Neurological and humoral control of blood pressure

There is a relationship between arterial blood pressure, cardiac output and vascular resistance described mathematically, that helps us to understand short-term control of blood pressure in terms of a hydraulic system. Arterial baroreceptors are specialized sensors which mediate a rapid response to sudden changes in pressure through interaction with the autonomic nervous system. This in turn influences heart rate, inotropic state and vascular tone, altering distribution of blood between arterial and venous systems, thus compensating for acute changes in total blood volume. Total blood volume is controlled predominantly by the kidney, with the renin–angiotensin–aldosterone system acting as both the ‘sensor’ of blood pressure/volume (via renin release in the juxtaglomerular apparatus) and the ‘effector’ of blood pressure/volume (via aldosterone secretion by the adrenal cortex). Overall control is shared; the baroreceptors being responsible for mediating short-term changes, and renal mechanisms determining the long-term control of blood pressure. These systems have to be adaptable in order to deal with physiological variation in the delivery of blood to tissues from rest to exercise, and with the large shifts in blood volume seen in acute haemorrhage. Pathophysiological changes in these systems lead to maladaptive responses, with systemic hypertension the most commonly seen.     

Changes in circulating lymphocytes and lymphoid tissue associated with vaccination of colostrum deprived calves

The objective of this study was to compare immunological responses and lymphoid depletion in young, colostrum deprived calves following administration of vaccines containing modified-live bovine viral diarrhea virus (BVDV). A group of calves exposed to a typical virulence non-cytopathic (ncp) BVDV-2 field strain (ncp exposed) was included to compare responses of calves receiving vaccine to responses generated against a field strain (mimicking a natural infection). A negative control group administered a placebo was used in all comparisons. All vaccines used in the study were administered per manufacturer recommendations while ncp BVDV exposed calves received 5 ml intranasally (2.5 ml/nare; 4.2 × 10⁶ TCID₅₀/ml) of the BVDV-2 field strain. Samples collected at each time point included nasal swabs for virus detection, blood samples for complete blood counts and detection of viremia, PBMCs for flow cytometric analysis, serum for virus neutralization titers, and thymus tissue at necropsy for evaluation of lymphoid depletion. A measurable neutralizing BVDV titer was observed for all treatment groups excluding the control animals, which remained negative during the study period. Virus shedding was only detected from the ncp vaccinated and ncp exposed calves. A decline from baseline was observed for peripheral lymphocyte and CD4⁺ cells for the groups receiving the adjuvanted cytopathic (cp) vaccine, the double deleted genetically modified (ddGM) vaccine, the ncp vaccine and ncp exposed calves, but not for the control group or groups receiving cp vaccines. Thymus depletion was observed for the ncp vaccine and ncp exposed calves and to a lesser extent for the ddGM vaccine calves. Collectively, these data suggest that the virus biotype, method of attenuation, presentation, and use of adjuvant will influence vaccine impacts on lymphoid tissues and the immune response. As such, multiple variables should be considered when determining costs and benefits of vaccination.     

“提壶揭盖”法治疗肛肠术后尿潴留的临床疗效

目的：观察“提壶揭盖”法治疗肛肠术后尿潴留的疗效。方法：将肛肠病术后发生尿潴留56例，采用随机数字表法进行随机分组，对照组28例仅予以肌肉注射新斯的明，治疗组在肌肉注射新斯的明的基础上使用提壶揭盖组方治疗。结果：治疗组的疗效明显高于对照组,且首次排尿时间治疗组低于对照组。结论：肛肠术后尿潴留在常规新斯的明的基础上使用提壶揭盖法可提高疗效。     

基于“血不利则为水”理论探讨乳腺癌术后上肢淋巴水肿辨治

“血不利则为水”乃《金匮要略》提出的著名论断,由此形成的“血水同治法”极大丰富了水肿病治疗。本文结合乳腺癌术后上肢淋巴水肿的临床特点,通过探讨“血不利则为水”的内涵及其病变过程中因“血不利”而致上肢肿胀的机理,认为活血利水法是防治乳腺癌术后上肢淋巴水肿的关键大法,具体应用中当结合益气行气、滋阴清热、疏肝健脾、化痰通络等法。     

基于脾主肌肉探讨苓桂术甘汤在慢性心力衰竭中的应用

中医学认为,脾气健运则肌肉丰盈有活力,脾病则肌肉萎缩不用。责之于心,则现心肌收缩无力,呈心力衰竭诸症。脾又为后天之本,气血生化之源,气血的生成、推动与心肌的濡养均与脾密切相关。临床从脾论治心力衰竭疗效确切,"脾主肌肉"可能为其重要机制之一。苓桂术甘汤健脾利水、温阳蠲饮,临床可用于对心力衰竭的治疗。     

Induction du travail après une version par manœuvres externes pour siège réussie : un sur-risque de césarienne?

Objective

To assess the effect of successful external cephalic version (ECV) on the risk of caesarean section (CS) during attempted vaginal delivery after induction of labour.

Recent advances towards the discovery of ORL-1 receptor agonists and antagonists

Since their discovery a decade ago, remarkable progress has been made toward understanding the biological function and significance of the opioid receptor-like-1 (ORL-1) receptor and its endogenous peptide ligand, nociceptin. The human nociceptin receptor, herein referred to as ORL-1, but also known as OP4 (the fourth member of opioid peptide receptor family) or nociceptin/orphanin FQ peptide (NOP) receptor, was first identified as an orphan opioid receptor with close homology to the classical μ-, κ-, and δ-opioid receptors. ORL-1 does not bind endogenous ligands of the other opioid receptors with high affinity, but instead prefers the 17 amino acid peptide nociceptin. The obvious homologies of ORL-1 to opioid receptors, and its ligand nociceptin to opioid peptide ligands, led to a period of intense investigation that resulted in a number of significant reports describing the biology of the receptor and ligand. The emerging pharmacological evidence from these reports suggests that ORL-1 agonists may be clinically useful for treatment of stress, anxiety, substance abuse (opioid and alcohol), anorexia, cachexia, cough, asthma, and possibly neuropathic pain/allodynia. The peripheral effects of nociceptin suggest that agonists may have utility in the treatment of gastrointestinal motility disorders, water retention, and hypertension. ORL-1 antagonists may be useful in enhancing cognitive function and treating locomotor disorders such as Parkinsonism. In addition to research into the fundamental biology of ORL-1 and nociceptin, noteworthy advances have been made in the discovery of new peptide and non-peptide agonists and antagonists of the ORL-1 receptor leading to a better understanding of its involvement in a variety of biological processes. This review highlights the rationale for the development of ORL-1 ligands and recent progress made by different research groups towards the development of peptidic and non-peptidic ORL-1 agonists or antagonists over the last four years. To add perspective on the commercial potential of this research area, the development status of advanced new molecules is addressed together with any pharmacological characterisation of these entities.     

Neurological and humoral control of blood pressure

There is a relationship between arterial blood pressure, cardiac output and vascular resistance which can be described mathematically, and helps us to understand the short-term control of blood pressure in the terms of a hydraulic system. The sensors in this system are the arterial baroreceptors which mediate changes in the hydraulic system though control of the autonomic nervous system, which in turn influences heart rate, inotropy and vascular tone. Altering the distribution of blood between the arterial and venous systems compensates for acute changes in total blood volume. The total blood volume is controlled predominantly by the kidney, with the renin–angiotensin–aldosterone system acting as both the ‘sensor’ of blood pressure/volume (via renin release in the juxtaglomerular apparatus) and the ‘effector’ of blood pressure/volume (via aldosterone secretion by the adrenal cortex). Overall control is shared; the baroreceptors being responsible for mediating short-term changes, and renal mechanisms determining the long-term control of blood pressure. These systems have to be adaptable in order to deal with physiological variation in the delivery of blood to tissues from rest to exercise, and with the large shifts in blood volume seen in acute haemorrhage. Pathophysiological changes in these systems lead to maladaptive responses, with systemic hypertension the most commonly seen.