Red cell membrane stiffness in iron deficiency

The purpose of this study was to characterize red blood cell (RBC) deformability by iron deficiency. We measured RBC deformability to ektacytometry, a laser diffraction method for determining the elongation of suspended red cells subjected to shear stress. Isotonic deformability of RBC from iron-deficient human subjects was consistently and significantly lower than that of normal controls. In groups of rats with severe and moderate dietary iron deficiency, RBC deformability was also reduced in proportion to the severity of iron deficiency. At any given shear stress value, deformability of resealed RBC ghosts from both iron-deficient humans and rats was lower than that of control ghosts. However, increase of applied shear stress resulted in progressive increase in ghost deformation, indicating that ghost deformability was primarily limited by membrane stiffness rather than by reduced surface area-to-volume ratio. This was consistent with the finding that iron-deficient cells had a normal membrane surface area. In addition, the reduced mean corpuscular hemoglobin concentration (MCHC) and buoyant density of the iron-deficient rat cells indicated that a high hemoglobin concentration was not responsible for impaired whole cell deformability. Biochemical studies of rat RBC showed increased membrane lipid and protein crosslinking and reduced intracellular cation content, findings that are consistent with in vivo peroxidative damage. RBC from iron-deficient rats incubated in vitro with hydrogen peroxide showed increased generation of malonyldialdehyde, an end-product of lipid peroxidation, compared to control RBC. Taken together, these findings suggest that peroxidation could contribute in part to increased membrane stiffness in iron- deficient RBC. This reduced membrane deformability may in turn contribute to impaired red cell survival in iron deficiency.     

Right Colectomy for Cancer: A Matched Comparison of Three Different Surgical Approaches

Purpose. The standard approach to right colon cancer resection is still a matter of debate and includes laparoscopy, open midline incision, or open transverse incision. We aimed this study to compare the short- and long-term results of laparoscopic right-colectomy with those provided by the open approaches. Methods. Of the 176 patients who underwent right-colectomy at our Department for nonmetastatic colon cancer, 40 patients treated by laparoscopy, 40 treated by transverse incisions, and 40 treated by midline incisions were selected and matched using the propensity score method. Short-term results included: operating time, morbidity rate, number of lymph-nodes harvested (LNH), patients’ recovery features, and costs. Long-term results included: disease-specific survivals and the rate of incisional hernias. The sub-groups were compared using t-test and Chi-square tests, whereas the Kaplan-Meier method was used to assess survivals. Results. Laparoscopies were the longer procedures, providing similar morbidity rates and LNH in comparison with the open approaches. Laparoscopy provided a faster return to oral intake and a shorter use of analgesics comparing with the midline approach; however, it showed only a minor consumption of analgesics in comparison with transverse laparotomy. There were no differences in the hospital stay and the long-term results were comparable between sub-groups. Costs analysis documented minor but not significant surgical expenses for the transverse approach. Conclusions. Laparoscopy was documented safe, with similar morbidity rates and long-term results comparing with open surgery. Laparoscopy provided better functional short-term results comparing with the midline approach, but only small differences with respect to the transverse incision approach.     

Comparison of patient reported outcomes after Triathlon? and Kinemax Plus prostheses

INTRODUCTION

The Triathlon^® (Stryker, Kalamazoo, MI, US) total knee replacement was designed to improve patient function and survivorship. The aim of this study was to determine whether the Triathlon^® prosthesis produces better patient reported outcomes than a previous design by the same manufacturer, the Kinemax Plus.

METHODS

The outcome of 233 knees of patients with a mean age of 68 years (range: 40–80 years) who received the Kinemax Plus prosthesis were compared with the outcomes of 220 knees of patients with a mean age of 70 years (range: 42–90 years) who received the Triathlon^® prosthesis. Data were collected via postal questionnaire prior to surgery as well as at 8–12 weeks and at 1 year following surgery. Validated questionnaires were used including the WOMAC^® (Western Ontario and McMaster Universities) pain and function scales, the Knee injury and Osteoarthritis Outcome Score quality of life scale and the self-administered patient satisfaction scale.

RESULTS

This study found that patients who had the Triathlon^® prosthesis had significantly better pain relief (p<0.0001), function (p=0.028), knee related quality of life (p<0.0001) and satisfaction (p=0.0003) at three months after surgery than those who received the Kinemax Plus prosthesis. In addition, knee related quality of life (p=0.002) and satisfaction (p=0.021) were significantly higher at one year after surgery in Triathlon^® patients.

CONCLUSIONS

The findings suggest that return to function and reduction in pain may occur more quickly in patients with a Triathlon^® prosthesis than in those with the Kinemax Plus.     

Entamoeba histolytica induces human neutrophils to form NETs

Entamoeba histolytica invades the intestine and other organs during the pathogenesis of amoebiasis. In the early stages, the host organism responds with an inflammatory infiltrate composed mostly of neutrophils. It has been reported that these immune cells, activated by E. histolytica, exert a protective role by releasing proteolytic enzymes and generating reactive oxygen/nitrogen species (ROS/RNS) and antimicrobial peptides. It is now known that neutrophils also produce neutrophil extracellular traps (NETs), which are able to damage and kill pathogens. Studies have shown that intracellular protozoan pathogens, including Toxoplasma gondi, Plasmodium falciparum and Leishmania spp, induce neutrophils to release NETs and are damaged by them. However, the action of this mechanism has not been explored in relation to E. histolytica trophozoites. Through scanning electron, epifluorescence microscopy and viability assays, we show for first time that during in vitro interaction with E. histolytica trophozoites, human neutrophils released NETs that covered amoebas and reduced amoebic viability. These NETs presented histones, myeloperoxidase and decondensed chromatin. The results suggest that NETs participate in the elimination of the parasite.     

The salivary microbiota as a diagnostic indicator of oral cancer: A descriptive,non-randomized study of cancer-free and oral squamous cell carcinoma subjects

Background  

The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.