Mantle cell lymphoma: primary oral presentation

Mantle-cell lymphoma is an uncommon lymphoid malignancy of B-cells. It is often aggressive and prognosis is poor. A 69-year-old gentleman with a history of ischaemic heart disease was referred from primary care with a painless right floor of mouth swelling that had been present for 1 month. He otherwise completely asymptomatic. Incisional biopsy of the lesion was undertaken and marker studies demonstrated mantle cell lymphoma. Positron emission tomography-computed tomography and bone marrow biopsy showed widespread but low volume involvement. The patient was referred to the haematology multidisciplinary team for further assessment and treatment.

Mcl1 regulates the terminal mitosis of neural precursor cells in the mammalian brain through p27Kip1

Cortical development requires the precise timing of neural precursor cell (NPC) terminal mitosis. Although cell cycle proteins regulate terminal mitosis, the factors that influence the cell cycle machinery are incompletely understood. Here we show in mice that myeloid cell leukemia 1 (Mcl1), an anti-apoptotic Bcl-2 protein required for the survival of NPCs, also regulates their terminal differentiation through the cell cycle regulator p27(Kip1). A BrdU-Ki67 cell profiling assay revealed that in utero electroporation of Mcl1 into NPCs in the embryonic neocortex increased NPC cell cycle exit (the leaving fraction). This was further supported by a decrease in proliferating NPCs (Pax6(+) radial glial cells and Tbr2(+) neural progenitors) and an increase in differentiating cells (Dcx(+) neuroblasts and Tbr1(+) neurons). Similarly, BrdU birth dating demonstrated that Mcl1 promotes premature NPC terminal mitosis giving rise to neurons of the deeper cortical layers, confirming their earlier birthdate. Changes in Mcl1 expression within NPCs caused concomitant changes in the levels of p27(Kip1) protein, a key regulator of NPC differentiation. Furthermore, in the absence of p27(Kip1), Mcl1 failed to induce NPC cell cycle exit, demonstrating that p27(Kip1) is required for Mcl1-mediated NPC terminal mitosis. In summary, we have identified a novel physiological role for anti-apoptotic Mcl1 in regulating NPC terminal differentiation.

Effectiveness of Oral Midazolam for Paediatric Dental Care: A retrospective study in two Specialist Centres

AIM

To analyse retrospectively the outcomes for children undergoing oral care under conscious sedation with oral midazolam and local analgesia at Leeds dental Institute, England and Westmead Dental Hospital, Sydney, Australia. Secondly, the study assessed the suitability of oral midazolam for paediatric dental treatment.

STUDY DESIGN

Retrospective study of clinical outcomes based on dental records.

METHODS

All children included in the study had been treated between September 2000 to August 2004 and full dental records were available. The dental records were examined using a standard pro forma sheet and data collected for: age, previous behaviour using the Frankl [1962] scale, units of work planned and achieved using the modified index of O'Sullivan and Curzon [1991], midazolam dosage and treatment outcome.

RESULTS

The study population consisted of 101 children aged 1-11 years in both Leeds (57 children) and Westmead (44 children). There were significant differences between Leeds and Westmead with respect to age (mean +/-SD) in years 5.0+/-1.0 versus 2.9+/-1.6; number of treatment visits 1.7 versus 1.1; sedation dose used 0.5-0.7 mg/kg versus 02.-0.3; type and amount of treatment planned 8.3 units versus 3.3 and achieved 7.5 versus 2.2, for both centres respectively. There was also a difference in overall success rates of rendering the children dentally fit of 65% v. 91%, respectively.

CONCLUSION

Oral midazolam was found to be a useful drug for the management of young children with behaviour problems. It was found, however, not to be effective in all cases and for the provision of all types of paediatric dentistry. The results indicate that, when using oral midazolam in children, the treatment should be restricted to simple restorations and extractions over a maximum of two visits.

Coaxial photorefractive methods: an optical analysis

We provide a novel geometrical optical analysis of two coaxial photorefractive methods (isotropic and orthogonal). The size of the photorefractive pattern is defined in terms of the critical optical parameters without reference to specific camera parameters. A set of equations is derived that defines the following: a working range where the photorefractive pattern increases linearly with refractive error and pupil size, a dead zone where changes in refractive error do not influence pattern size, and critical values where vignetting by the camera lens becomes important. From this analysis optical parameters can be systematically adjusted to vary a photorefractor's working range. Small discrepancies found between measurements taken with model eyes indicated threshold and blooming effects that require calibration.

Geometrical optical analysis of photorefractive methods

Photorefractive methods allow rapid measures of the refractive and accommodative state of infants and young children whose brief attention and co-operation limit the use of more traditional methods such as retinoscopy and autorefraction. Three methods have been defined: orthogonal, isotropic and eccentric. We provide a common geometrical optical analysis for these three methods where the photorefractive pattern is defined at the plane of focus of the camera. Since this plane is conjugate with the detector plane of the camera then the critical optical parameters can be defined without reference to the design of the camera by simply determining the relative magnification of the projected image of an object photographed at the camera's plane of focus. Specifically the pattern width CF (mm) over a photorefractor's working range can be defined for the isotropic and orthogonal methods as: [formula: see text] and for the eccentric method as: [formula: see text] where: K is a myopic refractive error of the eye (dioptres) (K Less than 0); P the distance of the flash source to the eye (dioptres); L the distance in front of the eye of the camera's plane of focus (dioptres) (L less than 0); GH the pupil diameter (mm); e the eccentricity of the flash source from the camera aperture (mm); M magnification of the image measured relative to the camera plane of focus.