The diverse biological effects of the hormone somatostatin are mediated by five genetic different receptor subtypes (sst1-sst5), which belong to the superfamily of G-protein coupled receptors with seven transmembrane domains. The sst2 subtype is unique among the somatostatin receptors in its structure, since it is expressed in two protein variants which differ within their carboxy-terminal ends, generated by alternative splicing. Within the 5' untranslated region of the gene two introns separate three transcriptional units with distinct promoters. Due to the latter feature, the sst2 gene is also unique among all somatostatin receptor genes regarding its transcriptional regulation. The three alternative promoters are tissue specifically active and show alternative responsiveness to extracellular signals. The second sst2 promoter is important for expression of the gene in tissues where somatostatin has essential physiological functions, such as brain, pituitary and gastrointestinal tissues. Furthermore, it contains cis-acting regulatory elements involved in the transcriptional response to elevated cyclic AMP levels and glucocorticoids.

Animals↗

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[Solitary infantile myofibromatosis of the sacrum].

The infantile myofibromatosis is the most common fibrous tumor of infancy. One may find solitary lesions of dermal, visceral, musculoskeletal and subcutaneous tissues. Multiple lesions without visceral involvement generally take a benign course. Because the lesion is commonly known only to pathologists, infantile myofibromatosis is often misdiagnosed and underreported. Therefore we present a review of the pathology and symptoms of infantile myofibromatosis together with a case report of a solitary lesion of bone.

Adolescent↗

PubMedDate not supplied

Regulatory elements of the human proopiomelanocortin gene promoter.

Proopiomelanocortin (POMC) is expressed predominantly in the corticotrophic cells of the pituitary. Regulatory sequences required for the expression of the human (h) POMC gene were investigated using transient expression of hPOMC-CAT fusion genes in pituitary and nonpituitary cells in combination with DNase I footprint and gel retardation assays. Gene transfer experiments revealed that the hPOMC promoter is more efficiently transcribed in AtT-20 pituitary cells than in HeLa cells. Using deletion analysis, negative regulatory elements between nucleotides -676 and -414 and positive regulatory elements between nucleotides -414 and -93 could be identified. When placed in front of the heterologous thymidine kinase (tk) promoter, nucleotides -414/-223 enhance transcription in AtT-20 cells and in primary cultures of human pituitary tumor cells, but not in various nonpituitary cell lines. In contrast, a -112/-93 element enhances transcription of the tk promoter in all cells tested. DNase I footprint analysis revealed five sites protected by nuclear extracts obtained from AtT-20 cells within nucleotides -414 and -83 of the hPOMC promoter region. In contrast, only one of these sites (between nucleotides -115 and -83) was protected by nuclear extracts from HeLa cells. Gel mobility-shift experiments revealed that an oligonucleotide comprising nucleotides -112/-93 binds a novel nuclear protein. This protein may contribute to the non-cell type-specific expression of the hPOMC gene outside the pituitary, whereas at least five transcription factors seem to be required for high basal transcription of the gene in corticotrophic cells.

Base Sequence↗

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Anatomic location of spinal cord injury. Relationship to the cause of injury.

In a population based sample, 550 of 619 people with fatal and nonfatal spinal cord injuries were classified according to the cause of injury and according to the anatomic location of the highest spinal cord injury. Motor vehicle occupants accounted for 42% of the people with spinal cord injuries. Sixty percent of those injured had a cervical cord injury, 25% a thoracic cord injury, and 15% a lumbosacral cord injury. The specific anatomic locations most commonly injured were at C1 (12% of all spinal cord injuries), C6 (9%), and L2 (5%). The anatomic site of injury was significantly (P less than 0.001) related to the cause of injury. Thirty-seven percent of the spinal cord injuries from firearms and 97% of those from diving were located in the cervical cord. In contrast, 68% of spinal cord injuries to motor vehicle occupants were cervical; 17% at C1. The distribution of injuries among drivers was similar to that among other occupants.

Accidents, Traffic↗

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Prevalence of assault and perception of risk of assault in urban public service employment settings.

This study describes the prevalence and correlates of physical assaults, threats of assault, and workers' perceptions of safety in selected urban employment settings. Questionnaires were mailed to a random sample of 1,763 persons working at various jobs and sites throughout Los Angeles County. Workers were asked to describe their work environments, their perceptions of personal safety at work, and physical assaults and threats they had experienced. Three percent of the respondents reported being assaulted within the previous year and 14% reported being threatened within the previous 30 days. Younger workers, more educated workers, and those who worked with clients or patients were more likely to report assaults. Approximately one third of those who reported threats or assaults described the perpetrator(s) as clients, patients, or persons in legal custody, and one third described the perpetrator(s) as co-workers or supervisors. Fifty-two percent of the workers reported being concerned about their safety at work.

Adult↗

PubMedDate not supplied