The behavioral genetics of colony defense in honeybees: Genetic variability for guarding behavior

Guard honeybees stand at the entrance of colonies and facilitate the exclusion of nonnestmates from the colony. In this study, we examined the hypothesis that genetic variability among individuals in colonies might explain variability in guarding activity. To do this, we cross-fostered honey bees between colonies with high-defensive responses and colonies with low-defensive responses in alarm pheromone tests. Individuals from high-defensive colonies were more likely to guard in their own colonies (controls) than cross-fostered bees from low-defensive colonies. Cross-fostered high-defensive bees also were more likely to guard in low-defense colonies. These results support the hypothesis that interindividual differences in guarding behavior are at least partially under genetic control. A positive correlation between number of guards and response to alarm pheromone demonstrates a link between behaviorally separated components of the overall defensive response.This work was supported by NSF Grant BNS 8605604.     

Risk factors and obstetric complications associated with macrosomia.

OBJECTIVE: Macrosomia is associated with adverse maternal outcomes. The objective of this study was to characterize the epidemiology of macrosomia and related maternal complications. METHOD: Live births (146,526) were identified between 1995 and 1999 in the Kaiser Permanente Medical Care Program's Northern California Region (KPMCP NCR) database. Bivariate and multivariate analyses were performed for risk factors and complications associated with macrosomia (birth weight >4500 g). RESULT: Male infant sex, multiparity, maternal age 30-40, white race, diabetes, and gestational age >41 weeks were associated with macrosomia (p<0.001). In bivariate and multivariate analyses, macrosomia was associated with higher rates of cesarean birth, chorioamnionitis, shoulder dystocia, fourth-degree perineal lacerations, postpartum hemorrhage, and prolonged hospital stay (p<0.01). CONCLUSION: Macrosomia was associated with adverse maternal outcomes in this cohort. More research is needed to determine how to prevent complications related to excessive birth weight.     

Non-Hodgkin's lymphomas in 137 patients aged 70 years or older: a retrospective European Organization for Research and Treatment of Cancer Lymphoma Group Study

The results of a European Organization for Research and Treatment of Cancer (EORTC) retrospective study on non-Hodgkin's lymphoma (NHL) in elderly patients (greater than or equal to 70 years of age) seen in Europe in 1984 are reported. A precodified form was sent to 55 European institutes in order to evaluate the incidence of NHL in the elderly with regard to natural history, treatment-related toxicity, response, and survival. Thirteen institutes participated in the study. One hundred thirty-seven cases of NHL were observed in the elderly during 1984, making up 28% of the total number of NHL seen in those institutes. The median age was 77 years; 21% of the patients had favorable (low-grade) and 73% unfavorable (intermediate- and high-grade) histology, according to the Working Formulation. Stage at presentation was localized (I and II) in 60% and advanced in 37% of the patients. Most of the physicians used standard therapy regimens at reduced doses, from the beginning of the treatment. Sixty patients (44%) underwent a "conservative" treatment (one or two antineoplastic drugs or local field radiotherapy) and 77 (56%) an "aggressive" treatment (polychemotherapy regimens or extended field radiotherapy). Response was similar between the two treatment groups, but severe and lethal toxicity was significantly higher among patients treated with aggressive therapy. Prospective randomized studies are clearly needed to define the optimal treatment in elderly patients with advanced unfavorable NHL.     

Morphogenesis of the fibrous sheath in the marsupial spermatozoon

The spermatozoon fibrous sheath contains longitudinal columns and circumferential ribs. It surrounds the axoneme of the principal piece of the mammalian sperm tail, and may be important in sperm stability and motility. Here we describe its assembly during spermiogenesis in a marsupial, the brush-tail possum, and compare its structural organization with that of eutherian mammals, birds and reptiles. Transmission electron microscopy showed that possum fibrous sheath assembly is a multistep process extending in a distal-to-proximal direction along the axoneme from steps 4 to 14 of spermiogenesis. For the most part, assembly of the longitudinal columns occurs before that of the circumferential ribs. Immunohistochemical and immunogold labelling showed that fibrous sheath proteins are first present in the spermatid cytoplasm; at least some of the proteins of the sheath precursors differ from those in the mature fibrous sheath. That immunoreactivity develops after initiation of chromatin condensation suggests that fibrous sheath proteins, or their mRNAs, are stored within the spermatid cytoplasmic lobule prior to their assembly along the axoneme. These findings are similar to those in laboratory rats, and thus suggests that the mode of fibrous sheath assembly evolved in a common ancestor over 125 million years ago, prior to the divergence of marsupial and eutherian lineages.     

Two patients with chronic lymphocytosis of large granular lymphocytes; benign or premalignant?

In two female patients aged 44 and 86 years, a chronic lymphocytosis was observed caused by a proliferation of large granular lymphocytes (LGL). The first one had been successfully treated for Hodgkin lymphoma long before, the second had diabetes mellitus type 2. Immunophenotyping showed the proliferating lymphocytes to be natural killer (NK) cells. In contrast to the proliferation of B- and T-lymphocytes, data on the prognosis and treatment of NK-lymphocytosis are very scarce. A literature search revealed three major clinical entities in which LGL proliferate: at one end of the spectrum we see the very aggressive NK-LGL leukaemia, at the other, NK-lymphocytosis, a benign chronic disorder, in between is the relatively indolent chronic T-LGL leukaemia. Both patients suffered from chronic NK-lymphocytosis with a favourable course; there were no further symptoms 4 and 2 years, respectively, after the diagnosis. In cases of prolonged lymphocytosis of unknown origin, immunophenotyping of the lymphocytes is essential. Only in this way can one arrive at the proper diagnosis and reach conclusions as to the prognosis and the possible methods of treatment.     

The predictive value of cytogenetic diagnosis after CVS: 1500 cases

The cytogenetic results of 1500 chorionic villus samples (CVS) are presented. In these 1500 samples, 23 samples (1.5 per cent) could not be provided with a diagnosis because of laboratory failure. This failure rate dropped from 3 per cent in the first 500 samples to 0.2 per cent in the last 500. In the remaining 1477 samples, 58 (3.9 per cent) chromosomal aberrations were found. Of these, 21 (36 per cent) proved not to represent the karyotype of the fetus proper. Predictive values of (different groups of) chromosomal aberrations in CVS are calculated. The impact of (differences between) the predictive value for some major chromosomal aberrations is discussed. A tissue- and chromosome-specific selection mechanism is postulated.     

Disposable Plastic Centrifuge Bowls for Separation of Red Blood Cells and Plasma in the Processing of Frozen Blood

A simplified method for automated red blood cell processing is described. The method uses sterile, disposable plastic centrifuge bowls with attached tubing and reagent solutions. It can be used for the separation of red blood cells and plasma and the glycerolization and deglycerolization of red blood cells for storage in the frozen state. Data is presented on operational performance of the equipment and on red blood cell yields and post-thaw transfusion survival.     

Unusual germ cell organization in the seminiferous epithelium of a murid rodent from southern Asia, the greater bandicoot rat, Bandicota Indica

In the greater bandicoot rat, Bandicota indica, of south-east Asia, nine cell associations were documented in the testicular seminiferous epithelium. In about 10% of the tubule cross sections two or more cell associations occurred and, furthermore, some of the generations of germ cells within the cell associations were sometimes either out of phase, or missing, in the tubule cross sections. These features, together with the fact that this species has a highly pleiomorphic sperm head shape, are somewhat reminiscent of those of the seminiferous epithelium in humans and some other primates but not of common laboratory rodents. This species could thus be a good model for investigating irregular patterns of spermatogenesis in naturally occurring wild species of rodent.