Dielectric response of aligned semiconducting single-wall nanotubes.

We report measurements of the full intrinsic optical anisotropy of isolated single-wall carbon nanotubes (SWNTs). By combining absorption spectroscopy with transmission ellipsometry and polarization-dependent resonant Raman scattering, we obtain the real and imaginary parts of the SWNT permittivity from aligned semiconducting SWNTs dispersed in stretched polymer films. Our results are in agreement with theoretical predictions, highlighting the limited polarizability of excitons in a quasi-1D system.

Comparative measures of single-wall carbon nanotube dispersion.

Model composites of DNA-wrapped single-wall carbon nanotubes in poly(acrylic acid) are used to evaluate metrics of nanotube dispersion. By varying the pH of the precursor solutions, we introduce a controlled deviation from ideal behavior. On the basis of small-angle neutron scattering, changes in near-infrared fluorescence intensity are strongly correlated with dispersion, while optical absorption spectroscopy and resonant Raman scattering are less definitive. Our results represent the first systematic comparison of currently accepted measures of nanotube dispersion.

Intrapleural therapy for malignant pleural effusions. A randomized comparison of bleomycin and tetracycline.

Between December 1985 and August 1988, there were 115 patients at 13 centers who were entered on a randomized comparison of tetracycline and bleomycin for treatment of malignant pleural effusions. Fifteen patients were not treated, primarily due to rapid progression of systemic cancer. Fifteen patients entered on a high-dose regimen of bleomycin (120 units) were excluded from this analysis (following early closure of that arm), leaving 85 patients randomized to low-dose bleomycin (60 units; 44 patients) or tetracycline (1 g; 41 patients). Patients were required to have a cytologically positive pleural effusion, good performance status (0, 1, or 2), lung reexpansion following tube thoracostomy with drainage rates of 100 ml/24 or less, no prior intrapleural therapy, no prior systemic bleomycin therapy, no chest irradiation, and no recent (four weeks) change in systemic therapy. A total of 11 patients (five with bleomycin and six with tetracycline) were not evaluable due to technical problems with tube drainage (one), loss to follow-up (two), sudden death due to pulmonary embolus (one), and rapid progression of systemic disease (seven). There were no clinically significant differences in demographic factors, primary site, performance status, or presence of metastases other than pleural effusion. Overall survival did not differ between the two groups. Median time to recurrence or progression of the effusion was 32 days for tetracycline-treated patients and at least 46 days for bleomycin-treated patients (p = 0.037). The recurrence rate within 30 days of instillation was 36 percent (10/28) with bleomycin and 67 percent (18/27) with tetracycline (p = 0.023) (not all patients were restudied in the first 30 days). By 90 days the corresponding recurrence rates were 30 percent (11/37) for bleomycin and 53 percent (19/36) for tetracycline (p = 0.047). Toxicity was similar between groups.

Abolition of herpes simplex cytopathic effect after treatment with peroxidase generated hypothiocyanite.

HSV1 suspensions were pre-incubated in a lactoperoxidase thiocyanate oxidizing system before inoculation in MRC5 fibroblast cultures. This pre-treatment could either delay or even abolish the HSV1 cytopathic potentiality. The effect was found to be time-dependent.

[Antiseptic properties of saliva and metabolism of activated oxygen in neutrophils: comparison of the 2 enzymatic bactericidal systems and of their behavior in an acid environment]. / Pouvoir antiseptique de la salive et métabolisme de l'oxygène activé dans les neutrophiles: comparaison de deux systèmes enzymatiques bactéricides et de leur comportement en milieu acide.

Growth control of anaerobes in the oral cavity, is secured--among other means--by: 1) phagocytosis of opsonized bacteria; 2) synthesis of hypothiocyanite by the salivary peroxidase system. The former may be inhibited by bacterial acid byproducts. As for the salivary hypothiocyanite, it proved itself able of hindering in vitro the growth of bacterial strains known as customary periodontal pathogens. Its possible effectiveness in vivo remains however hypothetical in the case of deep gingival pockets according to the poor diffusion there of salivary components.

Fluctuation of the biochemiluminescence from PMN leukocytes in a family with a high prevalence of severe periodontitis.

Rapidly progressive periodontal disease was found in three patients belonging to three different generations of the same family. Beyond the clinical inspection, blood examination allowed measurements of the luminol enhanced biochemiluminescence from the circulating PMN leukocytes. Abnormally low values were recorded in the affected individuals (75, 84 and 138 mVolts per 10(6) cells) whereas a sample of healthy individuals exhibited photonic values from 240 up to 910 mVolts per 10(6) cells. These abnormal values, however, were not constantly recorded. They gave way to higher PMN activity indices after the patients had been treated either by antibiotics, scaling, debridement or classical pocket cleaning.

Anaerobes and short-chain fatty acids in crevicular fluid from adults with chronic periodontitis.

Pathogeny of adult chronic periodontitis is still unclear. Bacteriological and chemical analysis of crevicular fluid have shown, in active sites of the disease, a simultaneous presence of anaerobes and their major by-product: short-chain fatty acids. The last can decrease "in vitro" the neutrophil intracellular pH, whenever these cells are incubated in an acid medium. Clinical investigations are scarce which hold out data useful to attempt verifying this possible physiopathological mechanism. This work shows the presence of anaerobes in the active periodontal pockets, together with the presence of short-chain fatty acids likely to reach a concentration level comparable to that used for inhibiting neutrophils "in vitro". Forthcoming studies should investigate about a possible intracellular pH drop in the neutrophils and other cells of the inflamed periodontium.

Protein kinase C deficiency in juvenile chronic myeloid leukemia: a case report.

Protein kinase C activity was assayed in morphologically differentiated and undifferentiated myeloid cells of a 13-month-old girl with chronic myeloid leukemia. A reduced protein kinase C activity was seen in the morphologically differentiated neutrophils, while the activity in the leukemic cells was higher to that of normal neutrophils from control subjects.

Inhibition of human polymorphonuclear leukocytes phagocytosis and protein-kinase-C activity by low pH concentrations.

PMN leukocytes from circulating blood, were investigated using the following parameters: chemiluminescence, superoxide generation, exocytic degranulation, lactoferrin, myeloperoxydase and protein-kinase-C activities. The results did not allow to point out any significative discrepancy between samples collected from either patients suffering of periodontal disease or healthy individuals. However, the phagocytic ability (as measured by light emission and superoxide production) was found to be severely inhibited in both instances, when PMN leukocytes were incubated in the presence of succinic acid. Similarly, protein-kinase-C activity in these cells, collapsed when the pH was brought down to 5.5. These data and the available literature indicate that pH decrease as well as succinic acid release in the crevicular fluid, may play a role in the pathogeny of chronic periodontitis in adults.

Postchemotherapy resection of residual tumor in limited stage small cell lung cancer.

To determine the feasibility of post-chemotherapy resection of residual tumor in small cell lung cancer, 24 selected patients with limited-stage disease were evaluated for exploratory thoracotomy. All 24 patients achieved partial or complete clinical response to chemotherapy and were considered adequate medical candidates for surgical resection. Fifteen patients underwent a lobectomy or pneumonectomy, 13 of whom had residual tumor in the resected specimen. Of the nine remaining patients, seven had no tumor found on biopsy at thoracotomy and two had unresectable mediastinal node involvement. No chemotherapy was administered postoperatively in any patient until disease progression or relapse was documented. Median survival for the entire group was 19 months and did not differ according to the surgical procedure performed. Nineteen patients had relapse. Patients undergoing biopsy only recurred locally in six of seven cases a median of five months post-thoracotomy (range one to six months). Two "biopsy only" patients were tumor free at 34+ and 56+ months. Local recurrence was observed in six of 12 resected patients, while six patients experienced only extrathoracic metastases. Median time to recurrence for resected patients was also five months. Four resected patients experienced late recurrence 16 to 36 months postoperatively and were alive with tumor at 29+ to 42+ months. Two resected patients were tumor-free at 13+ and 37+ months. Post-chemotherapy surgical resection was feasible in limited-stage patients and improved local control of disease.

Resection of thoracic and abdominal teratoma in patients after cisplatin-based chemotherapy for germ cell tumor. Late results.

Fifty-one patients with primary testicular (N = 46) or mediastinal germ cell cancer (N = 5) were treated from April, 1975, through May, 1981, and had teratoma resected from residual disease after cisplatin-based combination chemotherapy. All patients had normal serum markers before resection of pulmonary (N = 12), mediastinal (N = 5), thoracoabdominal (N = 8), supraclavicular (N = 1) or abdominal disease (N = 25). Teratoma was classified as mature teratoma (N = 29), immature teratoma (N = 15), or immature teratoma with non-germ cell elements (N = 7). Thirty of 51 (60%) patients remain free of recurrent disease, whereas 20 patients have either recurrent carcinoma (N = 10) or teratoma (N = 10). One patient has a presumed second malignancy. After additional chemotherapy, four patients with recurrent carcinoma are alive and disease free and six have died. After an additional operation, eight of 10 patients with recurrent teratoma are long-term survivors. In four patients the initial relapse of carcinoma developed more than 2 years after therapy; in an additional patient carcinoma recurred after a 32 month disease-free survival period. Univariate factors predicting for relapse include tumor burden, immature teratoma with non-germ cell elements, and site (mediastinum), whereas only immature teratoma with non-germ cell elements and site predicted for survival. Immature teratoma and mature teratoma had similar relapse-free intervals and overall survival intervals. According to a multivariate analysis, primary tumor site at the mediastinum is the most significant adverse factor predictive for both relapse and survival (two of five patients survived). This study appears to support the various preclinical models that demonstrate multipotential capabilities of teratoma. Complete surgical excision of teratoma remains the most effective treatment with continued close follow-up recommended for high-risk patients (immature teratoma with non-germ cell elements, large tumor burden, or primary mediastinal tumors.

Teratoma following cisplatin-based combination chemotherapy for nonseminomatous germ cell tumors: a clinicopathological correlation.

From April 1975 through May 1981, 51 patients had teratoma resected from residual disease following cisplatin-based combination chemotherapy. All patients had normal serum markers before resection of abdominal (25), lung (12), mediastinal (5), thoracoabdominal (8) or other (1) disease. Teratoma was classified as mature in 29 cases, immature in 15 or immature with nongerm cell elements in 7. Of the 51 patients 31 (61 per cent) remain free of recurrent disease, while 20 either had recurrent carcinoma (10) or teratoma (10) requiring further therapy. Nine patients died, including 1 in whom angiosarcoma developed, which was thought to be secondary to previous radiation therapy. In 4 patients the initial relapse of carcinoma developed beyond 2 years after resection. Univariate factors predicting for relapse include tumor burden, immature teratoma with nongerm cell elements and site (mediastinum), while only immature teratoma with nongerm cell elements and site predicted for survival. Patients with immature teratoma had a comparable relapse-free and over-all survival as those with mature teratoma. Using a multivariate analysis, primary tumor site at the mediastinum was the most significant adverse factor predictive for relapse and survival. This study appears to support the various pre-clinical models that demonstrate multipotential capabilities of teratoma. Complete surgical excision of teratoma remains the most effective treatment with continued close followup recommended for high risk patients (immature teratoma with nongerm cell elements, large tumor burden and primary mediastinal tumors) with resected teratoma.

Deoxythymidine and deoxycytidine incorporation into DNA in B leukemic cells.

Measurements of radioactive DNA after incubation of normal and B leukemic peripheral mononuclear cells, from c-ALL and CLL with labeled deoxythymidine (dTh) and deoxycytidine (dCt) showed that for dTh, incorporation into DNA was similar for normal and c-ALL cells but lower in B-CLL cells and that for dCt, incorporation was highest in c-ALL and lowest in CLL cells. These results contrast with those of dTh and dCt kinase activities; the former has been previously found elevated in c-ALL cells, and the latter is found, in the present study, similar in the three groups tested.

Purine enzyme levels in rheumatoid arthritis.

We studied purine metabolism in rheumatoid arthritis (RA), adenosine deaminase (ADA), 5'-nucleotidase (5'NU) and purine nucleoside phosphorylase (PNP) activities by measuring the circulating mononuclear cells of patients with RA and healthy controls. Patients had significantly lower levels of ADA and 5'NU but not of PNP than controls. The decreases could not be related to age, antiinflammatory therapy, decreased percentages of T cells or imbalance between major T cells subsets. Differences in cell maturation or traffic could account for our observation. Alternatively, abnormalities of purine metabolism are not definitely excluded in RA if the lower enzyme activity is not sufficient to perform the metabolic steps.

Enzymes of purine metabolism in B-chronic lymphocytic leukemia.

In order to study if enzymes of purine metabolism could be used as cell markers in B-chronic lymphocytic leukemia (B-CLL), the activities of adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), and 5'-nucleotidase (5'N) were repeatedly measured in blood mononuclear cells from B-CLL patients and were compared to those obtained in normal controls. Enzyme activities in patients were also compared to other biological parameters indicative of B-CLL to activities of ADA and PNP in erythrocytes. Results show that B-leukemic cells display abnormal enzyme patterns: subnormal ADA activity is characteristic; 5'N activity is depressed in 60% of the cases but increased in 15%. An inverse relationship between PNP activity and corresponding lymphocytosis is observed in leukemic but not in normal cells. The enzymatic anomalies seem to be linked to the presence of an unusual peripheral lymphocytic population, induced by the leukemic process. Indeed, ADA and PNP are not abnormal in erythrocytes. In untreated nonevolutive patients, the enzyme profile tends to remain stable throughout the course of the illness; normalization of enzyme patterns in treated patients occurs only when therapy induces improvement in T and B cell distribution.

Thymidine kinase and thymidine phosphorylase activities in various types of leukaemia and lymphoma.

Thymidine kinase (TK) isoenzymes and thymidine phosphorylase (TP) activities have been measured in peripheral mononuclear cells of patients with acute lymphoblastic and monoblastic leukaemia or B-chronic lymphocytic leukaemia, as well as in normal subjects, and also in lymph node cells from patients with non-Hodgkin's lymphoma, with Hodgkin's disease and with benign adenopathies. TK1 isoenzyme activity was highest in acute lymphoblastic leukaemia and in centroblastic lymphoma. Then in progressively decreasing order appeared the Hodgkin's disease values, the centroblastic centrocytic lymphoma values and the benign reactive lymph node cell values. When compared to normal blood mononuclear cells, TP was greatly decreased in acute lymphoblastic leukaemia and slightly but significantly decreased in chronic leukaemia. Monoblastic cells exhibited a unique enzyme pattern; moderately increased TK1 activity and high TP activity. Our results suggest that both enzymes are indicative of the maturation status of leukaemic cells from B lineage. They demonstrate that in lymph node cells, TK1 reflects the proliferative status of both malignant and non-malignant cells and that in monoblastic cells the synthesis of dTMP through de novo synthesis is favoured.

Methylthioadenosine phosphorylase and purine nucleoside phosphorylase in B-chronic lymphocytic leukemia.

Enzymes of purine metabolism have potential utility as biological markers of normal lymphocytes and their neoplastic counterparts. The activity of two of them, methylthioadenosine phosphorylase (MTA phosphorylase) and purine nucleoside phosphorylase (PNP) were measured in peripheral mononuclear cells from 11 patients with B-chronic lymphocytic leukemia (B-CLL) and compared with those obtained in cells from 10 normal volunteers. An inverse relationship between the two phosphorylases was demonstrated in patients, with higher MTA-phosphorylase and lower PNP activities than in control subjects.

The importance of one-stage median sternotomy and retroperitoneal node dissection in disseminated testicular cancer.

More than 350 patients with testicular germ cell cancer have been treated with cisplatin combination chemotherapy. Seventy-two with metastases to the thorax who had operation are discussed here. In a subgroup of 24 patients with additional retroperitoneal disease, a one-stage median sternotomy was performed in 18 patients, and a thoracotomy in 6, with retroperitoneal node dissection. Seventeen patients had similar pathological lesions in the thorax and retroperitoneum; in 7, the lesions differed. There was no operative mortality in the entire group. Overall, chemotherapy altered the metastases to mature teratoma in 28 patients, and 27 are long-term survivors. Among 22 patients with fibrotic, necrotic masses, 19 are long-term survivors; 6 of the 22 with persistent carcinoma had chemotherapy postoperatively and are long-term survivors. The overall cure rate for patients with disseminated testicular cancer is approximately 80%. Among those who had a one-stage thoracoretroperitoneal procedure, long-term survival is 83%; for the entire thoracic surgical group, it is 74%.