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Prolonging dying is the same as prolonging living--one more response to Long.

In earlier publications, we had argued that Paul Ramsey is inconsistent because he simultaneously asserts that (i) 'all our days and years are of equal worth' and (ii) 'that it is permissible to refrain from prolonging the lives of some dying patients'. Thomas Long has suggested that we have not shown that Paul Ramsey is inconsistent. Ramsey and we, he holds, start from incommensurable metaphysical views: for Ramsey, the dying process has religious significance--God is calling his servant home. While it is normally a good thing to keep a patient alive, it would, for Ramsey, show deafness to God's call to keep a dying patient alive. It is true we do not share Paul Ramsey's religious views. It is, however, not necessary to rely on any particular metaphysical views to refute Ramsey's position. For Ramsey's view to be internally consistent, Ramsey would have to be able to distinguish between dying and non-dying patients. We examine some of Ramsey's examples and show that his practical judgements do not allow us to draw this distinction. This means that, contra Long, we hold fast to our charge that Ramsey's view is inconsistent.

Adult↗

Philosophical inquiry in nursing: an argument for radical empiricism as a philosophical framework for the phenomenology of addiction.

Philosophical inquiry involves examination of the meaning of a phenomenon within the larger framework of the human condition and a particular view of reality. Argumentation is the method. In this study, the author argues that the metaphysics of radical empiricism enhances the understanding of the immediate subjective experience or phenomenology of addiction. When applied to subjective narratives of the addiction experience from literature, this metaphysics confers meaning to the changes in consciousness that occur in the immediate subjective experience of addiction. Conclusions revealed from the application of this perspective highlight novel feelings, the will and changing sense of self, and the human values of belonging and freedom. This study also revealed the value of the philosophical method of inquiry: to temporize our moral judgments and enrich our perspective of the human values within the addiction phenomenon. These values support and clarify the belief system of nursing.

Consciousness↗

Clinical and statistical prediction: a retrospective and would-be integrative perspective.

One of the early participants in the clinical-statistical controversy describes his effort to mediate the dispute and to direct attention to the underlying issues, to most of which the box scores were irrelevant. A previously undiscussed undercurrent of the controversy is the conflict between different metaphysical world views, the history of which for the past few hundred years is quickly sketched. The mechanist metaphysics of behaviorism, which has long been dominant in American mainstream psychology, favors objective and statistical approaches and discourages interest in judgement, an issue that nevertheless refuses to go away. Systems philosophy is proposed as an integrative alternative.

Behaviorism↗

Phenotypic expressions of a Gly 154Arg mutation in type II collagen in two unrelated patients with spondyloepimetaphyseal dysplasia (SEMD).

Type II collagenopathies consist of chondrodysplasias ranging from lethal to mild in severity. A large number of mutations has been found in the COL2A1 gene. Glycine substitutions have been the most common types of mutation. Genotype-phenotype correlations in type II collagenopathies have not been established, partly because of insufficient clinical and radiographic description of the patients. We found a glycine-to-arginine substitution at position 154 in type II collagen in two unrelated isolated propositi with spondyloepimetaphyseal dysplasia and provide a comparative clinical and radiographic analysis from birth to young adulthood for this condition. The clinical phenotype was disproportionate short stature with varus/valgus deformities of the lower limbs requiring corrective osteotomies, and lumbar lordosis. The skeletal radiographs showed an evolution from short tubular bones, delayed epiphyseal development, and mild vertebral involvement to severe metaphyseal dysplasia with dappling irregularities, and hip "dysplasia." The metaphyseal abnormalities disappeared by adulthood.

Adult↗

SPONASTRIME dysplasia: report on a female patient with severe skeletal changes.

We report on a 6-year-old girl with SPONASTRIME dysplasia, characterized by short-limbed dwarfism, a relatively large head, midfacial hypoplasia, a saddle nose, moderate deformities of the vertebral bodies, striated metaphyses, and normal intelligence. She showed severe skeletal changes including marked delay of epiphyseal ossification, evident metaphyseal dysplasia, and osteopathia striata more pronounced than in most of the previously reported patients with this disorder. The patient we describe and a male patient reported by Camera et al. [1994: Pediatr Radiol 24:322-324] are likely to represent the severely-affected end of the clinical spectrum of the disorder. These finding thus rule out the X-linked mode of inheritance of the disorder proposed by Camera et al. [1994: Pediatr Radiol 24: 322-324]. Alternatively, the two severely-affected patients may represent a variant form of the disorder. There is evidence that SPONASTRIME dysplasia is a genetically heterogeneous disorder.

Bone Diseases, Developmental↗

A rare form of spondylometaphyseal dysplasia-type A4.

We present 2 cases of a previously apparently unreported spondylo-metaphyseal dysplasia comprising dwarfism, severe metaphyseal changes, ovoid vertebrae and mild platyspondyly with anterior tonguing of the vertebral bodies. The inheritance may be autosomal recessive.

Child, Preschool↗

Comparison of bone loss during normal lactation with estrogen deficiency osteopenia and immobilization osteopenia in the rat.

BACKGROUND: Substantial changes in mineral and skeletal metabolism occur during pregnancy and lactation. The purpose of this study was to compare three contrasting osteopenic states in the rat: (1) physiological (lactation), (2) endocrine-deficiency (ovariectomy), and (3) lack of mechanical usage (immobilization). METHODS: One group of female rats went through a pregnancy and 21 days of lactation (LAC). Another group was ovariectomized (OVX) for 6 weeks, and another group had one hind limb immobilized (IMM) for 6 weeks. Bone mineral density was determined by photon absorptiometry, and changes in cancellous and cortical bone were determined by backscattered electron imaging (BSE), scanning electron microscopy (SEM), structural morphometry, and fluorochrome-based histomorphometry. RESULTS: The LAC group gained the most weight but had the least bone mineral density and metaphyseal bone mass. The OVX and IMM groups also had less bone mass than controls (CONT). Changes in cancellous bone structure occurred in all groups, but the IMM group had a more uniform distribution of metaphyseal bone loss. Longitudinal bone growth was greater in the IMM and OVX groups but less in the LAC group. Cancellous bone formation rates were greater in the OVX and LAC group. Cortical bone width was less in the LAC, IMM, and OVX groups. Periosteal bone formation was greater in the OVX group but less in the LAC group. CONCLUSIONS: Considerable osteopenic changes occur in cancellous and cortical bone during the first reproductive cycle in the rat. The osteopenia of lactation is somewhat similar to that observed after ovariectomy, likely because both are hypoestrogenic conditions. Because this bone loss occurs during a normal physiological event, these data suggest that before the first reproductive cycle, the female rat has a skeletal mass in excess of that needed for normal mechanical usage.

Absorptiometry, Photon↗

Invasion of joints by primary bone sarcomas in adults.

In a retrospective macroscopic and microscopic study of celloidin-embedded macrosections from 45 adults with primary metaphyseal intraosseous sarcomas, we ascertained the incidence, extend, and mode of tumor extension into, across, or around articular cartilage into a joint. Invasion of articular cartilage by tumor occurred in more than one-third of the macrosections examined. In more than one-half of the cases, the sarcoma extended under the capsule insertion to involve the margin of the articular cartilage, thus leaving only a pseudocapsule between tumor and joint. Tumors frequently extended across or around the osseous-tendinous junction of the cruciate ligaments into the knee joint. Our findings have important implications for the surgical management of appendicular metaphyseal intraosseous sarcomas. For primary bone sarcomas, extraarticular resections should be considered seriously when limb salvage is contemplated, especially in the knee region.

Adolescent↗

An ovine model to evaluate the biologic properties of impacted morselized bone graft substitutes.

The objectives of this study were to develop and evaluate a bone-defect model to study the biologic behavior of biomaterials being considered for impaction grafting in revision hip arthroplasty. A miniature impactor was designed to produce pellets of aggregates at a standard compactive effort. In Phase 1, 22 sheep underwent implantation of pellets into six metaphyseal defects in both rear limbs. In Phase 2, eight sheep underwent surgical implantation of four pellets in metaphyseal defects. Defects were sealed with polymethylmethacrylate in both phases. Healing of the defects was evaluated at 7 weeks (Phase 1, n = 11) and 14 weeks (n =19) with computed tomography, histology, and histomorphometry. Complications in Phase 1 included four femoral fractures and migration of cement seals (18/102 defects). No complications occurred in Phase 2. Whereas no difference was found between left and right limbs, osteogenesis and incorporation of biomaterials varied among implantation sites. For comparison of grafting materials, treatment site allocations were randomized according to a Latin square design. This model allows evaluation of several impacted aggregates (including large particles) in the same animal. It is particularly suitable for analyzing the biologic properties of grafting materials prior to evaluation under loading conditions.

Animals↗

Fibrochondrogenesis: radiologic and histologic studies.

Fibrochondrogenesis is a distinct, neonatally lethal, short-limb skeletal dysplasia which was first described in a single patient in 1978. We report the radiographic and morphologic studies of 2 additional unrelated stillborn infants with fibrochondrogenesis. This syndrome has distinct radiographic and chondro-osseous morphologic defects different from those seen in the other known skeletal dysplasias. The long bones are short and dumbbell-shaped with metaphyseal flare. The spine is platyspondylic with superior-inferior clefting defects, and the ribs are short and distally cupped. The growth-plate cartilage is grossly disorganized and has a densely fibrous collagenous matrix when examined by light and electron microscopy. Light, transmission, and scanning electron microscopy shows diaphyseal and metaphyseal trabecular bone to be normal.

Abnormalities, Multiple↗

Three conditions in neonatal asphyxiating thoracic dysplasia (Jeune) and short rib-polydactyly syndrome spectrum: a clinicopathologic study.

Clinicopathologic examination of eight patients with asphyxiating thoracic dysplasia (Jeune; ATD) disclosed two different types, which were designated as type 1 and type 2. Type 1 ATD was characterized by the presence of radiologically irregular metaphyseal ends and histopathologically irregular cartilage bone junction with patchy distribution of physeal zone of hypertrophy. Type 2 ATD showed radiologically smooth metaphyseal ends and histopathologically diffusely retarded and disorganized physes with smooth cartilage bone junctions. Examination of four patients with the "Verma-Naumoff" short rib-polydactyly syndrome showed many radiologic and pathologic features similar to those of type 1 ATD. Differential diagnosis of these three osteochondrodysplasias is discussed along with chondroectodermal dysplasia (Ellis-van Creveld), short rib-polydactyly syndrome type 1 (Saldino-Noonan), short rib-polydactyly syndrome type 2 (Majewski), and the new short rib syndrome reported by Beemer et al [1983].

Asphyxia Neonatorum↗

Radiological findings in Hallermann-Streiff syndrome: report of five cases and a review of the literature.

Hallermann-Streiff syndrome (HSS) is a rare disorder with an associated constellation of radiological findings that may aid in the diagnosis of affected individuals. We reviewed the skeletal surveys of 5 affected individuals and noted some characteristic and constant findings. Radiological findings can include a large, poorly ossified skull with decreased ossification in the sutural areas. There was an increase in the number of Wormian bones. Severe mid-facial hypoplasia was present along with a prominent nasal bone. The skull films also showed an abnormally obtuse or nearly straight gonial angle. The teeth appeared small. The long bones were thin and gracile in appearance and often showed poor demarcation of the cortex from the medullary portion. Abnormal bowing of the radius and ulna was seen neonatally in 2 cases. There was widening at the metaphyseal ends of the long bones. The ribs were thin, but normal in length. The vertebral bodies were noted to be small and 3 cases had platyspondyly. There was a decreased number of sternal ossification enters. The metacarpals were also thin and gracile in appearance with metaphyseal widening. We conclude that these characteristic radiological findings in the newborn with HSS can aid in the diagnosis, and a skeletal survey in suspected individuals may be valuable in confirming the diagnosis.

Adolescent↗

Weissenbacher-Zweymüller syndrome: a distinct autosomal recessive skeletal dysplasia.

The Weissenbacher-Zweymüller syndrome (WZS) is defined as congenital neonatal rhizomelic dwarfism with metaphyseal widening of the long bones and vertebral coronal clefts. Catch-up growth after 2-3 years is one of the striking manifestations. It is generally thought that WZS is a neonatal expression of the Stickler syndrome, even though in the latter, myopia, retinal detachment and a progressive metaphyseal dysplasia are characteristics that are not found in WZS. A critical analysis of all published patients with WZS in addition to 5 patients in 3 new families, shows that the WZS is a distinct syndrome of delayed skeletal maturation, different from the Stickler syndrome, and inherited as an autosomal recessive trait. The recognition of its unique characteristics has important implications in genetic counseling.

Bone Diseases, Developmental↗

Osteogenesis imperfecta: the distinction from child abuse and the recognition of a variant form.

Unexplained fractures are characteristic of both osteogenesis imperfecta (OI) and non-accidental injury (NAI) but in most cases the diagnosis is straightforward. However, in a few OI patients an initial diagnosis of NAI is made. Factors contributing to such difficulties include failure to recognise that OI can occur without a family history, without blue sclerae, without osteopenia, without an excess of Wormian bones, or with metaphyseal fractures. In addition we report on 39 patients with an unusual history in that fractures only occurred in the first year of life. Rib fractures, metaphyseal abnormalities and periosteal reactions were common. The initial diagnosis was usually OI if the fractures occurred in hospital, but NAI if they appeared to have been sustained at home. Additional findings such as anaemia, vomiting, hepatomegaly, and apnoeic attacks were often found in these patients. The disorder has some similarities to the syndrome of infantile copper deficiency. Like the latter it is particularly common in preterm infants and in twins. Therefore, we are attempting to examine the incidence of significant hypocupraemia in unselected preterm infants. We suggest that the likely cause of this "temporary brittle bone disease" is a temporary deficiency of an enzyme, perhaps a metalloenzyme, involved in the post-translational processing of collagen.

Child Abuse↗

Agenesis of the corpus callosum with mental retardation and osseous lesions.

We report on a patient with agenesis of corpus callosum, mental retardation, and unusual hitherto undescribed bone changes. The latter include multiple Wormian bones, thin ribs, short, straight, laterally tapering clavicles, small iliac bodies, high iliac angles, triangular areas of sclerosis in the iliac bones, minimal metaphyseal irregularity, striated trabecular pattern in some metaphyses, granular ossification pattern of the patellae, hypoplastic distal phalanges, minimal flatness of phalangeal epiphyses, and retarded bone age. This patient represents a new mental retardation syndrome with agenesis of corpus callosum and unusual bone changes.

Abnormalities, Multiple↗

Spondyloepimetaphyseal dysplasia with joint laxity (SEMDJL): clinical and radiological findings in a Guatemalan patient.

We report on a patient of Guatemalan descent whose physical and radiological findings are consistent with a diagnosis of spondyloepimetaphyseal dysplasia with joint laxity (SEMDJL). This is a rare, autosomal recessive skeletal dysplasia with short limbs, severe scoliosis, high dorsal kyphoscoliosis, and joint hypermobility. Most described patients with SEMDJL are from the Afrikaans-speaking communities of South Africa. Patients with SEMDJL have an oval face, prominent eyes, and blue sclerae. Our patient's height and weight were below the fifth centile. She had prominent eyes with blue sclerae, a narrow, high-arched palate, pectus carinatum, severe scoliosis, and hyperextensibility and instability of most joints, with limited extension and supination of her elbows. A review of her roentgenograms showed severe scoliosis, poorly developed ischial, iliac, and pubic bones, a "bat-like" appearance of the iliac bones, "dysplastic" acetabulum, minimal metaphyseal and epiphyseal abnormalities at the knees, deformation of the proximal femoral metaphyses, and generalized brachydactyly of the hands and feet. This disorder may be more common than previously thought, and the diagnosis should be considered in any child with a dwarfing condition and joint laxity.

Child, Preschool↗

A disorder resembling pseudoachondroplasia but without COMP mutation.

Pseudoachondroplasia (PA) is an autosomal dominant skeletal dysplasia characterized by disproportionate short stature, generalized ligamentous laxity, irregular epi-metaphyseal ossification, and vertebral anomalies that regress with age. It usually manifests in the second year of life or later. The clinically and radiographically variable disorder is caused by mutations in the COMP gene. Parental gonadal mosaicism may lead to recurrence of the disorder in children of unaffected parents. Here, we describe sibs with bone changes similar to those seen in very severe PA born to clinically and radiographically unaffected parents. Sequencing of all 19 exons of the COMP gene failed to disclose a mutation. The sibs appear to be affected by a disorder resembling PA but resulting from a defect of an extracellular matrix protein other than COMP. It may be suspected in patients with unusually severe dwarfism, severe epi-metaphyseal abnormalities, and persistent platyspondyly.

Achondroplasia↗

Dominant negative mutations in the C-propeptide of COL2A1 cause platyspondylic lethal skeletal dysplasia, torrance type, and define a novel subfamily within the type 2 collagenopathies.

Platyspondylic lethal skeletal dysplasia (PLSD) Torrance type (PLSD-T) is a rare skeletal dysplasia characterized by platyspondyly, brachydactyly, and metaphyseal changes. Generally a perinatally lethal disease, a few long-term survivors have been reported. Recently, mutations in the carboxy-propeptide of type II collagen have been identified in two patients with PLSD-T, indicating that PLSD-T is a type 2 collagen-associated disorder. We studied eight additional cases of PLSD-T and found that all had mutations in the C-propeptide domain of COL2A1. The mutational spectrum includes missense, stop codon and frameshift mutations. All non-sense mutations were located in the last exon, where they would escape non-sense-mediated RNA-decay. We conclude that PLSD-T is caused by mutations in the C-propeptide domain of COL2A1, which lead to biosynthesis of an altered collagen chain (as opposed to a null allele). Similar mutations have recently been found to be the cause of spondyloperipheral dysplasia, a non-lethal dominant disorder whose clinical and radiographical features overlap those of the rare long-term survivors with PLSD-T. Thus, spondyloperipheral dysplasia and PLSD-T constitute a novel subfamily within the type II collagenopathies, associated with specific mutations in the C-propeptide domain and characterized by distinctive radiological features including metaphyseal changes and brachydactyly that set them apart from other type 2 collagenopathies associated with mutations in the triple-helical domain of COL2A1. The specific phenotype of C-propeptide mutations could result from a combination of diminished collagen fibril formation, toxic effects through the accumulation of unfolded collagen chains inside the chondrocytes, and alteration of a putative signaling function of the carboxy-propeptide of type 2 collagen.

Child, Preschool↗