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In spring and winter generations of the variegated cutworm, Peridroma saucia (Hubner), female larvae are heaviest at the fourth day after the fifth ecdysis, their weight decreasing subsequently, but in summer generations their weight continues to increase until the sixth day. Spring and winter males show weight changes similar to those of females of the same generations, but the summer males, in contrast, maintain a constant weight from the fourth to the sixth day after ecdysis. In spring and winter generations, the hemolymph of female larvae has a higher refractive index than that of male larvae at the fourth and subsequent days after the fifth ecdysis, but in summer generations this difference is not evident until the sixth clay. The hemolymph refractive index increases during the prepupal stage. This is at variance with findings on various silkworm species which characteristically incorporate hemolymph proteins and amino acids into silk at this time. It is consistent with previously published work and the analysis of the present findings, to associate the variation in total wet weight and plasma refractive index with the interaction between progressive larval differentiation and metamorphosis phenomena. Upon these are superimposed fluctuations ascribed to sex, genetic change, and host-plant composition. The data obtained in this study suggest that, as a gauge of larval age in populations of healthy insects, plasma refractive index measurements may be more reliable than measurements of wet weight.

to the rapid advances in vertebrate virology. Explantation techniques have been adopted frequently by insect morphologists. However, for biochemical and virological purposes the use of cell suspensions is the most appropriate, and a number of investigations in this direction have been undertaken (St. Amand and Tipton, 1954 ; Martignoni, Zitcer and Wagner, 1958; Liu, Hsia and Kao, 1958 ; Aizawa and Vago, 1959) . Recently we have developed a method for the preparation of monolayer cultures using insect hemocytes. Al though these monolayers have the few disadvantages of primary cultures, they can be prepared easily and the cells are not subjected to treatment with enzymes or chelating agents. Insect blood is a good source of cells. Between 700,000 and 800,000 cells per larva are routinely obtained from the variegated cutworm, Peridronia saucia (Hiibner) [ = P. margaritosa (Haworth)], using the technique described in this paper. In comparison, the embryo of the green-striped grass hopper, Chortophaga viridifasciata (De Geer), produced about 13,000 cells after hyaluronidase and trypsin digestion (St. Amand and Tipton, 1954), and approxi mately 160,000 cells can be obtained from the three thoracic segments of a mature larva of P. saucia after treatment with snail hepatopancreas extract (Martignoni, Zitcer and Wagner, 1958). As vertebrate leukocytes have been used successfully for the propagation of viruses (Dunne, Luedke and Hokanson, 1958), and since some insect viruses are known to multiply in hemocytes, in vivo, an attempt to prepare hemocyte mono layers for the propagation of insect viruses seemed justified.

Histochemical and histological studies of midguts of larvae of the Douglas-fir tussock moth, Hemerocampa pseudotsugata , infected with cytoplasmic-polyhedrosis virus showed that the viral inclusion bodies formed in apicobasally oriented rows in goblet and columnar cells of the epithelium. Electron micrographs of ultrathin sections of infected cells in the late stages of the disease revealed that the cytoplasmic polyhedra, were surrounded by high numbers of virus particles, adjacent to the surface of the inclusion bodies. Biological assay gave an ld 50 estimate of 104 polyhedra/g larval weight. In our samples, the mean volume of the inclusion bodies was 7.7 μ 3 and the mean diameter of the virus particles was 56 mμ.

does not appear. First page follows. In 1957 Hughes (166) laid the basis for the “Annotated List and Bibliography” by cataloguing a series of 259 papers dealing with virus infections of insects. While Hughes’ list contains most of the important papers published on insect viruses and virus diseases, it does not include many reports which, even if not dealing primarily with virology or pathology, nonetheless contain valuable information for the insect pathologist. This first supplement adds 473 new references to the 259 already published in Hughes’ list. Almost all these papers have been seen in the original or, in a few eases, in photostatic copy of the original (as we are quite adverse to the not uncommon practice of quoting from quotations, thus perpetuating errors). Where the linguistic knowledge of the authors was lacking, translators were consulted; in some cases complete translations were available with the original publication. The present supplement, as in the list by Hughes, includes only a small proportion of the many papers in Japanese or Russian: those included were available in translation or contained a summary complete enough to derive sufficient information on the type of disease concerned. It is gratifying to know that a similar bibliographical survey is being completed at present in the U.S.S.R,. (S. Gershenson, personal communication, 1958). Titles of Japanese and Russian papers appear in translation only, the translation being that given in the summary of the original publication, Papers in English, French, German, and Italian are entered with their original titles and without translations. Translations and original titles appear for papers in Czech, Polish, and Croatian. As in Hughes’ list, an attempt was made to distinguish between nuclear polyhedrosis and cytoplasmic polyhedrosis whenever the information available permitted such a distinction. Those cases in which a polyhedrosis was involved, but without evidence to indicate the type of polyhedrosis, were recorded simply as “polyhedrosis.”

Glutamate-aspartate transaminase was assayed in the blood plasma of the noctuid larva Peridroma saucia (Hubner) during the course of nucleopolyhedrosis and granulosis. The blood-plasma transaminase activity was measured in LaDue-Wroblewski-Karmen units. In larvae with nucleopolyhedrosis, the activity of this enzyme was significantly elevated at the fourth and subsequent days after peroral inoculation with the virus. During the course of granulosis, the elevation was less marked: the first statistically significant increase was detected only at the fifth clay postinoculation. These differences in hyperenzymemia appear to be the result of dissimilar cytocidal activities of the two viruses concerned.

The possibility of preoperative prediction of pathologic complete response in rectal cancer has been studied in order to identify patients who would respond to neoadjuvant therapy and to individualize therapeutic strategies. Endoscopic ultrasound of the rectum is an accurate method for the evaluation of local tumor and lymph node invasion. Objective: To evaluate the potential of endoscopic ultrasound as a predictor of complete pathological response to neoadjuvant treatment in patients with locally advanced rectal cancer. Material and methods: Retrospective study of patients with rectal cancer from January 2014 to December 2016. Results: We obtained a statistical association between T stage by endoscopic ultrasound and complete pathological response (p = 0.015). It is not so for N, sphincter involvement, circumferential involvement and maximum tumor thickness (p = 0.723, p = 0.510, p = 0.233 and p = 0.114, respectively). When multivariate logistic regression analysis was applied to assess the degree of influence of the predictor variables on pathologic response, none of these variables was associated with complete pathologic response. Conclusion: Prediction of pathologic complete response in rectal cancer has been considered as the crucial point upon which treatments for rectal cancer could be individualized. So far, no imaging method has been able to demonstrate efficacy in predicting complete pathologic response, and in turn there is no direct association between any endosonographic finding that can accurately predict it.