Effect of two superovulation treatments on subsequent fertility in the confined dairy cow

During a 13-month period, 64 lactating dairy cows of 2 genetic lines, Holstein and crossbred, housed indoors year-round were subjected to 2 superovulations and embryo collections within 112 days post partum. Half of the follicle stimulating hormone (FSH) treatments were given in a descending dosage regimen (Treatment A; 6.5 mg, 5.5 mg, 4.5 mg, and 3.5 mg, twice a day, total 40 mg) over 4 days; the remaining half of the treatments were administered in a constant dosage regimen (Treatment B) of 5 mg twice a day over 4 days. There were no significant differences due to treatment in the number of cows stimulated (more than 2 corpora lutea) nor in the number of ova/embryos collected. However, embryos were obtained from more cows (P<0.05) when treated with the descending dosage regimen. More cows (P<0.05) were stimulated by the superovulatory treatment during the first period than during the second period regardless of the regiment used, treatment A or B. More embryos (P<0.05) were obtained from the Holstein line than from the crossbred line. Fifty-two cows were inseminated at least once after the second embryo collection. Overall, 41 cows (79%) became pregnant after the second collection, requiring up to 4 services. These results suggest that the reproduction of dairy cattle housed indoors year-round is not adversely affected by 2 superovulation treatments and embryo collections within 112 days post partum. The question as to whether the administration of FSH is more efficacious in a descending dosage regimen or a constant dosage regimen was not resolved.     

Lampyridae (Coleoptera): A plethora of mollicute associations

Beetles (Coleoptera) harbor many species ofAcholeplasma andSpiroplasma (division Tenericutes, class Mollicutes). Mollicutes were isolated from guts and/or hemocoels of firefly beetles (Lampyridae) from the United States (Maryland and West Virginia), Ecuador, and Tobago. Firefly beetles were frequent hosts for the group XIV spiroplasma, isolated from Ellychnia corrusca, and the group XIX spiroplasma, isolated fromPhoturis spp. The most unusual feature of the firefly-mollicute association is the carriage of four Mycoplasma species. Recent phylogenetic studies indicate that these species are members of a clade that includes a vertebrate pathogen,Mycoplasma mycoides. The high rate of occurrence ofMycoplasma species (which are, otherwise, infrequent in insects) in lampyrid beetles suggests that the association is significant. The unusual light-producing physiology of lampyrids (which is dependent on large pools of energy) and the production of large amounts of cardenolides from cholesterol (a critical growth factor for many mollicutes) may favor colonization by mollicutes. Offprint requests to: K. J. Hackett.     

Biological properties of human melanoma cells in culture

Summary Three human melanoma cell lines derived from one primary and two metastatic tumors from three different patients were characterized for growth properties usually associated with malignant transformation; these include cell morphology, growth rate, saturation density, growth in semisolid media, colony-forming ability on contact-inhibited monolayers of normal fibroblasts and epithelial cells, and tumorigenicity in immunosuppressed mice. Variations in expression of aberrant properties were evident among the lines. One of the metastatic lines satisfied all the parameters of malignancy tested and the other showed a number of these properties, whereas the primary essentially fulfilled only one. These results suggest that cultured melanoma cells reflect the clinical variability often observed among melanoma patients and the metastatic melanoma seems to display a higher degree of malignant transformation than the primary. THis work was supported in part by USPHS Grant No. 5 T01 AI00332-06 from the National Institutes of Health, Contract E73-2001-N01-CP-3-3237 from the Virus Cancer Program of the National Cancer Institute, and USPHS Grant No. 0H00714-02 from the National Institute for Occupational Safety and Health.     

Career choices of physicians 15 years after entering medical school.

The career status of 149 graduates of the University of Toronto faculty of medicine who entered in 1958 and graduated in 1962 was determined in 1973. The response rate to the mailed questionnaire was 96.6%. Of the graduates 4.7% were not practising medicine, 2.0% stated that medicine was not their primary gainful activity and 4.1% were untraceable or unknown. Of the 24 women in the class 17 (70.8%) were practising at least 76% of their time and 4 (16.7%) were practising 26 to 75% of their time. General practice or family medicine had been chosen by 39.0% of the class and a specialty by 55.7%; 5.4% were unknown or untraceable. The place of longest residence before entrance to university was a good predictor of ultimate location of practice but not of type of practice.     

Meeting report on the 2019 international symposium of molecular design breeding in animals (Yangling,China) with the consensus on genome-editing agricultural animals and their regulation

Transgenic Research -     

Spectrum of Ocular Manifestations in?CLN2-Associated Batten (Jansky-Bielschowsky)?Disease Correlate with Advancing Age and Deteriorating Neurological Function

Background

Late infantile neuronal ceroid lipofuscinosis (LINCL), one form of Batten’s disease is a progressive neurodegenerative disorder resulting from a CLN2 gene mutation. The spectrum of ophthalmic manifestations of LINCL and the relationship with neurological function has not been previously described.

Methods

Patients underwent ophthalmic evaluations, including anterior segment and dilated exams, optical coherence tomography, fluorescein and indocyanine green angiography. Patients were also assessed with the LINCL Neurological Severity Scale. Ophthalmic findings were categorized into one of five severity scores, and the association of the extent of ocular disease with neurological function was assessed.

Results

Fifty eyes of 25 patients were included. The mean age at the time of exam was 4.9 years (range 2.5 to 8.1). The mean ophthalmic severity score was 2.6 (range 1 to 5). The mean neurological severity score was 6.1 (range 2 to 11). Significantly more severe ophthalmic manifestations were observed among older patients (p<0.005) and patients with more severe neurological findings (p<0.03). A direct correlation was found between the Ophthalmic Severity Scale and the Weill Cornell Neurological Scale (p<0.002). A direct association was also found between age and the ophthalmic manifestations (p<0.0002), with older children having more severe ophthalmic manifestations.

Conclusions

Ophthalmic manifestations of LINCL correlate closely with the degree of neurological function and the age of the patient. The newly established LINCL Ophthalmic Scale may serve as an objective marker of LINCL severity and disease progression, and may be valuable in the evaluation of novel therapeutic strategies for LINCL, including gene therapy.     

Fundamental differences in promoter CpG island DNA hypermethylation between human cancer and genetically engineered mouse models of cancer

Genetic and epigenetic alterations are essential for the initiation and progression of human cancer. We previously reported that primary human medulloblastomas showed extensive cancer-specific CpG island DNA hypermethylation in critical developmental pathways. To determine whether genetically engineered mouse models (GEMMs) of medulloblastoma have comparable epigenetic changes, we assessed genome-wide DNA methylation in three mouse models of medulloblastoma. In contrast to human samples, very few loci with cancer-specific DNA hypermethylation were detected, and in almost all cases the degree of methylation was relatively modest compared with the dense hypermethylation in the human cancers. To determine if this finding was common to other GEMMs, we examined a Burkitt lymphoma and breast cancer model and did not detect promoter CpG island DNA hypermethylation, suggesting that human cancers and at least some GEMMs are fundamentally different with respect to this epigenetic modification. These findings provide an opportunity to both better understand the mechanism of aberrant DNA methylation in human cancer and construct better GEMMs to serve as preclinical platforms for therapy development.