Progressive supravenous granulomatous nodular eruption in a human immunodeficiency virus-positive intravenous drug user treated with highly active antiretroviral therapy

We describe a 41-year-old human immunodeficiency virus-infected woman with a previous history of intravenous drug abuse, who developed multiple linear nodules following the superficial veins on both arms. Histopathological examination disclosed a dermal histiocytic inflammatory reaction with sarcoid-like granuloma formation occasionally showing an intracytoplasmic refractile material in the histiocytic cells. Nodular lesions developed progressively after starting on highly active antiretroviral therapy (HAART) which increased her CD4 cell count and suppressed her viral load. The appearance of latent inflammatory or autoimmune disease following HAART is a well-recognized phenomenon. We consider that this peculiar 'progressive supravenous granulomatous nodular eruption' should be included within the spectrum of the so-called immune reconstitution inflammatory syndrome.

Relationship among densitometry, bone histomorphometry, and histologic stage in idiopathic myelofibrosis

Idiopathic myelofibrosis (IMF) induces dramatic changes in bone. Bone remodeling and densitometric alterations in a series of nine patients with IMF and their relationship with the histologic stage of the disease were assessed. Patients were included at diagnosis and a bone marrow biopsy, dual-energy X-ray absorptiometry, and transiliac bone biopsy for histomorphometric analysis were performed. Five cases were classified as IMF histologic stage 1, one as stage 2, and three as stage 3. Compared with 40 age- and sex-matched controls, the following histomorphometric parameters were significantly higher in our patients: bone volume (BV/TV), osteoblast surface (Ob.S/BS), eroded surface (ES/BS), osteoclast surface (Oc.S/BS), osteoclast number (N.Oc/TA), mineralizing surface (MS/BS), reversal period (Rv.P), and remodeling period (Rm.P). Mineral apposition rate (MAR) and erosion depth (E.Depth) were significantly decreased (P < 0.05 for all comparisons). Bone mineral density (BMD) measurements showed high values for patient age and sex both at femur neck (Z score range +0.19 to +7) and total femur (Z score range -0.09 to +6.48). When densitometric values were analyzed according to IMF histologic stage, patients in stages 1 and 2 had significantly lower BMD values than to those in stage 3 (P = 0.024). In conclusion, patients with IMF present a characteristic bone histomorphometric pattern with increased bone volume and bone cells but low apposition and decreased erosion depth, suggesting a positive balance in bone remodeling units. This balance would produce the increase in bone mass observed in this disease. Given the increase in BMD observed with more advanced stages of IMF, this noninvasive method could be useful tool for assessing IMF progression.

Alendronate and etidronate do not regulate interleukin 6 and 11 synthesis in normal human osteoblasts in culture

Bisphosphonates exert a potent inhibitory effect on bone resorption. Several studies have been performed, with contradictory results, to ascertain whether the effect of bisphosphonates on osteoclasts could be produced, at least in part, by modulation of the synthesis of resorption-promoting factors by osteoblasts. The aim of this study was to evaluate the effect of etidronate (10-4-10-9 M) and alendronate (10-7-10-12 M) on the production of IL-6 and IL-11 using human osteoblast cultures. Cytokines were quantified by ELISA, and mRNA expression was tested. Treatment with alendronate and etidronate had no effect on the synthesis of IL-6 or IL-11, and IL-6 and IL-11 mRNA levels. These results were obtained both in nonstimulated cultures and in cultures stimulated by means of TNF-a, IL-1b, and TNF-a+IL-1b, with or without FCS. In conclusion, a possible indirect osteoclast-mediated effect of alendronate and etidronate on bone resorption would not be exerted through reduction in osteoblastic synthesis of IL-6 and IL-11.

Host cell-derived cardiomyocytes in sex-mismatch cardiac allografts

BACKGROUND

Mesenchymal precursor cells are able to respond to tissue signals and differentiate into a phenotype characteristic of mature cells of that tissue. We sought to investigate whether adult human cardiomyocytes can be derived from recipient precursor cells in sex-mismatched cardiac allografts.

METHODS

We studied four male patients who received hearts from female donors, and four female patients who received an allograft from a male donor. Four sex-matched transplant patients, two of each sex served as controls. Combined fluorescence in situ hybridization with probes specific for X- and Y-chromosomes and immunohistochemistry with alpha-actin was used to identify cardiac muscle cells 4 and 12 months after transplantation. Slides were examined with a fluorescence microscope to detect the presence of male cells with one X and one Y signal in the nucleus, and female cells containing two X signals.

RESULTS

Mature cardiomyocytes from the host (1-2%) were found in five endomyocardial biopsy specimens at 4 months, and in three specimens at 12 months. In addition, recipient cells negative for cytoplasmic alpha-actin were also identified (1-21% per slide). The number of infiltrating recipient cells was not associated with the degree of rejection of the sample or with the number of prior rejection episodes. Echocardiographic evaluation showed no improvement in cardiac performance in hearts from patients with more than 10% chimeric recipient cells.

CONCLUSIONS

Our data confirm the existence of mature cardiomyocytes derived from host cells, likely mesenchymal precursors, in the adult cardiac allograft in vivo.

Osteoblasts in HIV-infected patients: HIV-1 infection and cell function

BACKGROUND

HIV-infected patients have been shown to have a severe alteration in osteoblast function that appears to be related to the infection.

OBJECTIVE

To determine whether normal human osteoblasts express CD4, whether osteoblasts from patients with HIV infection are infected by HIV-1 and whether osteoblast dysfunction observed in vivo also occurs in vitro.

METHODS

Osteoblast cultures from bone marrow biopsies of HIV-infected patients (n = 14) and control patients (n = 10) were used in a cross-sectional study and a case-control prospective study. Expression of CD4 was analysed using flow cytometry and reverse transcriptase polymerase chain reaction; the presence of HIV-1 particles was determined by measuring p24 antigen in the supernatants of osteoblast cultures and viral DNA or RNA in the osteoblasts using the polymerase chain reaction. Osteoblast function was assessed by measuring cell proliferation, type I collagen and osteocalcin synthesis.

RESULTS

In human osteoblasts, CD4 expression could not be determined using flow cytometry, although low levels of mRNA coding for CD4 were detected. HIV infection was not observed in osteoblast cultures from HIV-infected patients nor was there any alteration in replication and synthesis of type I collagen, although osteocalcin synthesis was increased.

CONCLUSIONS

It is unlikely that HIV-1 infects human osteoblasts in vivo; therefore, the hypothesis that these cells could act as local HIV-1 reservoirs should be reconsidered.

Intercellular junctions, apical differentiation, and infiltrative features in colon cancer: an ultrastructural study. The Colon Cancer Team at IMAS

Changes in the structure and number of cell junctions have been related to the infiltrative and metastatic potential of tumor cells. Apparently, the loss of cell adhesion should be coordinated with significant changes in the apical and basal cell domains. The authors have performed a sequential ultrastructural study of cells in the superficial, middle, and deep regions of well- and moderately differentiated colon adenocarcinomas. This was to investigate the differences in the organization of different membrane domains among tumor cells in the in situ areas, the advancing, infiltrative edge of the tumors, and the infiltrating zones between these two extreme zones. The results of the study suggest that the organization of these domains is not strictly coordinated, and that, for each infiltration level, both a settling and an infiltrating cell population can be found. These findings could explain the fact that apparently well-differentiated tumors are able to seed distant tissues with individual cells, rather than with well-differentiated glandular aggregates that would hardly be able to reach the vessel lumina without significantly modifying their organization.

DNA image cytometry. An alternative method in osteoblast proliferation assays

OBJECTIVE

To assess whether DNA image cytometry can be used as an alternative method to tritiated thymidine uptake quantification in osteoblast proliferation assays. STUD DESIGN: Proliferation of normal human osteoblasts incubated with normal human serum at 0%, 2.5%, 5%, 10%, 20% and 40% was quantified by tritiated thymidine uptake quantification and DNA image cytometry.

RESULTS

Tritiated thymidine uptake quantification showed that normal human serum stimulated the proliferation of normal human osteoblasts and that the degree of stimulation was directly related to the concentration of serum in the culture medium. Similar results were obtained when the DNA image cytometry assay was used. A highly significant linear relationship between the ranks of both methods was found (Spearman's r = 1.00, P = .0253).

CONCLUSION

DNA image cytometry may be a valuable alternative when the use of radioactive material is not desired and/or subsequent morphologic or immunocytochemical characterization of cells under study is required.

Nuclear beta-catenin in colorectal tumors: to freeze or not to freeze? Colon Cancer Team at IMAS

beta-Catenin mediates the interaction of E-cadherin with alpha-catenin and the actin cytoskeleton. Recent evidence indicates that when the tumor suppressor gene APC is inactivated, beta-catenin can translocate to the nucleus, where it acts as a transcriptional regulator. Because APC is inactivated in most colorectal cancers, beta-catenin nuclear localization would be expected in these tumors. In a study of adhesion molecule expression in frozen colorectal cancer tissues, we were surprised by failure to detect nuclear beta-catenin. Here we compared the reactivity of an anti-beta-catenin monoclonal antibody with 11 colorectal cancers using immunohistochemistry on sections of frozen or paraffin-embedded samples. beta-Catenin was never detected in the nuclei of normal or tumor cells in frozen tissue sections. By contrast, in 8/11 cases it was detected in the nuclei of tumor cells but not of normal cells in paraffin-embedded tissue sections. These results were confirmed with an independent rabbit polyclonal anti-beta-catenin serum. We also examined beta-catenin distribution in SW480 colon cancer cells, in which its nuclear accumulation has been reported. As in tissues, nuclear beta-catenin was detected in paraffin-embedded but not in frozen samples. These findings are relevant because of the increasing interest in the study of beta-catenin in tumors, based on its dual role in cell adhesion and transcriptional regulation.

In vitro synthesis of type I collagen: quantification of carboxyterminal propeptide of procollagen type I versus tritiated proline incorporation

Radioimmunoassay of the carboxyterminal propeptide of human type I procollagen has been recently introduced to measure in vitro synthesis of type I collagen by osteoblasts and fibroblasts. However, it has not been assessed whether the equivalent results are obtained with this new assay and with tritiated proline incorporation to collagen protein. To this purpose, both methods were used to quantify synthesis of type I collagen in normal human osteoblast cultures to which fetal calf serum and human serum were added in order to stimulate protein synthesis. A positive correlation in the results obtained by both methods was obtained (r = 0.95, P = 0.0001). Given the technical advantages of detection of levels to carboxyterminal propeptide of type I procollagen, we consider that this is the technique of choice for the quantification of in vitro synthesis of type I collagen by normal human osteoblasts.

Effect of alendronate on cultured normal human osteoblasts

Alendronate is an aminobisphosphonate with a potent anti-reabsorptive action that does not appear to interfere with bone mineralization, and is even able to increase bone mineral density in osteoporotic postmenopausal women through a still not fully understood mechanism. This study was conducted to assess the direct effect of alendronate on diverse aspects of normal human osteoblast physiology. For that purpose, the in vitro effect of a wide range of concentrations [from 10(-1) to 10(-12) mol/L] of alendronate on cell viability, proliferation, collagen synthesis, and the mineral-depositing capacity of normal human osteoblasts was tested. Alendronate effects were examined at 48 and 96 h of culture in the presence or absence of fetal calf serum. In vitro alendronate affected osteoblast viability at concentrations equal to or higher than 10(-4) mol/L. At concentrations equal to or higher than 10(-3) mol/L, no viable cells were observed in cultures. In vitro alendronate at concentrations between 10(-5) and 10(-12) mol/L did not have any effect on the proliferative capacity of normal human osteoblasts determined by two different techniques: (1) tritiated thymidine incorporation to DNA and (2) cell counting. Collagen synthesis by normal human osteoblasts showed a tendency to decrease following incubation with alendronate supplemented with fetal calf serum. This decrease was only statistically significant after 96 h of culture; however, a dose-response effect could not be documented. Finally, no effect of alendronate was observed on calcium deposition in vitro by normal human osteoblasts at concentrations equal to or lower than 10(-5) mol/L. In conclusion, the present study shows that alendronate in vitro does not affect viability, proliferation, and mineral deposit capacity of normal human osteoblasts at the concentration at which it inhibits by 50% the resorptive capacity of osteoclasts that for this drug has been reported as 2 x 10(-9) mol/L.

Medullary carcinoma of the breast: an ultrastructural morphometric study of nine cases

Ultrastructural and morphometric features of 10 medullary carcinomas of the breast (MC) were investigated. Cases with a long follow-up were selected by applying stringent histologic criteria. All tumors had a homogeneous appearance by light microscopy. Under transmission electron microscopy, they showed occasional intracellular lumen formation or keratinization. In one tumor squamous differentiation was prominent and diffuse. Tumors with lymph node metastases possessed over 40% more desmosomes than nonmetastatic tumors. The number of cells with three or more nucleoli per nuclear section was significantly higher in metastatic than in nonmetastatic tumors (p = .02). Classic cases of MC of the breast display a relatively uniform appearance. However, subtle differences can be identified between metastatic and nonmetastatic tumors by ultrastructural morphometry. Although these differences are not associated with changes in the outcome of patients in this study, they seem to bear some relationship to the peculiar behavior of MC.

Osteoblastic proliferation in bone biopsies from patients with end-stage chronic renal failure

Osteoblasts have traditionally been considered to be terminally differentiated cells and therefore unable to divide. Data in recent years, however, indicate that cellular differentiation does not usually preclude preservation of proliferative ability and that most differentiated cells are able to divide under adequate stimuli. The aim of this study was to assess whether cubic osteoblasts undergo proliferation during the formation phase of the remodeling cycle under a stimulus that increased bone turnover. For that purpose, the osteoblastic proliferation index (OPI) was analyzed by DNA image cytometry in transiliac bone biopsies from 33 patients with chronic renal failure (23 men, 10 women; mean age 50.4 +/- 15.1 years) who have been classified into low (n = 13), normal (n = 15), and high (n = 15) bone turnover according to activation frequency (Ac.f). OPI was significantly higher (p < 0.002) in the high bone turnover group (13.90 +/- 4.72%) compared with the low (2.38 +/- 4.13%) and normal turnover groups (2.84 +/- 4.04%). There was a positive correlation between OPI and the following histomorphometric parameters: bone formation rate, surface referent (r = 0.76, p = 0.00001), activation frequency (r = 0.73, p = 0.00001), mineral apposition rate (r = 0.73, p = 0.00001), bone formation rate, volume referent (r = 0.71, p = 0.00001), and mineralizing surface (r = 0.62, p = 0.0001). This study shows that a rise in bone turnover is associated with a marked increase of bone-forming cell proliferation in patients with end-stage chronic renal failure. From this finding, it may be concluded that cubic osteoblasts do not behave as "terminally differentiated" cells in vivo, because a high proportion of them are still able to divide.

Bone remodeling alterations in myelodysplastic syndrome

There is a close relationship between hematopoietic bone marrow and bone cells. Thus, the profound derangement of hematopoiesis in myelodysplastic syndromes (MDS) might be expected to affect bone cell function. We studied the dynamic histomorphometric changes in bone in 22 MDS patients to examine this relationship and analyze the influence of hematological disease on bone remodeling. Bone-regulating hormones and histomorphometry of undecalcified transiliac bone biopsies, after double tetracycline labeling, were studied. Serum calcium, phosphorus, creatinine, alkaline phophatase, osteocalcin, iPTH, 25(OH)D3, 1,25(OH)2D3, hydroxyprolinuria, and calcium/creatinine ratio in urine were normal compared with controls. Histomorphometry showed a significant decrease in osteoblast surface (Ob.S/BS) (0.30 +/- 0.40 vs. 0.8 +/- 1.1, p = 0.031), wall thickness (W.Th), (22.03 +/- 5.5 vs. 31.8 +/- 5.8, p < 0.005), osteoclast number (N.Oc/T.Ar) (0.004 +/- 0.01 vs. 0.017 +/- 0.01, p = 0.03), mineral apposition rate (MAR) (0.16 +/- 0.15 vs. 0.53 +/- 0.19, p < 0.005), bone formation rate, surface referent (BFR/BS) (0.004 +/- 0.10 vs. 0.016 +/- 0.016, p = 0.009), and activation frequency (Ac.f) (0.06 +/- 0.07 vs. 0.21 +/- 0.23, p = 0.008). An increase in mineralization lag time (MLT) (119.2 +/- 78.6 vs. 29.6 +/- 77, p < 0.005), (mean +/- SD, unpaired Student t-test) was observed. Bone volume (BV/ TV), eroded surfaces (ES/BS), and osteoid thickness (O.Th) remained unchanged. This picture of adynamic bone with decreased mineral apposition rate and markedly decreased osteoclast number is a characteristic finding in MDS patients. Thus, bone histomorphometric finding in MDS patients show the relationships and interactions between hematopoietic and bone cells.

Increased radionuclide uptake on bone scintiscans: a common but not clinically significant finding for human immunodeficiency virus type 1-infected patients free of osteoarticular symptoms

The aim of this study was to describe findings of bone scintiscans and their clinical significance for patients infected with human immunodeficiency virus type 1 (HIV-1); 33 HIV-1-infected patients (22 men and 11 women) free of osteoarticular symptoms were included in the study. Plain bone roentgenograms, bone mineral contents (measured by dual-photon absorptiometry), and scintiscans (determined with 99mTc diphosphonate) were obtained for all subjects. Plain bone roentgenograms showed no abnormalities, and bone mineral contents were within the normal range for all patients. Radionuclide bone scans were unremarkable for eight patients (24%) and showed symmetrical abnormally increased uptake in the epiphyseal region of the appendicular skeleton in 25 (76%). Follow-up of the patients for > or = 1 year ruled out subsequent development of osteoarticular disorders. Generalized, symmetrical increased radionuclide uptake on bone scans is a common finding for HIV-1 infected patients free of osteoarticular symptoms. This finding is probably related to bone marrow hypercellularity and is of no clinical significance; therefore, other diagnostic procedures are not required in the workup of these patients.

Bone growth and modeling changes induced by periosteal stripping in the rat

In this study, the changes in longitudinal bone growth and metaphyseal modeling induced by middiaphyseal periosteal stripping in the rat femur were analyzed by means of histomorphometrical techniques. One hundred forty-four male 30-day-old Sprague-Dawley albino rats distributed in 4 groups of 36 were studied: a control group, a sham group, a group with middiaphyseal right femoral periosteal stripping, and a group with a polyethylene ring wrapped around the stripped zone. The animals were euthanized at 1, 2, or 4 weeks from the start of the experiment, after double tetracycline labeling. A statistically significant, albeit small, longitudinal overgrowth of stripped femurs was observed after a latency period of 2 to 4 weeks. The metaphyseal diameters were greater in stripped femurs than nonstripped femurs. This finding was associated with a lower osteoclastic index in the external metaphyseal surface and with a lower bone formation rate in the internal surface of the metaphyseal cortex. These latter findings have not been reported previously in the literature and may support the role of the periosteum in controlling metaphyseal modeling.

Bone remodelling in human immunodeficiency virus-1-infected patients. A histomorphometric study

The aim of this study was to identify and describe possible alterations of bone histomorphometry in patients with human immunodeficiency virus (HIV-1) infection and to assess the relation between these alterations and disease severity. Forty-four HIV-1-infected patients seen successively at our hospital were evaluated for the study. In an attempt to avoid confounding factors as far as possible, we excluded patients who fulfilled any of the following criteria: age less than 18 or greater than 40 years; recent history of extended bed rest; previous diagnosis of metabolic bone disease, renal insufficiency, or hepatic failure; clinical or echographic signs of liver cirrhosis; diabetes mellitus or previous diagnosis of other endocrine diseases; drug therapy that could act on bone metabolism; and/or moderate to severe nutritional alteration. Twenty-two patients (13 men, 9 women; age: 27.9 +/- 4.1 years, mean +/- standard deviation) were included in the study. Plasma and urine biochemistry and calcium-regulating hormones were determined. Bone mineral content was measured on vertebrae L2 to L4 and on the neck and intertrochanteric areas of the femur by dual-photon absorptiometry. A transiliac bone biopsy was performed after double-tetracycline labelling, with histomorphometric study of undecalcified bone. Serum osteocalcin was found to be lower in patients who, according to the Centers for Disease Control (CDC) classification, had greater disease severity, and showed a positive correlation with the number of CD4+ T lymphocytes. No alterations in bone densitometry were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of cyclosporine A on normal human osteoblasts in vitro

Cyclosporin-A (CsA) inhibits in vitro proliferation of non-human tumour-cloned osteoblasts. Our aims were to study the direct effect of CsA on proliferation of normal human osteoblast (NHOb) cultures and to ascertain whether CsA-treated patients' sera (CsATPS) may exert effects on the osteoblast which differ from the direct effects of CsA. We studied tritiated thymidine ([3H]thymidine) incorporation in NHOb cultures incubated with (a) increasing CsA concentrations (1.2 to 4800 ng/ml), (b) the same concentrations as in the previous experiment but with the addition of 20% fetal calf serum (FCS) or 20% normal human serum (NHS), (c) 40% NHS or 40% CsATPS. Results at 96 h in (a) CsA inhibited uptake from 300 ng/ml, in (b) CsA inhibited [3H]thymidine uptake from 2400 ng/ml for cultures with FCS and 4800 ng/ml for cultures with NHS, in (c) CsATPS produced [3H]thymidine uptake inhibition compared with NHS.

CONCLUSION

CsA alone inhibited [3H]thymidine incorporation in NHOb from concentrations similar to therapeutic concentrations. With FCS or NHS, inhibition was produced at higher concentrations. CsATPS inhibited at CsA concentrations lower than those of the two previous experiments.

Alcohol-induced bone disease in the absence of severe chronic liver damage

To define and identify metabolic bone disease and mineral alterations induced by chronic heavy alcoholism in patients without severe liver damage, we studied a prospective series of unselected patients admitted to a 300-bed general hospital in Barcelona (Spain). A total of 26 chronic heavy drinkers of more than 150 g/day for at least 3 years were included. A general analytic and hormonal study, including liver biopsy in cases with any abnormality in liver function tests, and plasma and urine biochemistry with calcium regulating hormones and osteocalcin levels were determined. A transiliac bone biopsy after double-tetracycline labeling, with histomorphometric study of undecalcified bone, was performed. Statistical analysis was adjusted by age and sex by means of logistic regression. A total of 26 (20 men and 6 women) chronic alcohol abusers were studied. After adjustment for age and sex, alcoholic patients showed slight but significantly increased concentrations of plasma calcium (9.56 +/- 0.56; OR = 17.93; 95% CI 3.17-101.48) and decreased cPTH (0.36 +/- 0.11; OR = 0.097; 95% CI 0.018-0.528) compared with controls. Osteocalcin values were low (1.49 +/- 0.89, normal range 1.8-6.6). There was a significant decrease in bone volume, BV/TV (12.56 +/- 5.29; OR = 0.06; 95% CI 0.01-0.34), with increased resorption surfaces, ES/BS (4.28 +/- 2.43; OR = 9.86; 95% CI 2.16-45.07), and increased osteoclast number, N.Oc/TA (0.21 +/- 0.37; OR = 6.41; 95% CI 1.27-32.25).(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation between densitometric and hystomorphometric values in isolated vertebrae of Sprague-Dawley rats

The study of bone mass in experimental animals usually requires invasive techniques. Dual energy X-ray absorptiometry (DEXA) may be an alternative as a non-invasive method (1). Bone mineral density (BMD) and bone mineral content (BMC) of 62 vertebrae of Sprague Dawley rats (SDr) measured by DEXA densitometry were compared with histomorphometric bone volume measurements, and a statistically significant correlation was found (r = 0.79 and 0.75, respectively, p < 0.001). In conclusion, DEXA is an accurate and feasible technique for the study of trabecular bone mass in SDr.