Dental agenesis in Kallmann syndrome individuals with FGFR1 mutations

International Journal of Paediatric Dentistry 2010; 20: 305–312 Background. Kallmann syndrome (KS) is a rare genetic disorder characterised by central hypogonadism with a lack of sense of smell and in some cases renal aplasia, deafness, syndactyly, cleft lip/palate, and dental agenesis. To date, five genes for KS have been identified: KAL1, located on the X chromosome, and FGFR1, PROKR2, PROK2 and FGF8, which are involved in autosomally transmitted forms of KS. Aim. The study characterised the dental ageneses of individuals with KS associated with mutations in the FGFR1 gene. Design. Six individuals displaying dental agenesis were included. Clinical and radiological dental evaluations as well as medical anamneses were carried out. Results. Microdontia, screwdriver‐shaped mandibular incisors, thin molar roots, and patterns of dental agenesis in both dentitions were observed. One to nine teeth were missing, most frequently, in descending order, lateral mandibular incisors, second premolars of upper and lower jaws, and lateral maxillary incisors. The pattern of dental agenesis is associated with four new mutations in the FGFR1 gene. Conclusion: Dental agenesis may be a clinical feature of Kallmann syndrome caused by a mutation in the FGFR1 gene. These findings highlight the role that odontologists can play in the early diagnosis and treatment of gonadotropic deficiency.     

The effect of topical steroid application on natural killer cell activity

Peripheral blood natural killer (NK) cell activity of a group of 10 healthy non-atopic volunteers was reduced following the topical application of 15 g of 0.1 % betamethasone valerate ointment to the skin nightly for 1 week. In contrast, no such effect was observed when the inactive base of the steroid ointment was used. NK cell activity dropped significantly by day 7 ( P < 0.05) and then recovered, although NK cell activity at day 22 was still lower than that observed at the start of the experiment. These findings suggest that topically applied steroid is absorbed in sufficient amounts to cause a systemic effect on NK cell function. This may have implications in a number of dermatological disorders, including atopic dermatitis, where topical steroids form the mainstay of treatment.     

Natural-killer-cell activity in atopic dermatitis

Natural-killer (NK)-cell activity was measured in the peripheral blood of twenty patients with atopic dermatitis and in a group of thirteen age-matched non-atopic controls (nine subjects on thirteen occasions). The method uses a chromium-release assay with the human leukaemia cell line, K562, labelled with ^5lCr as the target cell. A highly significant reduction in NK-cell activity was found in the patients with atopic dermatitis.     

Natural killer cell activity in atopic dermatitis: a sequential study

It is well-recognized that patients with atopic dermatitis handle certain cutaneous viral infections poorly. As natural killer (NK) cell activity is considered to contribute to the immune response to viral infection, seven young adults with atopic dermatitis had their NK cell function assessed over a 12-month period. Natural killer cell activity was found to correlate inversely with disease activity. The more active the disease, the greater was the reduction in NK cell function (P<0.01). In addition, a strong correlation between clinical activity and IgE was shown (P<0.001).     

Chloride channels in myotonia congenita assessed by velocity recovery cycles

Introduction: Myotonia congenita (MC) is caused by congenital defects in the muscle chloride channel CLC‐1. This study used muscle velocity recovery cycles (MVRCs) to investigate how membrane function is affected. Methods: MVRCs and responses to repetitive stimulation were compared between 18 patients with genetically confirmed MC (13 recessive, 7 dominant) and 30 age‐matched, normal controls. Results: MC patients exhibited increased early supernormality, but this was prevented by treatment with sodium channel blockers. After multiple conditioning stimuli, late supernormality was enhanced in all MC patients, indicating delayed repolarization. These abnormalities were similar between the MC subtypes, but recessive patients showed a greater drop in amplitude during repetitive stimulation. Conclusions: MVRCs indicate that chloride conductance only becomes important when muscle fibers are depolarized. The differential responses to repetitive stimulation suggest that, in dominant MC, the affected chloride channels are activated by strong depolarization, consistent with a positive shift of the CLC‐1 activation curve. Muscle Nerve 49 : 845–857, 2014     

CHANGES IN CEREBRAL HEMODYNAMICS IN PRETERM INFANTS WITH AND WITHOUT PATENT DUCTUS ARTERIOSUS

ABSTRACT. We compared anterior cerebral pulsatility index (ACPI), anterior cerebral mean flow velocity (ACMFV), common carotid pulsatility index (CPI) and common carotid mean flow velocity (CMFV) in three groups of preterm infants with birth-weights less than 1500 grams: 6 without evidence of PDA (group A), 6 with PDA treated with fluid restriction, diuretics or digoxin (group B) and 6 with surgical ligation of PDA (group C). Infants were assessed in three time periods: the first four days of life, five days before surgical ligation and five days post-ligation. Analyses of variance showed no significant differences in the three groups for the four measures in time 1. In time 2, ACPI was 0.61 for group A, 0.58 for group B, 0.78 for group C ( p <0.01). ACMFV was 9.22 for group A, 7.71 for group B, 6.37 for group C ( p <0.05). CPI was 0.84 for group A, 0.83 for group B, 0.90 for group C (NS); CMFV was 7.80 for group A, 5.63 for group B, 4.28 for group C ( p <0.01). In time 3, significant differences ( p <0.01) were found only for CMFV.