Human-relevant near-organ neuromodulation of the immune system via the splenic nerve

Neuromodulation of immune function by stimulating the autonomic connections to the spleen has been demonstrated in rodent models. Consequently, neuroimmune modulation has been proposed as a new therapeutic strategy for the treatment of inflammatory conditions. However, demonstration of the translation of these immunomodulatory mechanisms in anatomically and physiologically relevant models is still lacking. Additionally, translational models are required to identify stimulation parameters that can be transferred to clinical applications of bioelectronic medicines. Here, we performed neuroanatomical and functional comparison of the mouse, rat, pig, and human splenic nerve using in vivo and ex vivo preparations. The pig was identified as a more suitable model of the human splenic innervation. Using functional electrophysiology, we developed a clinically relevant marker of splenic nerve engagement through stimulation-dependent reversible reduction in local blood flow. Translation of immunomodulatory mechanisms were then assessed using pig splenocytes and two models of acute inflammation in anesthetized pigs. The pig splenic nerve was shown to locally release noradrenaline upon stimulation, which was able to modulate cytokine production by pig splenocytes. Splenic nerve stimulation was found to promote cardiovascular protection as well as cytokine modulation in a high- and a low-dose lipopolysaccharide model, respectively. Importantly, splenic nerve–induced cytokine modulation was reproduced by stimulating the efferent trunk of the cervical vagus nerve. This work demonstrates that immune responses can be modulated by stimulation of spleen-targeted autonomic nerves in translational species and identifies splenic nerve stimulation parameters and biomarkers that are directly applicable to humans due to anatomical and electrophysiological similarities.

The inflammatory status of the body is monitored and regulated through the neuroimmune axis, connecting the brain to the immune system via both humoral and neural pathways (1–3). In particular, the inflammatory reflex (3) controls systemic immune responses; detection of inflammatory stimuli in the periphery is communicated to the brain that activates outflow of neural signals to promote peripheral immune responses proportional to the threat. Studies in rodent models have identified the cholinergic anti-inflammatory pathway (CAIP) as the brain’s efferent response to infection and inflammation through peripheral neurotransmitters released in lymphoid organs, mainly the spleen (4, 5). Within this pathway, the peripheral connection between the vagus nerve (VN), the splenic nerve (SpN), and its terminal release of noradrenaline (NA) into the spleen have been identified as crucial components of this neural circuit (6–8) (SI Appendix, Fig. S1A).Importantly, the CAIP can be harnessed to promote immune control. Activation of the cervical VN by electrical stimulation (vagus nerve stimulation—VNS; SI Appendix, Fig. S1A) has been shown to be effective in reducing lipopolysaccharide (LPS)-induced levels of tumor necrosis factor alpha (TNF-α) (4, 6, 7) and in preclinical rodent models of chronic inflammatory diseases (9, 10). Murine models have generally been used to demonstrate biological proof of concepts of novel neuromodulation therapies in this and other contexts. However, the development of clinical bioelectronic medicines requires the accurate estimation and validation of stimulation parameters in a histologically, surgically, and anatomically relevant model to define device and therapy requirements. The translation of stimulation parameters from rodent to human is hampered by anatomical (e.g., size of nerves), histological (e.g., number of axons, connective tissue thickness, proportion of adipose tissue), and physiological (e.g., immunological) differences. Therefore, it is suggested that the use of large animal models, human tissues, and in silico modeling are more appropriate for the optimization and scaling of human-relevant parameters (11, 12).Although early clinical feasibility studies have provided preliminary evidence of immunomodulatory effects of VNS in patients (13, 14), clear demonstration of the translation of the splenic anti-inflammatory pathway in clinically relevant species is currently lacking in the literature. The VN has a functionally and anatomically complex composition. In animals and humans, the VN contains both afferent and efferent axons of varying size (large, medium, and small) and degree of myelination (heavily myelinated, lightly myelinated, and unmyelinated axons) innervating multiple organs and muscles (15). As a consequence, currently used VNS results in activation of off-target circuits (SI Appendix, Fig. S1A) that can cause dysphonia, coughing, hoarseness, pain, and dyspnea (16–18); in some patients, these can be managed and can also improve over time (18). Further, it remains unclear which axons (efferent versus afferent, myelinated versus unmyelinated) within the VN relay immunomodulatory signals to peripheral organs (19, 20). As a result, it is difficult to optimize the stimulation parameters necessary to activate axons within the VN which carry signals to the spleen. Typically, clinical parameters are selected based on the individual patient’s tolerance of off-target effects (13, 21) without direct evidence of activation of the anti-inflammatory pathway because of a lack of an organ-specific biomarker. Since the SpN directly transmits neural signals to the spleen and is the fundamental nodal circuit in mediating the anti-inflammatory response (22), SpN stimulation (SpNS) may represent an alternative modality providing the opportunity for near-organ modulation of the immune system (SI Appendix, Fig. S1 B and C). Proof of concept experiments in rodents have shown that immune responses can indeed be modulated by stimulation of the SpN with comparable cytokine suppressive effects to VNS (7, 8, 23).Here, we anatomically, histologically, and functionally compared the mouse, rat, pig, and human SpN, demonstrating the superiority of the pig as a translational model of the human SpN. We then performed functional in vivo pig electrophysiological studies to identify organ-specific physiological biomarkers that can be used to assess nerve engagement and to refine stimulation parameters. Finally, we assessed the large animal translation of the spleen-dependent anti-inflammatory pathway in the pig using in vitro splenocyte preparations together with two in vivo models of acute inflammation.     

Clinical profile, diagnosis and management of patients presenting with symptomatic pulmonary embolism

OBJECTIVE: To study the clinical profile and diagnostic methods in patients with symptomatic pulmonary embolism (PE). METHODS: Prospective assessment of clinical features, radiology and outcome of patients presenting with symptomatic PE over an 18-month period. RESULTS: During study period, 24 patients with a mean age of 39 +/- 12.1 years were diagnosed to have symptomatic pulmonary embolism. Dyspnoea (91.7%) and cough (58.3%) were the predominant complaints. Spiral computed tomographic pulmonary angiography (CTPA) was performed in 21 (87.5%) patients and perfusion scans in 14 (58.4%) patients. Echocardiography performed in all patients revealed evidence of pulmonary artery hypertension and right ventricular dyskinesia in 20 (83.3%) and 15 (62.5%) patients, respectively. Thrombolysis with streptokinase was performed in 14 (58.3%) patients. All patients received low molecular weight heparin followed by warfarin. Of the 24 patients, 20 (83.3%) were discharged and are under regular follow-up; four patients died. CONCLUSIONS: Pulmonary embolism is a common problem and can be easily diagnosed provided it is clinically suspected. Early diagnosis and aggressive management is the key to successful outcome.     

Enhanced factor H binding to sialylated Gonococci is restricted to the sialylated lacto-N-neotetraose lipooligosaccharide species: implications for serum resistance and evidence for a bifunctional lipooligosaccharide sialyltransferase in Gonococci

We isolated serologically identical (by serovar determination and porin variable region [VR] typing) strains of Neisseria gonorrhoeae from an infected male and two of his monogamous female sex partners. One strain (termed 398078) expressed the L1 (Galalpha1 --> 4 [corrected] Galbeta1 --> 4Glcbeta1 --> 4HepI) lipooligosaccharide (LOS) structure exclusively; the other (termed 398079) expressed the lacto-N-neotetraose (LNT; Galbeta1 --> 4GlcNAcbeta1 --> 3Galbeta1 --> 4Glcbeta1 --> 4HepI) LOS structure. The strain from the male index case expressed both glycoforms and exhibited both immunotypes. Nuclear magnetic resonance analysis revealed that sialic acid linked to the terminal Gal of L1 LOS via an alpha2 --> 6 linkage and, as expected, to the terminal Gal of LNT LOS via an alpha2--> 3 linkage. Insertional inactivation of the sialyltransferase gene (known to sialylate LNT LOS) abrogated both L1 LOS sialylation and LNT LOS sialylation, suggesting a bifunctional nature of this enzyme in gonococci. Akin to our previous observations, sialylation of the LNT LOS of strain 398079 enhanced the binding of the complement regulatory molecule, factor H. Rather surprisingly, factor H did not bind to sialylated strain 398078. LOS sialylation conferred the LNT LOS-bearing strain complete (100%) resistance to killing by even 50% nonimmune normal human serum (NHS), whereas sialylation of L1 LOS conferred resistance only to 10% NHS. The ability of gonococcal sialylated LNT to bind factor H confers high-level serum resistance, which is not seen with sialylated L1 LOS. Thus, serum resistance mediated by sialylation of gonococcal L1 and LNT LOS occurs by different mechanisms, and specificity of factor H binding to sialylated gonococci is restricted to the LNT LOS species.     

Complete genome sequence analysis of Japanese encephalitis virus isolated from a horse in India

The complete genome of the Japanese encephalitis virus (JEV) strain JEV/eq/India/H225/2009(H225), isolated from an infected horse in India, was sequenced and compared to previously published JEV genomes. H225 genome was 10,977-nucleotides long, comprising a single ORF of 10,299-nucleotides, a 5′-UTR of 95 nucleotides and a 3′-UTR of 582 nucleotides. The H225 genome showed high levels of sequence identity with 47 fully sequenced JEV genomes, ranging from 99.3 % to 75.5 % for nucleotides and 99.2 % to 91.5 % for amino acid sequences. Phylogenetic analysis of the full-length sequence indicated that the H225 strain belongs to genotype III and is closely related to the Indian JEV strain Vellore P20778. A comparison of amino acids associated with neurovirulence in the E proteins and non-structural proteins of known virulent and attenuated JEV strains suggested H225 to be a highly virulent strain. This is the first report of whole-genome sequencing of a genotype III JEV genome isolated from equines.     

Acne Knowledge of Hispanic Parents of Teenagers with Mild to Moderate Acne

We performed a cross‐sectional study of Hispanic and non‐Hispanic parents of children with acne using a survey designed to determine their level of awareness of acne and its treatment; 82% of Hispanic parents and 40% of non‐Hispanic parents agreed that a health care provider should treat mild acne (p < 0.001). Hispanic parents of adolescents with acne agreed more frequently than non‐Hispanic parents that children with mild and moderate acne should be taken to a health care provider for treatment, but they tended not to visit health care providers. Future studies should aim to determine the reasons for this discrepancy, after which culturally sensitive educational programs can be developed to address this disparity.     

Role of tissue harmonic imaging in focal hepatic lesions: comparison with conventional sonography

Background: The purpose of the present study was to compare iissue harmonic imaging (THI) and conventional sonography in focal hepatic lesions. Methods: Fifty patients with focal hepatic lesions were enrolled for study. Conventional grayscale and THI was performed in all the patients and two sets of images of the lesions were recorded (one each for THI and conventional) and assessed for fluid–solid differentiation, detail and overall image quality. These images were compared with conventional sonographic images and graded better, same or worse as per the case. Lesions were confirmed by fine‐needle aspiration cytology (FNAC)/surgery/other modalities such as computed tomography (CT) or magnetic resonance imaging (MRI). Results: Out of 50 patients with focal hepatic lesions, 21 patients had metastatic lesions (two single; 19 multiple) five patients had hepatocellular carcinoma (HCC), five patients had hydatid cysts, nine had simple hepatic cyst whereas five patients had liver abscess, three had focal fatty infiltration; and lymphoma and hemangioma were seen in one patient each. The first observer ranked THI better than standard sonography in 40 patients (80%) for fluid–solid differentiation, in 38 (76%) for detail and in 39 (78%) for overall image quality. The second observer ranked THI better than standard sonography in 39 patients (78%) for fluid–solid differentiation, in 40 (80%) for detail and in 42 (84%) for overall image quality. Tissue harmonic imaging provided additional information in eight patients (16%) and resulted in treatment alteration in three patients (6%). Conclusion: Tissue harmonic imaging was significantly better than conventional sonography for fluid–solid differentiation, detail and total image quality in focal hepatic lesions, especially in obese patients and patients with poor acoustic window.     

Associations Between Abortion Services and Acceptance of Postabortion Contraception in Six Indian States

Women receiving induced abortions or postabortion care are at high risk of subsequent unintended pregnancy, and intervals of less than six months between abortion and subsequent pregnancy may be associated with adverse outcomes. This study highlights the prevalence and attributes of postabortion contraceptive acceptance from 2,456 health facilities in six major Indian states, among 292,508 women who received abortion care services from July 2011 through June 2014. Eighty‐one percent of the women accepted postabortion contraceptive methods: 53 percent short‐term, 11 percent intrauterine devices, and 16 percent sterilization. Postabortion contraceptive acceptance was highest among women who were aged 25 years and older, received first‐trimester services, received induced abortion, attended primary‐level health facilities, and had medical abortions. Doctors receiving post‐training support were more likely to offer contraceptives, but no association was observed between such support and acceptance of IUDs or sterilization. Comprehensive service‐delivery interventions, including ensuring availability of skilled providers and contraceptive commodities, offering clinical mentoring for providers, identifying and addressing provider bias, and improving provider counseling skills, can increase postabortion contraceptive acceptance and reduce unintended pregnancy.     

Mainstreaming of Emergency Contraception Pill in India: Challenges and Opportunities

Background:

Emergency Contraception Pill (ECP) is an essential intervention to prevent unwanted pregnancies. However, its use has remained low due to various barriers including reservations among medical fraternity.

Materials and Methods:

This paper presents findings on barriers to ECP''s easy access for potential users from (i) a cross-sectional survey of providers'' attitudes, beliefs, and practices and interviews with key opinion leaders, (ii) three consultations organized by Population Council with policymakers and public health experts, and (iii) evidence from scientific literature.

Results:

The major barriers to easy access of ECP include misconceptions and reservations of providers (disapproval of ECP provision by CHWs, opposition to its being an OTC product, and myths, misconceptions, and moral judgments about its users) including influential gynecologists.

Conclusion:

For mainstreaming ECP, the paper recommends educational campaign focusing on gynecologists and CHWs, relaxing restrictive policy on advertisement of ECP, involving press media and strengthening supply chain to ensure its regular supply to ASHA (CHW).     

A comparison of enoxaparin with unfractionated heparins in patients with coronary heart disease in an emergency department in rural South Indian tertiary care teaching hospital

Aim:Antithrombotic therapy with heparin plus antiplatelets reduces the rate of ischemic events in patients with coronary heart disease. Low molecular weight heparin has a more predictable anticoagulant effect than standard unfractionated heparin, is easier to administer, does not require monitoring and is associated with less ADRs. The purpose of the present study was to evaluate and compare the clinical and cost outcomes of Enoxaparin with a standard unfractionated heparin in patients with coronary heart disease.Results:Compared to unfractionated heparin group of patients, the average prothrombin time was significantly higher (P < 0.0001) whereas hypokalemia was significantly lower (P < 0.02) in enoxaparin group of patients. Even though recurrence of angina and ADRs such as bleeding, nausea, headache and sudden cough occurred less frequently in the enoxaparin group of patients compared to unfractionated heparin group of patients, the differences were not significant.Conclusions:Antithrombotic therapy with enoxaparin plus aspirin was safer and more effective than unfractionated heparin plus aspirin, in reducing the incidence of ischemic events in patients with unstable angina or myocardial infarction in the early phase.KEY WORDS: Anticoagulant, coronary heart disease, enoxaparin, safety, and efficacy, unfractionated heparin