Autosomal recessive blepharoptosis,cleft lip/palate,dental anomalies,and ectrodactyly

Fluorescence in situ hybridization (FISH) with α-satellite DNA probes was used to study whole-arm chromosome translocation products in a family in which the propositus was shown to have a monosomy 18p/trisomy 20p imbalance. By this approach, we show that the chromosome 18 α-satellite DNA block is split into 2 smaller units, whereas the chromosome 20 breakpoint is not included within the α-satellite DNA region. We found no evidence to suggest that this split α-satellite DNA region has reduced or impaired the function of the centromere or that it contributed to the phenotype of the propositus. The FISH technique critically demonstrated the involvement of a whole-arm translocation in this case and provided accurate identification of breakpoints, which was not possible with standard banding techniques. © Wiley-Liss, Inc.     

SCHWANN CELLS AND THE REGROWTH OF AXONS IN THE MAMMALIAN CNS: A REVIEW OF TRANSPLANTATION STUDIES IN THE RAT VISUAL SYSTEM

1. We have used peripheral nerve transplants or cultured Schwann cells grafted in association with different types of polymer to study axonal regrowth in the rat visual system. In some instances the glia were co-grafted with fetal tectal tissue. 2. The studies have two main aims: (i) to determine whether retinal axons can be induced to regrow at a site distant from their cell soma, that is, after damage to the brachial region of the optic tract; (ii) to determine whether retinal axons exposed to Schwann cells retain the ability to recognize their appropriate target neurons in CNS tissue. 3. In brachial lesion studies, Schwann cells were placed in the lesion site in association with nitrocellulose papers, within polycarbonate tubes in the presence or absence of a supporting extracellular matrix (ECM), or within polymer hydrogel scaffolds. Autologous sciatic nerve grafts were also used. Immuno-histochemical studies revealed the presence of regenerating axons within all polymer bridges. Regrowth of retinal axons was also seen, however, growth was not extensive and was limited to the proximal 1–1.5 mm of the implants. 4. In target innervation experiments, two surgical paradigms were developed. In one experiment, a segment of sciatic nerve was autografted onto the transected optic nerve in adult rats and the distal end of each graft was placed adjacent to fetal tectal (target) tissue implanted into the frontal cortex. To date, we have not been able to demonstrate selective recognition of target regions within tectal transplants by retinal axons exiting the sciatic nerve implants. 5. In the second experiment, Schwann cells were mixed with fetal tectal cells and co-grafted to the midbrain of newborn host rats. Schwann cells altered the characteristic pattern of host retinal growth into tectal grafts; in some cases axons were induced to grow away from appropriate target areas by nearby co-grafted Schwann cells. 6. In summary, Schwann cell/polymer scaffolds may provide a useful way of promoting the regrowth of damaged axons in the CNS, however: (i) in adults, at least, their effectiveness is reduced if they are located at a distance from the cell bodies giving rise to regenerating axons; (ii) in some circumstances exposure to a peripheral glial environment may affect the capacity of regenerating axons to recognize appropriate target cells in the CNS neuropil.     

Eighteen-month Coronal Caries Incidence in North Carolina Older Adults

In this longitudinal study of a random sample of North Carolinians over the age of 65 and living in their homes, 325 blacks and 280 whites were examined and interviewed 18 months after baseline examinations. Coronal caries incidence was greater among whites than blacks. The increment due to teeth becoming root fragments were similar for both races; however, there were more newly crowned teeth among whites. Newly crowned surfaces were not used as part of the caries increment in logistic regression models to investigate potential risk predictors. For blacks, caries development over the 18-month period was associated with a higher lactobacillus score and more coronal caries at baseline, more previously filled coronal surfaces, and lack of active membership in clubs or other groups. For whites, having no self-reported tooth sensitivity, having a lower socioeconomic index score, taking antihistamine medications at baseline, and having the perception of more problems after the age of 40 than before were all associated with the development of coronal caries.     

Life-threatening respiratory failure due to cranial dystonia after dental procedure in a patient with multiple system atrophy.

We report on a woman with a an 8-year history of multiple system atrophy with predominance of parkinsonism who developed jaw-locking oromandibular dystonia within hours after insertion of ill-fitting dentures. Dystonia spread rapidly to involve other facial muscles and the larynx causing stridor with respiratory failure necessitating crush intubation.     

Application of an immunosensor for the detection of the β-lactam antibiotic, cephalexin

Public concern surrounding antibiotic contamination in food and food products has made it imperative to develop analytical methods for their detection. Polyclonal antibodies were used in the development of a surface plasmon resonance (SPR)-based inhibition immunoassay for cephalexin. A conjugate consisting of cephalexin-bovine serum albumin (BSA) was immobilized on the dextran gel surface of the sensor chip. Binding/regeneration studies of antibody to immobilized cephalexin were studied and dissociation of the antibody from the immobilized cephalexin was easily achieved with 10 mmol l^-1 NaOH. Forty surface regeneration cycles were carried out and found to be reproducible with only a 7.4% decrease in binding over this number of regenerations. Model inhibition immunoassays for cephalexin were developed in PBS and spiked milk samples with detection ranges of 4.88 to 2,500 ng ml^-1 and 244 to 3,906 pg ml^-1, respectively.     

Dislocation of an upper third molar into the maxillary sinus after a severe trauma: a case report

Abstract – Dental injuries are common following facial trauma. This article presents a rare injury: the dislocation of a third molar into the maxillary sinus after complex mandibular and maxillary tuberosity fractures. The possible mechanism and clinical treatment are discussed.     

Traumatic dental injuries and associated factors among Brazilian preschool children

Abstract –  The main objective of this study was to assess the epidemiology of traumatic dental injuries (TDI) to the primary teeth of preschool children and second, to investigate whether TDI were related to anterior open bite and, third, whether TDI are related to socio-economic circumstances in an urban Brazilian population. A clinical examination was performed during the National Day of Children's Vaccination. TDI were classified according to the modified classification proposed by Ellis. In addition to those criteria the presence of tooth discoloration was recorded. An interview was carried out with mothers or guardians. The data collected included mother's level of education and living conditions. The prevalence of TDI was 9.4%. The maxillary central incisors were the most affected teeth. Most children with a TDI experienced traumatic injuries to one tooth (6.3%), while 2.8% had two and 0.4% had three traumatized teeth. The most common crown fracture was in enamel only (68.8%), followed by crown fracture of enamel and dentin (13.8%). Missing teeth following trauma occurred in 10.9% of those with TDI. The prevalence of tooth discoloration was 5.1%. Children with anterior open bite had twice the level the level of TDI compared to those with normal occlusions ( P  = 0.001). Socio-economic factors were not statistically significantly associated with the occurrence of TDI. The prevalence of dental injuries in Brazilian preschool children was low. Children with anterior open bite experienced more dental injuries. Neither of the indicators of socio-economic status was related to the prevalence of TDI.     

Predicting the experience of dentinal caries or restorative dental treatment in adolescents using D1 and D3 visual caries assessments

Standardised epidemiological caries assessments used in oral health surveys have been shown to be poor at predicting whether a tooth surface will be treated restoratively when a patient visits a dentist. However, it has been argued that oral health surveys may be more relevant in determining needs at the level of an individual or groups of individuals. The objective of this study was to determine the discriminatory power of visual caries assessments at two thresholds (D₁ & D₃) in adolescents of average age 12.1 years to predict experience of dentinal caries 3 years later or the experience of restorative treatment (not re‐treatment) during the 3‐year period. The data was derived from a prospective 3‐year longitudinal study in which the dental care provided by 41 dentists for 403 adolescents was monitored. Dental caries experience was monitored by annual standardised assessments of caries undertaken by a single trained examiner. ROC analysis showed that caries assessed visually at the D₁ threshold in 12‐year‐olds was a better predictor (P < 0.001) of experiencing some dentinal caries after 3 years (Az = 0.781) than was caries assessed visually at D₃ threshold in 12‐year‐olds (Az = 0.670). Assessing caries visually at either the D₁ or the D₃ threshold had no discriminatory power for predicting whether an individual would experience some restorative treatment during the ensuing 3‐year period (Az for D₁ = 0.507; Az for D₃ = 0.518).     

替牙(牙合)时期前牙反(牙合)矫治中弓丝弯制的探讨

目的　探讨在“2× 4”矫治技术中弓丝弯制的方法及原理。方法　替牙牙合时期前牙反牙合患者 2 4例 ,使用粗弓丝 ,在其弓丝上弯制各种曲形 ,并根据不同错牙合类型 ,处理各种曲与牙齿、带环关系 ,防止出现磨牙旋转移动等异常。结果　 2～ 6个月纠正反牙合 ,2 4例替牙牙合时期反牙合患者得以早期矫治。结论　本方法矫治时间短 ,效果明显 ,操作简单 ,能够达到较为理想的矫治效果