A EPC Approach to the Residual Water in Erythrocytes

A novel approach has been developed to determine the amount of residual water in human erythrocyte at room temperature by electronic particle counter. Nacl solutions of 13 osmolalities were prepared and the equilibrium cell volumes in which were measured one by one. The isotonic volume, Vo, was obtained under the isotonic condition. The mean RBC volumes of 5 donors at each osmolality were fitted according to Boyle van‘t Hoff relationship, and the osmotically inactive volume, Vb, of erythrocyte was then determined. The results show that Vb＝50% Vo. More importantly, the final cell volume with regard to the solution of the highest concentration found to be kept at about 0. 5 V0. The difference between these two volumes is unconspicuous. According to the published data that non-water volume of human erythrocyte is about 28.3% of its isotonic volume, residual water of human erythrocyte can be gained by subtracting Vdry from Vf, that is Vrw----21.7% Vo Then it was concluded that the residual water of human lays in 2 states, one is bound water, and the other is free water.     

Can the gracilis be used to replace the anterior cruciate ligament in the knee? A cadaver study

PurposeThe purpose of this study was to evaluate whether a four-strand gracilis-only graft can be used in anterior cruciate ligament (ACL) reconstruction.Study designCadaver study.MethodsThis study involved 16 cadaver knees. The length and diameter of the native ACL were measured in each one. The same measurements were performed on a four-strand graft of the gracilis only, the semitendinosus only and both tendons. Student's t-test was used to compare the various conditions.ResultsThe average diameter of the G4 construct was 0.07 mm greater (1%) than the native ACL (p = 0.044). The average cross-sectional area of the G4 construct was 1.2 mm² greater (3.9%) than the native ACL (p = 0.049). The G4 was on average 38.9 mm longer than the intra-articular portion of the ACL (p < 0.001).ConclusionA four-strand gracilis construct meets the anatomical specifications for use as an ACL reconstruction graft. By using the gracilis only, the morbidity associated with harvesting the gracilis and semitendinosus tendons should be reduced. Further studies must be performed to compare the biomechanical properties of this graft with other graft types and also to evaluate how this four-strand gracilis graft behaves in a clinical setting.     

The susceptibility of the kidney to alternative pathway activation—A hypothesis

The glomerulus is often the prime target of dysregulated alternative pathway (AP) activation. In particular, AP activation is the key driver of two severe kidney diseases: atypical hemolytic uremic syndrome and C3 glomerulopathy. Both conditions are associated with a variety of predisposing molecular defects in AP regulation, such as genetic variants in complement regulators, autoantibodies targeting AP proteins, or autoantibodies that stabilize the AP convertases (C3- and C5-activating enzymes). It is noteworthy that these are systemic AP defects, yet in both diseases pathologic complement activation primarily affects the kidneys. In particular, AP activation is often limited to the glomerular capillaries. This tropism of AP-mediated inflammation for the glomerulus points to a unique interaction between AP proteins in plasma and this particular anatomic structure. In this review, we discuss the pre-clinical and clinical data linking the molecular causes of aberrant control of the AP with activation in the glomerulus, and the possible causes of this tropism. Based on these data, we propose a model for why the kidney is so uniquely and frequently targeted in patients with AP defects. Finally, we discuss possible strategies for preventing pathologic AP activation in the kidney.     

Infant Rodent Ultrasounds – A Gate to the Understanding of Sound Communication

Components of the communication system between infant and adult rodents based on ultrasonic vocalizations (USVs) of infants are analyzed. USVs are most often emitted from a pup lost outside the nest in response to changes of: (i) body temperature, (ii) contact with adults/littermates, (iii) handling, and (iv) smell. These changes modulate the state of arousal and the emotional/motivational states and, as a result, USVs are produced. Acoustic properties of USVs seem to reflect the degrees of changes in arousal and emotion/motivation. Adult rodents are aroused by perceiving the USVs, locate the sender and show a phonotaxic approach to the sender. Acoustic properties of USVs in the frequency and time domains are described based on which adult rodents discriminate the USVs from other ultrasounds and take the USVs or adequate models of them as preferred goals of their phonotaxic approach. The preferred approach to adequate USVs is modulated by emotions/motivations, the sex of the receiver, hormonal states, experience with pups and neurotransmitter systems of the brain. The phonotaxis can be understood as the appetitive component of a pup-caring instinct. The consummatory act of the instinct is the retrieval of the lost pup. This retrieval is independent of USV presence, but it closes the communication loop activated by the emission of USVs. Communication with USVs can be used as a tool to investigate genetic and brain mechanisms of behavioral control.     

Infectious atherosclerosis: Is the hypothesis still alive? A clinically based approach to the dilemma

Among the multiple factors involved in the pathophysiology of heart disease, infections have been proposed to play a role in atherosclerosis with most of the available evidence implicating Chlamydia pneumonia, influenza virus and Mycoplasma pneumoniae. Based on a model case presentation, we speculate that in the absence of traditional risk factors and in the context of an ongoing respiratory infection caused by a pro-inflammatory pathogen (M. pneumoniae) along with a past positive serologic history for potentially proven atherogenic microorganism (C. pneumoniae) and infection may elicit potentially pathogenic events on vascular wall cells and leukocytes of atheromatous lesions, supporting the hypothesis that such infections may potentiate atherosclerotic cardiovascular disease (CVD).     

Is the communicative behavior of GPs during the consultation related to the diagnosis? A cross-sectional study in six European countries

This study explores the relation between the diagnosis made by the general practitioner (GP) and his or her communicative behavior within a consultation, by means of the analysis of 2095 videotaped consultations of 168 GPs from six countries participating in the Eurocommunication study. The doctors' diagnoses were coded into ICPC chapters and merged into seven clinically relevant diagnostic clusters. The communicative behavior was gauged by means of the Roter interaction analysis system (RIAS). We found the most important differences for consultations about psychosocial problems as compared to all other diagnostic categories. In these consultations, doctors show more affective behavior, are more concerned about having a good relationship with their patients, ask more questions and give less information than in other consultations. The percentages of utterances in the other diagnostic categories were pretty similar. The communicative behavior of doctors reflects a global pattern in every consultation. This pattern is the most stable for affective behavior (social talk, agreement, rapport building and facilitation). Within instrumental behavior (the other categories), the directions and the information the doctor gives are adapted to the problems presented.     

Is the transtheoretical model and motivational interviewing approach applicable to the treatment of eating disorders? A review

Research in eating disorders is reviewed examining the (1) utility of the Transtheoretical Model in predicting outcome, and (2) efficacy of Motivational Interviewing (MI). There were promising results showing significant relationships between initial stage of change and treatment outcome related to eating pathology (not including purging), body mass index, and some aspects of psychopathology. Of those treatment studies utilising a control group, there was little indication that using MI conferred significant treatment benefit, with the exception of improving motivation and binge eating for people with binge eating disorder and bulimia nervosa. Overall the content of the studies varied greatly with relation to: stage of change and outcome measures, format of MI, diagnostic groupings, age of participants, utilisation of other adjunctive treatments, sample size, presence of follow-up assessments, and study design. Few of the 9 studies examining the efficacy of MI could be considered to have robust methodology. It is recommended that future research using the Transtheoretical Model to predict outcome adopt more uniform methodology so that we can more specifically determine its applicability, and that well-designed treatment studies in eating disorder populations be conducted so that we develop a stronger evidence base from which to decide whether MI confers benefit.     

A follow-up to the medical education issue of the JNMA: our political irrelevancy,or what?

It just so happened that in the inaugural medical education issue of the September 2005 Journal of the National Medical Association, we interviewed Dr. J.W. Carmichael. Xavier University of Louisiana is the only black Catholic University in the United States and is located in the recently devastated city of New Orleans. As many of you may recall, Carmichael is the director of Xavier University's premedicine program. The university's premedicine program has supplied American medical schools with more than 90 black students per year for the last decade. It has been a crucial lifeline in the supply of African-American physicians and pharmacists in the United States. Just to get an idea of the importance of the Xavier program, please review a copy of the September issue of the JNMA and the articles related to student education.     

Taking the biscuit? A discursive approach to managing diet in type 2 diabetes

Adopting and maintaining a healthy diet is pivotal to diabetic regimens. Behavioural research has focused on strategies to modify/maintain healthy behaviours; thus 'compliance' and 'noncompliance' are operationalized by researchers. In contrast, discursive psychology focuses on the actions different accounts accomplish--in this case regarding diets. Using thematic discourse analysis, we examine dietary management talk in repeat-interviews with 40 newly diagnosed type 2 diabetes patients. Women in our study tended to construct dietary practices as an individual concern, while men presented food consumption as a family matter. Participants accounted for 'cheating' in complex ways that aim to accomplish, for instance, a compliant identity. Discursive psychology may facilitate fluidity in our understandings of dietary management, and challenge fixed notions of 'compliant' and 'non-compliant' diabetes patients.     

A systems toxicology approach to the surface functionality control of graphene–cell interactions

The raised considerable concerns about the possible environmental health and safety impacts of graphene nanomaterials and their derivatives originated from their potential widespread applications. We performed a comprehensive study about biological interaction of grapheme nanomaterials, specifically in regard to its differential surface functionalization (oxidation status), by using OMICS in graphene oxide (GO) and reduced graphene oxide (rGO) treated HepG2 cells. Differential surface chemistry (particularly, oxidation – O/C ratio) modulates hydrophobicity/philicity of GO/rGO which in turn governs their biological interaction potentiality. Similar toxic responses (cytotoxicity, DNA damage, oxidative stress) with differential dose dependency were observed for both GO and rGO but they exhibited distinct mechanism, such as, hydrophilic GO showed cellular uptake, NADPH oxidase dependent ROS formation, high deregulation of antioxidant/DNA repair/apoptosis related genes, conversely, hydrophobic rGO was found to mostly adsorbed at cell surface without internalization, ROS generation by physical interaction, poor gene regulation etc. Global gene expression and pathway analysis displayed that TGFβ1 mediated signaling played the central role in GO induced biological/toxicological effect whereas rGO might elicited host-pathogen (viral) interaction and innate immune response through TLR4–NFkB pathway. In brief, the distinct biological and molecular mechanisms of GO/rGO were attributed to their differential surface oxidation status.