Diurnal variations of cardiac rhythm,arterial pressure,and urinary catecholamines in borderline and established essential hypertension

Ambulatory continuous ECG and arterial pressure (BP) were recorded simultaneously (Delmar Avionics Pressurometer II) for 24 hours in 13 age-matched normotensive subjects, 11 patients with borderline hypertension (HBP), and in 10 patients with uncomplicated established essential HBP. Urinary concentrations of epinephrine, norepinephrine, and dopamine were simultaneously collected over four successive 4-hour periods and one 8-hour period. Prevalence and total number of ventricular and supraventricular ectopic beats was low and not affected by arterial BP. Twenty-four-hour heart rate (HR) and 4-hourly excretion of epinephrine, norepinephrine, and dopamine were comparable between normotensive and HBP persons and no correlation between urinary catecholamines and arterial BP (systolic, diastolic, or mean), HR, or prevalence of ectopic beats was found in any of the three groups or in the total study population. We conclude that HBP patients without ECG evidence of left ventricular hypertrophy do not have a higher prevalence of supraventricular or ventricular ectopic beats. Urinary catecholamines are not related to circadian fluctuations or variability in arterial BP, HR, or prevalence of ectopic beats.     

Regulation of dopamine- and adenosine-dependent adenylate cyclase systems of chicken embryo retina cells in culture.

We have obtained evidence that receptor-stimulated adenylate cyclase activity [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] is regulated physiologically in both embryonic and mature neurons. In a series of experiments using cultured retina cells from chicken embryos, we found that dopamine-sensitive adenylate cyclase activity spontaneously desensitized as cultures differentiated. The cellular response to dopamine reached a maximum after 5 days in culture and then decreased to 40% during the next 5 days. This spontaneous desensitization appeared to be caused by functional dopaminergic transmission because it could be blocked by the dopamine antagonist haloperidol. The ability of added dopamine at 100 microM to cause near-complete desensitization is consistent with this conclusion. Pharmacologically induced desensitization required 31 hr for maximal effect and was half-maximal at 1-10 microM dopamine. Analogous desensitization of the adenosine-dependent adenylate cyclase system also was noted. When dopamine was removed from the medium of chronically treated cultures, cells resensitized to subsequent stimulation at a very slow rate. Resensitization likely depended on replacement of dopamine receptors because chronic dopamine treatment caused the disappearance of binding sites for the ligand [3H]spiroperidol. In a second series of experiments, using hatched animals, we found that similar regulation of dopamine receptor binding sites and activity could be elicited by manipulation of environmental light, a treatment thought to influence dopaminergic transmission. Retinas from animals in constant light had less specific [3H]spiroperidol binding (35 fmol/mg of protein) than did retinas from animals in constant darkness (66 fmol/mg of protein) and made less cAMP in response to added dopamine. Our results indicate that regulation of the dopamine receptor system begins early in development and continues to function in mature synapses.     

The initial phase of graft‐versus‐host disease is associated with a decrease of CD4+CD25+ regulatory T cells in the peripheral blood of patients after allogeneic stem cell transplantation

The mechanisms that induce and control the alloimmune inflammation of graft‐versus‐host disease (GvHD) after allogeneic stem cell transplantation (allo‐SCT) are still incompletely understood. In the murine system, GvHD can be suppressed by CD4⁺CD25⁺ regulatory T cells (TREG), which are generally involved in the suppression of inflammatory reactions. A disruption of the homeostasis between TREG and conventional T cells might therefore be associated with the inflammatory reactions of GvHD. We repetitively measured the frequency of TREG in the peripheral blood of 29 patients within the first 71–373 days after allo‐SCT and correlated the results with the clinical course. We demonstrate that the initial phase of GvHD is associated with a significant reduction of TREG in the peripheral blood, while at later stages and during intensified immunosuppressive therapy, increased numbers of TREG appear. These results might indicate a pathogenic role for reduced numbers of TREG in the induction of human GvHD.     

Burkholderia pseudomallei Isolates in 2 Pet Iguanas,California, USA

Burkholderia pseudomallei, the causative agent of melioidosis, was isolated from abscesses of 2 pet green iguanas in California, USA. The international trade in iguanas may contribute to importation of this pathogen into countries where it is not endemic and put persons exposed to these animals at risk for infection.Key words: Burkholderia pseudomallei, iguana, zoonoses, abscess, melioidosis, bacteriaBurkholderia pseudomallei, a gram-negative bacterium, is the causative agent of melioidosis. Melioidosis is endemic in countries in Southeast Asia and in northern Australia, and has been sporadically reported from Central and South America (1). In the United States, most case-patients have traveled to disease-endemic areas (2).B. pseudomallei infection occurs through direct cutaneous inoculation with soil or water containing B. pseudomallei and through ingestion or inhalation of aerosolized bacteria. In humans, the incubation period is typically 1–21 days, but some patients demonstrate clinical signs years after exposure (1). Acute melioidosis can manifest as a severe pneumonia and septicemia, with death rates >40% in countries where access to medical care is limited. In chronic melioidosis, abscesses occur in various organs, including the lungs, liver, spleen, and cutaneous sites (1,3). In animals, abscesses and acute illness are common (4).B. pseudomallei is classified by US federal agencies as a tier 1 select agent. Tier 1 agents are believed to pose the greatest threat for deliberate misuse and potential harm to public health. Multiple regulations restrict access to these agents and reduce the risk of their release from secure settings (5). Infection is generally diagnosed by culture. Commercially available bacterial identification systems may provide initial identification; however, B. pseudomallei may be misidentified by some systems (6). Other identification tests are available, including PCR and antigen detection; these are not commonly used outside disease-endemic regions (3,7,8).     

Lateral ligament reconstruction with allograft in patients with severe chronic ankle instability

Introduction

Chronic ankle instability is a condition of perception of giving way and persistent pain usually following multiple ankle sprains. In case of severe joint laxity, surgical treatment with reconstruction of the lateral ligamental complex is recommended. The aim of this study was to evaluate the functional outcome of patients treated with lateral ligament reconstruction with allograft for severe chronic lateral ankle instability.

Materials and methods

We performed a retrospective cohort study of ten patients who underwent allograft external non-anatomic ligamentoplasty for severe chronic lateral ankle instability between 2009 and 2011, with an average follow-up of 16.3 months (SD 8.2). Median age at surgery was 29 years (range 25–35). All patients presented both ATFL and CFL lesion. Patients were evaluated using American Orthopaedic Foot and Ankle Society score, Karlsson–Peterson score, Tegner activity level, Sefton stability scale, and objective examination comprehending range of motion, anterior drawer sign and talar tilt test. Telos stress equipment was used for pre- and post-operative radiographic laxity testing.

Results

Follow-up examination at an average of 16.3 months (SD 8.2) after surgery showed significant improvement of all variables compared to pre-operative values (p < 0.001). Most patients rated their outcome as good/excellent. Telos stress radiographs documented improvement in joint stability.

Conclusions

Lateral ligament reconstruction with allograft represents a valid treatment option in patients with severe chronic lateral ankle instability.     

Impact of multidisciplinary hip fracture program on timing of surgery in elderly patients

Summary

The effect of patient characteristics and organizational and system factors on time to surgery were studied using Emilia Romagna Region database and hospital survey. The results showed that the implementation of a Hip Fracture Program significantly increased the probability of early surgery while single intervention had only slight effect

Introduction

The purpose of this study is to evaluate the effect of formal Hip Fracture Program (HFP) on timing of surgery in hip fracture older patients.

Methods

This is a retrospective cohort study based on Emilia Romagna administrative databases. Data on organizational and system factor were also obtained through a hospital survey. A multilevel logistic regression analysis was carried out to assess the effect of covariates on early surgery, taking into account patient level, hospital level, and trust level variability.

Results

From 1 January to 31 December 2011, 5,520 subjects over 65 years old underwent surgical repair for hip fracture in Emilia Romagna. The mean waiting time to surgery was 3.4?±?12.3 days, and the overall percentage of patients operated within 2 days was 52.2 %. In the adjusted multilevel logistic model, significant risk factors affecting the timing of surgical intervention at patient level were age, comorbidity, day of admission, and antiplatelet or warfarin therapy while no significant single variables were found at hospital level including dedicated operation theater, hospital volume, dedicated orthogeriatric beds, and geriatrician involvement. The most significant variable was the implementation of HFP at trust level that increased three times the probability of early surgery after adjusting for confounding variables (OR 3.216, 95 % CI 0.582–6.539).

Conclusions

Several modifiable organizational factors may affect the proportion of patients with hip fracture undergoing early surgery. This study suggests that the development and the implementation of an evidence-based HFP at trust level are a key point of the strategy of quality of care.     

Hippocampal shape analysis in Alzheimer's disease using functional data analysis

The hippocampus is one of the first affected regions in Alzheimer's disease. The left hippocampi of control subjects, patients with mild cognitive impairment and patients with Alzheimer's disease are represented by spherical harmonics. Functional data analysis is used in the hippocampal shape analysis. Functional principal component analysis and functional independent component analysis are defined for multivariate functions with two arguments. A functional linear discriminant function is also defined. Comparisons with other approaches are carried out. Our functional approach gives promising results, especially in shape classification. Copyright © 2013 John Wiley & Sons, Ltd.