Extracellular matrix synthesis is required for the movement of sclerotome and neural crest cells on collagen

During early embryogenesis cells of several different populations disperse by active cell movement from one location to another. Preexisting extracellular materials are major determinants of these dispersal patterns, but the cells are also able to modify their substrata by synthesizing and secreting extracellular matrix molecules as they move. In order to determine the contribution made by these deposited materials, several tissues from the early chick embryo have been cultured in the presence of inhibitors of extracellular matrix synthesis and secretion. The tissues examined were sclerotome cells from differentiated somites and neural crest cells. For comparison, undifferentiated somites were also cultured. The movement of these cells was compared in type I collagen gel culture and in conventional culture on artificial substrata. Inhibitors of collagen synthesis were used (cis-hydroxy proline and L-azetidine-2-carboxylic acid) in addition to a proteoglycan inhibitor (p-nitrophenyl-xylopyranoside) and a secretion inhibitor (monensin). Results indicate that sclerotome cells require collagen synthesis for movement in a collagen matrix. Reversal of the effects of collagen inhibitors, by proline and type II collagen, suggest that sclerotome cells normally condition the type I matrix in order to move in it. Inhibition of proteoglycan synthesis produced the greatest effect on the movement of neural crest cells regardless of the substratum, confirming an important role for these molecules in the crest migratory routes. The attachment of all cells to collagen was highly sensitive to the presence of monensin, which is known to reduce the deposition of glycosaminoglycans and fibronectin. These results suggest that conditioning of the extracellular matrix by newly synthesized material is required for cell attachment and movement during early development.

Age-dependent effects of sodium butyrate and hydrocortisone on acetylation of high mobility group proteins of rat liver

The in vitro acetylation of high mobility group (HMG) proteins and its modulation by sodium butyrate and hydrocortisone have been studied using liver slices of young (13-) and old (114-week-old) rats. Acetylation of total HMG proteins was significantly higher in young than old rats. HMG 1, in particular, showed greater acetylation than others. Whereas acetylation of HMG 1 and 2 decreased drastically, that of HMG 14 and 17 increased in old age. In young rats, sodium butyrate and hydrocortisone stimulated acetylation of HMG 14 and 17, and decreased that of HMG 2. Butyrate had no effect on HMG 1, but hydrocortisone decreased it. In old rats, butyrate and hydrocortisone decreased acetylation of all HMGs, except HMG 17, which was stimulated to a slight extent by butyrate.

Duplication of the pinna (polyotia) in a case of Brachmann-de Lange syndrome

A rare case of polyotia in Brachmann-de Lange syndrome (Goodman and Gorlin, 1977) is presented and a method for the surgical correction of the duplicated auricle briefly outlined. A review of relevant literature is included in the discussion.

High density lipoprotein2. Relationship of the plasma levels of this lipoprotein species to its composition, to the magnitude of postprandial lipemia, and to the activities of lipoprotein lipase and hepatic lipase

Lipoprotein lipase (LPL) activity in postheparin plasma of 38 normolipidemic volunteers was related to the magnitude of postprandial lipemia after a fat meal, to triglyceride content of high density lipoprotein2 (HDL2), to hepatic lipase (HL) activity, and to HDL2 levels. LPL activity correlated indirectly with lipemia, triglyceride content of HDL2, HL activity, and levels of HDL2 but not of HDL3. HL activity correlated directly with lipemia and indirectly with HDL2 levels. Triglyceride content of HDL2 correlated directly with lipemia and indirectly with HDL2 levels. In HDL2, abundance of apolipoprotein (apo) A-II and the apoA-I/apoA-II ratio varied widely. The latter correlated positively with LPL activity and HDL2 levels, and, inversely, with HL activity, lipemia, and triglyceride content of HDL2. The study suggests that HDL-cholesterol is not an independent parameter of lipid transport, but is strongly affected by triglyceride metabolism through lipolytic enzymes, as exemplified by postprandial lipemia that affect both composition and plasma levels of HDL2.

Studies of the role of B-cells in the resistance of mice to experimental candidiasis

The role of humoral immunity in experimental candidiasis was studied in B-cell-deficient mice. The B-cell deficiency was produced by administration of anti-mu antibodies to newborn animals. These anti-IgM-treated mice failed to produce antibodies against sheep red blood cells (SRBC), and their lymph nodes and spleens did not form germinal centres. However, their cell-mediated immune responses were normal as they developed delayed hypersensitivity to SRBC and rejected skin allografts like normal animals. These B-cell-deficient animals along with the controls were infected with one LD50 dose of Candida albicans. These animals were observed for mortality, antibody formation, delayed type hypersensitivity (DTH) to Candida antigen and viable count of the organism in different organs. The course of the experimental infection was almost parallel in both the groups. B-cell deficiency did not increase the susceptibility of the animals to experimental candidiasis.

The uses of the SEPA flap in the repair of defects in the hands and fingers

A series of 30 cases is presented in which the SEPA flap was used to provide skin cover for injuries and defects in the hand and fingers. Our experience with both unilateral and bilateral SEPA flaps confirms their reliability, convenience and versatility. The SEPA flap design can be used in conjunction with other flaps and in itself contributes to a more rational use of the skin of the lower abdomen in reconstructive surgery.

Studies of experimental candidiasis in T-cell-deficient mice

The role of cell-mediated immunity (CMI) in the protection against experimental murine candidiasis was studied. CMI-deficient animals prepared by adult thymectomy and treatment with antimouse thymocyte serum along with controls were challenged with one LD50 (6.6 X 10(4)) dose of Candida albicans. The course of infection in these animals was studied by mortality pattern, delayed type hypersensitivity reaction (DTH) to candida antigen, antibody formation, and viable count of organisms in kidney, spleen and liver at different time intervals. The T-cell-deficient animals were found to be highly susceptible to infection with C. albicans. A correlation was observed in the appearance of DTH and protection.

Dexamethasone-induced phosphorylation of high mobility group nonhistone proteins of aging rats

Phosphorylation of high mobility group (HMG) proteins and its modulation by dexamethasone were examined in vitro by incubating liver slices of young (15-) and old (138-week) male rats with (32P) orthophosphate. HMG proteins were extracted and analyzed by acid-urea polyacrylamide gel electrophoresis. Phosphorylation of HMG proteins, particularly of HMG2, 14 and 17 decreases drastically in old rats. Dexamethasone stimulates the phosphorylation of total HMG proteins in both ages. Individual HMG proteins vary in the extent of 32P incorporation. Such differential phosphorylation of HMG proteins and its modulation by dexamethasone may affect chromatin organization and gene expression during aging.

[Degradation of the insecticide parathion in soil]

Degradation of the insecticide Parathion in four types of soil from the Northeast of Brazil has been studied using radiometric techniques. In all the soil samples, sterilized or not, metabolites were detected with Rf values of 0.00 and 0.17 respectively--Silica Gel 60 F254 tlc plates (Merck); solvent system: hexane-acetone (4:1, v/v)--. However, 14CO2 was formed only with the non-sterilized soils and this was independent of the use or not of organic fertilizer. These results suggest that the two metabolites, mentioned above, are formed by a predominantly non-biological pathway, where as the formation of carbon dioxide requires the participation of the microbial flora of the soil. Analysis of the interaction of 14C-Parathion with soils shows that the extent of degradation of this insecticide is modified by adsorption on the soil particles.

Epithelial and basement membrane responses to chick embryo primitive streak grafts

Chick embryo primitive streak grafts, placed beneath the epiblast of host embryos, tend to result in the formation of either a neural plate in response to anterior streak grafts, or in de-epithelialization in response to posterior grafts. Ultrastructural and immunocytochemical examination shows that both reactions are preceded by basement membrane disruption and early removal of fibronectin therefrom. This disruption does not occur in response to non-streak grafts. It is suggested that the disruption, evoked by primitive streak cells, is a prerequisite first step, allowing direct graft-epiblast cell contact. This contact elicits a specific cytoskeletal reaction determining the epiblast response.

Insidious erosion of a digit by a ring

Avulsion injuries in fingers can be caused by rings worn on fingers. If the ring is tight, it can also cause an unusual problem, that of deep erosion into the finger. Only two cases with such erosion, both of them in adults have been reported so far. A child with a similar problem is presented here as a case report.

Cell mediated immune response following foot-and-mouth disease vaccination in buffalo calves

The cell mediated immune (CMI) response was studied by E-rosette formation in vitro and delayed type hypersensitivity (DTH) skin reaction in buffalo calves vaccinated with monovalent type 0 as well as with a polyvalent foot-and-mouth disease vaccine. Up to 35 days post-vaccination there was a significant increase (P less than 0.05) in the number of T-lymphocytes in both animal groups. Thereafter, the number of lymphocytes decreased. Delayed type hypersensitivity (DTH) skin reaction was characterized by a significant increase in skin thickness; histology showed mononuclear infiltration and perivascular cuffing.

Evaluation of intramuscular sulprostone and vacuum aspiration for termination of early pregnancy

The results of a comparative study of the efficacy and acceptability of sulprostone administered intramuscularly and vacuum aspiration for termination of very early pregnancy is reported. The period of amenorrhoea varied from 35 to 45 days with a positive pregnancy test. Group A (20 cases) received intramuscular sulprostone in doses of 500 micrograms and 1000 micrograms 4 hours apart without any pre-treatment. The success rate was 85%. Group B (20 cases) underwent vacuum aspiration with 100% success rate. Incidence of vomiting was comparable in both groups. Severe abdominal cramps/pain occurred in 11% following sulprostone administration. No immediate serious complication occurred. Estimation of serum HCG was done before sulprostone administration and 2 weeks later. A decline was noted 2 weeks post-treatment in successful cases, thus confirming the effectiveness of the therapy.

A manoeuvre to cover exposed metal using a de-epithelialised "turn-over" fasciocutaneous flap

This paper describes a technical manoeuvre to accommodate an exposed metal implant used in the treatment of a fracture of the tibia within a "turn-over" de-epithelialised fasciocutaneous flap. The need for such a procedure in this particular case is commented upon. A discussion is also included on the nature of the blood supply to the integument based on available information.

Postprandial lipemia. A key for the conversion of high density lipoprotein2 into high density lipoprotein3 by hepatic lipase

In this study, we have investigated the effects of alimentary lipemia in 15 normotriglyceridemic individuals on high density lipoproteins2 (HDL2) with respect to structure, composition, and substrate efficacy for hepatic lipase in vitro. In the study subjects, HDL2 levels ranged widely from 4.7 to 151.7 mg/dl plasma. HDL2 were isolated in the postabsorptive (pa) state and in the postprandial (pp) state, i.e., 7 h after ingestion of a standard fatty meal. In going from the pa state to the pp state, HDL2 exhibited higher flotation rates and lower densities due to a decreased proportion of protein (38.7----36.2%) and a higher abundance in phospholipid (32.5----34.9%). There was a variable increase in triglyceride at the expense of cholesteryl esters; this increase was correlated positively with the magnitude of pp lipemia (r = 0.69, P less than 0.01) and inversely with HDL2 levels (r = -0.72, P less than 0.01). Hdl2 fractions were incubated with human hepatic lipase in vitro. Product lipoproteins formed from lipolysis of pa-HDL2 and triglyceride-poorer pp-HDL2 were reduced in phospholipid content (by 25 and 50%, respectively) but remained in the size and density range of native HDL2. By contrast, a major fraction of triglyceride-richer pp-HDL2 was converted to particles with density, size, and apoprotein composition of native HDL3. Changes consistent with these findings in vitro were observed in vivo also, where 15 h postprandially, individuals with high-level lipemia showed a decrease in HDL2 and rise in HDL3, while those with lower-level lipemia did not. This study indicates that the magnitude of postprandial lipemia determines the proportion of triglyceride in pp-HDL2, which in turn determines whether or not HDL2 are converted to HDL3 by hepatic lipase action.

Symptomatic radiation-induced pericarditis in Hodgkin's disease

This is a retrospective review of 193 evaluable patients treated with radiation therapy to the mediastinum for Stages I, II and III-A Hodgkin's disease. Eligible patients were those receiving 3000 rad or more to the mediastinum and no chemotherapy prior to the radiation. During the study period, 13 patients developed symptomatic pericarditis. The interval post treatment to the development of symptoms was six to 34 months. The incidence of pericarditis was studied as a function of: (1) the dose of radiation at a depth of 2 cm, 5 cm and the midplane of the mediastinum; (2) the ratio of anterior to posterior weighting of dose; (3) the presence or absence of intrathoracic tumor; (4) the size of the tumor when present; and (5) the fraction of the heart exposed to the radiation beam. There was a significant increase in the incidence of pericarditis with an increased dose of radiation at 2 cm, 5 cm and midplane depths and also with the presence of a large intrathoracic tumor. A reduction in mediastinal dose is recommended.

Radical muscle mobilisation in the surgical repair of a unilateral cleft lip: a follow up report

This is a follow-up report on an earlier paper (Thatte, 1981) in which the idea of radical mobilisation of the orbicularis oris muscle in the treatment of unilateral cleft lip was presented. This paper includes eight late post-operative photographs of cases with unilateral cleft lip treated by radical mobilisation of muscle and suture without any recourse to incisions in the philtral area to gain height on the non-cleft side. Legends for the post-operative photographs describe our assessment of the results. Observations made while operating on these cases are noted. A discussion is included to view the manoeuvre of mobilisation of muscle against the background of existing methods of treatment of unilateral cleft lip. A postscript is added.

The culture of chick embryo mesoderm cells in hydrated collagen gels

Chick embryo mesoderm cells are various stages of differentiation were cultured in three-dimensional matrices of hydrated collagen. The tissues used were: stage 5 mesoderm from regions adjacent to the primitive streak; stage 12 mesoderm, comprising somitic, unsegmented (segmental plate) and lateral plate mesoderm; and stage 18 sclerotome. Explants were examined by phase contrast microscopy, including time-lapse, and scanning and transmission electron microscopy. The cells showed an increased ability to adhere to, and move in, the collagen gel with advancing stage. Of the stage 12 tissues, the unsegmented mesoderm was initially the slowest to grow out of the explant. Sclerotome cells showed by far the greatest ability to move within the gel. Where the collagen fibrils were randomly oriented, the cell morphology was polypodial and advancing lamellipodia showed clear undulations at their leading edges. A distinction was drawn between these undulations and the classical major ruffles which are seen in two-dimensional culture to uplift and pass back along the cell surface. The latter were not seen in the collagen matrix and were presumably suppressed by the three-dimensional culture configuration while the leading edge undulations were not. Ultrastructural examination showed that the cells possessed patches of amorphous material on their surface, which was sometimes interposed between the plasma membrane and collagen fibrils. Addition of hyaluronic acid (2 mg/ml) had an effect only the segmented mesoderm, where outgrowth was enhanced. Although the addition of plasma fibronectin (50 micrograms/ml) to the cultures did not affect any of the tissues, the removal of this substance, by antifibronectin antiserum or by the use of fibronectin depleted serum, inhibited outgrowth in most cases. The only tissue not reproducibly inhibited in this way was sclerotome. Alignment of the collagen fibres by the explants was observed, accompanied by an elongation of the outgrowing cells which, in bipolar form, preferentially moved up and down the aligned tracts. Scanning electron microscopy suggested that cell processes attached to, and presumably exerted tension on, bundles of fibrils thereby pulling them into line. Cell-to-cell contact was not accompanied by contact paralysis as judged by time-lapse micrography.

Action of acetylcholine on the atropinised heart of the frog during summer months

During summer months high doses of acetylcholine produced positive inotropic and chronotropic actions in 19 out of 22 preparations of atropinised perfused heart of the frog. Hexamethonium failed to block both the positive inotropic and chronotropic actions of Ach. Interestingly another ganglion blocking agent mecamylamine as well as beta adrenergic blocking agent propranolol blocked the positive inotropic action but not the positive chronotropic action.

The use of de-epithelialised "turn over" flaps in the hand

Two examples are presented of the application of the principles of de-epithelialised "turn over" flaps in the hand. These flaps were used to resurface a post-infective volar skin defect on a finger and to correct an adduction contracture in the first web space of the hand. The reasons for their use and their advantages are briefly discussed.

A survey of leprosy deformities in a closed community

Out of 1011 leprosy patients, 200 (20%) cases with permanent deformities were found in the Leprosy Control Unit, Raxaul (East Champaran), Bihar. The statistical data of selected patients and the types of various deformities are presented. The prevalence rate and incidence pattern of deformities reported by other workers are compared.

Effect of bladder distension on dosimetry in gynecological implants

In order to quantitate the impact of bladder distension on implant position and on radiation dosage to various parts of the bladder, 24 patients with gynecological neoplasms underwent computed tomographic scanning of the pelvis following insertion of afterloading intracavitary applicators. Shifting of the applicators due to bladder distension was measured at and two inches above the level of the vaginal ovoids. By maintaining a residual vesical volume of 200-300 ml with contrast material, radiation exposure to a large part of the bladder was reduced significantly while only a minor displacement of the implant system was noted.

Observation of cultured embryonic epithelial cells in side view

Epithelial cells from the early chick embryo were explanted and grown on a strip of coverglass which was positioned in a culture chamber in such a way that the cells could be filmed in side view. Ruffling of the cells at the leading edge of the sheet (marginal cells) appeared similar to the ruffles at the leading lamella of fibroblasts. The ruffles of the sub-marginal cells showed different characteristics, being longer and not propagated successively as were the marginal ruffles. Superimposition of cells was always the result of the active movement of a non-yolky cytoplasmic process underneath a yolky process (i.e. underlapping). The non-yolky processes appeared to be strongly adherent to the substrate in comparison with the yolky processes, which were easily displaced. Active movement of cells or lamellae on the dorsal surface of the sheet was never observed. Preliminary ultrastructural evidence is presented which suggests that the strongly adherent non-yolky processes possess well-defined microfilament tracts associated with the ventral plasma membrane, while the poorly adherent processes do not possess such tracts.

Effect of a conditioning method on general safety test in guinea pigs

Prior to utilization for safety tests, one group of guinea pigs was selected after a 1-week conditioning period, on the basis of physical appearance and a 5% body weight gain. Those in a second group were selected shortly after being received, on the basis of their physical appearance. All guinea pigs were maintained under identical management conditions during the safety tests. The number of guinea pigs that gained weight from both groups were compared. The conditioning method used resulted in significant (p less than 0.001) increase in the number of guinea pigs that maintained or increased body weight during general safety tests.