Characterization of the Trr/Trx system in the fungal pathogen Candida glabrata

C. glabrata, an opportunistic fungal pathogen, can adapt and resist to different stress conditions. It is highly resistant to oxidant stress compared to other Candida spp and to the phylogenetically related but non-pathogen Saccharomyces cerevisiae. In this work, we describe the Trx/Trr system of C. glabrata composed of Trr1 and Trr2 (thioredoxin reductases) and Trx2 (thioredoxin) that are localized in the cytoplasm and Trx3 present in the mitochondrion. The transcriptional induction of TRR2 and TRX2 by oxidants depends on Yap1 and Skn7 and TRR1 and TRX3 have a low expression level. Both TRR2 and TRX2 play an important role in the oxidative stress response. The absence of TRX2 causes auxotrophy of methionine and cysteine. Trr1 and Trr2 are necessary for survival at high temperatures and for the chronological life span of C. glabrata. Furthermore, the Trx/Trr system is needed for survival in the presence of neutrophils. The role of TRR1 and TRX3 is not clear, but in the presence of neutrophils, they have non-overlapping functions with their TRR2 and TRX2 paralogues.

[Osteochondromas: introducing the subungual osteochondroma]

INTRODUCTION

Subungual osteochondromas are benign tumors of the sub- or periungual region, causing lifting, ulceration and deformity at that level.

OBJECTIVE

To research the incidence of subungual osteochondromas in a specific pediatric population.

MATERIAL AND METHODS

Retrospective, transversal, descriptive and observational study based on the review of records with a histopathological result of osteochondroma from 2001 to 2014.

RESULTS

The pathological assessment featured four osteochondromas that corresponded to the subungual presentation, with an equal gender distribution of 1:1, an average age of 9.5 years, right: left ratio of 3:1; the 4th finger was the most affected.

DISCUSSION

Subungual osteochondroma has an incidence of 8.5% of all osteochondromas.

[Comparative study of the management of congenital brachymetatarsia with elongation with callotaxis]

Brachymetatarsia is the > 5 mm shortening of the metatarsal parabolic arc of the foot, in one or more metatarsals. It is directly related with the early closure of the epiphyseal cartilage or with early fusion of the epiphyseal line of the distal end of the metatarsal. The fourth metatarsal is usually the most affected one. Females are more commonly affected, with a female to male ratio of 25:1; 72% of cases have bilateral involvement. The causes may be congenital, posttraumatic or result from specific conditions. A prospective, comparative study was conducted of patients with a diagnosis of congenital brachymetatarsia seen in 2007-2008 and 2008-2012. Seven patients were included in the former period: six girls and one boy. Eight patients were included in the latter period: five girls and three boys. The mean shortening achieved in the first group was 21.1 mm; in the second one, 18 mm, without regression. The daily distraction in both groups was 0.5 mm. Metatarsal elongation by means of callotaxis with external fixators is an appropriate procedure for adolescent patients about to achieve epiphyseal closure. The best results are obtained with gradual distraction at a rate of 0.5 mm per day.

[Infected pseudoarthrosis of the tibia, a pediatric case. Case report and literature review]

Chronic posttraumatic osteomyelitis and infected pseudoarthrosis of the tibia are complex problems associated with considerable morbidity which may compromise the viability of the involved limb. The most frequent age of presentation is 2 to 6 years, with predominance in males at a 2:1 ratio. We present the case of a male 4 year-old patient with diagnosis of infected pseudoarthrosis. During the physical exam a fistula was detected in the anterior aspect of the right leg, with discharge of purulent material, and inability for weight bearing and gait. X-rays, culture of the exudate and biopsy were performed. Treatment consisted of antimicrobial therapy, surgical debridement's, and application of an autologous bone graft. The infection was controlled, the tibia healed, and function was restored.

[Proximal focal femoral deficiency complicated by a proximal femur fracture]

Proximal focal femoral deficiency (PFFD) is a rare skeletal condition characterized by development failure of the subtrochanteric region of the femoral axis, with several degrees of shortening of the proximal region. There are no case reports of patients with this condition associated with a subtrochanteric fracture. We therefore describe herein the case of a newborn patient with clinical and radiographic diagnosis of proximal focal femoral deficiency complicated by a proximal femur fracture, and managed conservatively with pelvipodalic immobilization, which led to bone healing. The patient will continue to be managed in the long-term to assess and treat the sequelae of PFFD according to the growth stage he is in.

[Multicenter osteoblastic osteosarcoma in a preschooler. Case report]

Osteoblastic osteosarcoma is the most frequent malignant bone neoplasia in pediatric patients. It accounts for 50% of primary bone tumors and the most frequent age at presentation is adolescence, particularly during the growth spurts. Cases of children younger than 8 years of age have been reported in the literature. The purpose of this article is to report the case of a male, 19 month-old patient with osteoblastic osteosarcoma of the left distal femur and proximal tibia. It is considered as a special case due both to the age at presentation and to the multicenter feature of the tumor. This suggests that this entity may be more aggressive and rapidly growing in younger children. At the National Pediatrics Institute, in 35 years we only had three cases of children younger than 5 years.

[Elongation with callotaxis for congenital brachymetatarsia]

OBJECTIVE

To present 10 cases of congenital brachymetatarsia treated with elongation by means of callotaxis with external minifixators.

INTRODUCTION

Brachymetatarsia of one or more of the matatarsals involving one or both extremities is a congenital condition, more frequent in the right foot, with the 4th metatarsal most commonly affected.

MATERIAL AND METHODS

From May 2007 to September 2008, 7 patients with congenital brachymetatarsia, ages 8 to 15 years, were operated on. Two metatarsals were involved in 3 of them and thus the series included 10 procedures. All of them underwent lengthening through callotaxis with a monoaxial external mini-fixator.

RESULTS

Mean lengthening was 21.1 mm, with a range of 17 to 25 mm. The complications included two cases of lengthening regression of 5 mm each. Delayed healing was reported in one of these two cases, and healing occurred spontaneously at 6 months. Nine metatarsals healed without any problems; no infections or material intolerance occurred.

CONCLUSION

Lengthening of metatarsals through callotaxis with external mini-fixators is an appropriate procedure for pediatric and adolescent patients with congenital brachymetatarsia.

Effect of the quality of health care on permanent inability secondary to femoral fractures due to occupational accidents

OBJECTIVE

To construct and validate an indicator for evaluating the quality of care for femoral fractures, and to assess the contribution of the quality of health care as a determinant of partial permanent inability secondary to femoral fractures due to occupational accidents.

MATERIALS AND METHODS

The study was conducted from January to December 1995 at Mexican Institute of Social Security. The instrument was designed with experts' contribution along different stages and validated using implicit criteria and factorial analysis. A case-control study was then conducted to evaluate the contribution of the quality of care to inability secondary to femoral fractures. Cases were 108 active workers with permanent inability secondary to femoral fracture; controls were 94 active workers with fracture of femur but no permanent inability. Logistic regression modeling was used to establish the association between quality of care and partial permanent inability, adjusting by relevant variables.

RESULTS

The ultimate indicator of quality of care consisted of the following: Timely care, presurgical management, surgical management, and fracture complications. A final score over 229 points meant that the worker had received good quality of care. Workers getting 229 or less points had received poor quality of care. Forty-eight (44%) cases and 66 (70%) controls received good quality of medical care. The likelihood of partial permanent inability was almost three times higher among workers given poor quality of care (OR 2.95; 95% CI 1.5-5.5). According to the multivariate model, predictors of partial permanent inability were: Having exposed or epiphysiary fractures, being re-submitted to surgery, having less than 90 days of rehabilitation care, and receiving deficient medical care.

CONCLUSIONS

The constructed instrument was validated. The level of the quality of care received by workers is a determining factor for the generation of partial permanent inability. In workers having femoral fractures, it is important to consider timely medical care and early rehabilitation, to reduce the high incidence and prevalence of this medical problem in Mexico. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.