Effect of hormone replacement therapy on cardiac autonomic modulation

Objective

To investigate the effects of hormone replacement therapy (HRT) on heart rate variability (HRV) in healthy postmenopausal women.

Methods

Two groups were evaluated: group 1 (G1): 20 women not undergoing HRT (60 ± 5.89 years), group 2 (G2): 20 women undergoing HRT (59 ± 5.70 years). The HRTs involved were either conjugated equine estrogen with or without medroxyprogesterone, synthetic estrogen hormone, estradiol associated with norethisterone acetate or isoflavonoids. Electrocardiogram was recorded in the supine position for 10 min. Spectral analysis included low and high frequencies in absolute (LF and HF) and normalized units (LFnu and HFnu), which are predominantly cardiac sympathetic modulation (CSM) and cardiac vagal modulation (CVM) indicators, respectively. The LF/HF ratio was also calculated. Symbolic analysis involved the following indexes: 0V % (CSM indicator), 1V % (CSM and CVM indicators), 2LV % (predominantly CVM indicator) and 2UV % (CVM indicator). Shannon and conditional entropies were also calculated.

Results

Spectral analysis demonstrated that HRT affected HRV. LF, LFnu and LF/HF ratio were higher (showing increased CSM), while HFnu was lower (representing decreased CVM) in G2 than in G1. Correlations between complexity indices and HFnu were significant and positive only in G1.

Interpretation

Women undergoing HRT presented higher CSM and lower CVM than those who were not. Moreover, the expected positive relationship between CVM and complexity of HRV was found only in control group, thus indicating that CVM in women under therapy drop below a minimal value necessary to the association to become apparent, suggesting an unfavorable cardiac autonomic modulation in spite of HRT.     

Does Achilles Tendon Cross Sectional Area Differ after Downhill,Level and Uphill Running in Trained Runners?

In this study we examined how hill running affects the Achilles tendon, a common location for injuries in runners. Twenty females ran for 10 min on each of three randomly ordered grades (-6%, 0 and +6%) at speeds selected to match the metabolic rates. Achilles tendon (AT) cross-sectional area (CSA) was imaged using Doppler ultrasound and peak vertical forces were analyzed using an instrumented treadmill. A metabolic cart and gas analyzer ensured a similar metabolic cost across grades. Data were analyzed using a forward selection regression. Results showed similar decreases in AT CSA from pre- to post-run for all three conditions of ~5 to 7% (p = 0.0001). Active peak vertical forces were different across grades (p = 0.0001) with the largest occurring during downhill running and smallest during uphill running. Since changes in AT CSA were not different between grades, each form of running appears equal and acceptable in regards to how the Achilles tendon reacts. That is, the results suggest that the Achilles tendon is affected by downhill, level, and uphill running and a decrease in CSA appears to be a normal response.

Key Points

• Downhill (- 6%), level and uphill (+ 6%) running at different speeds each caused a statistically significant decrease in the Achilles tendon cross-sectional area in healthy, trained runners.
• The magnitude of change in Achilles tendon cross-sectional area did not differ between grades when metabolic cost of running was matched.
• Downhill running resulted in the largest peak vertical force, while uphill running resulted in the smallest.

Key words: Doppler ultrasound imaging, cross-sectional area, peak vertical force     

DETECTION OF VIRULENCE GENES IN ENVIRONMENTAL STRAINS OF Vibrio cholerae FROM ESTUARIES IN NORTHEASTERN BRAZIL

The objectives of this study were to detect the presence of Vibrio cholerae in tropical estuaries (Northeastern Brazil) and to search for virulence factors in the environmental isolates. Water and sediment samples were inoculated onto a vibrio-selective medium (TCBS), and colonies with morphological resemblance to V. cholerae were isolated. The cultures were identified phenotypically using a dichotomous key based on biochemical characteristics. The total DNA extracted was amplified by PCR to detect ompW and by multiplex PCR to detect the virulence genes ctx, tcp, zot and rfbO1. The results of the phenotypic and genotypic identification were compared. Nine strains of V. cholerae were identified phenotypically, five of which were confirmed by detection of the species-specific gene ompW. The dichotomous key was efficient at differentiating environmental strains of V. cholerae. Strains of V. cholerae were found in all four estuaries, but none possessed virulence genes.     

USE OF LOPINAVIR/RITONAVIR ASSOCIATED WITH ERGOTAMINE RESULTING IN FOOT AMPUTATION: BRIEF COMMUNICATION

A 32-year-old female, was diagnosed in 2004 with a C1 HIV1 infection, using zidovudine/lamivudine 300/150 mg BID and lopinavir/ritonavir 400/100 mg BID, in addition to prophylaxis with trimethoprim-sulfamethoxazole 800/160 mg QD, but no prophylaxis with macrolide antibiotics. The patient presented with a severe headache and was prescribed two capsules of the anti-migraine drug Ormigrein™, which contained ergotamine tartrate 1 mg, caffeine 100 mg, paracetamol 220 mg, hyoscyamine sulfate 87.5 mcg, and atropine sulfate 12.5 mcg. Afterwards she was prescribed one capsule of Ormigrein every 30 minutes for a total of six capsules a day. The patient took the medication as prescribed but developed a pain in her left ankle three days later, which evolved to the need for amputation.     

Immunolocalization of markers for bone formation during guided bone regeneration in osteopenic rats

Objective

The aim of this paper was to evaluate the repair of onlay autogenous bone grafts covered or not covered by an expanded polytetrafluoroethylene (e-PTFE) membrane using immunohistochemistry in rats with induced estrogen deficiency.

Material and Methods

Eighty female rats were randomly divided into two groups: ovariectomized (OVX) and with a simulation of the surgical procedure (SHAM). Each of these groups was again divided into groups with either placement of an autogenous bone graft alone (BG) or an autogenous bone graft associated with an e-PTFE membrane (BGM). Animals were euthanized on days 0, 7, 21, 45, and 60. The specimens were subjected to immunohistochemistry for bone sialoprotein (BSP), osteonectin (ONC), and osteocalcin (OCC).

Results

All groups (OVX+BG, OVX+BMG, SHAM+BG, and SHAM+BMG) showed greater bone formation, observed between 7 and 21 days, when BSP and ONC staining were more intense. At the 45-day, the bone graft showed direct bonding to the recipient bed in all specimens. The ONC and OCC showed more expressed in granulation tissue, in the membrane groups, independently of estrogen deficiency.

Conclusions

The expression of bone forming markers was not negatively influenced by estrogen deficiency. However, the markers could be influenced by the presence of the e-PTFE membrane.     

Staying the Surgeon’s Hand: Role of Percutaneous Catheter Drainage in Acute Necrotising Pancreatitis

Introduction

Acute necrotising pancreatitis (NP) is associated with high morbidity and mortality. Patients with infected pancreatic necrosis (IPN) require some form of intervention in addition to medical management. Although there is no accepted consensus, it is generally agreed that the infected non-vital solid tissue needs to be removed in order to control the sepsis. The results of early surgery have not been encouraging, compared with cases where surgery was delayed or avoided. The placement of percutaneous catheter drains in such a situation helps to decrease the systemic inflammatory response and reverse organ dysfunction.

Aims and objectives

The aim of this study was to review retrospectively the results of percutaneous catheter drainage (PCD) in patients with acute NP requiring intervention.

Materials and methods

A retrospective study was conducted of patients presenting with acute NP from March 2012 to June 2015. Demographic, clinical, and perioperative information was retrieved from the medical records. The patients were initially managed in the intensive care unit (ICU) with goal-directed therapy and organ support where indicated. The patients with IPN and few with sterile pancreatic necrosis (SPN) who had persistent organ failure or whose clinical condition was deteriorating despite adequate medical support were subjected to some form of intervention. All the patients requiring PCD or surgical intervention were included in this study. These patients were divided into 3 groups based on the type of intervention: a) PCD only, b) PCD followed by surgical intervention, and (c) surgery alone. The outcome in these 3 groups was analyzed and the factors associated with failure of PCD were identified. In addition, the complications of SPN were investigated.

Results

The records were reviewed of 46 patients diagnosed with acute NP, of which 23 required PCD or surgical intervention and were included in this study. The mean acute physiology and chronic health (APACHE II) score of these patients was 10.6 ± 3.45, while the mean bedside index of severity in acute pancreatitis (BISAP) score was 4.47 ± 0. 53. On contrast enhanced computed tomography (CECT) scan of the abdomen, 39% of the patients had >50% necrosis, with a mean CT severity index (CTSI) of 8.1 ± 1.9. Of the 21 patients treated initially with PCD, a step-up approach was applied in 8 patients, because of failure of PCD. The mean duration from admission to intervention was 19.5 days. A mean of 2.4 pigtail catheters were placed in each patient. Additional drains were placed in 3 patients. The duration of PCD ranged from 20 to 124 days. The mean ICU stay was 14.3 ± 3.2 days and the mean hospital stay was 35.8 ± 7.4 days. Post-intervention complications were recorded in 11 (47.8%) patients, of which 2 patients with PCD developed an external pancreatic fistula and 2 had bleeding. The mortality rate was 26% (6 patients).

Conclusion

PCD is a feasible and successful modality of treatment for acute NP requiring intervention. With the use of PCD, surgical necrosectomy may be completely avoided or delayed until the condition of the patient is stable enough to sustain surgery.

     

Structural and Optical Characterization of Mechanochemically Synthesized CuSbS2 Compounds

One of the areas of research on materials for thin-film solar cells focuses on replacing In and Ga with more earth-abundant elements. In that respect, chalcostibite (CuSbS₂) is being considered as a promising environmentally friendly and cost-effective photovoltaic absorber material. In the present work, single CuSbS₂ phase was synthesized directly by a short-duration (2 h) mechanochemical-synthesis step starting from mixtures of elemental powders. X-ray diffraction analysis of the synthesized CuSbS₂ powders revealed a good agreement with the orthorhombic chalcostibite phase, space group Pnma, and a crystallite size of 26 nm. Particle-size characterization revealed a multimodal distribution with a median diameter ranging from of 2.93 μm to 3.10 μm. The thermal stability of the synthesized CuSbS₂ powders was evaluated by thermogravimetry and differential thermal analysis. No phase change was observed by heat-treating the mechanochemically synthesized powders at 350 °C for 24 h. By UV-VIS-NIR spectroscopy the optical band gap was determined to be 1.41 eV, suggesting that the mechanochemically synthesized CuSbS₂ can be considered suitable to be used as absorber materials. Overall, the results show that the mechanochemical process is a viable route for the synthesis of materials for photovoltaic applications.