Leukemia inhibitory factor upregulates cytokine expression by a murine stromal cell line enabling the maintenance of highly enriched competitive repopulating stem cells

Attempts to maintain or expand primitive hematopoietic stem cells in vitro without the concomitant loss of their differentiative and proliferative potential in vivo have largely been unsuccessful. To investigate this problem, we compared the ability of three cloned bone marrow (BM) stromal cell lines to support the growth of primitive Thy- 1lo Sca-1+H-2Khi cells isolated by fluorescence-activated cell sorting from the BM of Ly-5.2 mice treated 1 day previously with 5-fluo- rouracil. Sorted cells were highly enriched in cobblestone area-forming cells (CAFC), but their frequency was dependent on the stromal cell lines used in this assay (1 per 45 cells on SyS-1; 1 per 97 cells on PA6). In the presence of recombinant leukemia inhibitory factor (LIF), CAFC cloning efficiency was increased to 1 per 8 cells on SyS-1 and 1 per 11 cells on PA6, thus showing the high clonogenicity of this primitive stem cell population. More primitive stem cells with competitive repopulating potential were measured by injecting the sorted cells into lethally irradiated Ly-5.1 mice together with 10(5) radioprotective Ly-5.1 BM cells whose long-term repopulating ability has been "compromised" by two previous cycles of marrow transplantation and regeneration. Donor-derived lymphocytes and granulocytes were detected in 66% of animals injected with 50 sorted cells. To quantitate the maintenance of competitive repopulating units (CRU) by stromal cells, sorted cells were transplanted at limiting dilution before and after being cultured for 2 weeks on adherent layers of SyS-1, PA6, or S17 cells. CRU represented 1 per 55 freshly sorted cells. CRU could be recovered from cocultures supported by all three stromal cell lines, but their numbers were approximately-sevenfold less than on day 0. In contrast, the addition of LIF to stromal cultures improved CRU survival by 2.5-fold on S17 and PA6 cells (approximately two-fold to threefold decline), and enabled their maintenance on SyS-1. LIF appeared to act indirectly, because alone it did not support the proliferation of Thy- 1lo Sca-1+H-2Khi cells in stroma-free cultures. Polymerase chain reaction (RT-PCR) analysis revealed that Interleukin-1beta (IL-1 beta) IL-2, IL-6, granulocyte-colony stimulating factor, granulocyte macrophage-colony stimulating factor, transforming growth factors, LIF, and Steel Factor (SLF) mRNAs were upregulated in SyS-1 within 1 to 6 hours of LIF-stimulation. To determine if increased expression of SLF by LIF-stimulated SyS-1 cells could account for their capacity to support stem cells, sorted calls were cocultured on simian CV-E cells that were transfected with an expression vector encoding membrane-bound SLF, or supplemented with soluble SLF. In both cases, SLF synergized with IL-6 produced endogenously by CV-E cells enabling CAFC growth equivalent to that on LIF-stimulated SyS-1. CAFC development on LIF- stimulated SyS-1 could also be completely abrogated by an anti-SLF antibody. These data provide evidence for a role of LIF in the support of long-term repopulating stem cells by indirectly promoting cytokine expression by BM stroma. Furthermore, we have used quantitative assays to show a maintenance of CRU numbers, with retention of in vivo function following ex vivo culture.     

Post-cimetidine Surveillance for up to Ten Years: Incidence of Carcinoma of the Stomach and Oesophagus

The long-term effects of cimetidine on the occurrence of gastricand oesophageal cancer were assessed in a prospective cohortstudy of 9928 patients who had been prescribed cimetidine. Theywere first identified between 1978 and 1980, and cancer registrationsand deaths were identified among them over a period of up to10 years. One hundred and eleven cancers were identified afterthe start of cimetidine treatment: 71 were adenocarcinomas ofthe stomach, 27 were carcinomas of the cardia and/or oesophagus(22 adenocarcinomas, five unknown histology) and the remaining13 tumours were squamous cell cancers of the oesophagus. Onlysix patients presented with early gastric cancers. Over a periodof eight years the ratio of observed to expected (O/E) gastriccancer deaths has fallen from 10.7 (p<0.001) to 1.2 (NS).The O/E ratio of oesophageal cancer deaths also fell over thefirst six years of study, from 5.4 (p<0.01) to 1.4 (NS) butit has risen slightly in years 7 and 8 to 3.7 (p<0.05). Thesefindings do not suggest that there is an increased risk of developingoesophageal or gastric cancer from cimetidine treatment, andare generally consistent with cimetidine being used inadvertentlyto treat the early symptoms of gastric and oesophageal cancer.The slight rise in oesophageal cancer deaths in years 7 and8 was unexpected and will be the subject of further observation.     

Premature thelarche in Kabuki make-up syndrome

A 2 year old girl who has Kabuki make-up syndrome with isolated premature thelarche is presented. She has unique ocular abnormalities which have not been reported previously. In the literature at least 85 patients, most of them from Japan, have been reported. This is the first reported non-Japanese Asian case.     

The geographical assignment of cancer units: patient accessibility as an optimal allocation problem

The seminal report A Policy Framework for Commissioning Cancer Services provides the foundation for a major reorganisation of cancer service provision in England and Wales. One central recommendation of the report, the establishment of a tier of specialised cancer units in each Health Authority Region has raised the fundamental question of where those units are to be located. In particular, a declared objective of the report is for services to be planned to maximise their accessibility to patients. This paper demonstrates a classical method (location-allocation modelling) by which the accessibility criterion can be used to determine the optimal number, location and capacity of units for a given cancer site. The method is illustrated with reference to cervical cancer in Trent Health Authority Region. The implications of the method for the guidance of access-related decisions on the placement of cancer services are considered, and the wider relevance of the method to the organisation of service provision in other branches of medicine is suggested.     

Idiopathic torsion dystonia: assignment of a gene to chromosome 18p in a German family with adult onset, autosomal dominant inheritance and purely focal distribution

Idiopathic torsion dystonia (ITD) is a group of movement disorders which is usually inherited in an autosomal dominant manner with reduced penetrance. Most patients with ITD present with focal dystonia at adult age. However, thus far, this common subform remained unmapped chromosomally. In contrast, a rare early onset, more generalized form of ITD has been mapped to chromosome 9q34. Our linkage study in a large pedigree with seven definitely affected, six possibly affected and 16 phenotypically unaffected family members assigns an ITD gene for the common focal form with a maximal lod score of 3.17 to the region telomeric of D18S1153 on chromosome 18p.      

Role of ultrasound therapy in the healing of tibial stress fractures

Background: Stress fracture is the single most common cause for the lost number of manpower days during training. The conventional treatment options begin with rest and cessation of precipitating activity. However the demands of military training provide little tolerance for prolonged periods of rest. In the recent past ultrasound therapy (UST) has been reported to speed up healing of stress fractures.