Extranodal non-Hodgkin lymphoma involving the muscles of mastication.

Involvement of the skeletal muscle by non-Hodgkin lymphoma (NHL) is unusual. The most commonly affected muscles are those of the extremities, pelvis, and gluteal regions; rarely are the muscles in the head and neck involved. We report the clinical, CT, and MR imaging findings in two patients with extranodal NHL in the head and neck region involving the muscles of mastication. One patient was immunocompetent and had lymphoma that arose within the muscles; the other was a patient with AIDS who had disseminated disease at diagnosis. In both patients, the involved muscles were isodense with normal muscles on CT scans. On MR images, the infiltrated muscles were isointense with normal muscles on the T1-weighted sequence and hyperintense on the fast spin-echo T2-weighted sequence, with variable enhancement after administration of intravenous contrast material.

Functional role of Ca2+ currents in graded and spike-mediated synaptic transmission between leech heart interneurons.

We used intracellular recording and single electrode voltage-clamp techniques to explore Ca2+ currents and their relation to graded and spike-mediated synaptic transmissions in leech heart interneurons. Low-threshold Ca2+ currents (activation begins below -50 mV) consist of a rapidly inactivating component (I(CaF)) and a slowly inactivating component (I(CaS)). The apparent inactivation kinetics of I(CaF) appears to be influenced by Ca2+; both the substitution of Ca2+ (5 mM) with Ba2+ (5 mM) in the saline and the intracellular injection of the rapid Ca2+ chelator, bis-(o-aminophenoxy)-N,N,N',N'-tetraacetic acid (BAPTA), from the recording microelectrode, significantly increase its apparent inactivation time constant. The use of saline with a high concentration of Ba2+ (37.5 mM) permitted exploration of divalent ion currents over a broader activation range, by acting as an effective charge carrier and significantly blocking outward currents. Ramp and pulse voltage-clamp protocols both reveal a rapidly activating and inactivating Ba2+ current (I(BaF)) and a less rapidly activating and slowly inactivating Ba2+ current with a broad activation range (I(BaS)). Low concentrations of Cd2+ (100-150 microM) selectively block I(BaS), without significantly diminishing I(BaF). The current that remains in Cd2+ lacks the characteristic delayed activation peak of I(BaS) and inactivates with two distinct time constants. I(BaF) appears to correspond to a combination of I(CaF) and I(CaS), i.e., to low-threshold Ca2+ currents, that can be described as T-like. I(BaS) appears to correspond to a Ca2+ current with a broad activation range, which can be described as L-like. Cd2+ (100 microM) selectively blocks spike-mediated synaptic transmission between heart interneurons without significantly interfering with low-threshold Ca2+ currents and plateau formation in or graded synaptic transmission between heart interneurons. Blockade of spike-mediated synaptic transmission between reciprocally inhibitory heart interneurons with Cd2+ (150 microM), in otherwise normal saline, prevents the expression of normal oscillations (during which activity in the two neurons consists of alternating bursts), so that the neurons fire tonically. We conclude that graded and spike-mediated synaptic transmission may be relatively independent processes in heart interneurons that are controlled predominantly by different Ca2+ currents. Moreover, spike-mediated synaptic inhibition appears to be required for normal oscillation in these neurons.

Surface sensibility of the floor of the mouth and tongue in healthy controls and in radiated patients.

Increased areas of anesthesia in the oral cavity have been shown to significantly impair oral function in normal individuals. In patients who undergo oral cavity reconstruction, loss of sensation plays a major role in producing disturbances in postoperative oral function. Free tissue transfer techniques have permitted the problem of sensory loss to be addressed through the use of sensate cutaneous free flaps, in which microneural anastomoses are performed between a sensory nerve supplying the flap and a recipient nerve in the head and neck. To critically assess the results of such reconstructions, the effect of sensory restoration on oral cavity rehabilitation must be studied. As a first step toward this goal, normal values for sensory discrimination of the floor of mouth and tongue are needed. Previous studies of oral sensation failed to examine the ventral tongue and floor of mouth. The purpose of this study is to determine the surface sensibility of these regions in healthy patients and in patients who received radiation therapy to the oral cavity. Sensation was evaluated using static and moving two-point discrimination in 90 healthy subjects divided equally into three age groups: 20 to 40 years, 41 to 60 years, and 61 to 80 years. In addition, 20 patients who received radiation therapy were studied. The mucosa of the dorsal and ventral aspects of the lateral tongue, tongue tip, and floor of mouth was examined. The tongue tip is the most sensitive area, followed by the dorsal lateral tongue, ventral lateral tongue, and floor of mouth. The effects of age and radiation therapy on sensory discrimination are discussed.(ABSTRACT TRUNCATED AT 250 WORDS)

Combined chemotherapy and radiation therapy for advanced carcinoma of the cervix.

Ten patients with advanced squamous cell carcinoma of the uterine cervix received induction chemotherapy with cis-platinum, mitomycin-C, vincristine, and bleomycin (BOMP) over a 5 week period, followed by radiotherapy with concomitant weekly cisplatinum. Two patients were FIGO stage I-B barrel-shaped, five were stage II-B, and three were III-B. All patients responded to induction chemotherapy with five complete and five partial responses. At the completion of radiation therapy, nine patients had negative biopsies. One patient never reached a complete response and died of distant metastasis. Another underwent total exenteration for a central recurrence and was found to have microscopic paraaortic lymph node involvement. A third recurred in the parametrium. Two patients with barrel-shaped tumors underwent extrafascial hysterectomies; both had negative specimens and tolerated surgery well. Although follow-up is short, this new approach for advanced carcinoma of the cervix yielded excellent results and was well tolerated.

Transmission block to simplify combined pelvic and inguinal radiation therapy.

A homogeneous dose distribution of radiation to inguinal lymph nodes and deep pelvic structures can be achieved with use of a transmission block over the central portion of a large anterior pelvic-inguinal portal, together with a smaller posterior field. This relatively simple technique permits individualization of isodose distributions and eliminates the problems of matching abutting portals. Reproducibility of daily setup and optimization of machine utilization are both improved.

Antibody-mediated radiotherapy.

Antibodies that react with antigens on the surface of tumor cells but not normal cells have great potential for cancer detection and therapy. If radiolabeled without loss of immunologic specificity, such antibodies may be able to deliver cytoxic amounts of radiation. Target-cell specificity and a high extraction coefficient are necessary with any radionuclide in order to minimize normal tissue irradiation. Tumor-cell-retention time and the rate of catabolized radionuclide will also influence ultimate applicability. Among the unanswered questions for choosing a radionuclide is the choice of particle emitter. Although classic beta emitters have been used in a number of clinical situations, they have not had a major impact on disease outcome except in diseases of the thyroid. Unfortunately, Auger emitters such as iodine 125 are cytotoxic only when localized within close proximity to the genome. On the other hand, alpha emitters such as astatine 211 eliminate the need for subcellular sequestration but not cell-specific localization.

Pulmonary toxicity of bischloronitrosourea: report of a case with transient response to corticosteroid therapy.

A case of interstitial pulmonary fibrosis secondary to bischloronitrosourea (BCNU) in a 49-year-old man with carcinoma of the pancreas is reported. The diagnosis was suggested by deteriorating oxygenation, restrictive changes on pulmonary function studies, and increased interstitial markings radiographically in the lower lung fields. Transbronchial biopsy excluded infectious etiologies and confirmed a bland nonspecific interstitial pulmonary fibrosis of recent origin. The patient responded dramatically to high dose corticosteroids, but relapsed when the corticosteroids were decreased. We believe there is now convincing evidence that prolonged use of BCNU can cause potentially fatal interstitial pulmonary fibrosis. Patients should be followed with serial chest radiographs and pulmonary function studies. If diagnosed early, this process may respond to high dose corticosteroid therapy.

Idiotypic specificities of anti-Rh antibodies.

Idiotypic antibodies were produced in rabbits to Rh antibodies isolated from the serum of an individual with high Rh antibody titer. These antisera after absorption with blood IgG failed to react with immunoglobulins lacking anti-Rh activity. They agglutinated cells coated with the immunizing antibody to high titers. Two other anti-Rh coats out of 22 tested also were agglutinated but to considerably reduced titers indicating a degree of anti-Rh cross specificity. Four other antisera made to red cells coated with different anti-Rh antibodies showed definite but weaker idiotypic specificity. Both the idiotypic and cross-idiotypic antigens of the Rh antibodies were completely blocked when univalent fragments of the Rh antibodies were bound to antigen on the red cell.