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INTRODUCTION: Ligamentous lesions are concomitant to dislocated distal radius fractures in a high percentage. The purpose of this study was to evaluate the relevance of intracarpal lesions. METHODS: Seventy eight of an original cohort of 104 distal radius fractures (74%) were studied over a follow-up period of one year after surgery with complete data (X-rays, CT, MRI, follow-up X-rays and questionnaire). RESULTS: Most of our radius fractures (AO 23 type: A 39, B 9, C 30) present additional lesions: 97%. One-year evaluation showed an average Castaing score of 4.5 ± 2.5 points, means a "good" result of a scale of 0-27. Fifty five of seventy eight had an "excellent" or "good" result (<6 points). No patient had more than 12 points ("fair"). CONCLUSIONS: The dislocated distal radial fracture implies severe and complex injury to the whole wrist, mostly concerning intracarpal concomitant lesions (MRI). Surgical therapy of dislocated radius fractures followed by 6 weeks relief through thermoplastic splint seems to be sufficient to achieve good 1-year results. MRI-detectable carpal lesions at the time of the radial fracture are common, but only a few of them seem to decompensate later, give symptoms and became of therapeutic relevance.

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In addition to its primary role as growth factor, human growth hormone (hGH) can also participate in cell survival, as already documented by its protective effect on human monocytes or human promyelocytic leukaemia U937 cells exposed to a Fas-mediated cell death signal. However, despite similarities in the molecular events following Fas and TNF-alpha receptor engagement, we report that U937 cells, genetically engineered to constitutively produce hGH, were made more sensitive to TNF-alpha-induced apoptosis than parental cells. This was due to overproduction of the antioxidant glutathione, which decreased the nuclear factor (NF)-kappaB activity known to control the expression of survival genes. These findings were confirmed in vivo, in nude mice bearing U937 tumours coinjected with recombinant hGH and the NF-kappaB -inducing anticancer drug daunorubicin, to avoid the in vivo toxicity of TNF-alpha. This study therefore highlights one of the various properties of hGH that may have potential clinical implications.

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Chemotherapy remains the main tool for the treatment of cancers, but is often hampered by tumor cell resistance. In this context, the transfer of genes able to accentuate the effect of anticancer drugs may constitute a useful approach, as exemplified by inactivation of nuclear factor (NF)-kappa B via direct transfer of a gene encoding a negative dominant of its natural inhibitor I kappa B, leading to improved response to cancer chemotherapy. Following our previous report that transfection of human growth hormone (hGH) gene into human monocytic cell lines may also inactivate NF-kappa B in another situation, we decided to test the consequences of hGH gene transfer on cancer treatments. We demonstrated that hGH-transfected human myeloid leukemia U937 cells were sensitized to an apoptotic signal mediated by the anticancer drugs. In parallel, we found that, by inhibiting degradation of I kappa B, hGH gene transfer diminished NF-kappa B entry into the nuclei of U937 cells exposed to daunorubicin. Finally, we report that hGH-transfected tumor cells engrafted in nude mice responded in vivo to chemotherapy with nontoxic doses of daunorubicin whereas, under the same conditions, control tumor cells remained insensitive. Overall, this study therefore suggests that hGH gene transfer may offer new therapeutic prospects in cancer therapy.

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Large areas of sub-Saharan Africa suffer a substantial lack of skin care. Hence teledermatology, meaning the online visual exchange of clinical and histologic data, could develop into a powerful medical resource. We report the first established teledermatologic connection in this area: between the Regional Dermatology Training Centre (RDTC) in Moshi, Northern Tanzania, and the Department of Dermatology, University Hospital of Zürich, Switzerland. This report illustrates local difficulties as well as the considerable potential of teledermatology in such a setting.

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Apoptosis and particularly Fas-mediated apoptosis has been proposed to play a key role in controlling monocyte homeostasis. We and others have documented the regulatory function of human growth hormone (hGH) on monocytic cells, which prompted us to investigate the role of hGH on their response to Fas antigen cross-linking. Using human promonocytic U937 cells constitutively producing hGH upon gene transfer and human primary monocytes cultured in the presence of recombinant hGH, we demonstrated that hGH diminished Fas-mediated cell death by enhancing the expression of the antiapoptotic oncoprotein Bcl-2 as well as the level of bcl-2alpha mRNA. In parallel, we established that overexpression of Bcl-2 through gene transfer into normal U937 cells also diminished Fas-induced apoptosis. Further, as a result of Bcl-2 overexpression, we found that hGH greatly depressed Fas-induced activation of the cysteine protease caspase-3 (CPP32), which in turn affected the cleavage of poly(ADP-ribose) polymerase. Altogether, these data provide evidence that hGH mediates its protective effect through a Bcl-2-dependent pathway, clearly a crucial step in enhanced survival of monocytic cells exposed to Fas-induced death.

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The diagnosis of lymphoproliferative and melanocytic skin lesions is one of the most vexing problems in dermatopathology, a problem that is compounded by the far-reaching therapeutic and psychosocial consequences of the diagnosis for both patient and physician. On the occasion of a self-assessment slide seminar held during a dermatopathology meeting, 30 unusual lymphoproliferative and melanocytic lesions, each provided with four differential diagnoses, were evaluated by "expert pathologists" and other participants ("nonexperts") of the slide seminar. The final diagnosis was pinpointed by the majority of the experts in 16 of 30 cases (56%). The group of experts returned an unanimous decision on the diagnosis in only 2 of the 30 cases (7%). In contrast to the expert group, the preferred diagnoses given by the nonexperts showed a wider range. In 20 of 30 cases (66%), the final diagnosis could only be established after consideration of clinical, histologic, immunophenotypic, and molecular features. Our findings agree with the results of recent studies indicating quite a high degree of discordance among expert pathologists. The discordance between experts and, to a higher extent, nonexperts may have some crucial consequences for dermatopathology. Full agreement on diagnosis, particularly in unusual skin lesions, cannot be achieved only by an accumulation of expertises. Instead of relying on one single finding or diagnostic procedure ("gold standard") as the main criterion upon which to base a diagnosis, the diagnoses become more reliable if based on the integration of several factors including an evaluation of clinical and histomorphologic features and immunophenotypic and molecular findings ("diagnostic elements"), particularly in the field of lymphoproliferative and melanocytic lesions. In addition, a continuous retrospective work-up of difficult or unusual cases is recommended to ensure a long-term improvement in diagnostic reliability.

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Associations of human leukocyte antigens (HLA) with the idiopathic nephrotic syndrome (NS) have mainly been described for alleles of the HLA-DR locus. In the present study the polymorphism of HLA-DQ and -DP at the molecular level was investigated in 167 children with NS (129 steroid-sensitive) using the polymerase chain reaction and sequence-specific oligonucleotides in a French and a German cohort. HLA-DR typing was also performed by classical serology. In steroid-sensitive patients we observed an increased frequency of the alleles HLA-DQA1*0201 and -DQB1*0201 in both populations with relative risks ranging from 3.8 to 8.5 (Pb < 0.01 to Pb < 0.00001 after Bonferoni's correction). In contrast, the frequency of HLA-DQA1*0102 and DQB1*0602 was significantly decreased. In children with frequent relapses the HLA associations were generally more pronounced than in those with infrequent or no relapses. Applying logistic regression analysis, a nephrotic child bearing DQA1*0201 or DR7 was five times more likely to be in the steroid-sensitive group of patients than in the steroid-resistant group compared with nephrotic children not bearing one of these alleles. These HLA alleles therefore seem to be useful indicators of a steroid-sensitive frequently relapsing course of NS. No associations with DPB alleles were observed, which narrows the region genetically involved in the disease susceptibility to the DR-DQ region. Steroid-resistant NS was not associated with HLA.

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OBJECTIVE: To characterize tumor-infiltrating lymphocytes (TILs) within lesions of cutaneous squamous cell carcinoma (SCC) and related disorders. DESIGN: Case series with 1- and 2-color immunohistologic, molecular biological analysis of T-cell clonality and in vitro cytotoxicity assays. SETTING: Academic medical center. PATIENTS: Twenty-one patients, including 6 with actinic keratoses, 4 with SCC in situ, and 11 with invasive SCC. RESULTS: CD8+ TILs were present within lesions of cutaneous SCC and AK. These cells constituted a variable minority of the total T-cell infiltrate, and many expressed a phenotype consistent with major histocompatibility complex-restricted cytotoxic T lymphocytes: CD3+, TIA1+, CD16-, CD56-, CD57-. They also expressed HLA-DR, suggesting their activation in vivo. Virtually all T cells were T-cell receptor (TCR)-beta + delta, indicating that they expressed the TCR-alpha beta protein heterodimer. Molecular biological analysis of TCR-gamma gene rearrangements by the polymerase chain reaction and denaturing gradient gel electrophoresis technique indicated that the TILs were polyclonal. Functional studies suggested that TILs derived from SCC lesions were cytotoxic for autologous tumor cell targets. CONCLUSION: Tumor-infiltrating lymphocytes within cutaneous SCC lesions contain a subpopulation of polyclonal, major histocompatibility complex-restricted cytotoxic T lymphocytes expressing the TCR-alpha beta heterodimer.

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Several studies have pointed to a link between immune and endocrine systems, including a regulatory function of GH on monocyte activation. The present study demonstrates that human THP-1 promonocytic cells, engineered by gene transfer to constitutively produce human growth hormone (hGH), secreted depressed amounts of TNF-alpha in response to challenge by LPS. The effect of GH appears to occur in an autocrine fashion, since the inhibitory effect on TNF-alpha secretion by constitutive GH production could be abolished in the presence of anti-hGH mAb. The GH-induced inhibitory effect was also observed using normal human monocytes and monocyte-derived macrophages. Inhibition of TNF-alpha production by THP-1-hGH-transfected cells cultured in the presence of LPS is dependent on a selective pathway, since no inhibition of TNF-alpha production was observed when cells were cultured in the presence of PMA. Inhibition of TNF-alpha secretion by LPS-stimulated THP-1-hGH cells was associated with a decrease in nuclear translocation of nuclear factor-kappaB. The capacity of GH to inhibit LPS-induced TNF-alpha production by monocytes without altering other pathways leading to TNF-alpha production may be of potential relevance in septic shock, since GH is available for clinical use.

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In a number of experimental systems, the early stage of the apoptotic process, i.e., the stage that precedes nuclear disintegration, is characterized by the breakdown of the inner mitochondrial transmembrane potential (delta psi m). This delta psi m disruption is mediated by the opening of permeability transition (PT) pores and appears to be critical for the apoptotic cascade, since it is directly regulated by Bcl-2 and since mitochondria induced to undergo PT in vitro become capable of inducing nuclear chromatinolysis in a cell-free system of apoptosis. Here, we addressed the question of which apoptotic events are secondary to mitochondrial PT. We tested the effect of a specific inhibitor of PT, bongkrekic acid (BA), a ligand of the mitochondrial adenine nucleotide translocator, on a prototypic model of apoptosis glucocorticoid-induced thymocyte death. In addition to abolishing the apoptotic delta psi m disruption, BA prevents a number of phenomena linked to apoptosis: depletion of nonoxidized glutathione, generation of reactive oxygen species, translocation of NF kappa B, exposure of phosphatidylserine residues on the outer plasma membrane, cytoplasmic vacuolization, chromatin condensation, and oligonucleosomal DNA fragmentation. BA is also an efficient inhibitor of p53-dependent thymocyte apoptosis induced by DNA damage. These data suggest that a number of apoptotic phenomena are secondary to PT. In addition, we present data indicating that apoptotic delta psi m disruption is secondary to transcriptional events. These data connect the PT control point to the p53- and ICE/ Ced 3-regulated control points of apoptosis and place PT upstream of nuclear and plasma membrane features of PCD.

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Monocyte/macrophages may harbor HIV in a nonproductive fashion for prolonged periods of time. Viral gene expression may be reactivated by stimulation of the cells with LPS or cytokines such as TNF-alpha in vitro. The effect of LPS and TNF-alpha is mediated by their ability to induce nuclear translocation of the DNA-binding heterodimer NF-kappa B (p50/p65), which binds to a specific sequence in the HIV-long terminal repeat. The present study demonstrates that triggering of complement receptors CR1 (CD35) and CR3 (CD11b/CD18) enhances viral replication in HIV-infected human monocytic cells. Monocytic cell lines and normal peripheral blood monocytes were infected with HIV-1 in vitro and cultured in the presence or absence of F(ab')2 fragments of monoclonal anti-CR1 or anti-CR3 Abs or with C3 fragments. Stimulation of CR1 or CR3 induces a two- to fourfold increase in the amount of cell-associated and released p24 Ag in cell cultures that was equivalent to that observed in control cultures triggered with LPS. We further observed that stimulation of CR1 or CR3 induces the nuclear translocation of NF-kappa B p50/p65 in infected cells. Translocation of NF-kappa B p50/p65 was also observed following stimulation of CR1 or CR3 of uninfected peripheral blood monocytes from HIV-seronegative donors. The amount of protein translocated was similar to that observed when cells were stimulated with rhTNF-alpha. TNF-alpha did not mediate the translocation of NF-kappa B p50/p65 induced by triggering of complement receptors. Taken together, these observations suggest that HIV gene expression may be activated in infected monocytes through interaction of the cells with complement-opsonized particles and that enhanced viral replication is associated with C3 receptor-mediated nuclear translocation of the NF-kappa B complex.

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BACKGROUND: Small plaque parapsoriasis is an idiopathic chronic dermatosis characterized by patches on the trunk and extremities that are often smaller than 5 cm in diameter and that sometimes have a digitate contour. These latter cases are often referred to as digitate dermatosis. Histopathologic examination reveals a mild superficial perivascular lymphocytic infiltrate associated with mild spongiosis and parakeratosis. To characterize this disease more completely, we analyzed the differentiation and clonality of lesional lymphocytes using immunohistologic and molecular biologic methods. OBSERVATIONS: We studied five cases using a frozen-section immunoperoxidase technique. In each case, there was a predominantly CD4+ T-cell infiltrate admixed with CD8+ T cells, Langerhans cells/indeterminate cells, and macrophages. In three cases, the clonality of lesional T cells was studied by denaturing gradient gel electrophoresis of polymerase chain reaction-amplified T-cell receptor-gamma gene rearrangements. Two cases showed a dominant clonal pattern, while one case exhibited a polyclonal pattern. Clinical follow-up disclosed persistent disease in one of the two clonal cases, while lesions in the other clonal case and the polyclonal case gradually resolved. CONCLUSIONS: Our findings indicate that small plaque parapsoriasis is a clinically indolent, histopathologically nonspecific, predominantly CD4+ T-cell-mediated disease that, at least in some cases, contains a dominant T-cell clone. These features put small plaque parapsoriasis into a category with certain other members of the parapsoriasis group, namely, pityriasis lichenoides and lymphomatoid papulosis, which have been shown to be clonal T-cell disorders despite their clinically benign course. It remains to be determined if the dominant T-cell clones identified in some cases of small plaque parapsoriasis can ever be the direct precursors of overt cutaneous T-cell lymphomas.

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The bcl-2 protein prolongs cell life by inhibiting apoptosis. Its expression has been studied in a variety of normal tissues and lymphomas but there is minimal information available concerning bcl-2 expression by benign and malignant cutaneous T-cells. Therefore, we investigated bcl-2 expression in a wide variety of cutaneous T-cell infiltrates using one- and two-color immunohistologic techniques. bcl-2 was expressed by the majority of lesional CD3+ T-cells in most cases. This included 22/26 cases of mycosis fungoides (MF), 3/3 cases of non-MF cutaneous T-cell lymphoma, 5/5 cases of lymphomatoid papulosis, 4/4 cases of T-cell rich cutaneous lymphoid hyperplasia, 2/3 cases of bullous pemphigoid, 2/2 cases of discoid lupus erythematosus and 1/1 case of lichen planus. Titration experiments and comparative studies of tonsil section positive controls revealed that, relative to mantle zone B-cells, there was over- expression of bcl-2 by a variable subset of T-cells in most cases. Assessment of multiple biopsies in a subset of MF cases showed stable expression of bcl-2 over intervals of up to two years. In contrast to the widespread expression of bcl-2 in both early and advanced MF skin lesions, abundant expression of the nuclear proliferation antigen, Ki-67, was skewed toward advanced MF skin lesions. Ten percent or more Ki-67+ cells were present in 5% of patients with patches/thin plaques, 38% with moderate plaques, 64% with thick plaques and 100% with tumor nodules.(ABSTRACT TRUNCATED AT 250 WORDS)

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We used a gene amplification strategy to analyze T-cell receptor (TCR) gene rearrangements in 185 specimens, including mycosis fungoides/Sezary syndrome (MF/SS), other cutaneous neoplasms, inflammatory dermatoses, reactive lymphoid tissues, and normal skin. Genomic DNA was extracted from lesional tissues and rearrangements of the TCR-gamma chain gene were amplified using the polymerase chain reaction (PCR) with primers specific for rearrangements involving V gamma 1-8 or V gamma 9 gene segments. The resulting PCR products were then separated according to their nucleotide sequence as well as size by denaturing gradient gel electrophoresis (DGGE). Dominant clonal TCR-gamma gene rearrangements were detected in 61 of 68 MF/SS cases by PCR/DGGE. This sensitivity of 90% compared to a sensitivity of only 59% when dominant clonality was sought in 17 of these same cases by Southern blot analysis of TCR-beta gene rearrangements. This difference in sensitivity was greatest in early, minimally infiltrated skin lesions. PCR/DGGE was also more sensitive than Southern blot analysis for detecting peripheral blood involvement in two cases of early MF. Among 12 additional specimens of suspected MF/SS, nine (75%) showed clonal TCR-gamma gene rearrangements by PCR/DGGE including six of eight cases with a previously confirmed diagnosis of MF/SS and three of four cases without prior known MF/SS. Among 105 non-MF/SS specimens, dominant TCR-gamma gene rearrangements were detected in only six cases (6%). Four were diagnosed as chronic dermatitis and two were diagnosed as cutaneous lymphoid hyperplasia. We conclude that the large majority of MF/SS cases, including patch phase disease, possess dominant clonal TCR-gamma gene rearrangements. PCR/DGGE is more sensitive than Southern blot analysis for detecting dominant clonality and staging disease in patients with a confirmed diagnosis of MF/SS. However, because PCR/DGGE is sensitive enough to detect dominant TCR-gamma gene rearrangements in a subset of patients with chronic dermatitis, it cannot be used as the sole criterion for establishing a diagnosis of T-cell lymphoma. As with other molecular biologic clonality assays, clinicopathologic correlation is essential. Nevertheless, the detection of dominant clonality in some cases of histologically nonspecific dermatitis allows the identification of a previously unrecognized subset of patients, i.e., those with "clonal dermatitis." It will be important to determine the long-term risk of MF/SS among these patients because our study indicated that MF/SS can sometimes present with lesions indistinguishable from clonal dermatitis.

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The molecular biologic analysis of TCR gene rearrangements by Southern blot analysis and various PCR-based assays has contributed significantly to the understanding of CTCL. It is now known that CTCL is a monoclonal T-cell disorder like other T-cell neoplasms and that the same tumor clone is generally present in all sites of tissue involvement. Relative to histopathologic examination, the enhanced sensitivity of molecular biologic assays has allowed the diagnosis of CTCL at an early stage in many cases. In fact, molecular biologic analysis of TCR gene rearrangements suggests that CTCL may contain a dominant monoclonal tumor cell population from the time of its earliest clinically recognizable lesions, such as the cutaneous patches once termed large plaque parapsoriasis and now generally regarded as early CTCL. Furthermore, available data indicate that, at least in some cases, tumor cells are distributed widely among cutaneous and extracutaneous tissues at a time long before this involvement can be appreciated morphologically. It is apparent that, in addition to their value in the early diagnosis and staging of cutaneous lymphomas, these molecular biologic assays are valuable in monitoring the response to therapy, detecting early relapse, and improving understanding of the compartmentalization and trafficking of tumor cells. In order to reap the full clinical benefit from this new information, however, it is important to perform prospective long-term studies designed to determine the clinical significance of molecular biologic data. In addition, the complexity of cutaneous lymphoproliferative disorders dictates that molecular biologic clonality data should never be interpreted in a vacuum. In skin disease, dominant clonality does not always equate with clinical malignancy. The proper diagnosis of CTCL and other cutaneous lymphoproliferative diseases requires the thoughtful integration of molecular biologic data with the clinicopathologic and immunophenotypic findings.

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