A new blue whale song-type described for the Arabian Sea and Western Indian Ocean

Blue whales Balaenoptera musculus in the Indian Ocean (IO) are currently thought to represent 2 or 3 subspecies (B. m. intermedia, B. m. brevicauda, B. m. indica), and believed to be structured into 4 populations, each with a diagnostic song-type. Here we describe a previously unreported song-type that implies the probable existence of a population that has been undetected or conflated with another population. The novel song-type was recorded off Oman in the northern IO/Arabian Sea, off the western Chagos Archipelago in the equatorial central IO, and off Madagascar in the southwestern IO. As this is the only blue whale song that has been identified in the western Arabian Sea, we label it the ‘Northwest Indian Ocean’ song-type to distinguish it from other regional song-types. Spatiotemporal variation suggested a distribution west of 70°E, with potential affinity for the northern IO/Arabian Sea, and only minor presence in the southwestern IO. Timing of presence off Oman suggested that intensive illegal Soviet whaling that took 1294 blue whales in the 1960s likely targeted this population, as opposed to the more widely distributed ‘Sri Lanka’ acoustic population as previously assumed. Based upon geographic distribution and potential aseasonal reproduction found in the Soviet catch data, we suggest that if there is a northern IO subspecies (B. m. indica), it is likely this population. Moreover, the potentially restricted range, intensive historic whaling, and the fact that the song-type has been previously undetected, suggests a small population that is in critical need of status assessment and conservation action.

A disease severity scale for systemic sclerosis: development and testing

OBJECTIVE

To develop and test a severity scale for individual organ involvements in systemic sclerosis (SSc, scleroderma).

METHODS

An international study group completed the following tasks: (1) developed a glossary of terms including all pertinent variables for 9 potentially affected organ systems; (2) collected prospective data to determine the feasibility and practicality of each proposed variable; (3) revised the initial list of variables; (4) determined the association of each variable with mortality (a proxy for morbidity) using 579 patients in an existing comprehensive longitudinal scleroderma databank; (5) developed a severity grading scale for each organ system by discussion and consensus; and (6) externally validated the scale using an independent group of 680 patients from the same databank.

RESULTS

Nine organ-specific severity scales were developed from 0 (no documented involvement) to 4 (endstage disease). The data required for scale completion are relatively easy and practical for all physicians to obtain.

CONCLUSION

This preliminary severity scale will be useful for assessing disease severity status in individual patients both at one point in time and longitudinally. The severity scale will assist in the design and conduct of clinical trials and the comparison of study populations with one another. The scale will serve as a framework for developing a scleroderma disease activity index.

Thrombospondin 1 is expressed by mesenchymal cells in mouse post-natal skin and hair follicle development

Thrombospondin 1 is an extracellular matrix glycoprotein with multiple functions. In the skin, it has been immunolocalized to basement membrane, and its expression increases during embryogenesis and wound healing. Its normal cellular source in the skin is not known, except during wound healing, where macrophages and keratinocytes seem to be the primary source. We have analysed the expression of thrombospondin 1 mRNA in normal mouse skin at different ages by in situ hybridization. It was found that the mRNA is expressed by dermal mesenchymal cells and mature fibroblasts and developmentally regulated during post-natal skin growth and morphogenesis. In adult mouse skin, expression of the thrombospondin is restricted to the mesenchymal cells of hair follicle papilla. These results suggest that the regulation of thrombospondin 1 transcription in mesenchymal cells can play an important role in post-natal skin development. Its mRNA expression is a characteristic of adult dermal papilla cells with a potential role in hair development.

Quinolinic acid accumulation in injured spinal cord: time course, distribution, and species differences between rat and guinea pig

Experimental compression injury of the spinal cord in guinea pigs results in delayed neurologic deficits that continue to increase in severity for several days following trauma, coincident with inflammatory responses, including invasion of the lesion by mononuclear phagocytes and increased levels of the neurotoxin quinolinic acid (QUIN). Inflammatory responses and QUIN elevation also occur following spinal cord contusion in rats, but maximal neurologic deficits develop immediately. In this study, somatosensory evoked potentials (SEP) and tissue, serum, and cerebrospinal fluid levels of QUIN were measured in guinea pigs and rats following similar compression injuries of the thoracic spinal cord. SEP changes differed between the species, consistent with other neurological changes. In guinea pigs, increases in QUIN levels at the lesion site began at 1 day postinjury, achieved maximal elevation (100-fold) by 12 days, then declined, but remained above serum levels at 25 days postinjury. A similar increase occurred in adjacent areas of the spinal cord, with lower peak levels. In rats, tissue QUIN at the center of the lesion remained below serum levels at all times, increasing moderately (<10-fold) up to 7 days, then decreasing between 7 and 25 days. These data demonstrate differences in the time course and magnitude of QUIN accumulation and neurological deficit between guinea pig and rat, which may relate to differences in secondary pathological mechanisms. Such profound differences may affect the use of these species for evaluation of experimental therapy in this and other inflammatory conditions of the central nervous system.

Sexual function and erection capability among young men with spina bifida

In a study of sexual function and erection capability, 15 young men with spina bifida were interviewed, underwent physical examination, and completed two consecutive night recordings of penile tumescence and rigidity with the Rigi-Scan (Dacomed Inc.). Eleven reported erections with stimulation. Rigi-Scan data showed that two subjects (both with lesions at the sacral level) had normal numbers and durations of erections, that seven others had abnormally brief and infrequent nocturnal erections, and that six had none. Ten subjects had at least 'some' glans sensation on physical examination. Self-reported erection capability was related to motor level and glans sensation. The number of nocturnal erections was related to sensory level. The study suggests that lower motor and sensory levels are associated with greater potential sexual function in males with spina bifida.

Autoantibodies to fibrillarin in systemic sclerosis (scleroderma). An immunogenetic, serologic, and clinical analysis

OBJECTIVE

To determine the frequency, clinical associations, and any major histocompatibility complex correlations of antifibrillarin antibodies in patients with systemic sclerosis (SSc).

METHODS

Antifibrillarin antibodies were determined by indirect immunofluorescence, immunoblotting, and immunoprecipitation, and HLA class II alleles by DNA oligotyping, in a large cohort of SSc patients.

RESULTS

Antifibrillarin was found in 8% of 335 SSc sera and was significantly more common in blacks (16%) than whites (5%), in males (33%) than females (14%), and in patients with cardiac, renal, or gut involvement. The HLA class II haplotype DRB1*1302, DQB1*0604 was found significantly more frequently in SSc patients with antifibrillarin compared with race-matched normal controls and 260 SSc patients without antifibrillarin. In addition, 1 or more of the HLA-DQB1 alleles *0604, *0301, *0602, and/or *0302 was found in all antifibrillarin-positive patients, and 62% of the antifibrillarin-positive patients had 2 of these HLA-DQB1 alleles, a highly significant difference from both race-matched normal controls and antifibrillarin-negative SSc patients.

CONCLUSION

Antifibrillarin, although an infrequent nucleolar autoantibody, is a marker for severe SSc, especially in blacks and males, and is strongly associated with a unique HLA haplotype, as well as with combinations of certain HLA-DQB1 alleles.

Elevated levels of platelet derived growth factor and transforming growth factor-beta 1 in bronchoalveolar lavage fluid from patients with scleroderma

OBJECTIVE

Systemic sclerosis (scleroderma, SSc) frequently affects the lungs, and interstitial pulmonary fibrosis is one of its major complications. The pathophysiology of SSc lung disease s poorly understood, but recent studies document an inflammatory process resembling that of idiopathic pulmonary fibrosis with increased numbers of activated alveolar macrophages and granulocytes in bronchoalveolar lavage (BAL) fluid). We determined levels of 2 potentially important mediators of fibroproliferative repair in BAL fluid from patients with SSc.

METHODS

Using Western blot and ELISA techniques we measured levels of platelet derived growth factor (PDGF) and transforming growth factor-beta (TGF-beta in BAL fluid from patients with SSc and healthy controls. The mitogenic effect of these cytokines on SSc lung myofibroblasts was determined by [3H]thymidine incorporation.

RESULTS

SSc BAL fluid contains significantly elevated levels of PDGF-AA and PDGF-BB. Where TGF-beta 1 was significantly elevated in SSc lavage fluid, the amount of TGF-beta 2 was significantly less than that observed in normal lavage fluid. Myofibroblasts cultured from SSc lavage fluid exhibited enhanced [3H]thymidine incorporation upon exposure to the growth factors present in SSc BAL fluid: PDGF and TGF-beta 1. SSc lung myofibroblasts pretreated with TGF-beta 1 exhibited an enhanced mitogenic effect upon stimulation by PDGF, due in part to the induction of the PDGF alpha receptor.

CONCLUSION

Our studies support a role for PDGF and TGF-beta 1 in the pathogenesis of SSc lung disease.

Fasciitis (not scleroderma) following prolonged exposure to an organic solvent (trichloroethylene)

We describe 2 cases of diffuse fasciitis with eosinophilia (DFE) associated with prolonged exposure to the industrial solvent trichloroethylene (TCE). The medical and personal histories, examinations, and laboratory and pathological investigations were reviewed and summarized. The 2 case reports, representing the first and 2nd cases of DFE associated with TCE, were compared with 8 reported cases of systemic sclerosis associated with TCE and suggest a direct association between TCE exposure and the development of fasciitis (DFE).

Lupus and its management

The recognition and treatment of SLE requires an approach similar to other chronic diseases. A thorough initial evaluation with regular monitoring of outwardly silent manifestations (e.g. renal) minimizes potentially devastating complications. For disease which does not threaten the patient's life or carry the threat of end-organ failure, treatment analogous to non-lupus patients is usually appropriate, including minimization of steroids. The widening use of cytotoxic agents promises to continue to decrease the mortality from SLE. These agents must be used sparingly and in consultation with a rheumatologist to reduce the incidence of infection, malignancy and sterility.

Differential responses of human papillary and reticular fibroblasts to growth factors

Differences in the responses to growth factors of normal fibroblasts and scleroderma fibroblasts have been demonstrated previously. Because human dermal fibroblasts are heterogeneous populations, whether known differences between papillary and reticular dermal fibroblasts could account for the noted differences between normal and scleroderma fibroblasts was investigated. Papillary dermal fibroblasts were grown from a dermatome section of normal skin from an adult donor. Reticular dermal fibroblasts were cultured from punch biopsy specimens taken from the same location. In vitro, papillary dermal fibroblasts proliferated more rapidly, had a higher mitotic index and reached greater density at confluence, confirming previous observations. The reticular dermal fibroblasts were more dendritic. Reticular dermal fibroblasts had higher rates of tritiated thymidine uptake and larger increases in mitotic index in response to isoforms of platelet-derived growth factor (PDGF). The characteristic response of scleroderma fibroblasts, potentiation of the mitogenicity of PDGF AA by transforming growth factor-beta (TGF-beta), was not observed in either cell type. Therefore, the phenotypic characteristics of scleroderma fibroblasts cannot be explained by an unusual admixture of papillary and reticular fibroblasts.

Growth and characterization of fibroblasts obtained from bronchoalveolar lavage of patients with scleroderma

We describe the detection and the growth of fibroblasts with human smooth muscle cell differentiation features from bronchoalveolar lavage (BAL) fluid of 53% of patients with scleroderma, but not from healthy controls. The binding of alpha-actin, vimentin and desmin antibodies by scleroderma lung fibroblasts exceeded that of normal adult lung fibroblasts, indicating that scleroderma lung fibroblasts express some markers of human smooth muscle cell differentiation (myofibroblasts), which may account for differences in biological behavior. A mesenchymal cell phenotype was documented by mRNA analysis, showing high expression of collagen type I and fibronectin in these cells. Fibronectin is also released in significantly higher amounts by scleroderma alveolar macrophages than by macrophages from healthy donors.

Fibronectin release by systemic sclerosis and normal dermal fibroblasts in response to TGF-beta

To determine whether enhanced matrix synthesis by systemic sclerosis (SSc) fibroblasts in vitro is due to increased responsiveness to transforming growth factor-beta (TGF-beta), fibronectin release by SSc and normal fibroblasts (7 pairs) was measured at various concentrations of TGF-beta. In the absence of TGF-beta, SSc fibroblasts released 30 +/- 22% more fibronectin than normal fibroblasts. While both SSc and normal fibroblasts increased fibronectin release at all concentrations of TGF-beta tested, the percentage increases were not statistically greater for the SSc fibroblasts even though 4 of the SSc fibroblasts strains were selectively sensitive to low concentrations of TGF-beta. TGF-beta increased cell numbers of both SSc and normal strains equally. Our data confirm abnormal regulation of fibronectin gene expression in SSc fibroblasts and suggest increased sensitivity to TGF-beta by some SSc fibroblast strains.

Ascorbate effects on type I procollagen synthesis by human adult skin fibroblasts: different migration positions of type I procollagen chains on SDS polyacrylamide gel after incubation with ascorbate

The effects of ascorbate and steroids on type I procollagen synthesis by human skin fibroblasts were studied. Ascorbate treatment (50 micrograms/ml) for 24 hours stimulated a 2-3 fold increase in type I procollagen synthesis and an unexpected shift in the mobility of type I procollagen on SDS polyacrylamide gels. The kinetics of the increase in procollagen synthesis (4 hours) and the shift in electrophoretic mobility (1 hour) were dissimilar, suggesting different controlling mechanisms. This was confirmed by the addition of alpha-alpha'-dipyridyl to ascorbate-treated cultures which eliminated the ascorbate-induced shift in electrophoretic mobility without altering the amount of procollagen synthesis. In contrast, hydrocortisone (1.5 microM) reduced the ascorbate-induced stimulation of type I procollagen synthesis by 80% but did not affect the ascorbate-induced shift in electrophoretic mobility. These studies indicate that the ascorbate-induced increase in type I procollagen synthesis is due to increased levels of type I procollagen mRNA and is independent of the level of hydroxylation of the procollagen.

Endothelial injury in scleroderma. A protease mechanism

The mechanism of action of the previously reported serum ECA in patients with scleroderma has been studied. Gel filtration (Sephadex G-200) followed by ion exchange chromatography (DEAE-Sephadex A-50, Tris buffer, pH 8, 1.5M NaCl) yielded a 13-fold enriched fraction. ECA biological activity was abolished by preincubating the active fraction with several protease inhibitors (STI, aprotinin, TLCK, and PMSF); exposure of target cells to protease inhibitors did not inhibit ECA. ECA-rich fractions have esterolytic activity (3H-TAME), which was irreversibly inhibited by TLCK and PMSF in a time-, temperature-, concentration-, and pH-dependent fashion. In separate studies, functional protease inhibitor activity in scleroderma sera was determined by the capacity of serum to inhibit BAPNA hydrolysis by trypsin (TIC). TIC was 1.32 +/- 0.15 (milligrams of trypsin inhibited by 1 ml of serum +/- S.D.) in 20 control sera, and 0.54 +/- 0.18 (p less than 0.001) in 38 scleroderma sera. A positive correlation was found between TIC and percent inhibition of endothelial cell 3HTdR uptake induced by the same serum (r = 0.94, p less than 0.001). These studies suggest that ECA is mediated in vitro via a protease mechanism associated with a functional deficiency of protease inhibitors in scleroderma sera.

A prospective study of Raynaud phenomenon and early connective tissue disease. A five-year report

To define features of patients with Raynaud phenomenon that predict the evolution of connective tissue disorders, a prospective study was initiated. Patients with history or physical evidence of Raynaud phenomenon without causal or associated disorders underwent initial multisystem evaluation. Scleroderma (systemic sclerosis) of less than five years' duration was included for comparison. Patients were classified as having Raynaud phenomenon "only," undifferentiated connective tissue syndrome or scleroderma. Nailfold capillary microscopy was performed, and patterns were scored blindly from coded photographs. Of 91 patients with Raynaud phenomenon entered (Raynaud phenomenon only, n = 49; undifferentiated connective tissue syndrome, n = 22; scleroderma, n = 20), abnormal "scleroderma pattern" capillaries were noted in seven of 49, 19 of 22 and 19 of 20, respectively (p less than 0.005). Of 39 patients with Raynaud phenomenon only followed (mean duration, 23.7 months) undifferentiated connective tissue syndrome developed in three. Of 17 patients with undifferentiated connective tissue syndrome followed (mean duration, 27.6 months), six patients had transitions (four scleroderma; one scleroderma-systemic lupus erythematosus overlap; one SLE). Nailfold capillary abnormalities best identified transitional patients in both groups (eight of nine) and were more sensitive than ANA (six of nine), presence of digital ulcers (four of nine) or decreased esophageal motility (two of nine). This prospective study documents a useful role for capillary examinations in evaluating Raynaud phenomenon. Abnormal capillaries indicate an increased risk for connective tissue disease; normal capillaries favor idiopathic Raynaud phenomenon.

Elevated levels of circulating platelet aggregates and beta-thromboglobulin in scleroderma

Levels of circulating platelet aggregates and plasma beta-thromboglobulin reflect the degree of platelet activation in vascular injury and repair. Both values were evaluated in 38 patients with scleroderma and 18 control subjects matched for age, sex, and race. Circulating platelet aggregates (expressed as percentage of total platelet count) were 7.2 +/- 5.5% (mean +/- SD) in the control group and 31.2 +/- 13% in the scleroderma group (p less than 0.0005). Beta-thromboglobulin levels in the control groups were 20 +/- 10 ng/mL and 72.7 +/- 50 ng/mL in the group with scleroderma (p less than 0.0005). A positive correlation was found between the two values (r = 0.6, p less than 0.0005). Significant reductions in circulating platelet aggregates and beta-thromboglobulin levels were achieved in 10 patients by dipyridamole and aspirin therapy. These results show in-vivo activation of platelets in scleroderma with release of platelet granule constituents. Antiplatelet therapy in adequate doses returned both values to normal; however, its long-term effect on scleroderma is not yet known.

Variable response to oral angiotensin-converting-enzyme blockade in hypertensive scleroderma patients

Twelve scleroderma patients with hypertension, seven of whom had malignant hypertension and renal failure of scleroderma renal crisis, were treated with captopril. The first dose lowered mean pressure in all patients by 21.3 mmHg; in 6 patients it relieved encephalopathy. Blood pressure was controlled in all patients. Two of 7 patients with scleroderma renal crisis had improvement in renal function; the 5 patients who did not have malignant hypertension improved or stabilized. Despite good pressure control, however, renal failure developed in 5 patients with scleroderma renal crisis. The data indicated that captopril is effective antihypertensive therapy in scleroderma and, when given early, may prevent renal failure and death.

Fibroblast selection in scleroderma. An alternative model of fibrosis

Human preputial skin fibroblasts were cloned in vitro, and studies in 21 clones were shown to exhibit a 3-fold difference in collagen synthesis; this heterogeneity of phenotypic expression was conserved over multiple population doublings. When the clones were exposed to sera from 10 scleroderma patients, selective growth of high-collagen-producing fibroblasts was observed. Prostaglandin E2 abrogated the selective effect of scleroderma serum on high-collagen-producing fibroblast clones. Besides enhanced collagen synthesis, these clones of normal fibroblasts shared an insensitivity to feeding schedule with fibroblasts from scleroderma skin. These data raise the possibility that scleroderma represents a process of selection of fibroblasts programmed to produce increased amounts of collagen.

Precursor-size components are the basic collagenous subunits of murine tumor basement membrane

The acid-insoluble fraction of murine tumor basement membrane produced by the EHS sarcoma was extracted following reduction of disulfide bonds under non-denaturing conditions. Extracts prepared from tumors grown in either lathyritic or normal animals contain two procollagen-like chains as well as cross-linked oligomers of these chains. Extracted monomeric chains behave almost exactly like reduced, radiolabeled EHS collagen precursor chains on SDS-PAGE and SDS-agarose suggesting that they are very similar collagens. Since the collagen extracted after reduction represented a significant proportion of the total tumor collagen, it is likely that tumor basement membrane is assembled from precursor-size Type IV collagen molecules.

Chromosome breakage and sister chromatid exchange frequencies in scleroderma

Peripheral lymphocytes from 3 scleroderma patients with systemic disease and from 3 normal controls were examined for frequencies of chromosomal aberration and sister chromatid exchange (SCE). Significant increases in the levels of chromosomal anomaly and SCE were found for all 3 patients. These results are discussed in terms of the diagnostic potential of SCE in scleroderma and the possible etiologic role of cytogenetic instability in this disease.

DNA binding activity of serum from patients with systemic lupus erythematosus

The reaction conditions essential for reproducible use of the cellulose ester membrane filter assay for anti-DNA antibody levels in patients with systemic lupus erythematosus are described. A dependence of DNA-binding capacity on serum concentration was observed in the assay, requiring that serum concentrations be comparable in determinations of DNA-binding activity of different sera and when comparing different published studies. The DNA-binding capacity of serum from lupus patients was found to be significantly different from that of healthy controls. However, the binding capacities were not significantly different between lupus patients with and without nephritis. The relative avidity of the anti-DNA antibodies were estimated from plots of 1/DNA bound vs 1/DNA free and these data indicate that the avidities of the antibodies from the two groups of lupus patients are not significantly different. This observation suggests that the tightness of binding between the DNA and the serum anti-DNA antibodies cannot be used to predict immune complex-induced nephritis in lupus patients.

Blood viscosity, plasma proteins, and Raynaud syndrome

The rheology of the blood was studied in 20 patients with Raynaud syndrome. Sixteen patients had scleroderma, two had nonspecific angiitis, one had systemic lupus erythematosus, and one had Raynaud disease. Viscosity measurements were performed on whole blood, plasma, and suspensions of 45% red blood cells (RBCs). In autologous plasma, over a wide range of shear rates. The relative viscosity, an index of RBC aggregation, was obtained by dividing the RBC viscosity in autologous plasma (at a hematocrit value of 45%) by the plasma viscosity. Concentrations of the plasma globulins and fibrinogen were also measured. The mean plasma viscosity was significantly (P less than .01) elevated over established normal controls. The mean RBC viscosity and the relative viscosity were significantly (P less than .01) elevated over normal controls, as were fibrinogen and the globulins. These studies demonstrate increased blood viscosity and red blood cell aggregation, which may constitute an important hindrance to flow.

Connective tissue synthesis by scleroderma skin fibroblasts in cell culture

Skin fibroblasts from subjects with scleroderma and control subjects were grown in tissue culture to compare the characteristics of connective tissue metabolism. A striking increase in soluble collagen (media hydroxyproline) was observed in eight of nine scleroderma cultures when they were compared with identically handled control cultures matched for the age and sex of the donor and the anatomic site of the donor skin. Glycoprotein content as estimated by hexosamine and sialic acid was also significantly increased in the scleroderma cultures. Estimations of protein-polysaccharide content by uronic acid determinations were low in all cultures and not significantly increased in scleroderma cultures. This report demonstrates the feasibility of using fibroblast cell cultures to study chronic rheumatic and connective tissue disorders. The initial results suggest a net increase in collagen and glycoprotein synthesis in scleroderma fibroblast cultures. The implications of an abnormality of connective tissue metabolism by skin fibroblasts propagated in vitro in the acquired disorder scleroderma are discussed.