Chest radiography and beta-2-microglobulin levels in HIV-seronegative and HIV-seropositive African patients with pulmonary tuberculosis

To examine the relationship between radiographic features, serum beta-2-microglobulin (beta-2-M) levels, results of sputum-smear microscopy and outcome, we performed a retrospective study of 99 HIV-seropositive and 162 HIV-seronegative patients with pulmonary tuberculosis (TB) in Dar es Salaam, Tanzania. Radiographic features of primary TB were more common and features of postprimary TB less common in HIV-seropositive compared to seronegative patients (50% vs 31%, p < 0.002; and 40% vs 63%, p < 0.001), respectively). HIV infection had a strong independent effect on the beta-2-M levels. Among HIV-infected patients radiographic findings of primary TB were significantly more often associated with beta-2-M levels of > 4 mg/l than features of postprimary TB (71.1% vs 44.4%, p < 0.02). In patients with features of postprimary TB, acid-fast bacilli were more often detected in sputum smears than in patients with primary TB (65% vs 47%, p > 0.05, in HIV-seropositive patients; and 63% vs 31%, p < 0.001) in seronegative patients). The observed mortality was too low to identify radiographic predictors of survival. We conclude that HIV-infected patients with features of primary pulmonary TB are likely in an advanced stage of HIV infection and deserve close supervision during anti-tuberculous therapy.

Expression of BCL-2 protein enhances the survival of mouse fibrosarcoid cells in tumor necrosis factor-mediated cytotoxicity

Tumor necrosis factor (TNF) kills some types of tumor cells in vitro and participates in tumor elimination in vivo. TNF has been shown to kill cells by altering their mitochondria structurally and functionally. The oncogene BCL-2 codes for a protein located in the inner membrane of mitochondria which is able to inhibit the commitment to cell death in various cell types. We have therefore investigated whether TNF-mediated killing of the cell line L929 could be modulated by expression of the protein BCL-2. We report here that L929 cells transfected with a BCL-2 expression vector have an increased survival compared to wild type cells after TNF challenge. The protective effect is greatest at moderate TNF concentrations and is still significant at concentrations that killed 100% of wild type cells. The action of BCL-2 is selective inasmuch as cells are not protected against other cytotoxic agents blocking various mitochondrial functions. We show that cells expressing BCL-2 have a higher mitochondrial membrane potential (delta psi) than wild type cells. The increase in delta psi could be linked with the enhanced survival of cells after TNF challenge. Indeed, we found that treatment of wild type L929 cells with the ionophore nigericin, which increases delta psi, protects them even at high TNF concentrations.

[Electromagnetic articulography (EMA) studies on orofacial movement functions]

For judging the influence of orofacial motor functions on the development and function of the dentoalveolar system objective methods are required. Electromagnetic Articulography (EMA) is a new device based on an inductive measuring principle. Using miniature receiver coils placed on the tongue dorsum or the velar margin, movements of multiple points on orofacial structures in the midsagittal plane can be recorded. The application of EMA on the examination of tongue and velum motor activity during speech production and deglutition is demonstrated. First results of sagittal tongue movement during swallowing in normals are reported. Examples from current studies, using EMA in the field of tongue dysfunction, orofacial motor coordination and velopharyngeal closure are demonstrated and the possible perspective of EMA-application is discussed for dental research and functional treatment of CLP-patient.

A retrospective in vitro study of the impact of anti-diabetics and cardioselective pharmaceuticals on breast cancer

BACKGROUND

In a retrospective controlled study, a tumor-protective effect, regarding breast cancer, was determined for the medicines metformin and glitazone (anti-diabetics), bisoprolol, and propranolol (cardioselective β1 adrenoceptor antagonists). Our main goal was to provide evidence, showing the tumor-protective effects of beta-blockers and of antidiabetics via investigations in vitro.

MATERIALS AND METHODS

Four different medicines were tested in cell cultures: Propranolol: 2.4 mg/ml and 0.3 mg/ml; bisoprolol: 0.1 mg/ml and 0.05 mg/ml; metformin: 7.5 mg/ml, 2.5 mg/ml, and 0.15 mg/ml; and glitazone: 2.5 mg/ml, 0.15 mg/ml, and 0.05 mg/ml. The human breast cancer cell lines MCF7 and BT20 (estrogen receptor-positive and -negative; ATCC; cell density: 5×10(5) cells/ml) were used. Both cell lines were cultured under sterile conditions in incubators at 37°C, with a humidified atmosphere of 5% CO(2). The influences of the drugs were determined through cytotoxicity and proliferation assays and performance of a hydrogen peroxide assay. Morphological observations (light microscopy) and metabolic investigations (pH value, glucose) were also performed.

RESULTS

The application of the beta-blocker propranolol resulted in highly cytotoxic effects (>90%) in both cell lines. In contrast, bisoprolol did not have any effects, neither in cytotoxicity tests nor in cell proliferation assays. The anti-diabetic metformin had a higher cytotoxic influence on the BT20 than did on the MCF7 cell line. The cell proliferation of BT20 was significantly inhibited after the addition of 2.5 mg/ml metformin and of 2.5 mg/ml glitazone. The application of glitazone also resulted in an increase of hydrogen peroxide and a decrease of the pH value.

CONCLUSION

The strongest cytotoxic effect was observed with propranolol suggesting that, in clinical practice, this pharmaceutical can be used in patients with breast cancer who have hypertension. A specific clinical recommendation for anti-diabetics is not yet possible.

[Intraoperative neuromonitoring of the recurrent laryngeal nerve--routine use in thyroid gland surgery]

We present a simple and reliable method for identification of the recurrent nerve by intraoperative stimulation. An electromyographic record from the vocal muscle is obtained using a bipolar needle electrode inserted through the cricothyroid membrane. The recurrent nerve could be easily identified in 176 cases out of 181 nerves at risk (97.2%). We have not seen any cases of recurrent nerve paralysis and discuss the advantages of intraoperative neuromonitoring as a routine procedure.

Hepatic microsomal dealkylations. Inhibition by a tyrosine-copper (II) complex provided with superoxide dismutase activity

The effect of a divalent copper-tyrosine complex has been evaluated in rat liver microsome-catalyzed dealkylations. The copper complex, which is provided with superoxide dismutase activity, inhibits at micromolar concentrations aminopyrine, p-nitroanisol, and 7-ethoxycoumarin dealkylations. It has also been found that cumene hydroperoxide-supported p-nitroanisol demethylation, the formation of a 440 nm species, and the formation of superoxide radicals are inhibited by the divalent copper complex. On the other hand, 3-chloroperbenzoic acid has been found to support a copper complex-insensitive 7-ethoxycoumarin dealkylation. Oxygen uptake by rat liver microsomes is also inhibited by the copper complex. The data support the concept that the copper complex acts as a superoxide dismutase at the level of a cytochrome P-450 intermediate species, liganded with superoxide anions.

[Diagnosis and treatment of tuberculous lymphadenitis of the neck]

The incidence of extrapulmonary tuberculosis is rising. The patients are predominantly immigrants and HIV-infected persons. Tuberculous lymphadenitis of the neck is the most common presentation, in the Netherlands about 200 patients a year. Fine needle aspiration with auramine/Ziehl-Neelsen stain investigation, culture and cytological examination is the diagnostic procedure of choice. If this fails to be conclusive excision biopsy is the next step. If the diagnosis is suspected on clinical, epidemiological, laboratory and bacteriological (presence of acid-fast bacilli) or cytological/histological grounds, treatment is always started, awaiting culture results. The principles for treatment are the same as for pulmonary tuberculosis. On the basis of the available literature it can be proposed to shorten the duration of treatment from 9 to 6 months.