Anatomical variants of the basal vein of Rosenthal: prevalence in idiopathic subarachnoid hemorrhage

Background

Spontaneous, non traumatic subarachnoid hemorrhage (SAH) is a significant clinical problem that occurs most commonly as a result of aneurysm rupture. In approximately 15 % of cases, nor aneurysm or other vascular malformation can be identified by cerebral angiography as origin of the hemorrhage, and these are commonly defined as idiopathic SAH (ISAH). Because of the negative angiography, limited extension of the bleeding with prevalent prepontine pattern and the benign prognosis, the venous causes has been preferred rather than the arterial ones. In the literature recent studies have suggested a possible contribution by primitive variants of Basal vein of Rosenthal (BVR) in its the pathogenesis of ISAH, commonly grouped according Watanabe classification (type A, B and C). In this paper we evaluated the prevalence of anatomical variants of BVR in ISAH.

Methods

Venous drainage at angiography was retrospectively analyzed in 40 patients with ISAH and in 40 with unruptured aneurysms as controls.

Results and conclusions

Previous studies displayed a significant prevalence of BVR type C variants in ISAH. Conversely in our study we recognized variant B as prevalent, in which the BVR bifurcates to drain anteriorly into the uncal vein and posteriorly into the Galenic system. Similarly to variant C (in which the BVR drains via perimesencephalic “bridging” veins into cavernous, sphenoparietal, petrosal sinus or directly into transverse sinus) also variant B might be subjected to those stress mechanisms and intrinsic system ‘fragility’ and for reasons yet to determine, sets off a consequent hemorrhage with clinical and radiological features typical of ISAH.     

Platelet Distribution Width and Increased D-Dimer at Admission Predicts Subsequent Development of ARDS in COVID-19 Patients

In the current pandemic of coronavirus disease (COVID-19), the identification of the patients admitted with severe infection–who are disposed to a high risk of acute respiratory distress syndrome (ARDS) development, is of a major significance for the determination of the appropriate therapeutic strategy. Laboratory records in admission were retrospectively reviewed from 493 cases of severe COVID-19 divided into two groups: Group 1 with ARDS and Group 2 without ARDS. The platelet distribution width (PDW) difference between Group 1 and Group 2 is significant–15.10 ± 2.08 fl for those who developed ARDS versus 12.94 ± 2.12 fl for those without ARDS. The sensitivity and the specificity of this parameter is lower than that of D-dimer. After grouping of the PDW values into intervals and combining them with the rate of increase in D-dimer (D-PDWf index) to form a forecasting index, a significant increase in the specificity and sensitivity of the two parameters is identified–area under the ROC curve (AUC) is 0.874 for D-PDWf index, with respective AUC for PDW 0.768 and AUC for D-dimer 0.777. Conclusion: PDW is a significant predictive parameter at admission for subsequent development of ARDS in patients, with increased significance in combination with the degree of increase in D-dimer.     

Design,Synthesis, and Antimycobacterial Activity of Novel Theophylline‐7‐Acetic Acid Derivatives With Amino Acid Moieties

The theophylline‐7‐acetic acid (7‐TAA) scaffold is a promising novel lead compound for antimycobacterial activity. Here, we derive a model for antitubercular activity prediction based on 14 7‐TAA derivatives with amino acid moieties and their methyl esters. The model is applied to a combinatorial library, consisting of 40 amino acid and methyl ester derivatives of 7‐TAA. The best three predicted compounds are synthesized and tested against Mycobacterium tuberculosis H37Rv. All of them are stable, non‐toxic against human cells and show antimycobacterial activity in the nanomolar range being 60 times more active than ethambutol.     

Pharmacokinetic and pharmacodynamic approach for comparing two therapeutic regimens using amikacin.

The efficiencies of two dosage schedules of amikacin (2 x 10 mg/kg of body weight per 24 h and 1 x 20 mg/kg/24 h intramuscularly for 5 days) against Pseudomonas aeruginosa sepsis in rabbits were compared. Blood samples were drawn at various times after the first application, and amikacin concentrations in serum were assayed microbiologically. The dynamics of the bactericidal effect of amikacin was simulated in vitro with the same strain of P. aeruginosa. No regrowth was found with the 20-mg/kg dose when the bacterial inoculum was in contact with experimental and theoretically predicted serum amikacin concentrations. The killing effect was present even when the drug levels decreased considerably below the MIC. The interrelationship between simulated amikacin concentrations in serum and the corresponding average killing rates was described appropriately by the standard Emax model. The higher amikacin dose performed its bacterial effect faster and the drug persisted longer in the blood. The two amikacin regimens were therapeutically equivalent, but the once-daily schedule had some advantages over the twice-daily drug administration which became evident when both the pharmacokinetic and the pharmacodynamic parameters of the drug were considered.     

Sagittal fresh blood imaging with interleaved acquisition of systolic and diastolic data for improved robustness to motion

Purpose:

To improve robustness to patient motion of “fresh blood imaging” (FBI) for lower extremity noncontrast MR angiography.

Methods:

In FBI, two sets of three‐dimensional fast spin echo images are acquired at different cardiac phases and subtracted to generate bright‐blood angiograms. Routinely performed with a single coronal slab and sequential acquisition of systolic and diastolic data, FBI is prone to subtraction errors due to patient motion. In this preliminary feasibility study, FBI was implemented with two sagittal imaging slabs, and the systolic and diastolic acquisitions were interleaved to minimize sensitivity to motion. The proposed technique was evaluated in volunteers and patients.

Results:

In 10 volunteers, imaged while performing controlled movements, interleaved FBI demonstrated better tolerance to subject motion than sequential FBI. In one patient with peripheral arterial disease, interleaved FBI offered better depiction of collateral flow by reducing sensitivity to inadvertent motion.

Conclusions:

FBI with interleaved acquisition of diastolic and systolic data in two sagittal imaging slabs offers improved tolerance to patient motion. Magn Reson Med, 2013. © 2013 Wiley Periodicals, Inc.     

Remote FLS testing in the real world: ready for “prime time”

Introduction

Maintaining the existing FLS test centers requires considerable investment in human and financial resources. It can also be particularly challenging for those outside of North America to become certified due to the limited number of international test centers. Preliminary work suggests that it is possible to reliably score the FLS manual skills component remotely using low-cost videoconferencing technology. Significant work remains to ensure that testing procedures adhere to standards defined by SAGES for this approach to be considered equivalent to standard on-site testing.

Objective

To validate the integrity and validity of the FLS manual skills examination administered remotely in a real-world environment according to FLS testing protocols and to evaluate participants’ experience with the setting.

Methods

Individuals with various levels of training from the University of Toronto completed a pre- and a post-test questionnaire. Participants presented to one of the two FLS testing rooms available for the study, each connected via Skype to a separate room with a FLS proctor who administered and scored the test remotely (RP). An on-site proctor (OP) was present in the room as a control. An invigilator was also present in the testing room to follow directions from the RP and ensure the integrity of test materials.

Results

Twenty-one participants were recruited, and 20 completed the test. There was no significant difference between scores by RP and OP. Interrater reliability between the RP and OP was excellent. One critical error was missed by the RP, but this would not have affected the test outcome. Participants reported being highly satisfied.

Conclusion

We demonstrate that proctors located remotely can administer the FLS skills test in a secure and reliable fashion, with excellent interrater reliability compared to an on-site proctor. Remote proctoring of the FLS examination could become a strategy to increase certification rates while containing costs.

     

Whole grain intake in relation to body weight: from epidemiological evidence to clinical trials

This viewpoint aims to 1) review the available scientific literature on the relationship between whole grain consumption and body weight regulation; 2) evaluate the potential mechanisms whereby whole grain intake may help reduce overweight and 3) try to understand why epidemiological studies and clinical trials provide diverging results on this topic. All the prospective epidemiological studies demonstrate that a higher intake of whole grains is associated with lower BMI and body weight gain. However, these results do not clarify whether whole grain consumption is simply a marker of a healthier lifestyle or a factor favoring "per se" lower body weight. Habitual whole grain consumption seems to cause lower body weight by multiple mechanisms such as lower energy density of whole grain based products, lower glycemic index, fermentation of non digestible carbohydrates (satiety signals) and finally by modulating intestinal microflora. In contrast with epidemiological evidence, the results of few clinical trials do not confirm that a whole grain low-calorie diet is more effective in reducing body weight than a refined cereal diet, but their results may have been affected by small sample size or short duration of the intervention. Therefore, further intervention studies with adequate methodology are needed to clarify this question. For the time being, whole grain consumption can be recommended as one of the features of the diet that may help control body weight but also because is associated with a lower risk to develop type 2 diabetes, cardiovascular diseases and cancer.