Biomedical subjects

A G Cohen

Publications and source records attributed to A G Cohen.

At least 19 recordsLinked to original sources

PubMed2001

(De)constructing dimensions.

We construct renormalizable, asymptotically free, four-dimensional gauge theories that dynamically generate a fifth dimension.

Journal Article↗

PubMed2001

Weekly irinotecan and cisplatin in advanced non-small cell lung cancer: a multicenter phase II study.

The combination of weekly irinotecan (CPT-11) and monthly cisplatin has shown promising activity in advanced non-small cell lung cancer (NSCLC) in previous Phase I and II studies. However, same-day administration of these agents may better exploit their therapeutic synergy and minimize toxicities. This multicenter Phase II study was undertaken to evaluate the efficacy and safety of a combination of weekly CPT-11 and weekly cisplatin in patients with advanced NSCLC. Patients with chemotherapy-naive stage IIIB or IV NSCLC were treated with repeated cycles of therapy comprising weekly treatment with both cisplatin and CPT-11 for 4 weeks, followed by a 2-week rest. The starting doses of CPT-11 and cisplatin were 65 and 30 mg/m2, respectively. Treatment was continued until the occurrence of disease progression, unacceptable toxicity, or a maximum of six cycles. Fifty patients were enrolled. The median age was 59 years (range, 44-79 years). Eastern Cooperative Oncology Group performance status was 0 in 22 patients, 1 in 19 patients, and 2 in 9 patients. Seven and 43 patients had stages IIIB and IV disease, respectively. Five patients had brain metastasis. Patients received a median of three 6-week cycles (range, 1-6). The objective response rate was 36% (18 of 50; 95% confidence interval, 24-54%) and included 18 partial responses. Median time to tumor progression was 6.9 months (range, 0.6-15.2). The median survival was 11.6 months (range, 0.16-21.9 months), and the 1-year survival rate was 46%. Grade 3/4 nonhematological toxicities included vomiting (12%) and diarrhea (26%). Grade 3/4 hematological toxicities included anemia (14%), neutropenia (26%), and thrombocytopenia (14%). Relative dose intensities for CPT-11 and cisplatin were 89 and 62%, respectively. Weekly combined administration of CPT-11 and cisplatin achieved a promising overall response rate, median time to tumor progression, and median survival in patients with stage IIIB/IV NSCLC. The regimen was well tolerated, and the planned dose intensity was well maintained. Further evaluation of this combination in NSCLC is warranted.

Adult↗

PubMed1993

Acquired immunodeficiency syndrome-like illness associated with systemic Mycoplasma fermentans infection in a human immunodeficiency virus-negative homosexual man.

A 35-year-old homosexual man developed a composite nodal Kaposi's sarcoma and peripheral T-cell lymphoma that were associated with a peripheral blood CD4-positive lymphocyte count of only 43/mm3. The patient subsequently developed Pneumocystis carinii pneumonitis and eventually died due to disseminated Cryptococcus neoformans. Numerous premortem tests for the presence of human immunodeficiency virus (HIV) types 1 and 2 were negative by the enzyme-linked immunosorbent assay, Western blot, viral isolation, and polymerase chain reaction techniques. Postmortem evaluations for HIV-1, HIV-2, human T-cell lymphotropic virus (HTLV)-I, and HTLV-II also were negative by polymerase chain reaction, immunofluorescence assays, and viral isolation. A systemic infection by Mycoplasma fermentans, however, was documented by immunohistochemistry and polymerase chain reaction in premortem and postmortem tissues. This recently recognized human pathogen has produced systemic infections in patients with the acquired immunodeficiency syndrome (AIDS) and in previously healthy non-AIDS patients who characteristically have a fulminant flu-like illness. Additionally, M fermentans has enhanced the cytopathic effect of HIV in in vitro studies and has produced fatal wasting illnesses with terminal lymphopenia in inoculated adult silvered leaf monkeys. This report is the first description of an association between M fermentans infection and an AIDS-like illness in an HIV-negative individual. The etiology of the severe immunosuppression in this patient and the associated role of M fermentans remain to be determined by further investigations.

Acquired Immunodeficiency Syndrome↗

PubMed1989

Post removal prior to retreatment.

Removing posts from root canals prior to endodontic retreatment is often a challenge. The Gonon post removing system (Thomas Extracteur De Pivots; FFDM-Pneumat, Bourges, France) is safe and efficient and can be used for anterior, bicuspid, and even molar teeth. The Gonon system is illustrated with one clinical case.

Crowns↗

PubMed1988