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Tropical forests are rapidly disappearing due to the expansion of cash crops to meet demands from distant markets. Pressing concerns on deforestation impacts resulting from the global trade of tropical commodities have led some high-income countries’ governments to consider diverse regulatory and trade levers to tackle the problem. These include proposals for new supply chain due diligence legislation concerning imports of forest-risk products and the inclusion of environmental measures in trade deals. To contribute to this debate, we conducted a comprehensive analysis of existing data on global trade and consumption patterns of tropical commodities, attribution of commodity production to deforestation, trade agreements, and progress in the implementation of crop sustainability standards. We used global data on key tropical commodities of oil palm, cocoa, and coffee. Our study shows that high-income countries have the highest per capita consumption for the three commodities evaluated and that consumption rates have dramatically increased in the last two decades. We discuss a range of measures that can potentially be required to tackle deforestation in global supply chains, which are currently being considered by policymakers, before discussing the kinds of post-growth, convivial approaches that are often excluded by the framing. Given the inherent expansionary nature of global market dynamics, we show that market-based initiatives are inadequate to tackle continuing deforestation and socio-ecological degradation. More transformative solutions amplify commoning and post-growth approaches are required to lead to some uncoupling of trade and territorialising of economic activity to fit within planetary boundaries and allow for plural values.

The total and individual glycosaminoglycan (GAG) content at various stages of the Dupuytren disease process and in samples of normal palmar connective tissue (palmar dermis, palmar fascia and digital flexor tendon) from the hands of uninvolved age-matched controls have been assayed and compared. Morphological comparisons between the different tissues were made by histological examination of sections stained to demonstrate collagen fiber patterns and glycosaminoglycan distribution.Significant differences in the type and amount of GAG were found between the various manifestations of the disease process, i.e., nodules, cellular and fibrous bands, and between these and the normal palmar connective tissues.In the most actively proliferating cellular regions chondroitin sulfate levels were 11 times greater than those of the normal palmar connective tissues, whereas dermatan sulfate tissue levels showed a fourfold increase. On the other hand, tissue concentrations of hyaluronate were similar to those of normal palmar connective tissue.The relationship of these differences in GAG levels to the development and maturation of the normal palmar connective tissues and the Dupuytren's process is discussed.

This combined biochemical and histological study demonstrated that subcutaneously implanted Goretex tubing can be used to monitor and detect variations in wound healing potential in rats subjected to experimental hypoproteinaemic and normal refeeding conditions. Induced hypopro-teinaemia was observed to be associated with a marked diminution in cellular infiltration, collagen synthesis and fibrous deposition within the implant. All these effects were completely reversed by subsequent refeeding of normal diet. Although regional variations in fibroblastic response attributable to biologic variability, were observed within individual control implants, or between paired controls, they were relatively minor as compared to the marked differences observed at the macroscopic, microscopic and biochemical level between implants removed from normally fed and protein deficient animals.

The physical forces acting on the flexor digitorum profundus tendon of the rabbit were altered by anterior translocation of the tendon. The glycosaminoglycan (GAG) content was determined in regions of the tendon previously under tension or previously subjected to pressure. There was an increase in the GAG content in the original tension transmitting region. Initially this was due to increased hyaluronic acid and chondroitin sulfate content during the early remodeling phase. Later when tension was restored to the translocated tendon, the content of these two GAG decreased to normal values while the high overall GAG concentration was maintained by increased amounts of dermatan sulfate. Finally the dermatan sulfate content and the total GAG content returned to normal values.The original pressure bearing region showed a rapid loss of total GAG. This was mainly due to a loss of chondroitin sulfate component, and eventually the region showed a GAG composition similar to that of normal tension transmitting tendon. Replacement of the translocated tendon to its normal position resulted in a slow replacement of the GAG, particularly chondroitin sulfate, in the pressure bearing region. The extent of recovery appeared to be dependent on the length of time the tendon had been left in the translocated position. Attempts to form a new pressure bearing structure in another part of the tendon also resulted in changes in the proportions of the GAG, but little change in total GAG content.

Extensive data on the glycosaminoglycan (GAG) composition and the collagen fibril diameter distribution have been collected for a diverse range of connective tissues. It is shown that tissues with the smallest diameter collagen fibrils (mass‐average diameter < 60 nm) have high concentrations of hyaluronic acid and that tissues with the largest diameter collagen fibrils (mass‐average diameter ∼200 nm) have high concentrations of dermatan sulphate. It is suggested that the lateral growth of fibrils beyond a diameter of about 60 nm is inhibited by the presence of an excess of hyaluronic acid but that this inhibitory effect may be removed by an increasing concentration of chondroitin sulphate and/or dermatan sulphate. It is also postulated that high concentrations of chondroitin sulphate will inhibit fibril growth beyond a mass‐average diameter of ∼150 nm. Such an inhibition may in turn be removed by an increasing concentration of dermatan sulphate such that it becomes the dominant GAG present in the tissue.

Isolated single fascicles from tail tendons of young rats were freed of epitenon cells and cultured in vitro for up to 7 days. The tissue remained viable, as judged by the structural integrity of cell organelles and the ability to synthesize DNA and glycosaminoglycans (GAG). The rate of DNA synthesis peaked after 2 days in culture and decreased slowly thereafter. Concomitantly, an increase in cell number was noted at the periphery of the fascicle. GAG production also increased during culture, sulphated GAG being increased proportionately more than hyaluronic acid. Dermatan sulphate was the predominant sulphated GAG in freshly isolated fascicles, but in cultured tissue, the newly synthesized sulphated GAG was more sensitive to degradation by chondroitinase AC and had an increased electrophoretic mobility. Fine structural changes were observed in cultured tissues such as the retraction of cell processes. rounding up of cell bodies and the appearance of gaps between collagen fibrils. Cultured tenocytes also frequently contained apparently phagocytized collagen fibrils which were not seen in freshly isolated fascicles, and this appearance was suggestive of collagen degradation occurring in vitro, although no change in the total hydroxyproline content was noted. The data show that when individual fascicles are cultured in vitro they undergo a process of matrix remodelling which has features in common with events occurring in vivo when tendons have been surgically manipulated.

Chick embryo epiphyseal chondrocytes cultured in media containing HEPES, TES, and BES zwitterion buffers, used in combination or independently, consistently developed cytoplasmic vacuoles. This cytoplasmic vacuolation was resolved when the zwitterion buffered media was replaced by media containing bicarbonate:CO2enriched air buffer. Vacuoles were infrequent or absent in cultures grown in bicarbonate:CO2enriched air. Chondrocytes with an established extracellular matrix showed less vacuolation than fibroblastlike and polygonal shaped cells that lacked such a matrix. The granular endoplasmic reticulum and Golgi dictyosomes of zwitterion buffered chondrocytes were distended and contained a flocculent amorphous material. Cytoplasmic vacuoles (0.5 to 3.0 μm diam) formed by the fusion and intracellular accumulation of Golgi vesicles and vacuoles also contained a flocculent material enhanced by ruthenium red. Membrane bound extracellular vacuoles containing ruthenium red stained proteoglycan aggregates were common in the extracellular matrix of zwitterion buffered cultures but were generally absent from bicarbonate treated cultures. Electron dense calcium deposits seemed much larger and more numerous in the presence of zwitterion buffers.

Although collagen of either tendon or dermis can be stained equally well with Ponceau 2R/Acid Fuchsin or Light Green SF if the dyes are used independently, tendon collagen retains the red dye mixture and dermal collagen the green counterstain when the dyes are used sequentially in the Masson trichrome procedure. The results of experiments designed to assess differences in the penetration, retention and displacement of these arylmethane dyes have demonstrated that they are retained more firmly by the tensioned collagen of tendon or stretched dermis, and are more easily displaced from the collagen of relaxed tendon or dermis. Experiments designed to test the basis of these differences in dye retention indicate that more positively-charged amino dye-binding sites are available in the tensioned collagen than in relaxed collagen, where they appear to be closely associated with adjacent carboxyl groups on the collagen fibres. The possibility that the carboxyl groups of associated acid mucopolysaccharides are implicated in the differences in staining propensity has been investigated and discounted. It is suggested that whereas the binding of arylmethane dyes to collagen under tension is through strong ionic linkages to amino groups, the binding of these and other dyes to relaxed collagen is through weaker hydrogen bonds. It is proposed that these differences in charge distribution on the collagen of the two situations is related to the previously described piezo-electric effect demonstrable on stretched collagen.

Although normally, dermal collagen fails to retain the Ponceau 2R/Acid Fuchsin component of the Masson trichrome procedure and is stained green by the counterstain, the collagen of sections of human dermis which have been heated above its denaturation temperature (Ts) in moist conditions will retain the initial red stain. This difference in dye retention appears to be related to conformational changes of the collagen molecule which are associated with denaturation, for the change in staining is directly related to the shrinkage temperature, is reversed by rapid cooling after heating, is profoundly affected by differences in environmental conditions during heating which affect molecular rearrangement, and is age-dependent. Analogous changes in staining propensity have been observed in heated keratin and epidermis. However, whereas the retention of the initial red dye mixture is increased in denatured dermis, it is diminished in heated epidermis. It is suggested that the subtle dye substrate interaction of the Masson trichrome staining procedure can be utilized to demonstrate changes in molecular configuration which are associated with thermal, as well as other forms of denaturation of collagen and other proteins.

1. The indications for amputation of all the toes for severe toe deformity in rheumatoid arthritis, hallux valgus and pes cavus are discussed.2. The results of forty-seven amputations in twenty-eight patients are analysed: 93 per cent were found to be very satisfied with the operation.3. The technique of the operation and the subsequent management are described. The importance of retaining full-length shoes fitted with metatarsal insoles and toe blocks to preserve a good gait and balance is emphasised.

1. Recurrence of deformity after operations for drop foot is often associated with opening of the front of the ankle joint: this has previously been regarded as a complication of the operation.2. This study of sixty paralytic drop feet treated conservatively reveals that this laxity was in fact present in no less than 43 per cent.3. The laxity is most commonly found when the calf muscle is strong and it can occur within a year of the onset of the paralysis. It is not always prevented by wearing a toe-raising spring.4. Such anterior laxity may well be a common cause of failure of many of the standard operations for drop foot.5. Before operation for drop foot is undertaken a lateral radiograph of the ankle should be taken in forced plantar-flexiori. If this demonstrates anterior laxity any standard operation is unlikely to succeed unless the anterior fibres of the collateral ligaments are protected from strain by simultaneous tendon transplantation or unless the ankle is included in the arthrodesis.

The effects of the release of normal distractive forces from the rabbit’s tendo-achilles by distal tenotomy and proximal sciatic neurectomy alone, and in combination, have been studied. The results demonstrate that: Complete release of distractive forces from the tendon is followed by changes in collagenous architecture and an increase in cell size and cell population, particularly at the musculotendinous junction.The changes in the resident cell population and the cells migrating into the tendon from the musculo-tendinous junction and perivascular spaces are associated with the production of increased quantities of mucopolysaccharide and the disaggregation of collagen fibres in the vicinity.In the initial stages this increased mucopolysaccharide appears to be predominantly unsulphated material – probably hyaluronic acid, but with the reapplication of tension which follows spontaneous repair of the divided tendon, this is replaced by a sulphated polymer which appears to be associated with the reaggregation of collagen fibres at this stage.The implications of this biphasic production of mucopolysaccharide, and its effect on the stability and integration of collagen, are discussed.During this study it was found that the Masson’s trichrome stain appears to be a precise indicator of the state of tension of collagen fibres within the tendon, and other connective tissues.