Bcl-6 protein expression by follicle center lymphomas. A marker for differentiating follicle center lymphomas from other low-grade lymphoproliferative disorders.

Low-grade lymphoproliferative disorders are a heterogeneous group of lymphoid neoplasms with wide variation in histologic features, immunologic phenotype, and molecular abnormalities. Subclassification of these disorders with small lymphocytic proliferation may be difficult on the basis of morphologic findings alone. The bcl-6 gene, originally cloned from a tumor with 3q27 translocation, is commonly expressed in large cell lymphomas. In humans, bcl-6 encodes for a Krüppel-type zinc finger protein and is believed to be important in germinal center formation. Bcl-6 protein is expressed mainly by follicle center cells and a few interfollicular T lymphocytes. We analyzed Bcl-6 expression with immunologic methods in common low-grade lymphoproliferative disorders as an aid to differentiation of tumors with follicle center origin. We analyzed Bcl-6 staining of formalin-fixed paraffin-embedded tissue from 72 indolent lymphomas including 31 grade I and II follicle center lymphomas (FCL). 13 small lymphocytic lymphomas (SLL), 12 mantle cell lymphomas (MCL), and 16 marginal zone lymphomas (MZL) including lymphomas of mucosa-associated lymphoid tissue and spleen. All of 31 FCL were positive for Bcl-6 expression. One of 13 SLL and 1 of 12 MCL were positive, whereas none of 16 MZL were positive. Bcl-6 was also detected in 5 of 5 FCL and 1 of 3 MZL but in no SLL or MCL by Western blot analysis in 14 cases with lymphoid disorders. Our study demonstrates that Bcl-6 expression is common in low-grade FCL but is rare in other indolent B-cell lymphoid disorders, and may be a useful adjunct in classification of indolent lymphomas.

Theoretical analysis of dynamic force spectroscopy experiments on ligand-receptor complexes.

The forced rupture of single chemical bonds in biomolecular compounds (e.g. ligand-receptor systems) as observed in dynamic force spectroscopy experiments is addressed. Under the assumption that the probability of bond rupture depends only on the instantaneously acting force, a data collapse onto a single master curve is predicted. For rupture data obtained experimentally by dynamic AFM force spectroscopy of a ligand-receptor bond between a DNA and a regulatory protein we do not find such a collapse. We conclude that the above mentioned, generally accepted assumption is not satisfied and we discuss possible explanations.

Disseminated herpes simplex virus infection presenting as fever in the newborn--a lethal outcome.

The clinical course of a neonate who presented with fever and tachypnea on day 6 of life is described. He developed disseminated intravascular coagulopathy, hepatic failure, coma and expired at 14 days of age. The post mortem viral cultures from liver, adrenal and lungs were positive for HSV type 2. The fatal outcome of this case of fever, due to HSV infection, emphasizes the need for early treatment of suspicious cases of HSV infection. HSV should be considered in the differential diagnosis of the newborn with persistent fever unresponsive to antibiotics.

Amorphous thin film growth: effects of density inhomogeneities.

A nonlinear stochastic growth equation for the spatiotemporal evolution of the surface morphology of amorphous thin films in the presence of potential density variations is derived from the relevant physical symmetries and compared to recent experimental results. Numerical simulations of the growth equation exhibit a saturation of the surface morphology for large film thickness originating from the inclusion of the density inhomogeneities. Furthermore, we argue why moundlike surface structures observed on vapor deposited amorphous films are not the result of the Grinfeld instability.

Malignant pleural effusion in Hodgkin's lymphoma. Report of a case with immunoperoxidase studies.

The cytologic and histopathologic findings in a patient with Hodgkin's lymphoma, mixed cellularity type, and a malignant pleural effusion are presented. The consistency of staining with a battery of immunoperoxidase monoclonal antibody stains, including leukocyte common antigen, Leu-M1, UCHL1 and L26, was examined on sections of formalin-fixed lymph nodes and alcohol-fixed pleural fluid cell blocks. In addition, these same tissues were stained with carcinoembryonic antigen, B72.3, cytokeratin and epithelial membrane antigen immunoperoxidase antibodies to differentiate the tumor cells from reactive mesothelial cells and adenocarcinoma cells. The results on the pleural fluid specimens were consistent with what is known of the immunohistochemical staining properties of Hodgkin's lymphoma cells in lymph nodes.

[Load stability in relation to the osteosynthesis method, course and complications in open lower-leg fractures with severe soft tissue lesions ]. / Belastungsstabilität in Abhängigkeit von Osteosyntheseverfahren, Verlauf und Komplikationen bei offenen Unterschenkelfrakturen mit schwerem Weichteilschaden.

The external fixator ("fixateur externe") is today's method of choice in the treatment of lower leg fractures with severe damage to the soft parts. The various application techniques and angles of application of this device entail varying stability and are characterized by certain advantages and drawbacks. Basing on detailed biomechanical studies and experience with patients, the authors prefer the rectangular mode of application using Schanz screws. If the type of fracture allows, a combination of minimal osteosynthesis and external tensor is used; this can significantly enhance the stability. In 42 patients of a total of 56 during 1978-1980 with second-grade and third-grade open fractures of lower leg, combination with minimal osteosynthesis was effected (traction screw). Of 44 patients followed up, 19 achieved stability to load within an average period of 19.8 weeks. If there is no osseous bridging 10-12 weeks after initial treatment, additional measures such as spongiosaplasty and changeover to stable inner fixation with plates become necessary. Following plate osteosynthesis with additional spongiosaplasty, full load was permissible on the average 14 weeks after this procedure in 23 patients. The course was more complicated in the case of the 2 remaining patients; it took up to 45 weeks until full load became permissible.

[Mobile and digital documentation of inpatient treatments : use of personal digital assistants in addition with the ClinicCoach(c) software]. / Mobile und digitale Behandlungsdokumentation im Krankenhaus : Einsatz von "personal digital assistants" in Verbindung mit der ClinicCoach(c)-Software.

BACKGROUND: Documentation of the individual treatment course is essential from medical as well as economic and forensic aspects. With increasing hospital computerization the conventional hardcopy form of record keeping is seen to be associated with high outlays and restrictiveness. METHODS: Clinicians engaged consistently in the development of a personal digital assistant (PDA)-based electronic record system (Clinic Coach(c)), which maps the entire course of inpatient treatments. The system's effectiveness was reviewed by means of a standardized questionnaire and analysis of 8,595 data sets relating to PPR and wound findings. RESULTS: In patients undergoing surgery wound findings and PPR were documented in 83.6% and in 94.3% respectively. The ClinicCoach(c) System was rated more effective than paper-based documentation by 78.4% of the testing healthcare workers. CONCLUSION: The combination of PDAs and ClinicCoach(c) is a reliable and to clinical routine well adapted system that allows digital documentation at the bedside.

Theoretical analysis of single-molecule force spectroscopy experiments: heterogeneity of chemical bonds.

We show that the standard theoretical framework in single-molecule force spectroscopy has to be extended to consistently describe the experimental findings. The basic amendment is to take into account heterogeneity of the chemical bonds via random variations of the force-dependent dissociation rates. This results in a very good agreement between theory and rupture data from several different experiments.

Pathophysiology and treatment of endometriosis.

The pathophysiology of endometriosis and its treatment are discussed. Endometriosis is a gynecological disorder characterized by the growth of the ectopic endometrium. The usual plaque looks like a small blood-filled cyst that is surrounded by a puckering scar. This tissue responds to fluctuating levels of hormones just as the normal endometrium does, and monthly bleeding of the cysts occurs followed by inflammation and scarring. Endometriosis may cause infertility, dyspareunia, dysmenorrhea, pelvic pain, and other menstrual problems. Therapy is chosen based on extent of disease, tolerance of side effects, and desire for pregnancy. Surgery is usually reserved for more extensive cases of the disease or if fertility is no longer desired. Induction of "pseudopregnancy" with estrogen-progesterone combinations has been used frequently; however, weight gain, initial exacerbation of pain, and the possibility of thromboembolism are limiting factors. Pseudomenopause, induced by danazol therapy, is an alternate method of treatment that causes a static endometrium. It offers rapid relief of symptoms to the majority of patients, and its most common side effects of weight gain and edema are reversible. Fertility rates after treatment are difficult to compare, but they appear to be similar for both hormonal therapies. Danazol has emerged as an effective alternative to the estrogen-progesterone combination treatment of endometriosis. Danazol may be prescribed before surgery to reduce lesions, following surgery to ablate any remaining lesions, or as the sole therapy for endometriosis.

Hematologic complications of heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is arguably the most significant of the drug-induced thrombocytopenias. Two main types of HIT, types I and II, are usually discussed. Type I HIT is characterized by a moderate reduction in platelet counts early in heparin therapy, usually within the first 1 to 3 days. The platelet count rarely drops below 100x10(9)/L and normalizes in spite of continued heparin therapy. Type II HIT is immunologically mediated. The definition of Type II HIT varies, but most studies require a platelet count below 100-150x 10(9)/L for no apparent reason other than heparin administration. Many patients with type II HIT suffer no morbidity. Unfortunately, a significant number, 30 to 60% or more, do develop serious thrombotic complications resulting in morbidity or mortality, including ischemic damage to limbs, central nervous system, myocardium, and lungs. Although earlier literature indicated that arterial thromboses occurred more frequently than venous, recent reports have found that venous thromboses, including deep venous thromboses, pulmonary emboli, and clotted venous catheters, have been common occurrences. In some studies, venous complications were more frequent than arterial. Most investigators have come to believe that these antibodies are largely directed against complexes formed between heparin and the tetrameric PF4. Recent studies devoted to exploring the mechanism by which these antibodies induce platelet activation and thrombosis are discussed.

[Fractures of the cervical spine]. / Verletzungen der Halswirbelsäule.

A gentle traction is often sufficient to repose unstable lesions of the cervical spine, when a retention by means of conservative methods is not possible. Therefore a ventral, intracorporal fusion with autologous, corticospongious chip material combined with a plate fixation is an adequate solution to obtain a stable, movable blocking of the lower six cervical vertebrae. In case of a completely ruptured dorsal ligamentous apparatus, a ventral bone-chip blocking is generally insufficient. Ventral spondylodesis should be combined with a dorsal traction belt in these cases. Fresh, instable fractures of the odontoid process can be stabilized for exercise by means of two traction screws fastened from the front side. However, the best method to treat a pseudarthrosis of the odontoid process is a fusion performed from the dorsal side.

Amorphous thin film growth: minimal deposition equation

A nonlinear stochastic growth equation is derived from (i) the symmetry principles relevant for the growth of vapor deposited amorphous films, (ii) no excess velocity, and (iii) a low-order expansion in the gradients of the surface profile. A growth instability in the equation is attributed to the deflection of the initially perpendicular incident particles due to attractive forces between the surface atoms and the incident particles. The stationary solutions of the deterministic limit of the equation and their stability are analyzed. The growth of the surface roughness and the correlation length of the moundlike surface structure arising from the stochastic growth equation is investigated.

Treatment by external fixation of open fractures associated with severe soft tissue damage of the leg. Biomechanical principles and clinical experience.

External fixation is the treatment of choice for fractures of the leg involving severe damage to the soft tissue. Each of the various patterns of application has advantages and disadvantages. Based on various biomechanical studies and clinical experience, the authors use a right-angle arrangement for the screws. If the type of fracture permits, internal and external fixation may significantly increase stability. During the period from 1978 to 1980, 56 patients with second- and third-degree open fractures were treated. A combination of external and internal fixation was used in 42 patients. Of the 44 patients re-evaluated at follow-up examinations, 19 had returned to unrestricted weight-bearing within 19.8 weeks. If no signs of bony union are noted ten to 12 weeks after the initial operation, cancellous bone grafting and internal fixation instead of external fixation are indicated. Twenty-three patients were fully weight-bearing an average of 14 weeks after internal fixation and cancellous bone grafting. Two patients had difficult problems and did not return to full weight-bearing until about 45 weeks after operation.

Uveal metastatic carcinoma in human immunodeficiency virus infection.

We report the occurrence of uveal metastatic carcinoma in two patients with longstanding HIV infection presenting with decreased visual acuity. In the first case, a 49-year-old man with a 6-year history of HIV infection presented with a 4-5 month history of blurred vision in his right eye. In the second case, a 53-year-old man with a 5-year history of HIV infection presented with a 3-week history of distorted and blurred vision in both eyes. In both cases, a choroidal metastatic carcinoma was ultimately discovered. To our knowledge, these are the first reported cases of metastatic uveal carcinoma in individuals with HIV infection. Currently, there have been dramatic improvements in treatment for HIV infection and longer survival times of infected individuals. This fact, together with reported increased frequencies and aggressiveness of carcinomas in HIV-infected individuals will likely result in increasing occurrences of uveal metastases from primary carcinomas in HIV.

Limits for the central production of Theta+ and Xi(--)pentaquarks in 920-GeV pA collisions.

We have searched for Theta+(1540) and Xi(--)(1862) pentaquark candidates in proton-induced reactions on C, Ti, and W targets at midrapidity and square root of s = 41.6 GeV. In 2 x 10(8) inelastic events we find no evidence for narrow (sigma approximately 5 MeV) signals in the Theta+ --> pK0(S) and Xi(--) --> Xi- pi- channels; our 95% C.L. upper limits (UL) for the inclusive production cross section times branching fraction B dsigma/dy/(y approximately 0) are (4-16) mub/N for a Theta+ mass between 1521 and 1555 MeV, and 2.5 mub/N for the Xi(--). The UL of the yield ratio of Theta+/Lambda(1520) < (3-12)% is significantly lower than model predictions. Our UL of B Xi(--)/Xi(1530)0 < 4% is at variance with the results that have provided the first evidence for the Xi(--).