Global assessment of the status of coral reef herbivorous fishes: evidence for fishing effects.

On coral reefs, herbivorous fishes consume benthic primary producers and regulate competition between fleshy algae and reef-building corals. Many of these species are also important fishery targets, yet little is known about their global status. Using a large-scale synthesis of peer-reviewed and unpublished data, we examine variability in abundance and biomass of herbivorous reef fishes and explore evidence for fishing impacts globally and within regions. We show that biomass is more than twice as high in locations not accessible to fisheries relative to fisheries-accessible locations. Although there are large biogeographic differences in total biomass, the effects of fishing are consistent in nearly all regions. We also show that exposure to fishing alters the structure of the herbivore community by disproportionately reducing biomass of large-bodied functional groups (scraper/excavators, browsers, grazer/detritivores), while increasing biomass and abundance of territorial algal-farming damselfishes (Pomacentridae). The browser functional group that consumes macroalgae and can help to prevent coral-macroalgal phase shifts appears to be most susceptible to fishing. This fishing down the herbivore guild probably alters the effectiveness of these fishes in regulating algal abundance on reefs. Finally, data from remote and unfished locations provide important baselines for setting management and conservation targets for this important group of fishes.

Enhanced pneumocystis carinii activity of new primaquine analogues.

New analogues of the venerable antimalarial drug primaquine have been synthesized and bioassayed in vivo against Pneumocystis carinii, a life-threatening infection common among immunosuppressed patients. Two of these new compounds are significantly more active than primaquine itself, and provide new information for future drug design and development in this area.

Wave-front control of a large-aperture laser system by use of a static phase corrector.

In large-aperture, ultrahigh-intensity laser systems, such as Vulcan at the Rutherford Appleton Laboratory, one of the most important factors that determines the ultimate on-target focused intensity is the wave-front quality of the laser pulse. We report on a wave-front analysis carried out on Vulcan to determine the nature and contribution of the aberrations present in the laser pulse that effectively limited the available on-target intensity. We also report on a significant improvement to the wave-front quality that was achieved by static correction of the main aberration, resulting in an increase of focused intensities by a factor of 4.

Symptomatic and clinical improvement in morbidly obese patients with gastroesophageal reflux disease following Roux-en-Y gastric bypass.

BACKGROUND: Patients who suffer with gastroesophageal reflux Disease (GERD) endure a worsening of symptoms as their weight increases. When medical treatment of this condition in the morbidly obese patients fails, surgical intervention may be indicated. Choosing a procedure which not only helps achieve weight control but which also relieves symptoms and complications of GERD is the goal. We present a review of patients who have undergone Roux-en-Y Gastric Bypass (RYGBP) and related procedures for this disease. METHODS: One hundred eighty-eight patients undergoing surgery for morbid obesity and for GERD in 1992-1996 were contacted by mail or phone. All of these patients had undergone preoperative esophagogastroduodenoscopy to grade the severity of their disease. Their preoperative symptoms were compared to those experienced postoperatively. RESULTS: One hundred thirty patients underwent a RYGBP with modified Hill fundopexy, 22 patients underwent a distal gastrectomy with modified Hill fundopexy, 8 patients underwent distal gastrectomy alone and 28 patients underwent RYGBP alone. There have been no deaths. There were nine surgical complications, eight early and one at 2.5 years postoperation. Follow-up is 4-48 months. The average BMI dropped from 43 to 30.2 kg/m2. Whereas all patients were on some form of medical therapy before surgery, only 14 reported the need for medication postoperatively. CONCLUSIONS: Surgical intervention for weight control and treatment of GERD has been highly successful in our experience both with respect to weight control and to the reduction of reflux symptoms. Depending upon endoscopic and operative findings a RYGBP with or without an antireflux procedure can provide dramatic improvement. Gastrectomy with antireflux modifications is appropriate in selected cases.

H-2 antigen requirements in the in vitro induction of SV40-specific cytotoxic T lymphocytes.

T cytotoxic cells generated to syngeneic SV40 virus transformants lyse only SV40 target cells that are syngeneic at the H-2 locus. In contrast, SV40-specific tumor transplantation immunity shows no requirements for syngeneic H-2. Inoculation of allogeneic or even xenogeneic transformants will confer immunity to a challenge of syngeneic SV40 tumor cells. The experiments described here represent an attempt to reconcile these apparently conflicting observations. In our hands, generation of SV40-specific T cytotoxic cells in vitro requires both in vivo priming and secondary in vitro sensitization. We have found that priming for a secondary syngeneic-restricted response requires only that the cell employed be SV40 transformed. That is, priming may be accomplished with syngeneic, allogeneic, or xenogeneic SV40 transformants. Thus, the apparent lack of H-2 restriction in vivo immunity does not eliminate a role for the H-2-restricted cytotoxic T cell in tumor transplantation immunity.

Repetitive vacuum ultraviolet xenon excimer laser.

A repetitive, tunable, high-power vacuum ultraviolet laser operating on the 172-nm bound-free transition in xenon has been developed for use in photochemistry, selective excitation spectroscopy, and in the generation of coherent radiation in the XUV spectral region. A compact high-voltage generator is employed in conjunction with a coaxial cold-cathode diode to pump high-pressure xenon at a repetition rate of up to 10 Hz, though at present gas heating limits the operation of the laser to 0.5 Hz. The apparatus has been designed for compatibility with fluorine, and is consequently a suitable pumping source for the rare gas halide exciplex lasers. The gas handling techniques which enabled reliable, reproducible laser action to be achieved in xenon for several hundred pulses are described.

Thyroid parameters in iodine deficiency.

Thyroid Plasma Clearance and Free Thyroxine Index were compared in 20 Zambians with iodine deficiency with 12 Zambians and 10 expatriates without iodine deficiency. Mean clearance was similar in the non-deficient groups (19 and 22 ml/min.) but much higher (123 ml/min.) in the deficient group. Mean Free Thyroxine Index was similar in the non-deficient groups (11.2 and 10.3) but significantly lower (8.2) in the deficient group. A relationship between iodine deficiency and low income was seen. No racial difference was apparent.

Phase I study of ftorafur, an analog of 5-fluorouracil.

Ftorafur, a furanyl analog of 5-fluorouracil (5-FU), is reported to be five to six times less toxic and possibly more effective in cancer of the breast and colon than 5-FU. The drug was synthesized, formulated, and utilized in toxicologic studies, and then in 24 patients with advanced incurable malignancies. When Ftorafur is given by intravenous push, it results in immediate flushing, dizziness, nausea, retching, and in some cases transient hypotension. These immediate side effects are largely eliminated by administering the drug slowly by infusion. In patients, 60 mg/kg of Ftorafur given i.v. daily for up to 10 days resulted in mild toxicity. However, 80 mg/kg given i.v. daily for 7 days resulted in severe toxicity, with nausea, vomiting, stomatitis, leukopenia, and thrombocytopenia. These studies confirm those of the Russian investigators as to toxicity and dosage, even with a different method of administration more convenient for therapy. Phase II studies are presently being carried out to compare the effectiveness of Ftorafur and 5-FU.

Repeatability of Principal Components in Samples: Normal and Non-Normal Data Sets Compared.

The asymptotic theory of the distribution of the latent roots and vector of principal components analysis (PCA) of samples has hitherto been tied t multivariate normal (MVN) distributions. However, much real behavior dat are not normal. The results of the present study show, using arguments base on Monte Carlo methods, that if there is enough meaningful structure in th population, then PCA of samples of data with multivariate non-normal (NN distribution may provide answers relative to the "true" population principal components (PC) of comparable reliability to PCA of samples of MVAT data.