Encystation of Giardia lamblia leads to expression of antigens recognized by antibodies against conserved heat shock proteins.

During in vitro encystation, Giardia lamblia expresses several stage-specific proteins which are recognized in immunoblots by antisera raised against antigens from three different pathogens. The antigens belong to two different families of conserved stress proteins: (i) HSP60 purified from Legionella pneumophila and recombinant HSP60 from Mycobacterium bovis BCG and (ii) recombinant HSP70 from Plasmodium falciparum.     

Altered expression of hyaluronan synthase and hyaluronidase mRNA may affect hyaluronic acid distribution in keloid disease compared with normal skin

Keloid disease (KD) is a fibroproliferative disorder characterised partly by an altered extracellular matrix (ECM) profile. In fetal scarring, hyaluronic acid (HA) expression is increased, but is reduced in KD tissue compared with normal skin (NS). The expression of Hyaluronan Synthase (HAS) and hyaluronidase (HYAL) in KD and NS tissue were investigated for the first time using a range of techniques. Hyaluronan synthase and HYAL mRNA expression were significantly increased in NS tissue compared with KD tissue (P < 0.05). Immunohistological analysis of tissue indicated an accumulation of HAS and HYAL protein expression in KD compared with NS due to the thicker epidermis. No differences were observed in mRNA or protein expression in KD and NS fibroblasts. Reduced expression of HAS and HYAL may alter HA synthesis, degradation and accumulation in KD. Better understanding of the role of HA in KD may lead to novel therapeutic approaches to address the resulting ECM imbalance.     

Ventricular fibrillation during programmed ventricular stimulation: Incidence and clinical implications

Ventricular fibrillation occurred in 10 (3.3 percent) of 300 patients consecutively studied with programmed ventricular stimulation. One hundred twenty-five of these patients were studied with double ventricular extrastimuli including 68 patients with and 57 patients without documented or suspected ventricular tachycardia or fibrillation, or both. Ventricular fibrillation did not develop in response to a single ventricular extrastimulus delivered during sinus rhythm, ventricular pacing or ventricular tachycardia or in response to ventricular pacing at cycle lengths of 300 msec or greater and occurred only in response to double ventricular extrastimuli. All 10 patients who manifested ventricular fibrillation during programmed stimulation were in the group of patients with suspected or documented ventricular tachycardia or fibrillation. Ventricular fibrillation was initiated in seven patients with double ventricular extrastimuli delivered during sinus rhythm or ventricular pacing and in three patients with double ventricular extrastimuli delivered during ventricular tachycardia. Four patients had spontaneous conversion to sinus rhythm and the remainder underwent defibrillation without sequelae. Recurrent ventricular fibrillation occurred clinically in 7 of the 10 patients. This study suggests that ventricular fibrillation occurs uncommonly during programmed ventricular stimulation and only in response to double ventricular extrastimuli in patients in whom spontaneous episodes are likely to occur.     

Single‐stage application of a novel decellularized dermis for treatment‐resistant lower limb ulcers: Positive outcomes assessed by SIAscopy,laser perfusion,and 3D imaging,with sequential timed histological analysis

We present results of an original clinical study investigating efficacy of a decellularized dermal skin substitute (DCD) as part of a one‐stage therapeutic strategy for recalcitrant leg ulcers. Twenty patients with treatment‐resistant ulcers underwent hydrosurgical debridement, after which DCD was applied and covered with negative pressure dressings for 1 week. Participants were reviewed on seven occasions over 6 months. 3D photography, full‐field laser perfusion imaging, spectrophotometric intracutaneous analysis, and sequential biopsies were used to monitor healing. Mean ulcer duration and surface area prior to DCD placement were 4.76 years (range 0.25–40 years) and 13.11 cm² (range 1.06–40.75 cm²), respectively. Seventy percent of ulcers were venous. Surface area decreased in all patients after treatment (range 23–100%). Mean reduction was 87% after 6 months, and 60% of patients healed completely. Wound bed hemoglobin flux increased significantly 6 weeks after treatment (p = 0.005). Histological and immunohistochemical analysis confirmed progressive DCD integration with colonization by host fibroblasts, lymphocytes, and neutrophils, resulting in fibroplasia, reepithelialisation, and angiogenesis, with correlating raised CD31, collagen I, and collagen III levels. Subgroup analysis showed differing cellular behavior depending on wound duration, with delayed angiogenesis, reduced collagen deposition, and smaller reductions in surface area in ulcers present for over 1 year. The stain intensities of immunohistochemical markers including fibronectin, collagen, and CD31 differed depending on depth from the wound surface and presence of intact epithelium. DCD safely produced significant improvement in treatment‐resistant leg ulcers. With no requirement for hospital admission, anesthetic, or autogenic skin grafting, this treatment could be administered in hospital and community settings.     

Elderly patients are at increased risk for mortality undergoing surgical repair of dens fractures

Objective

Dens fractures are common cervical injuries in advanced aged patients. The presented study was undertaken to analyze the clinical results and risks of surgically treated patients with dens fractures over 70 years.

Methods

Data of 28 patients (17 female, 11 male) over 70 years treated from September 2004 to October 2009 were recorded. Clinical and radiological parameters were obtained including type of fracture, associated cervical and/or other injuries, comorbidities, symptoms, neurological condition, surgical strategy, postoperative course and complications.

Results

89% were in a good neurological condition before surgery (ASIA E or D). In most cases, surgery was performed at an early stage after trauma (21 patients within 5 days). Ventral screw fixation was the preferred surgical strategy (64%). A slight worsening of neurological functions immediately after operation was only seen in one patient. Five patients died in the early and 2 in the late postoperative course which means a treatment mortality of 25%. Among the surviving patients two had general medical complications.

Conclusion

Type II dens fractures are a common fracture of elderly patients. Our results are good concerning the neurological functions. Surgical and general medical complications were acceptable. However, the study also underlines that mortality rate is high and therefore treatment options should be well-considered in this high risk group.