Role of blood oxygenation saturation in ovarian cancer diagnosis using multi-spectral photoacoustic tomography

In photoacoustic tomography (PAT), a tunable laser typically illuminates the tissue at multiple wavelengths, and the received photoacoustic waves are used to form functional images of relative total haemoglobin (rHbT) and blood oxygenation saturation (%sO₂). Due to measurement errors, the estimation of these parameters can be challenging, especially in clinical studies. In this study, we use a multi-pixel method to smooth the measurements before calculating rHbT and %sO₂. We first perform phantom studies using blood tubes of calibrated %sO₂ to evaluate the accuracy of our %sO₂ estimation. We conclude by presenting diagnostic results from PAT of 33 patients with 51 ovarian masses imaged by our co-registered PAT and ultrasound system. The ovarian masses were divided into malignant and benign/normal groups. Functional maps of rHbT and %sO₂ and their histograms as well as spectral features were calculated using the PAT data from all ovaries in these two groups. Support vector machine models were trained on different combinations of the significant features. The area under ROC (AUC) of 0.93 (0.95%CI: 0.90-0.96) on the testing data set was achieved by combining mean %sO₂, a spectral feature, and the score of the study radiologist.     

Growth models for Salvinia molesta

Growth models have been developed using data from recent greenhouse studies on the effects of nitrogen, phosphorus and temperature on growth rates of Salvinia molesta Mitchell. Linear transformations were used for estimating Michaelis-Menten kinetic constants and a significant fit of the data was obtained. This has been confirmed by a comparison with field data. The growth models can be used for predicting the potential for Salvinia to remove nutrients from natural and polluted waters. Values thus obtained have a direct bearing on the design and costing of waste-water treatment ponds using Salvinia. Also, by predicting growth rates at particular temperatures and nutrient levels, the likelihood of successful control by biological agents can be assessed.     

A 13c-n.m.r. study of a di- and a tri-saccharide containing the α-d-galactopyranosyl group

The ¹³C-n.m.r. spectra of methyl 4-O-α-d-galactopyranosyl-α-d-galactopyranoside (1) and methyl 4-O-[4-O-(α-d-galactopyranosyl)-β-d-galactopyranosyl]-β-d-glucopyranoside (2) in D₂O were recorded. Comparison of these spectra with the spectra of methyl α-d-galactopyranoside (4) and methyl β-lactoside (5) provided substantial confirmation of the structures of 1 and 2.     

Immune restoration and/or augmentation of local xenogeneic graft versus host reaction by Cimetidine in vitro

The immunorestorative effect of Cimetidine in vitro on the T cell-induced local GVH reaction in vivo was studied in 43 cancer patients and 43 normal healthy donors. Both low dose (10(-5) M) and high dose (10(-4) M) Cimetidine induced significant, albeit partial, immune restoration among GVHR-negative cancer patients (p less than 0.05, p less than 0.01, respectively) with the high dose being significantly more effective (p less than 0.05). In contrast, similar Cimetidine doses induced only moderate augmentation (p greater than 0.05) among GVHR-positive cancer patients and a marginal one among normal healthy donors. In the latter 2 groups, Cimetidine was found to be occasionally detrimental in that it induced a conversion from a positive to a negative GVH reaction. These results support the concept of anti-suppressor cell activity ascribed to Cimetidine. However, the possibility of a detrimental effect should be born in mind in planning future clinical trials. We propose that the use of Cimetidine be limited to cancer patients with documented increase in suppressor cell activity associated with defective T cell function under close serial monitoring.     

Destruction of corals and other reef animals by coral spawn slicks on Ningaloo Reef,Western Australia

In March 1989, most of the corals near Coral Bay, off the north-western coastline of Australia, spawned several nights earlier than usual. Flood, rather than ebb, tides at the time of spawning combined with light north-west winds and low swell conditions to restrict the dispersal of coral propagules and, as a result, large amounts of coral spawn were trapped in the bay, forming extensive slicks. Fish and other animals began to die almost immediately, and over the next few days, over 1 million fish, representing at least 80 species, were washed ashore. A survey of the benthic communities revealed extensive mortality of corals and other reef animals over an area of about 3 km². Live coral cover in this area decreased from 42.9% to 9.4% and several large coral colonies up to 10 m in diameter were killed. The observed mortality was presumably the result of hypoxia (oxygen depletion) created initially by the respiratory demand of the coral spawn and maintained by the biological oxygen demand of the decomposing spawn slicks and dead animals. Anecdotal reports of corals and other reef animals dying in the vicinity of coral spawn slicks on other reefs in Western Australia suggest that this phenomenon may be a relatively common event on shallow coral reefs where coral mass spawning occurs. These records and observations document, for the first time, a new source of natural disturbance that has a significant influence on the community structure of some coral reefs.     

Campylobacter Enteritis on Hopi and Navajo Indian Reservations—Clinical and Epidemiologic Features

From June 22 through September 30, 1981, stool specimens from 522 Hopi and Navajo outpatients were cultured because of diarrheal illnesses at the Keams Canyon Indian Health Service Hospital, Arizona. Campylobacter jejuni was isolated from the specimens of 26 (5%) of the patients. This pathogen was found as frequently as Shigella in patients younger than 2 years or older than 20 years, but was significantly less common in the 2 to 20-year age group (P<.000001). Campylobacter enteritis was indistinguishable clinically from shigellosis in adult patients, but in children younger than 5 years, a rectal temperature higher than 38°C (100.5°F) was significantly more common with Shigella than with Campylobacter infection (P=.003). In a field study of 20 families, we found that households with a case of Campylobacter enteritis were more likely than age- and community-matched controls to own farm animals (P=.05), but were not more likely to own household pets. C jejuni is less common than Shigella as a cause of summer seasonal diarrhea and dysentery among the Hopi and Navajos; the striking differences in the age-specific rates of these two infections suggest different routes of transmission.