Radioimmunoassay determination of tachykinin-related peptide in different portions of the central nervous system and intestine of the cockroach Leucophaea maderae

A radioimmunoassay was developed for insect tachykinin-related peptides with the use of an antiserum raised to the locust neuropeptide locustatachykinin I (LomTK I). Determination of tachykinin-related peptide was performed in different tissues of the cockroach Leucophaea maderae. The largest amounts of LomTK-like immunoreactivity (LomTK-LI) reside in the brain and in the midgut. Relatively large amounts were also found in the suboesophageal ganglion and throughout the ganglia of the ventral nerve cord, whereas smaller amounts of LomTK-LI were detected in the corpora cardiaca, foregut and hindgut. Extracts of unfused abdominal ganglia and midguts, respectively, were analysed by a combination of reversed phase high performance liquid chromatography, and radioimmunoassay for LomTK-LI. The extracts of abdominal ganglia and midguts both contain LomTK-LI material which separates in at least two major components. This LomTK-LI material had retention times corresponding approximately to those of synthetic LomTK I and II. Since the cellular source of LomTK-LI material in the foregut and hindgut was not known from earlier studies, we investigated these tissues by immunocytochemistry. We found that the LomTK-LI material associated with the foregut was in arborizing fibres in the oesophageal and gastric nerves and in the ingluvial ganglion. In the hindgut the muscle layer was innervated by immunoreactive fibres derived from cell bodies in the terminal ganglion. The amount of LomTK-LI material in other portions of the nervous system correlates well with previous immunocytochemical data. We conclude that L. maderae have two or more isoforms of tachykinin-related peptides in the nervous system and intestine and that these are present in various amounts in different parts of the central nervous system and intestine. The relative large amounts of LomTK-LI material in the suboesophageal ganglion, oesophageal nerve and associated ganglia and intestine indicate important roles of tachykinin-related peptides in feeding and digestion.     

Open-set speech perception in congenitally deaf children using cochlear implants

A review of the literature examining school-based prevention and treatment intervention programs for smokeless tobacco users is provided. Although few school-based prevention studies have been conducted, the results are promising. Many of the treatment studies that have been conducted, thus far, are limited due to the sample size and the lack of a control group. However, of the studies that have not had these limitations, the results are also promising. In general, studies show that intervention in the dental office can be effective and that group behavioral treatment may also improve cessation rates over minimal contact. On the other hand, pharmacological treatment, which has primarily focused on 2 mg nicotine gum, has not been found to be an effective treatment. Dentists are in an ideal position to advise and assist smokeless tobacco users to quit. The majority of smokeless tobacco users want advice and help from their dentists, and a significant number indicate that discussion of the negative oral effects from the use of smokeless tobacco has an impact on their desire to quit.     

Calibration of a prototype in vivo total body composition analyser using 14 MeV neutron activation and the associated particle technique

A prototype in vivo total body composition analyser has been constructed for determining the total body contents of nitrogen (TBN), carbon (TBC) and oxygen (TBO) in young experimental animals such as sheep or pigs by 14 MeV neutron activation using a commercially available associated particle sealed tube neutron generator (APSTNG). The instrument was calibrated by scanning phantoms of different sizes in the mass range 10-36 kg, filled with a mixture of elements as found in a normal human body. Good agreement was found between the measured and expected values of N, O and C when two phantoms of similar dimensions but of different composition were scanned. With four 15 cm x 15 cm cross section and 45 cm long NaI(T1) gamma detectors and a radiation dose of approximately 20 microSv due to neutrons, the expected precisions for a 28 kg animal, CV% (based on counting statistics) are N: 9.3, C: 2.3 and O: 1.4.     

The 1-hour advising session: helping students choose family practice

A case of chronic brucella endocarditis of a prosthetic valve is reported. The diagnosis of this infection was established by positive blood cultures and high brucella agglutination titre. The patient was successfully managed by combination of medical therapy (consisting of streptomycin, trimethoprim-sulphamethoxazole, rifampin and tetracycline) and surgery.     

Recombinant human interleukin-11 in experimental Pseudomonas aeruginosa sepsis in immunocompromised animals

The therapeutic potential of recombinant human interleukin-11 (rhIL-11) was tested in a neutropenic rat model that mimics the clinical consequences of myelosuppressive chemotherapy complicated by Pseudomonas aeruginosa sepsis. rhIL-11-treated animals (150 micrograms/kg intravenously every 24 h for 3 days) had reduced endotoxin levels (P < .05) and less pulmonary edema fluid (P < .001) and were protected (P < .01) against thinning and necrosis of the intestinal mucosa compared with the control group. The survival rate in rhIL-11-treated animals was 40% (19/47), whereas it was 0 (0 of 19) in the control group (P < .01). The addition of ciprofloxacin (10 mg/kg every 12 h) resulted in a survival rate of 9 (60%) of 15, while the combination of rhIL-11 and ciprofloxacin resulted in 100% survival (15/15; P < .05). These results indicate that rhIL-11 supports mucous membrane integrity of the alimentary tract and decreases the systemic inflammatory response to experimental gram-negative infection in immunocompromised animals.     

Bioterrorism as a public health threat

The threat of bioterrorism, long ignored and denied, has heightened over the past few years. Recent events in Iraq, Japan, and Russia cast an ominous shadow. Two candidate agents are of special concern--smallpox and anthrax. The magnitude of the problems and the gravity of the scenarios associated with release of these organisms have been vividly portrayed by two epidemics of smallpox in Europe during the 1970s and by an accidental release of aerosolized anthrax from a Russian bioweapons facility in 1979. Efforts in the United States to deal with possible incidents involving bioweapons in the civilian sector have only recently begun and have made only limited progress. Only with substantial additional resources at the federal, state, and local levels can a credible and meaningful response be mounted. For longer-term solutions, the medical community must educate both the public and policy makers about bioterrorism and build a global consensus condemning its use.