Nutritional management of chronic renal disease.

The importance of nutritional evaluation and diet therapy in the overall management of the patient with chronic renal disease is unquestioned. Its application often is limited by a lack of knowledge regarding the requirement for certain nutrients in health as well as the way in which these requirements are modified by chronic disease. However, the most important and often the most difficult task is engaging the cooperation of the patient in the nutritional management of his disease. Acceptance of dietary manipulation depends upon the patient's family structure and the importance of food and mealtime within the particular cultural and ethnic background. Dietary recommendations implemented by the parents of pediatric patients may produce untoward changes in the child's behavior, attitudes toward food, or relationships with other family members. Dietary recommendations must be carefully planned and their effect reevaluated. They should be individualized to the age, intellectural skills, and developmental stage of the patient.     

Haematological prognostic indices after myocardial infarction: evidence from the diet and reinfarction trial (DART).

Data from the Diet and Reinfarction Trial were examined to check the prognostic effects of plasma fibrinogen, plasma viscosity, white blood cell count, haemoglobin and mean platelet volume in 92 deaths among 1755 men who had recently recovered from acute myocardial infarction. All these variables were significantly associated with all-cause mortality over the following 18 months (haemoglobin negatively, the others positively). Those who gave up smoking following their infarct had a lower mortality than those who continued to smoke (4.1% and 7.9% respectively), and this effect appeared to be mediated by fibrinogen levels. Smoking habit accounted for only part of the prognostic effect of fibrinogen and white blood cell count. Haematological variables have an important prognostic significance after myocardial infarction. Cessation of smoking after myocardial infarction is worthwhile and has a favourable effect on plasma fibrinogen.     

Longevity mutants do not establish any “new science” of ageing

The biological reasons for ageing are now well known, so it is no longer an unsolved problem in biology. Furthermore, there is only one science of ageing, which is continually advancing. The significance and importance of the mutations that lengthen the lifespan of invertebrates can be assessed only in relationship to previous well-established studies of ageing. The mutant strains of model organisms that increase longevity have altered nutrient signalling pathways similar to the effects of dietary restriction, and so it is likely that there is a shift in the trade-off between reproduction and maintenance of the soma. To believe that the isolation and characterisation of a few invertebrate mutations (as well as those in yeast) will “galvanise” the field and provide new insights into human ageing is an extreme point of view which does not recognize the huge progress in ageing research that has been made in the last 50 years or so.     

A novel SRY missense mutation affecting nuclear import in a 46,XY female patient with bilateral gonadoblastoma

Patients with disorders of sex development (DSD), especially those with gonadal dysgenesis and hypovirilization, are at risk of developing the so-called type II germ cell tumors (GCTs). Both carcinoma in situ and gonadoblastoma (GB) can be the precursor lesion, resulting in a seminomatous or non-seminomatous invasive cancer. SRY mutations residing in the HMG domain are found in 10–15% of 46,XY gonadal dysgenesis cases. This domain contains two nuclear localization signals (NLSs). In this study, we report a unique case of a phenotypical normal woman, diagnosed as a patient with 46,XY gonadal dysgenesis, with an NLS missense mutation, on the basis of the histological diagnosis of a unilateral GB. The normal role of SRY in gonadal development is the upregulation of SOX9 expression. The premalignant lesion of the initially removed gonad was positive for OCT3/4, TSPY and stem cell factor in germ cells, and for FOXL2 in the stromal component (ie, granulosa cells), but not for SOX9. On the basis of these findings, prophylactical gonadectomy of the other gonad was performed, also showing a GB lesion positive for both FOXL2 (ovary) and SOX9 (testis). The identified W70L mutation in the SRY gene resulted in a 50% reduction in the nuclear accumulation of the mutant protein compared with wild type. This likely explains the diminished SOX9 expression, and therefore the lack of proper Sertoli cell differentiation during development. This case shows the value of the proper diagnosis of human GCTs in identification of patients with DSD, which allows subsequent early diagnosis and prevention of the development of an invasive cancer, likely to be treated by chemotherapy at young age.     

Reduction of cerebrospinal fluid rhinorrhea after vestibular schwannoma surgery by reconstruction of the drilled porus acusticus with hydroxyapatite bone cement

OBJECT: Cerebrospinal fluid (CSF) rhinorrhea remains a significant cause of morbidity after resection of vestibular schwannomas (VSs), with rates of rhinorrhea after this procedure reported to range between 0 and 27%. The authors investigated whether reconstruction of the drilled posterior wall of the porus acusticus with hydroxyapatite cement (HAC) would decrease the incidence of postoperative CSF rhinorrhea. METHODS: A prospective observational study of 130 consecutive patients who underwent surgery for reconstruction of the posterior wall of the drilled porus acusticus with HAC was conducted between October 2002 and September 2005. All patients underwent a retrosigmoid transmeatal approach for VS resection and were followed up to document cases of CSF rhinorrhea, incisional CSF leak, meningitis, or rhinorrhea-associated meningitis. A cohort of 150 patients with VSs who were treated with the same surgical approach but without HAC reconstruction served as a control group. RESULTS: The authors found that HAC reconstruction of the porus acusticus wall significantly reduced the rate of postoperative CSF rhinorrhea in their patients. In the patients treated with HAC, rhinorrhea developed in only three patients (2.3%) compared with 18 patients (12%) in the control group. This was a statistically significant finding (p = 0.002, odds ratio = 5.8). CONCLUSIONS: The use of HAC in the reconstruction of the drilled posterior wall of the porus acusticus, occluding exposed air cells, greatly reduces the risk of CSF rhinorrhea.     

Towards resorbable 3D-printed scaffolds for craniofacial bone regeneration

This review will briefly examine the development of 3D-printed scaffolds for craniofacial bone regeneration. We will, in particular, highlight our work using Poly(L-lactic acid) (PLLA) and collagen-based bio-inks. This paper is a narrative review of the materials used for scaffold fabrication by 3D printing. We have also reviewed two types of scaffolds that we designed and fabricated. Poly(L-lactic acid) (PLLA) scaffolds were printed using fused deposition modelling technology. Collagen-based scaffolds were printed using a bioprinting technique. These scaffolds were tested for their physical properties and biocompatibility. Work in the emerging field of 3D-printed scaffolds for bone repair is briefly reviewed. Our work provides an example of PLLA scaffolds that were successfully 3D-printed with optimal porosity, pore size and fibre thickness. The compressive modulus was similar to, or better than, the trabecular bone of the mandible. PLLA scaffolds generated an electric potential upon cyclic/repeated loading. The crystallinity was reduced during the 3D printing. The hydrolytic degradation was relatively slow. Osteoblast-like cells did not attach to uncoated scaffolds but attached well and proliferated after coating the scaffold with fibrinogen. Collagen-based bio-ink scaffolds were also printed successfully. Osteoclast-like cells adhered, differentiated, and survived well on the scaffold. Efforts are underway to identify means to improve the structural stability of the collagen-based scaffolds, perhaps through mineralization by the polymer-induced liquid precursor process. 3D-printing technology is promising for constructing next-generation bone regeneration scaffolds. We describe our efforts to test PLLA and collagen scaffolds produced by 3D printing. The 3D-printed PLLA scaffolds showed promising properties akin to natural bone. Collagen scaffolds need further work to improve structural integrity. Ideally, such biological scaffolds will be mineralized to produce true bone biomimetics. These scaffolds warrant further investigation for bone regeneration.     

Life after death: A child's reaction to the death of a parent

The death of a parent is a traumatic event for a child. This paper will correlate children's ideas about death with various developmental stages. In addition, it will provide suggestions from experts about how adults can help children go through the painful grieving process. Mental health professionals who work with children will find practical suggestions on helping children cope with the experience of losing a parent to death.