Approximate formulas for the microbending loss in single-mode fibers

Some approximate formulas for calculating the microbending loss for single-mode fibers are given. The formulas are rather simple, yield good approximate values, and hence can be used to evaluate the microbending loss in fiber design.

Repair of upper ureteric obstruction with Boari flap and psoas hitch

A case of iatrogenic traumatic obstruction to both upper and lower ureters resulting in severe hydronephrosis is reported. Continuity and good functional result was achieved with a Boari flap and psoas hitch to the renal pelvis.

Serologic survey of human hydatid disease in high risk populations from central Tunisia. Preliminary results

The annual surgical incidence rate of hydatid disease in central Tunisia varies from 11.1 to 30.1 per 100,000 population depending on the district. In order to obtain more comprehensive data, we conducted a serologic survey in the district with the highest rate, using hemagglutination-inhibition to test 480 workers from a state farm and 190 inhabitants of villages in the neighborhood. The overall prevalence rate was 1.3% (9/670). Echotomography revealed liver cysts in all cases and the diagnosis was confirmed in the eight subjects who underwent surgery. If these preliminary results are confirmed by further surveys, mass screening might be considered in high risk districts.

Gastrointestinal tract complications of diabetes mellitus. Pathophysiology and management

Diabetes mellitus can affect every organ system, including large and small blood vessels, eyes, nerves, kidneys, and the gastrointestinal (GI) tract. We reviewed recent knowledge concerning the impact of diabetes on the gut. While the incidence of GI tract complications is usually considered relatively low, functional alterations have been demonstrated at every level in the gut and account for considerable morbidity in the diabetic population.

The nucleotide sequence of a new human repetitive DNA consists of eight tandem repeats of 66 base pairs

Three cloned human DNA fragments obtained from a fibroblast genomic DNA were sequenced and identified as containing members of the well-known 300-bp Alu family of interspersed, middle-repetitive DNA sequences. One of these cloned DNA fragments, p16, also contains members of a new repetitive DNA family, which repeats several thousand times in the human genome. Each member of the new 528-bp family consists of eight tandem repeats of a 66-bp sequence. An AluI recognition site is present at the same location in each repeat, and a 25-bp sequence occurs twice (as a tandem repeat) in each of the eight repeats. There is no sequence homology between the new 528-bp family and the 300-bp Alu family, and the new family lacks the flanking 7- to 20-bp direct repeats as well as the dAMP-rich sequences characteristic of the 300-bp Alu family. Construction of a putative evolutionary tree indicates that six duplication events are needed to give rise to the eight tandemly repeated 66-bp units in the new 528-bp family.

Interferon activity produced by interferon messenger RNA in Tilapiamosaiabica peters oocytes

The activities of interferon mRNA from various types of mouse cells have been studied using Tilapiamosaiabica peters oocytes (TPO) as the translation system. The translation activity of interferon mRNA in TPO was also compared with that in Xenopus laevis oocytes (XLO). The results obtained showed similar translation efficiency in both systems. The highest translation efficiency was observed when T. peters oocytes, microinjected with mRNA, were cultivated in Eagle's medium containing 0.01% HEPES and 0.5% NaHCO3 (pH 7.5) at 25 degrees C. pppA2' P5' A2' P5' A in concentration of 500 nM did not affect the translation of interferon mRNA in oocytes, but inhibition was demonstrated at 1 microM. A linear relationship was found between the amount of interferon mRNA injected and the antiviral activity of the translation products, suggesting that the amount of interferon mRNA can be determined by assaying the interferon activity of its translation product.

Peak homogeneity determination for the validation of high-performance liquid chromatographic assay methods

To validate high-performance liquid chromatographic assay procedures with regard to specificity, methods were developed to determine the homogeneity of the chromatographic peaks. These methods employed a rapid-scanning UV-visible spectrophotometer to monitor the chromatographic effluent. The absorption data were processed to nullify the signal due to the drug substances specifically, while allowing the detection of coincident impurities. Results from three model systems indicated the ability of these methods to detect as little as 0.1% of a coincident impurity.

[Epidemiological study of onchocercosis in 5 villages of the valley of the Sanaga (Cameroon)]

The study carried out in five villages in the Sanaga Valley of Cameroon was concerned with the prevalence of the disease, the level of infection and an evaluation of the effect of the parasites on the health of the people. Entomological data were also collected. The study was concerned with the onchocerciasis found in the forest area where the disease is hyperendemic. The males are infected moreoften than the females. Among the adults the skin and lymphatic lesions are extremly important. It was found that as the visual acuity diminishes with age, from age forty many for the people are blind. The villages most affected are those situated near the Sanaga rapids where there is a concentration of the breeding sites of the vectors.