Internal calvarial bone distraction in rabbits with delayed-onset coronal suture synostosis

Recent studies have identified a subpopulation of craniosynostotic individuals who exhibit progressive or delayed-onset synostosis and mild craniofacial growth abnormalities. These individuals may be good candidates for nonextirpation, distraction osteogenesis therapy. The present study was designed to test this hypothesis by using internal calvarial bone distraction in a rabbit model with familial delayed-onset craniosynostosis. Data were collected from 159 rabbits: 71 normal controls, 72 with delayed-onset coronal suture synostosis, 8 with delayed-onset coronal suture synostosis and coronal suturectomy, and 8 with delayed-onset coronal suture synostosis and distraction. At 10 days of age, all rabbits had amalgam markers placed on both sides of the frontonasal, coronal, and anterior lambdoidal sutures. At 25 days of age, correction was accomplished through either a 5-mm-wide suturectomy or distraction osteogenesis. An internal distraction appliance was fixed to the frontal and parietal bones and percutaneously and intermittently activated at an average of 0.10 mm/day for 42 days (4.11 mm total). Serial radiographs were taken at 10, 25, 42, and 84 days of age. Results revealed that rabbits with delayed-onset synostosis had significantly (p < 0.01) reduced coronal suture growth rates (0.04 mm/day) compared with the other three groups (0.07 mm/day). Rabbits with suturectomy and rabbits with distraction showed similar coronal suture responses. However, from 42 to 84 days of age, rabbits with distraction showed reduced growth at the vault sutures and abnormal growth patterns in cranial vault width, cranial vault shape, and cranial base angulation compared with the other three groups. Results demonstrated that, although the normal coronal suture growth rate was maintained in rabbits with delayed-onset synostosis using intermittent distraction osteogenesis, normal adult craniofacial structure was not achieved. Such anomalous growth was probably a result of altered growth vectors and compressive forces at adjacent sutures during distraction. These findings suggest that distraction osteogenesis without corticotomy may be a treatment alternative in individuals with progressive, delayed-onset synostosis, but that internal appliances that generate low-level, continuous distractive forces should be investigated and developed.     

2-(4-Aminophenyl)benzothiazoles: novel agents with selective profiles of in vitro anti-tumour activity

OBJECTIVE: To evaluate the results of cervical cytology screening in the National Breast and Cervical Cancer Early Detection Program and to compare the findings with results from other screening programs. METHODS: We analyzed data on 312,858 women aged 18 years and older who received one or more Papanicolaou smears, and follow-up if indicated, from October 1991 through June 1995 at screening sites across the United States providing comprehensive National Breast and Cervical Cancer Early Detection Program services. RESULTS: Of the women screened, more than half were 40 years or older; slightly less than half (44%) were of racial and ethnic minorities. During the first screening cycle, 3.8% of Papanicolaou tests were reported as abnormal (squamous intraepithelial lesion [SIL] or squamous cell cancer); proportions of abnormals decreased with increasing age. The age-adjusted rate of biopsy-confirmed cervical intraepithelial neoplasia (CIN) II or worse among women screened was 7.4 per 1000 Papanicolaou tests; rates of CIN were highest among young women, but cancer rates peaked among women in their 50s and 60s. The percentages of first screening cycle-Papanicolaou tests interpreted as high-grade SIL and squamous cell carcinoma associated with biopsy-confirmed CIN II or worse (the positive predictive value) were 56.0% for CIN II/III and 3.7% for invasive cancer. Of the 150 invasive cancers diagnosed, 54.0% were classified as local disease. CONCLUSION: Observed results emphasize the duality of cervical neoplasia-CIN in younger women and invasive cancer in older women. This finding points to the importance of reaching both younger and older women for cervical cancer screening.     

Stuttering therapy in the elementary school setting: guidelines for clinician-teacher collaboration

This article describes guidelines for developing an effective collaborative/consultative approach to the treatment of stuttering in an elementary school setting. Four primary areas of shared clinician/teacher responsibility are discussed, which include: education, observation, facilitation of fluent speech, and generalization of speech fluency. Although the speech-language pathologist should initiate the teacher's involvement in a child's therapy, both the clinician and teacher should work toward developing a mutually influential partnership, through which the specific needs of individual children who stutter can be addressed in a comprehensive manner.     

Information content of individual genetic sequences

Related genetic sequences having a common function can be described by Shannon's information measure and depicted graphically by a sequence logo. Though useful for many purposes, sequence logos only show the average sequence conservation, and inferring the conservation for individual sequences is difficult. This limitation is overcome by the individual information ( R i) technique described here. The method begins by generating a weight matrix from the frequencies of each nucleotide or amino acid at each position of the aligned sequences. This matrix is then applied to the sequences themselves to determine the sequence conservation of each individual sequence. The matrix is unique because the average of these assignments is the total sequence conservation, ad there is only one way to construct such a matrix. For binding sites on polynucleotides, the weight matrix has a natural cut off that distinguishes functional sequences from other sequences. R i values are on an absolute scale measured in bits of information so the conservation of different biological functions can be compared with one another. The matrix can be used to rank-order the sequences, to search for new sequences, to compare sequences to other quantitative data such as binding energy or distance between binding sites, to distinguish mutations from polymorphisms, to design sequences of a given strength, and to detect errors in databases. The R i method has been used to identify previously undescribed but experimentally verified DNA binding sites. The individual information distribution was determined for E. coli ribosome binding sites, bacterial Fis binding sites, and human donor and acceptor splice junctions, among others. The distributions demonstrate clearly that the consensus sequence is highly unusual, and hence is a poor method to describe naturally occurring binding sites.     

The effect of chenotherapy on the reservoir function of the gallbladder in cholelithiasis patients]

The effect of chenodeoxycholic acid (CDCA) on the reservoir function of the gallbladder was studied in 46 patients with cholesterol cholelithiasis. There was a dependence between a clear increase of filling of the gallbladder in patients treated by this method with subsequent sharp reduction of its size and development of dyspepsia and diarrhea. In 14 patients increase of the gallbladder against the background of chemotherapy was not authentic but no dyspeptic phenomena occurred. Thus, decompensation of the reservoir function of the gallbladder in patients with cholelithiasis against the background of chemotherapy are manifested by a significant increase of the gallbladder size with subsequent emptying of bile into the duodenum and development of collagenous diarrhea.