitrite reduces calcium associated loss of phospholipid asymmetry that is associated with increased red cell adhesion, and that red cell deformability is also improved. We show that nitrite inhibits red cell adhesion in a microfluidic flow-channel assay after endothelial cell activation. In further investigations, we show that leukocyte and platelet adhesion is blunted in nitrite-fed wild type mice compared to control after either lipopolysaccharide- or hemolysis-induced inflammation. Moreover, we demonstrate that nitrite treatment results in a reduction in adhesion of circulating blood cells and reduced red blood cell hemolysis in humanized transgenic sickle cell mice subjected to local hypoxia. These data suggest that nitrite is an effective anti-platelet and anti-adhesion agent that is activated by red blood cells, with enhanced potency under physiological hypoxia and in venous blood that may be useful therapeutically., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Some memories last longer than others, with some lasting a lifetime. Using several approaches memory phases have been identified. How are these different phases encoded, and do these different phases have similar temporal properties across learning situations? Place memory in Drosophila using the heat-box provides an excellent opportunity to examine the commonalities of genetically-defined memory phases across learning contexts. Here we determine optimal conditions to test place memories that last up to three hours. An aversive temperature of 41°C was identified as critical for establishing a long-lasting place memory. Interestingly, adding an intermittent-training protocol only slightly increased place memory when intermediate aversive temperatures were used, and slightly extended the stability of a memory. Genetic analysis of this memory identified four genes as critical for place memory within minutes of training. The role of the rutabaga type I adenylyl cyclase was confirmed, and the latheo Orc3 origin of recognition complex component, the novel gene encoded by pastrel, and the small GTPase rac were all identified as essential for normal place memory. Examination of the dopamine and ecdysone receptor (DopEcR) did not reveal a function for this gene in place memory. When compared to the role of these genes in other memory types, these results suggest that there are genes that have both common and specific roles in memory formation across learning contexts. Importantly, contrasting the timing for the function of these four genes, plus a previously described role of the radish gene, in place memory with the temporal requirement of these genes in classical olfactory conditioning reveals variability in the timing of genetically-defined memory phases depending on the type of learning., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Serotonin (5-HT), and its 5-HT1A receptor (5-HT1AR) subtype, is a powerful modulator of the cardiorespiratory system and its sensory reflexes. The nucleus tractus solitarii (nTS) serves as the first central station for visceral afferent integration and is critical for cardiorespiratory reflex responses. However, the physiological and synaptic role of 5-HT1ARs in the nTS is relatively unknown. In the present study, we examined the distribution and modulation of 5-HT1ARs on cardiorespiratory and synaptic parameters in the nTS. 5-HT1ARs were widely distributed to cell bodies within the nTS but not synaptic terminals. In anesthetized rats, activation of 5-HT1ARs by microinjection of the 5-HT1AR agonist 8-OH-DPAT into the caudal nTS decreased minute phrenic neural activity via a reduction in phrenic amplitude. In brain stem slices, 8-OH-DPAT decreased the amplitude of glutamatergic tractus solitarii-evoked excitatory postsynaptic currents, and reduced overall spontaneous excitatory nTS network activity. These effects persisted in the presence of GABAA receptor blockade and were antagonized by coapplication of 5-HT1AR blocker WAY-100135. 5-HT1AR blockade alone had no effect on tractus solitarii-evoked excitatory postsynaptic currents, but increased excitatory network activity. On the other hand, GABAergic nTS-evoked inhibitory postsynaptic currents did not change by activation of the 5-HT1ARs, but spontaneous inhibitory nTS network activity decreased. Blocking 5-HT1ARs tended to increase nTS-evoked inhibitory postsynaptic currents and inhibitory network activity. Taken together, 5-HT1ARs in the caudal nTS decrease breathing, likely via attenuation of afferent transmission, as well as overall nTS network activity., (Copyright © 2014 the American Physiological Society.)

The cytokine erythropoietin (Epo) initiates adaptive cellular responses to both moderate environmental challenges and tissue damaging insults in various non-hematopoietic mammalian tissues including the nervous system. Neuroprotective and neuroregenerative functions of Epo in mammals are mediated through receptor-associated Janus kinase 2 and intracellular signaling cascades that modify the transcription of Epo-regulated genes. Signal transducers and activators of transcription (STAT) and phosphoinositol-3-kinase (PI3K) represent key components of two important Epo-induced transduction pathways. Our previous study on insects revealed neuroprotective and regenerative functions of recombinant human Epo (rhEpo) similar to those in mammalian nervous tissues. Here we demonstrate that rhEpo effectively rescues primary cultured locust brain neurons from apoptotic cell death induced by hypoxia or the chemical compound H-7. The Janus kinase inhibitor AG-490 and the STAT inhibitor sc-355797 abolished protective effects of rhEpo on locust brain neurons. In contrast, inhibition of PI3K with LY294002 had no effect on rhEpo-mediated neuroprotection. The results indicate that rhEpo mediates the protection of locust brain neurons through interference with apoptotic pathways by the activation of a Janus kinase-associated receptor and STAT transcription factor(s). The involvement of similar transduction pathways in mammals and insects for the mediation of neuroprotection and support of neural regeneration by Epo indicates that an Epo/Epo receptor-like signaling system with high structural and functional similarity exists in both groups of animals. Epo-like signaling involved in tissue protection appears to be an ancient beneficial function shared by vertebrates and invertebrates., (Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.)

In addition to its function as a regulator of hematopoiesis, the cytokine erythropoietin (Epo) initiates adaptive cellular responses to both moderate environmental challenges and tissue damaging insults in various non-hematopoietic mammalian tissues. Epo's neuroprotective and neuroregenerative functions mediated through janus kinases (JAK)/signal transducers and activators of transcription (STAT) transduction pathways and regulation of Epo and Epo receptor expression in the nervous system by hypoxia inducible factor (HIF) have been documented in a variety of in vitro and in vivo studies and homologs of the human Epo gene are present in fish, amphibians and mammals. The present study reproduces the hallmarks of Epo-mediated mammalian neuroprotection in the grasshopper nervous system. Recombinant human Epo (rhEpo) increases the survival of dissociated grasshopper brain neurons under normoxic and hypoxic conditions and promotes the regeneration of neurites in vitro. In addition, reestablishment of sound source localization after unilateral tympanic nerve crush injury was accelerated and more complete after application of rhEpo, demonstrating in vivo support of auditory receptor cell axon regeneration. Immunoblots of central nervous tissue extracts from mouse, grasshopper, crayfish and leech labeled protein bands of ∼38 kDa, fitting to the molecular weight of Epo reported in earlier studies. These results indicate that a ligand/receptor system that shares structural and functional similarities with mammalian Epo and Epo receptor exerts neuroprotective and neuroregenerative effects in insects. With both upstream (HIF system) and downstream (JAK/STAT pathway) elements of the mammalian Epo system being present in insects and other invertebrates, Epo-like signaling involved in tissue protection appears to be an ancient beneficial function shared by vertebrates and invertebrates., (Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.)

The genetic mechanisms that influence memory formation and sensitivity to the effects of ethanol on behavior in Drosophila have some common elements. So far, these have centered on the cAMP/PKA signaling pathway, synapsin and fas2-dependent processes, pumilio-dependent regulators of translation, and a few other genes. However, there are several genes that are important for one or the other behaviors, suggesting that there is an incomplete overlap in the mechanisms that support memory and ethanol sensitive behaviors. The basis for this overlap is far from understood. We therefore examined memory in arouser (aru) mutant flies, which have recently been identified as having ethanol sensitivity deficits. The aru mutant flies showed memory deficits in both short-term place memory and olfactory memory tests. Flies with a revertant aru allele had wild-type levels of memory performance, arguing that the aru gene, encoding an EPS8L3 product, has a role in Drosophila memory formation. Furthermore, and interestingly, flies with the aru(8-128) insertion allele had deficits in only one of two genetic backgrounds in place and olfactory memory tests. Flies with an aru imprecise excision allele had deficits in tests of olfactory memory. Quantitative measurements of aru EPS8L3 mRNA expression levels correlate decreased expression with deficits in olfactory memory while over expression is correlated with place memory deficits. Thus, mutations of the aru EPS8L3 gene interact with the alleles of a particular genetic background to regulate arouser expression and reveals a role of this gene in memory.

Objectives: Deep vein thrombosis (DVT) is a major source of postoperative morbidity and mortality and is currently a major quality improvement initiative. Mechanical and pharmacological prophylaxis is effective in preventing postoperative thromboembolic events, yet it remains underutilized in the clinical setting. Thus, the objective of this study was to develop and implement a computerized DVT risk assessment program in the electronic medical record and determine its effect on compliance with DVT prophylaxis guidelines., Methods: A standardized DVT risk assessment program was developed and incorporated into the Computerized Patient Record System for all surgical patients at the Jesse Brown Veterans Affairs Medical Center. Four hundred consecutive surgical patients before and after implementation were evaluated for DVT risk, the prescription of pharmacological and mechanical DVT prophylaxis, and the development of thromboembolic events., Results: With implementation of the DVT risk assessment program, the number of patients receiving the recommended pharmacological prophylaxis preoperatively more than doubled (14% to 36%) (P < .001), and use of sequential compression devices (SCD) increased 40% (P < .001). Overall, the percentage of at-risk patients receiving the recommended combined DVT prophylaxis of SCD and pharmacological prophylaxis increased nearly seven-fold (5% to 32%) (P < .001). The assessment also improved use of prophylaxis postoperatively, increasing SCD use by 27% (P < .001). With respect to DVT occurrence, there was an 80% decrease in the incidence of postoperative DVT at 30 days and a 36% decrease at 90 days; however, this did not reach statistical significance due to the low event rate., Conclusions: The creation and implementation of a standardized DVT risk assessment program in the electronic medical record significantly increased use of pharmacological and mechanical DVT prophylaxis before surgery in a Veterans Affairs Medical Center setting.

Aim: D-Tagatose (D-tag), a hexose bulk sweetener, does not affect plasma glucose levels when orally administered to rodents. Additionally, D-tag attenuates the rise in plasma glucose after mice are administered oral sucrose. The current study was undertaken to investigate the acute glycaemic effects of oral D-tag alone or in combination with oral glucose in human subjects with and without type 2 diabetes mellitus. Glycaemic responses to D-tag also were investigated in subjects after oral sucrose to examine whether the glucose-lowering effects of D-tag in rodents may result from a direct inhibition of intestinal disaccharidases., Methods: Eight normal and eight subjects with diabetes mellitus were administered 75 g of glucose, 75 g of D-tag, or 75 g of D-tag 30 min prior to a 75 g oral glucose tolerance test (OGTT). Five patients with diabetes mellitus were challenged with a 75 g oral sucrose tolerance test (OSTT) with and without oral pre-treatment with 75 g of D-tag. Patients with diabetes mellitus also received separate 0, 10, 15, 20 and 30 g of D-tag 30 min prior to a 75 g OGTT., Results: Oral loading with D-tag alone led to no changes in glucose or insulin levels in either normal patients or those with diabetes mellitus. Pre-OGTT treatment with 75 g D-tag, however, attenuated the rise in glucose levels in patients with diabetes mellitus (p < 0.02 at 60 and 180 min, and p < 0.01 at 120 min). The glucose area under the curve (AUC) was reduced significantly also by pre-treatment with D-tag in a dose-dependent manner in patients with diabetes mellitus (p < 0.05 for 10 g D-tag, p < 0.001 for 20 g D-tag, and p = 0.0001 for 30 g D-tag). In patients with diabetes mellitus 75 g D-tag similarly attenuated the rise in glucose following an OSTT (p < 0.01 at 30 min, and p < 0.02 at 60 min). Pre-treatment with 75 g D-tag also tended to blunt the rise in insulin following an OGTT in normal patients (p = 0.07 for insulin AUC) but not patients with diabetes mellitus (p = 0.66). Following 75 g of oral D-tag in four normal patients, plasma D-tag levels rose to a mean peak level of 3.6 mg/dl at 90 min. The administration of 75 g D-tag led to diarrhoea, nausea and/or flatulence in 100% of subjects. When D-tag was administered at lower doses ranging from 10 g to 30 g, only three of 10 patients with diabetes mellitus had gastrointestinal symptoms which were much more mild than those evoked by 75 g D-tag., Conclusions: These results show that oral D-tag significantly blunts the rise in plasma glucose seen after oral glucose in patients with diabetes mellitus in a dose-dependent manner without significantly affecting insulin levels. The minimal elevation of plasma D-tag levels in normal patients and the adverse gastrointestinal effects seen following larger doses of D-tag support poor absorption of this hexose and suggest that D-tag may act by attenuating glucose absorption in the intestine. D-tag may be a useful therapeutic adjunct in the management of type 2 diabetes mellitus.

There is currently no "magic bullet" available for individuals interested in smoking cessation. There are, however, many techniques that may help these individuals, some involving drug therapy. Research has shown that the habitual use of cigarettes and other tobacco products poses a serious health threat to millions of Americans. Because smoked and smokeless tobacco use produces many changes to the oral cavity and nasopharynx, dentists are in a unique position to observe changes and point out these changes to their patients. Patients who smoke should be given information about malignant, precancerous, and nonmalignant changes in the oral and perioral areas. This proactive activity can be helpful to encourage patients to terminate their smoking addiction.

We present a detailed study of a 59-year-old white woman with mixed sclerosing bone dystrophy: the rare occurrence of two or more sclerosing bone dysplasias in a single subject. She exhibited features of osteopoikilosis, osteopathia striata and melorheostosis. The symptoms were primarily the result of the melorheostosis lesions which were distributed within the C6 sclerotome. This is an unusual case of mixed sclerosing bone dystrophy in that the upper extremity was the main site of involvement, instead of the usual symmetrical involvement of all limbs. The patient developed a recalcitrant lateral epicondylitis in the un-involved contralateral elbow that required surgical treatment.

This article describes a technique for interdigital web space deepening, which is applicable to incomplete syndactyly proximal to the proximal interphalangeal joint and to dorsal web space adduction contracture resulting from thermal injury. It consists of a dorsal rectangular flap and two palmar triangular flaps. The flaps are reversed to release dorsal adduction contracture. This procedure provides a broad commissure with a natural slope. A skin graft is avoided. A mathematical model shows that when the length-width ratio of the flaps is 1:1, the surface area of each flap is greater than or equal to the surface area of the defect it covers and the length of every flap edge is equal to or greater than its corresponding defect edge. If a web has a low apex angle and the skin is elastic, the length-width ratio may be as great as 1.5:1. The flaps will still cover the defects and small inequalities between certain flap and defect edges will be accommodated.

A case of irreducible complete dorsoulnar dislocation of the proximal phalanx of the thumb is presented. The pathologic anatomy included intersubstance tears of the ulnar collateral ligament and dorsal capsule and avulsions of the palmar plate and radial collateral ligament from their metacarpal attachments. The palmar plate blocked reduction, as did the radial collateral ligament that was caught on the margin of a tear in the adductor aponeurosis and on the tendon of the extensor pollicis longus. A review of the English-language literature indicates that this pathologic anatomy has not been described.

A case of dorsal dislocation of the trapezoid associated with dorsal subluxation of the carpometacarpal joints of the index and long fingers is described. The initial trapezoid subluxation was overlooked and it progressed quickly to a complete dislocation. Open reduction and capsular repair without internal fixation was followed by early recurrent trapezoid subluxation. Repeat open reduction combined with a limited intercarpal arthrodesis was used as a salvage procedure and produced a good result.

Irreducible palmar dislocation of the proximal interphalangeal joint in which the central slip remains intact is a rare injury. A noose formed by the extensor mechanism traps the condyle of the proximal phalanx. The collateral ligament is avulsed and the volar plate is disrupted. Closed reduction was unsuccessful in this case. Open reduction achieved a good result.

Two cases of congenital pseudarthrosis of the ulna in patients with neurofibromatosis were followed up for 15 and 8 years, respectively. In both cases conventional bone grafting failed. The solution in one case was production of a one-bone forearm. In the other, osteotomy of the radius, resection of the ulnar pseudarthrosis, and stabilization of the distal radioulnar joint achieved a good result. The literature suggests that free vascularized bone grafting, electrical stimulation, formation of a one-bone forearm, or osteotomy of the uninvolved bone with or without resection of the pseudarthrosis should be considered as treatment alternatives.

An improved fibreoptic in vivo haemoreflection system has been used in over 200 patients. Continuous recording of oxygen saturation while moving the catheter permits measurement of simultaneous pressure and oxygen saturation at almost an unlimited number of sites through the right heart. The oxygen saturation can be continuously monitored and the response is sufficiently fast to permit investigation of changes in oxygen saturation during portions of the cardiac cycle. Dye dilution curves have been recorded from over 200 patients. The only blood withdrawn for the dye dilution curve was the 3 ml needed for checking the calibration of the instrument. We have found that the calibration is extremely stable. In some instances where it has been deemed impractical to obtain blood for calibration, the calibration factor for each catheter may be used. In any case, the calibration check is performed at the end of the study and does not present problems of sterility. The calibration factor may yield a correction factor which then applies uniformly to all the cardiac output values obtained during the study.