Competition-Mediated Antibiotic Induction in the Marine Bacterium Streptomyces tenjimariensis.

Microbial competition for limiting natural resources within a community is thought to be the selective force that promotes biosynthesis of antimicrobial compounds. The marine bacterium Streptomyces tenjimariensis produces the antibiotics istamycin A and B under select laboratory culture conditions; presumably these compounds serve an ecological role under natural conditions. Here we report results of a novel marine microbial competition experiment that examined the impact of co-culture of marine bacteria on istamycin production by S. tenjimariensis. Twelve of the 53 bacterial species tested (i.e., 22.6%) induced Istamycin production; this antibiotic also inhibited growth of the competitor colonies. These results suggest that marine bacterial metabolites serve an ecological role in countering competitive species.

Guillain-Barré syndrome: An unusual presentation of West Nile virus infection.

West Nile fever is a mosquito-borne febrile illness seen in Africa, Asia, and Europe, but reported in North America only once. The recent outbreak in New York City represents the first time this virus has been detected in North America. West Nile virus usually causes mild symptoms, though rarely it can cause neurologic diseases, with a fatal outcome or permanent neurologic sequelae. We describe an elderly patient with West Nile virus infection who presented with Guillain-Barré syndrome.

Keenamide A, a bioactive cyclic peptide from the marine mollusk Pleurobranchus forskalii.

Keenamide A (1), a new cytotoxic cyclic hexapeptide, was isolated from the notaspidean mollusk Pleurobranchus forskalii. Its structure was determined by NMR spectral data interpretation and chiral amino acid analysis. Keenamide A (1) exhibited significant activity against the P-388, A-549, MEL-20, and HT-29 tumor cell lines, but was inactive when evaluated against the D6 and W2 Plasmodium falciparum malarial clones.

Location of the vibratory segment in tracheoesophageal speakers.

The Singer-Blom tracheoesophageal puncture procedure for surgical-prosthetic voice restoration has proved to be a viable option for alaryngeal speech rehabilitation. Following tracheoesophageal puncture, occlusion of the tracheostoma shunts pulmonary air through the Blom-Singer prosthesis into the cervical esophagus. The pulmonary air passing through the cervical esophagus and into the hypopharynx causes a portion of the upper alimentary tract to vibrate in a manner similar to that of the pharyngoesophageal segment during the production of esophageal speech. To study the location and shape of the vibratory segment in tracheoesophageal speakers, videofluoroscopy and simultaneous voice recording were performed with 16 patients. To analyze the vibratory segment(s), photographs were made of the videotaped image while it was stopped during the patients' production of the /a/ sound. The most frequent location of the vibratory segment was in the lower third of the neck, which corresponds to cervical vertebrae C5 through C7. Five of the subjects had two separate vibratory segments and two other subjects had long vibratory segments. The vibratory segment(s) in tracheoesophageal speakers was found to be similar to the vibratory segment(s) in esophageal speakers.

Long-term results of the Blom-Singer speech rehabilitation procedure.

We report a 64% long-term success rate in our series of 66 patients who have undergone the tracheoesophageal puncture (TEP) procedure with follow-up ranging from one to 3 1/2 years. Poor motivation and compliance were the most common factors noted in patients who failed to obtain or maintain tracheoesophageal speech. Other problems causing failure were technical problems relating to the TEP and medical problems. The success rate in the last 24 cases of our series has improved to 83%. The "collared" prosthesis, more careful patient selection, and emphasis on a team approach seem to be important factors for the higher success rate. The Blom-Singer TEP procedure is a safe, simple, and effective means of alaryngeal communication for selected patients.

The Singer-Blom speech rehabilitation procedure.

Singer and Blom have recently reported a new surgical method for speech rehabilitation of the alaryngeal patient. The method consists of a tracheoesophageal, puncture (TEP) followed 2 to 3 days later by insertion of a silicone "duckbill" prosthesis which acts as a one-way valve allowing pulmonary air to enter and vibrate the esophagus but preventing aspiration. Along with more rapid acquisition of speech, the advantage of tracheoesophageal speech over esophageal speech is the greater volume of air flow through the vibrating segment of the esophagus, which allows smoother and more prolonged speech. Thirteen of our 18 patients (72%) who have undergone TEP are currently using tracheoesophageal speech. The complications associated with this procedure include the TEP tract closing, tracheal mucositis, stenosis of the tracheostoma, aspiration of the prosthesis, esophageal tear, and aspiration from the esophagus. Although we have encountered several problems, we enthusiastically endorse this procedure since it provides oral communication which is comparable to, and in many cases better than, that of the majority of esophageal speakers.