The results of non-operative management of stiff joints in the hand.

We selected 500 patients randomly from a total of 1300 patients seen in our Hand Rehabilitation Center between 1971 and 1975; 212 of the 500 presented with a chief complaint of stiff hand joints. Of the 212 patients treated non-operatively, 173 responded sufficiently to this treatment alone. Of the 789 stiff joints, 686 responded sufficiently to this treatment alone. The results of this regime of non-operative treatment of stiff joints provide excellent functional improvement in most patients, with a large saving of money through the reduction in disability payments required.     

Heterochrony: Developmental mechanisms and evolutionary results

The concept of heterochrony, that the relative timing of ontogenetic events can shift during evolution, has been a major paradigm for understanding the role of developmental processes in evolution. In this paper we consider heterochrony from the perspective of developmental biology. Our objective is to redefine heterochrony more broadly so that the concept becomes readily applicable to the evolution of the full range of ontogenetic processes, from embryogenesis through the adult. Throughout, we stress the importance of considering heterochrony from a hierarchical perspective. Thus, we recognize that a heterochronic change at one level of organization may be the result of non-heterochronic events at an underlying level. As such, heterochrony must be studied using a combination of genetic, molecular, cellular, and morphological approaches.     

Mitotic cell populations obtained from a micro-carrier culturing system

Colcemid treatment of cell culture beads confluent with cells released a mitotic population of cells which was as efficient as that obtained by conventional shake-off procedures. The bead system provides an easy and efficient means for harvesting large quantities of mitotic cells, costs about one-tenth as much as conventional culturing techniques, and is at least 100 times more rapid.     

Aryl hydrocarbon hydroxylase activity in pulmonary alveolar macrophages and lymphocytes from lung cancer and noncancer patients: A correlation with family histories of cancer

Aryl hydrocarbon hydroxylase (AHH) activity was measured in pulmonary alveolar macrophages (PAMs) and peripheral blood lymphocytes from cigarette smokers with and without primary lung cancer. Frequency distribution analysis of AHH induction ratios for the two groups revealed an increased number of individuals in the lung cancer patient group with high lymphocyte induction values (P less than 0.05). A similar increase was not shown for high-PAM AHH values in lung cancer patients (P greater than 0.2). When individual PAM and lymphocyte AHH values were compared between noncancer and lung cancer patients, a positive correlation was observed for noncancer patients (r=0.195, P less than 0.001), but no correlation of these values was noted for lung cancer patients. The lung cancer patients were divided into three subgroups of patients showing (I) high PAM and low lymphocyte AHH levels, (II) low PAM and low lymphocyte AHH levels, and (III) low PAM and high lymphocyte AHH levels. When the incidence of family history of cancer was compared for these subgroups, no family cancer history was recorded for persons in subgroup II; however, individuals in subgroups I and III presented family cancer history incidence of 9.5% and 39.3%, respectively. Patients in group III averaged 6 years younger than those in group I. These data suggest that familial factors may be identified among lung cancer patients and that these factors appear to associate as either a cause of an effect with the capacity of pulmonary alveolar macrophages and lymphocytes to be induced for AHH. The data support the hypothesis that high AHH values may be characteristic of lung cancer patients but show that enzyme values determined from a single tissue, either PAMs or lymphocytes, may not be appropriate for showing whether high AHH inducibility is correlated with lung cancer.     

Functional homologies of acidic chromatin proteins in higher and lower eukaryotes

Within a specific fraction of acidic chromatin-associated proteins from HeLa and the lower eukaryote Physarum polycephalum numerous similarities exist. Several of the similar polypeptides in both cell types are synthesized and appear in the residual chromatin material while still others disappear in response to starvation, a common and universal stimulus. Proteins which incorporate no radioactive amino acids during starvation and ultimately disappear from the residual chromatin material are resynthesized upon refeeding. This resynthesis must be complete before mitosis will again occur. These observations suggest that within the complement of acidic chromatin proteins functional homologies exist in diverse eukaryotes.     

Experimental study of the optimal time for tenolysis

We have attempted to define the optimal time for tenolysis by evaluating the blood supply, the rupture rate, and the tensile strength of tenolysed and control tendons. In 128 chickens tenolysis was performed 1, 3, 6, 12, 16, and 24 weeks after primary tendon repair. Tenolysis at 1 and 3 weeks resulted in devascularization, weak tendons, and high rupture rates. Tenolysis at 6 weeks after the primary repair had mixed effects on the blood supply but weakened the tendon. Tenolysis at 12 weeks after the tendon repair did not weaken the tendon and resulted in an increased blood supply. Tenolysis at 16 and 24 weeks did not weaken the tendon, but had varied effects on the blood supply. We recommend an interval of 12 weeks between primary tendon repair and tenolysis.