Identification of an oncogenic form of the thrombopoietin receptor MPL using retrovirus-mediated gene transfer

Thrombopoietin and its receptor (MPL) are important regulators of megakaryopoiesis. We have identified an activating mutation of MPL using a combination of a retrovirus-mediated gene transfer and polymerase chain reaction-driven random mutagenesis. This point mutation causes a single amino acid substitution from Ser498 to Asn498 in the transmembrane region and abrogates factor-dependency of all interleukin-3-dependent cell lines tested. Murine interleukin-3- dependent Ba/F3 cells expressing the mutated but not the normal form of MPL were tumorigenic when transduced into syngeneic mice. Analysis of intracellular signaling pathways indicated that the mutant MPL protein constitutively activated two distinct signaling pathways, SHC-Raf-MAPK and JAK2-STAT3/STAT5.     

A survey of the polycystic ovary syndrome in the Greek island of Lesbos: hormonal and metabolic profile

Polycystic ovary syndrome (PCOS) is characterized by hyperandrogenism, chronic anovulation, and oligomenorrhea (O/M). PCOS has variable clinical phenotypes, biochemical features, and metabolic abnormalities. To determine the prevalence of PCOS in the Greek population as well as the metabolic parameters, we performed a cross-sectional study of 192 women of reproductive age (17-45 yr), living on the Greek island of Lesbos. They were divided into 4 groups according to the presence of hirsutism (defined as a Ferriman-Gallwey score > or = 6) and O/M: group N (n = 108), regular menses and absence of hirsutism; group 1 (n = 56), regular menses and hirsutism; group 2 (n = 10), O/M and absence of hirsutism; and group 3 (n = 18), O/M and hirsutism. Body mass index, waist to hip ratio, and mean blood pressure did not differ among the studied groups. Hormonal profile was assessed by measuring free testosterone (FT). The prevalence of PCOS, defined by the presence of O/M and biochemical hyperandrogenism (FT > or = 95th percentile of the normal women), was estimated to be 6.77% (13 women of 192). Higher FT levels were observed in group 3 (O/M and hirsutism) compared with groups N (P < 0.00001) and 1 (P < 0.0001) and in groups 1 (hirsutism) and 2 (O/M) compared with group N (P < 0.0001 and P < 0.005, respectively). Sex hormone-binding globulin levels were lower in women with PCOS and in groups 1 and 3 than those in group N (P < 0.002, P < 0.02, and P < 0.002, respectively) independently of the body mass index. The metabolic profile was investigated by measurements of fasting glucose (FG), fasting insulin (FI), and estimation of the fasting glucose to insulin ratio (FG:I ratio). After covariance adjusted for the BMI, FI levels were higher in group 3 and in women with PCOS than in the normal (P < 0.005 and P < 0.002, respectively) and the hirsute (P < 0.05 and P < 0.02, respectively) women, whereas FG levels did not differ among the studied groups. The FG:I ratio was lower in group 3, group 1, and in women with PCOS than in normal women (P < 0.05). Finally, a high incidence of family history of diabetes mellitus (P = 0.001) and menstrual disorders (P = 0.01) was observed in women with PCOS, in contrast to the normal and hirsute women. In conclusion, PCOS appears to be a particularly common endocrine disorder in the Greek population under study (prevalence, 6.77%); furthermore, it is associated with certain metabolic abnormalities. These data also suggest that the severity of the fasting hyperinsulinemia is associated with the severity of the clinical phenotype of hyperandrogenism independently of obesity.     

A novel temporal‐predominant neuro‐astroglial tauopathy associated with TMEM106B gene polymorphism in FTLD/ALS‐TDP

Polymorphisms in TMEM106B, a gene on chromosome 7p21.3 involved in lysosomal trafficking, correlates to worse neuropathological, and clinical outcomes in frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS) with TDP‐43 inclusions. In a small cohort of C9orf72 expansion carriers, we previously found an atypical, neuroglial tauopathy in cases harboring a TMEM106B rs1990622 A/A genotype. To test whether TMEM106B genotype affects the risk of developing atypical tauopathy under a recessive genotype model (presence versus absence of two major alleles: A/A vs. A/G and G/G). We characterized the atypical tauopathy neuropathologically and determined its frequency by TMEM106B rs1990622 genotypes in 90 postmortem cases with a primary diagnosis of FTLD/ALS‐TDP [mean age at death 65.5 years (±8.1), 40% female]. We investigated the effect of this new atypical tauopathy on demographics and clinical and neuropsychological metrics. We also genotyped TMEM106B in an independent series with phenotypically similar cases. Sixteen cases (16/90, 17.7 %) showed the temporal‐predominant neuro‐astroglial tauopathy, and 93.7% of them carried an A/A genotype (vs. ~35% in a population cohort). The odds ratio of FTLD/ALS‐TDP individuals with the A/A genotype showing neuro‐astroglial tauopathy was 13.9. Individuals with this tauopathy were older at onset (p = 0.01). The validation cohort had a similarly high proportion of rs1990622 A/A genotype. TDP‐43 and tau changes co‐occur in a subset of neurons. Our data add to the growing body of evidence that TMEM106B polymorphisms may modulate neurodegeneration. A distinctive medial temporal predominant, 4‐repeat, neuro‐astroglial tauopathy strongly correlates to TMEM106B A/A genotype in FTLD/ALS‐TDP cases.     

Management of bisphosphonate‐related osteonecrosis of the jaw: a literature review

Osteonecrosis of the jaw (ONJ) is a serious side effect of bisphosphonate use in patients with osteoporosis, Paget's disease, hypercalcemia of malignancy, metastatic bone disease and multiple myeloma, although recently this complication has also been reported in patients under non‐bisphosphonate medication, such as denosumab and bevacizumab. The occurrence of ONJ is higher in oncology patients treated with high‐dose iv bisphosphonates than in osteoporosis patients treated with oral bisphosphonates. Although multiple hypotheses have been proposed, the exact pathogenic mechanism of ONJ still remains unclear. As treatment protocols based on randomized controlled trials (RCTs) do not exist, we critically reviewed the existing data concerning the management of bisphosphonate‐related osteonecrosis of the jaw, including the most recent data for the use of teriparatide and hyperbaric oxygen.     

Long-term protection of hematopoiesis against the cytotoxic effects of multiple doses of nitrosourea by retrovirus-mediated expression of human O6-alkylguanine-DNA-alkyltransferase

A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas.     

A difficult diagnosis of Hodgkin lymphoma due to immune thrombocytopenia

We report a rare clinical presentation of childhood Hodgkin lymphoma with immune thrombocytopenia. Diagnostic biopsy of the abdominal mass was performed after administration of intravenous immunoglobulins, steroids, and platelet transfusion. Concomitant thrombocytopenia complicated the whole diagnosis work up and the initial management of neoplasia.     

The management of trauma victims with head injury: a study by the national confidential enquiry into patient outcome and death

Introduction

In 2006 the National Confidential Enquiry into Patient Outcome and Death undertook a large prospective study of trauma care, which revealed several findings pertaining to the management of head injuries in a sample of 493 patients.

Methods

Case note data were collected for all trauma patients admitted to all hospitals accepting emergencies in England, Wales, Northern Ireland and the Channel Islands over a three-month period. Severely injured patients with an injury severity score (ISS) of ≥16 were included in the study. The case notes for these patients were peer reviewed by a multidisciplinary group of clinicians, who rated the overall level of care the patient received.

Results

Of the 795 patients who met the inclusion criteria for the study, 493 were admitted with a head injury. Room for improvement in the level of care was found in a substantial number of patients (265/493). Good practice was found to be highest in high volume centres. The overall head injury management was found to be satisfactory in 84% of cases (319/381).

Conclusions

This study has shown that care for trauma patients with head injury is frequently rated as less than good and suggests potential long-term remedies for the problem, including a reconfiguration of trauma services and better provision of neurocritical care facilities.     

Globular glial tauopathies (GGT): consensus recommendations

Recent studies have highlighted a group of 4-repeat (4R) tauopathies that are characterised neuropathologically by widespread, globular glial inclusions (GGIs). Tau immunohistochemistry reveals 4R immunoreactive globular oligodendroglial and astrocytic inclusions and the latter are predominantly negative for Gallyas silver staining. These cases are associated with a range of clinical presentations, which correlate with the severity and distribution of underlying tau pathology and neurodegeneration. Their heterogeneous clinicopathological features combined with their rarity and under-recognition have led to cases characterised by GGIs being described in the literature using various and redundant terminologies. In this report, a group of neuropathologists form a consensus on the terminology and classification of cases with GGIs. After studying microscopic images from previously reported cases with suspected GGIs (n = 22), this panel of neuropathologists with extensive experience in the diagnosis of neurodegenerative diseases and a documented record of previous experience with at least one case with GGIs, agreed that (1) GGIs were present in all the cases reviewed; (2) the morphology of globular astrocytic inclusions was different to tufted astrocytes and finally that (3) the cases represented a number of different neuropathological subtypes. They also agreed that the different morphological subtypes are likely to be part of a spectrum of a distinct disease entity, for which they recommend that the overarching term globular glial tauopathy (GGT) should be used. Type I cases typically present with frontotemporal dementia, which correlates with the fronto-temporal distribution of pathology. Type II cases are characterised by pyramidal features reflecting motor cortex involvement and corticospinal tract degeneration. Type III cases can present with a combination of frontotemporal dementia and motor neuron disease with fronto-temporal cortex, motor cortex and corticospinal tract being severely affected. Extrapyramidal features can be present in Type II and III cases and significant degeneration of the white matter is a feature of all GGT subtypes. Improved detection and classification will be necessary for the establishment of neuropathological and clinical diagnostic research criteria in the future.