Patterns in Prescription Opioids, Benzodiazepines, and Stimulants Filled by Pregnant Medicaid Beneficiaries

This study analyzes patterns in prescriptions filled by pregnant Medicaid beneficiaries for opioids, benzodiazepines, and stimulants.

Predictors of severe and critical disease in pregnant women with SARS-CoV-2

BACKGROUND/OBJECTIVE

SARS-CoV-2 continues to spread widely in the US and worldwide. Pregnant women are more likely to develop severe or critical illness than their non-pregnant counterparts. Known risk factors for severe and critical disease outside of pregnancy, such as asthma, diabetes, and obesity have not been well-studied in pregnancy. We aimed to determine which clinical and pregnancy-related factors were associated with severe and critical COVID illness in pregnancy.

STUDY DESIGN

This was a retrospective cohort study of women with confirmed intrauterine pregnancy and positive nasopharyngeal swab for SARS-CoV-2 who presented to an academic medical center in New York City from 1 March 2020 to 1 July 2020. Severe and critical COVID-19 disease was defined by World Health Organization criteria. Women with severe/critical disease were compared to women with asymptomatic/mild disease. Continuous variables were compared with Mann-Whitney or t-test and categorical variables were compared using chi-square and Fisher's exact. Statistical significance was set at p < .05. Multivariable logistic regression was performed including variables that were significantly different between groups.

RESULTS

Two hundred and thirty-three patients were included, 186 (79.8%) with asymptomatic/mild disease and 47 (20.2%) with severe/critical disease. Women with asymptomatic/mild disease were compared to those with severe/critical disease. Women with severe/critical disease were more likely to have a history of current or former smoking (19.6 vs. 5.4%, p = .004), COVID-19 diagnosis in the 2nd trimester (42.6 vs. 11.8%, p = .001), and asthma or other respiratory condition (21.3 vs. 7.0%, p = .01). Women with severe/critical disease were more likely to have cesarean delivery (35.5 vs. 15.6%, p < .01) and preterm delivery <37 weeks (25.8 vs. 3.8%, p < .01). After adjustment, history of smoking remained significantly predictive of severe/critical disease [aOR 3.84 (95% CI, 1.25-11.82)].

CONCLUSION

Pregnant women with a history of smoking, asthma, or other respiratory condition, and COVID-19 diagnosis in the second trimester of pregnancy were more likely to develop severe/critical disease. These findings may be useful in counseling women on their individual risk of developing the severe or critical disease in pregnancy and may help determine which women are good candidates for vaccination during pregnancy.

Psychological and Structural Barriers to Immigrant Community Participation: The Experience of Peruvians in Santiago de Chile

Community participation can be considered a pillar for the promotion of social justice and well-being for immigrants in new countries. Participation may be influenced by different forms of oppression which decrease opportunities for immigrants to be engaged. The present study explores the difficulties that Peruvian immigrants encountered and still encountering to participate in Santiago de Chile through in-depth qualitative interviews. Eighteen semi-structured interviews were conducted with Peruvian leaders of Ethnic Community Based Organizations (ECBOs) in Santiago de Chile. Interviews focused on the community engagement of Peruvians highlighting the difficulties they encountered when deciding whether to engage and throughout the process of carrying out their commitment, along with their perceptions when trying to engage their compatriots. The present study contributes to the literature in three aspects. First, it focused on the phenomenon of South-South migration. Secondly, it delved into the psychological and structural barriers that immigrants' experience, considering their disadvantaged conditions. Thirdly, it used Situational Analysis, along with the constructionist drift of Grounded Theory, which is widely used in critical, qualitative research, and is sensitive to producing situated knowledge. Coding and mapping analysis identified experiences related to historical trauma, transnational bonds, and dominant master narratives in both countries as well as challenges due to balancing time and priorities, surviving institutional deterrents, and inter-organizations competitiveness. Finally, transnational commitments, mechanisms of social disconnection, and under valuated rights that Peruvians may live in Chile were pointed out. These results intend to have practical implications for immigrants and for community psychologists.

Mapping of quantitative trait loci controlling tick [Riphicephalus (Boophilus) microplus] resistance on bovine chromosomes 5, 7 and 14

Differences in domestication and selection processes have contributed to considerable phenotypic and genotypic differences between Bos taurus and Bos indicus cattle breeds. Of particular interest in tropical and subtropical production environments are those genetic differences between subspecies that underlie the phenotypic extremes in tolerance and susceptibility to parasite infection. In general, B. taurus cattle are more susceptible to ectoparasites than B. indicus cattle in tropical environments, and much of this difference is under genetic control. To identify genomic regions involved in tick resistance, we developed a B. taurus x B. indicus F(2) experimental population to map quantitative trait loci (QTL) for resistance to the Riphicephalus (Boophilus) microplus tick. About 300 individuals were measured for parasite load in two seasons (rainy and dry) and genotyped for 23 microsatellite markers covering chromosomes 5, 7 and 14. We mapped a suggestive chromosome-wide QTL for tick load in the rainy season (P < 0.05) on chromosome 5. For the dry season, suggestive (P < 0.10) chromosome-wide QTL were mapped on chromosomes 7 and 14. The additive effect of the QTL on chromosome 14 corresponds to 3.18% of the total observed phenotypic variance. Our QTL-mapping study has identified different genomic regions controlling tick resistance; these QTL were dependent upon the season in which the ticks were counted, suggesting that the QTL in question may depend on environmental factors.

Association of BoLA-DRB3.2 alleles with tick (Boophilus microplus) resistance in cattle

Losses caused by bovine tick burdens in tropical countries have a tremendous economic impact on production systems. Besides reducing production, this parasite can cause death in the most susceptible animals. The use of commercial acaricides has been the major method of control, but their misuse has led to tick resistance to many chemicals. More recently, vaccines have been used in some countries without solving the problem completely. An alternative could be the development of resistant animals and the use of genetic markers and candidate genes that could help with the enormous task of selecting resistant animals. The bovine lymphocyte antigen genes (BoLA) have been shown to be associated with some parasitic infestations and disease incidence. Thus, the objective of the present study was to determine the association of BoLA-DRB3.2 alleles with tick resistance in cattle. The study was conducted on 231 F2 (Gyr x Holstein) animals that were artificially infested with 10,000 tick larvae. Log of tick count +1 was used as the dependent variable in a mixed animal model with allele substitution effects in addition to fixed effects of year and season at tick count, sex of calves, age of animal at tick count, hair type (short-straight, short-curl, long-straight, and long-curl), coat color (white, >75% white, 50- 75% white, and 25-50% white), and additive genetic, permanent environmental and residual effects as random. Females showed fewer ticks than males. Animals with short-straight hair were more resistant to tick infestation than animals with long-curl hair, and animals with whiter coat color also had fewer ticks. An association between BoLA alleles and lower tick number was found for alleles DRB3.2 *18, *20 and *27 at the 5% significance level. Also, one allele (DRB3.2*16) showed an association at the 10% level. Allele *27 was the most frequent in the population (30.7%), followed by alleles *16 (10.8%), *20 (8.7%) and *18 (2.4%). These results suggest that BoLA-DRB3.2 alleles could be used to help in the selection of animals resistant to tick infestation. However, further studies involving a larger population of cattle in combination with other BoLA genes may help to understand the mechanisms of resistance to parasites.

DGAT1 K232A polymorphism in Brazilian cattle breeds

Recent reports identified DGAT1 (EC 2.3.1.20) harboring a lysine to alanine substitution (K232A) as a candidate gene with a strong effect on milk production traits. Our objective was to estimate the frequency of the DGAT1 K232A polymorphism in the main Zebu and Taurine breeds in Brazil as well as in Zebu x Taurine crossbreds as a potential QTL for marker-assisted selection. Samples of 331 animals from the main Brazilian breeds, Nellore, Guzerat, Red Sindhi, Gyr, Holstein, and Gyr x Holstein F1 were genotyped for DGAT1 K232A polymorphism (A and K alleles) using the PCR-RFLP technique. The highest frequency of the A allele was found in the Holstein sample (73%) followed by Gyr x Holstein F1 (39%). Gyr and Red Sindhi showed low frequencies of A alleles (4 and 2.5%, respectively). The A allele was not found in the Nellore and Guzerat samples. Our results could be used to guide association studies between this locus and milk traits in these breeds.

Genetic trend for milk yield in Guzerat herds participating in progeny testing and MOET nucleus schemes

Genetic trends for 305-day milk yield (P305) in Brazilian Guzerat herds under selection were compared. Data from 4898 lactations of 3179 purebred and crossbred cows from various regions of Brazil were used. Milk yield was adjusted for mature age and the contemporary groups were defined as herd and calving year. Genetic parameters were estimated using the MTDFREML program. The model included the random effects of animals and permanent environment, and herd-calving year, calving season and genetic composition as fixed effects. Genetic trends were estimated by linear regression of weighted average estimated breeding values as a function of calving year. The average P305 was 2065 +/- 922 kg and the heritability was 0.23 +/- 0.03. The annual genetic trend in estimated breeding values of cows for P305 was 7.09 +/- 0.71 kg between 1987 and 2004, and 6.47 +/- 2.35 kg between 1997 and 2004. For cows born and raised in the multiple ovulation and embryo transfer (MOET) nucleus, this trend was 36.46 +/- 24.54 kg/year between 1997 and 2004, 183.14 +/- 47.94 kg/year between 1997 and 2000, and 9.13 +/- 19.19 kg/year between 2001 and 2004. An average inbreeding coefficient of 0.04 was found for inbred MOET cows in 2004. Increasing the size of the family and introducing new progenies changed reliabilities and predicted transmitting ability estimates of MOET sires. In conclusion, there was a positive genetic trend for milk yield in the MOET nucleus at low inbreeding coefficients due to the increased accuracy and estimated genetic merit, but no changes in the average milk yield were observed.

Genotyping BoLA-DRB3 alleles in Brazilian Dairy Gir cattle (Bos indicus) by temperature-gradient gel electrophoresis (TGGE) and direct sequencing

BoLA-DRB3 is a gene of the major histocompatibility complex (MHC) in cattle. The product of the BoLA-DRB3 gene is a beta chain of an MHC class II molecule, a glycoprotein expressed on the surface of antigen-presenting cells (APCs). Responses of CD4+ T lymphocytes to peptides are dependent on the presentation of peptide ligands bound to class II molecules on APCs. Genotyping of the BoLA-DRB3 gene is relatively complex due to the extensive polymorphism of this locus. Current techniques for assignment of genotypes are polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), direct sequencing of PCR products, cloning-sequencing, polymerase chain reaction using sequence-specific oligonucleotide probes (PCR-SSOP), and denaturant-gradient gel electrophoresis. These techniques are time-consuming, do not discriminate all possible alleles, or are not readily reproducible. The objective of this study was to genotype BoLA-DRB3 using temperature-gradient gel electrophoresis (TGGE) to separate alleles before sequencing. PCRs using 28 DNA samples from Gir Dairy cattle (a Brazilian breed of Bos indicus) were submitted to TGGE. New PCR products were generated from separated alleles, purified, and sequenced. Allele separation was possible in 21 out of 26 heterozygote samples (81%). Results indicate that two sequence reads (forward and reverse) were sufficient for accurate genotyping of BoLA-DRB3 alleles. Separation of alleles by TGGE provides high-throughput, reliable typing of BoLA-DRB3, which is critical in disease association studies in cattle.

Characterization of open reading frame-expressed sequence tags generated from Bos indicus and B. taurus mammary gland cDNA libraries

Sequence-based gene expression data are used to interpret results from functional genomic and proteomics studies. Although more than 300 000 bovine-expressed sequence tags (ESTs) are available in public databases, a more thorough and directed sampling of the expressed genome is needed to identify new transcripts and improve assembly and annotation of existing transcript sequences. Accordingly, we examined the utility of constructing cDNA libraries synthesized by arbitrarily primed RT-PCR of mRNA from tissues not well represented in the publicly available bovine EST database. A total of 33 cDNA libraries were constructed from healthy and infected mammary gland tissues of Brazilian Gir and Holstein cattle. This series of libraries was used to generate 6481 open reading frame-expressed sequence tags (ORESTES) that assembled into 1798 unique sequence elements of which, 1157 did not significantly match sequence assemblies available in the Bos taurus gene index. However, a total of 264 of these 1157 sequence elements aligned with mouse and human expressed sequences demonstrating that ORESTES is an effective resource for discovery of novel expressed sequences in cattle. Furthermore, comparison of the alignment position of bovine ORESTES-derived sequence elements to human gene reference sequences suggested that the priming events for cDNA synthesis more often occurred at the central portion of a transcript, which may have contributed to the relatively high rate of novel sequence discovery.

TGF-beta(3)-induced chondroitin sulphate proteoglycan mediates palatal shelf adhesion

In mammals, the adhesion and fusion of the palatal shelves are essential mechanisms in the development of the secondary palate. Failure of any of these processes leads to the formation of cleft palate. The mechanisms underlying palatal shelf adhesion are poorly understood, although the presence of filopodia on the apical surfaces of the superficial medial edge epithelial (MEE) cells seems to play an important role in the adhesion of the opposing MEE. We demonstrate here the appearance of chondroitin sulphate proteoglycan (CSPG) on the apical surface of MEE cells only immediately prior to contact between the palatal shelves. This apical CSPG has a functional role in palatal shelf adhesion, as either the alteration of CSPG synthesis by beta-D-Xyloside or its specific digestion by chondroitinase AC strikingly alters the in vitro adhesion of palatal shelves. We also demonstrate the absence of this apical CSPG in the clefted palates of transforming growth factor beta 3 (TGF-beta(3)) null mutant mice, and its induction, together with palatal shelf adhesion, when TGF-beta(3) is added to TGF-beta(3) null mutant palatal shelves in culture. When chick palatal shelves (that do not adherein vivo nor express TGF-beta(3), nor CSPG in the MEE) are cultured in vitro, they do not express CSPG and partially adhere, but when TGF-beta(3) is added to the media, they express CSPG and their adhesion increases strikingly. We therefore conclude that the expression of CSPG on the apical surface of MEE cells is a key factor in palatal shelf adhesion and that this expression is regulated by TGF-beta(3).

Distribution of bovine lymphocyte antigen (BoLA-DRB3) alleles in Brazilian dairy Gir cattle (Bos indicus)

Brazilian dairy Gir (Bos indicus) cattle are a tropical, well-adapted breed, for which no information on the major histocompatibility complex (MHC) is presently available. The second exon of the bovine lymphocyte antigen (BoLA-DRB3) was amplified by polymerase chain reaction (PCR) of DNA samples from 28 Brazilian dairy Gir cows. Two experimental genotyping approaches were used: direct sequencing of PCR gene products (PCR-DS) and sequencing of cloned PCR fragments (S-CLO). Results demonstrate the viability of both typing approaches. PCR-DS allowed typing of 39% of the animals while the remainder were genotyped by S-CLO. Seventeen BoLA-DRB3 alleles were assigned, including some that were only recently described for zebu cattle. Allelic frequencies ranged from 0.02 to 0.18. The most frequent alleles were *3601 (frequency = 0.18), *2201 (0.14) and *2101 (0.11).

Immune stimulating activity of two new chitosan containing adjuvant formulations

Recombinant proteins have potential as both human and veterinary vaccine antigens, but they are often weakly immunogenic and immunization with recombinant proteins may not elicit a significant immune response that recognizes the native protein. This report describes the immune stimulating activity of two new adjuvant formulations, a zinc-chitosan particle formulation designed to bind to histidine tagged recombinant proteins; and an emulsion formulation containing chitosan. BALB/c mice vaccinated with formulations comprising recombinant beta-human chorionic gonadotropin (betahCG) and each adjuvant had prolonged high titer antibodies that recognized both the recombinant betahCG and native hCG. betahCG is an established target for immunocontraceptive vaccines and a potential target for tumor immunotherapy. Isotype analysis of these antibodies revealed an IgG1 response in mice immunized with zinc-chitosan particles and a mixed IgG1, IgG2a and IgG2b response with the emulsion. These chitosan based adjuvant formulations were effective in sensitizing mice and guinea pigs for antigen specific DTH responses, indicating that these adjuvants stimulate both B and T lymphocytes. The ability of these adjuvants to stimulate significant responses with a poorly immunogenic recombinant protein suggests that they may have potential in developing vaccines based on synthetic peptides and subunit antigens.

Effectiveness of zona pellucida protein ZPB as an immunocontraceptive antigen

Immunization of female mammals with native zona pellucida (ZP) proteins is known to cause infertility. Since each human ZP protein is now available as a purified recombinant protein, is it possible to compare the immunocontraceptive potential of each ZP protein. A breeding study was conducted in cynomolgus monkeys (Macaca fasicularis) after immunization with recombinant human ZP (rhZP) proteins (ZPA, ZPB, ZPC) separately and in combinations. This study demonstrated that immunization with recombinant human ZPB (rhZPB) protein caused cynomolgus monkeys to become infertile for 9-35 months. A second study was conducted in baboons (Papio cynocephalus), which yielded a similar result. The baboons immunized with rhZPB became infertile for 9 to > 20 months. During the time of maximum antibody titre, some animals experienced disruption of the menstrual cycle, but eventually all of the animals resumed normal menstrual cycles. Control animals and animals immunized with other rhZP proteins all became pregnant before any of the rhZPB-treated animals. This is the first study in which a recombinant ZP protein has consistently induced infertility in a primate without permanent disruption of the normal menstrual cycle.

Effectiveness of zona pellucida protein ZPB as an immunocontraceptive antigen

Immunization of female mammals with native zona pellucida (ZP) proteins is known to cause infertility. Since each human ZP protein is now available as a purified recombinant protein, is it possible to compare the immunocontraceptive potential of each ZP protein. A breeding study was conducted in cynomolgus monkeys (Macaca fasicularis) after immunization with recombinant human ZP (rhZP) proteins (ZPA, ZPB, ZPC) separately and in combinations. This study demonstrated that immunization with recombinant human ZPB (rhZPB) protein caused cynomolgus monkeys to become infertile for 9-35 months. A second study was conducted in baboons (Papio cynocephalus), which yielded a similar result. The baboons immunized with rhZPB became infertile for 9 to > 20 months. During the time of maximum antibody titre, some animals experienced disruption of the menstrual cycle, but eventually all of the animals resumed normal menstrual cycles. Control animals and animals immunized with other rhZP proteins all became pregnant before any of the rhZPB-treated animals. This is the first study in which a recombinant ZP protein has consistently induced infertility in a primate without permanent disruption of the normal menstrual cycle.

Temporal alterations in mRNA levels for proteinases and inhibitors and their potential regulators in the healing medial collateral ligament

Wound healing in ligaments is a complex process which leads to functionally impaired scar tissue, even after extended time postinjury. To investigate the potential role of proteinases and inhibitors, as well as potential regulators of their expression, mRNA levels for collagenase, stromelysin, urokinase, PAI-1, and TIMPs 1 to 4 have been assessed by semiquantitative RT-PCR in RNA isolated from rabbit ligaments 3, 6, and 14 weeks postinjury. In addition, mRNA levels for IL-1, TNF, COX-2, and iNOS, potential regulators of proteinase/inhibitor expression, have been assessed. mRNA levels for the proteinases TIMP-1, -2, and -3 and PAI-1 were elevated early in scar tissue, but TIMP-4 mRNA levels exhibited a different pattern. In contrast, mRNA levels for the cytokines iNOS and COX-2 were either unchanged or depressed early after injury. The results indicate that alterations in mRNA levels for proteinases and inhibitors occurring early after injury are likely being influenced by factors other than IL-1, TNF, or products of COX-2 or iNOS.

Technetium-99m tetrofosmin scintigraphy to evaluate breast lesions

The aim of this study is to characterise benign from malignant breast lesions by using 99mTc-Tetrofosmin.

MATERIALS

Fifteen female patients with suspected breast lesions and ten normal controls underwent breast scintigraphy with 99mTc-Tetrofosmin. All patients had conventional mammography. Breast imaging begun 20 minutes after i.v. injection of 740 MBq 99mTc-Tetrofosmin. Patients were imaged in supine and prone position. Results of the 15 patients with suspected breast lesions, 13 showed breast uptake, and 6 of them had suspicious lesions on mammography. Surgery confirmed 10 carcinomas and 3 benign lesions. Two patients demonstrated no abnormal accumulation or suspicious findings in mammography. None of the normal controls had breast uptake or mammographic abnormalities. Our study has a sensibility of 100% and 60%, and a specificity of 80% and 100% in scintigraphy and mammography respectively.

CONCLUSION

Our findings suggest that 99m Tc-Tetrofosmin may play a role in evaluating breast masses and that can differentiate benign from malignant lesions.

Titanium metal release after posterior cervical spine plate placement in a canine model

The local tissue concentration of released titanium from Ti-6Al-4V posterior cervical spine plates in canines was determined using inductively coupled plasma atomic emission spectroscopy. The plates were also evaluated for percentage of surface area damage. The highest titanium levels (> 100 ppm dry weight) and most severe surface damage were associated with screw-plate interfaces. A model to explain the metal release mechanisms was proposed, consisting of a combination of fretting wear, diffusion through the passive oxide layer, and dissolution of this layer.

Evaluation of free or liposome-encapsulated ribavirin for antiviral therapy of experimentally induced feline infectious peritonitis

Ribavirin, either free in aqueous solution or incorporated into liposomes, was evaluated in 50 specific-pathogen-free kittens after experimental challenge exposure with feline infectious peritonitis virus (FIPV). Ribavirin was administered daily for 10 to 14 days at 16.5 mg kg-1 bodyweight given per os, intramuscularly or intravenously beginning 18 hours after kittens were challenge-exposed with FIPV. All kittens, including ribavirin-treated and untreated kittens, succumbed to FIP. Clinical signs of disease were more severe in the ribavirin-treated kittens and their mean survival times were shortened. The clinical efficacy of free ribavirin given intravenously at a reduced dosage (5.5 mg kg-1 bodyweight) was compared to that of ribavirin incorporated into lecithin-containing liposomes (5 mg kg-1) intravenously. Drugs were given once daily for three consecutive days of each week for three weeks, beginning 18 hours after virus challenge exposure. There was no significant difference either in survival rate or severity of disease between kittens given free ribavirin, liposomal ribavirin or saline only. Because of its intrinsic toxicity and low therapeutic index against FIPV and its marginal antiviral activities in vivo at maximal doses, ribavirin cannot presently be recommended as primary antiviral chemotherapy against FIP.

Detection of feline infectious peritonitis virus infection in cell cultures and peripheral blood mononuclear leukocytes of experimentally infected cats using a biotinylated cDNA probe

A dot blot hybridization assay, using a biotinylated cDNA probe, was able to detect feline infectious peritonitis virus (FIPV) RNA in Felis catus whole fetus (fcwf-4) cells infected with the FIPV isolates DF2, 79-1146, UCD1, and UCD2. The probe cross-hybridized in the dot blot assay with nucleic acid of a closely related feline coronavirus, feline enteric coronavirus (FEVC)-79-1683. To construct the probe, a 2.5 kilobase cDNA, prepared from FIPV-DF2 genomic RNA, was molecularly cloned. The recombinant cDNA clone was digested with the restriction endonuclease Rsa I, and an 870 basepair Rsa I fragment was isolated from vector DNA by agarose electrophoresis and glass-milk purification. This fragment was complementary to the 3' three fourths of the nucleocapsid gene. The hybridization probe was prepared by random primed labeling in the presence of biotin-11-dUTP. Using an avidin-alkaline phosphatase conjugate and chemiluminescent substrate detection system, virus could be detected in as few as 3000 infected cells. In an in vivo study, the probe was used to detect FIPV RNA in peripheral blood mononuclear leukocytes (PBML) isolated at various post-infection days (PID) from cats experimentally infected with the FIP-producing coronavirus isolate FIPV-79-1146 or FIPV-DF2. Viral RNA could be detected in as few as 12,000 PBML isolated from cats at PID 7 and in 50,000 PBML at PID 22. There was no consistent pattern, however, between hybridization results and prognosis or severity of disease at the time of sampling. Despite some cross-hybridization with FECV RNA, this probe should be useful for diagnosis of FIP, because cats infected with FECV most likely do not become viremic.

Physiological comparison of roller skating, treadmill running and ergometer cycling

This study was undertaken to determine the metabolic and cardiorespiratory differences between treadmill running, ergometer cycling and roller skating in top level roller skaters. The subjects performed 3 discontinuous graded tests until exhaustion. The protocol was established so that heart rate kinetics during exercise were similar in all the tests. Maximal oxygen uptake (VO2max), maximal heart rate and exercise time to exhaustion were higher during running (p < 0.05) than during cycling. Blood lactate during submaximal and maximal running exercise was significantly lower (p < 0.05) than during cycling or roller skating. There were no differences between cycling and roller skating in any of the variables studied. These results seem to suggest that, compared with running, VO2max during cycling is limited more by local muscle fatigue than by cardiac factors. The similar response found during roller skating and cycling supports the concept that cycloergometer testing is a valid simple laboratory test for testing physical fitness in top level roller skaters.

Applications of genetic engineering technology in feline medicine

Genetic engineering technology is a rapidly developing field that has almost unlimited potential for the production of safer and more effective vaccines, therapeutic proteins, and more specific and sensitive diagnostic reagents. Although applications in veterinary medicine of genetically engineered products are presently limited by availability of species-specific reagents, the use of recombinant DNA products is increasing. Because of the recent discovery of FIV and the relevance of FIV as an animal model for the study of human immunodeficiency virus, feline genetic research is gaining in importance. Research using FIV as a human AIDS model ideally will yield many new species-specific feline recombinant DNA products that have important applications in feline medicine and research.

Spontaneous pneumothorax in patients with the human immunodeficiency virus: study of eight cases

OBJECTIVE

To evaluate the risk factors and the natural history of spontaneous pneumothorax in patients with human immunodeficiency virus infection (HIV).

METHODS

We studied eight HIV infected patients with spontaneous pneumothorax. Variables assessed included sex, age, risk factor for HIV infection, use of Pneumocystis carinii pneumonia prophylaxis, total and CD4 positive lymphocyte count, previous history of Pneumocystis carinii pneumonia or pulmonary tuberculosis, chest X-ray film, presence of simultaneous opportunistic infection, partial pressure of oxygen in arterial blood gas determination and clinical outcome.

RESULTS

The patients were predominantly male and intravenous drug abusers. Mean age was 28 years (range: 21-44). Five patients had acquired immunodeficiency syndrome, 2 oral candidiasis and one asymptomatic HIV infection. Three had previously had Pneumocystis carinii pneumonia and six a concurrent opportunistic infection. No one was receiving aerosolized pentamidine prophylaxis. The pneumothorax was bilateral in two cases. Chest tube evacuation was required in seven, and six patients died. Only two patients without opportunistic infection were discharged.

CONCLUSIONS

We conclude that spontaneous pneumothorax is a serious problem with high mortality in patients with advanced human immunodeficiency virus infection. Previous or active Pneumocystis carinii pneumonia appear to be a risk factor for developing pneumothorax. It seems to be independent of aerosolized pentamidine use.

Age and Zebu-Holstein additive and heterotic effects on lactation performance and reproduction in Brazil

Data of 6482 lactations from 14 crossbred (Holstein x Zebu) herds in Brazil were used to study breed additive and heterosis effects for first, second, third, and first to fifth lactation milk yields, age at first calving, calving interval, and milk yield divided by calving interval, as well as the effect of age at calving on milk yield. Holstein additive expressed as deviation from Zebu and heterosis effects were highly significant for all traits. For each percentage of Holstein gene contribution an increase of 10.02, 12.02, 12.51, and 12.15 kg of milk were expected for first, second, third, and first to fifth lactation yields, respectively. Corresponding heterosis effects on those traits were 3.80, 3.39, 4.02, and 3.90 kg of milk for each percentage of heterozygosity. Replacement of pure Zebu genes by Holstein genes reduced age at first calving by 6 mo and shortened calving interval by 37 d. Holstein x Zebu heterotic effect decreased age at first calving by 2 mo and calving interval by 39 d. Holstein additive and heterosis effects for milk yield divided by calving interval were 3.4 and 1.3 kg of milk/d, respectively. Fitting breed additive and heterozygosity effects accounted for 99% of the genetic effects except for first to fifth lactation milk yield.

Evaluation and treatment of intraabdominal bilomas

In a 3-year period, 21 intraabdominal bilomas developed in 18 patients. Fifteen of the patients had a solitary biloma, and the other three patients each had two separate concurrent bilomas. The major cause of biloma formation was postoperative bile leakage from a bile duct after laparotomy done primarily for surgery on the gallbladder or liver. Maximal diameter of the bilomas in the transaxial plane ranged from 2 to 19 cm. Sixteen of the bilomas were in the right upper quadrant, and five were in the left upper quadrant. Two large right-sided collections extended caudally into the lower abdomen. The contours of the bilomas were configured by the diaphragm, mesenteries, liver, and other abdominal organs. On CT and sonography, the bilomas were invariably well demarcated, but most did not have an identifiable capsule. CT did demonstrate a thin rim on four bilomas and a thick rim on one. In 19 bile collections, the CT numbers were less than 20 H. The combination of the clinical history, the location, and the CT appearance of the lesion led to the correct diagnosis in each case. Percutaneous drainage was an effective form of therapy that often eliminated the need for surgical drainage.

Factors affecting calf livability for Holsteins

A total of 136,775 records from Holstein calvings was obtained from the National Association of Animal Breeders. Calf mortality (scored as dead at birth plus dead by 48 h) was greater for males (7.6%) than for females (5.6%). First parities of dams showed about two times as much calf mortality as later parities (10.5 versus 5.6%). Relationship was nonlinear between calf livability and size of calf, regardless of parity-of-dam and sex-of-calf effects. Dead calves averaged 1.2 days shorter gestation than live calves (279.6 days). Sex of calf, parity of dam, and linear and quadratic gestation length affected calf livability when the model also included sires. Percentage of calf mortality of progeny of individual sires ranged from 1 to 16% for sires with at least 60 progeny. Mixed model estimates of heritabilities of livability were 1.02% (when coded as 1-alive at 48 h, 2-dead at birth, and 3-dead within 48 h) and 1.54% (when coded as 1-alive, 2-dead by 48 h). Heritability decreased 26% when gestation length was ignored. Attempts to normalize scores did not improve estimates of heritability. Heritability for livability was small.

Genetic relationship between calf livability and calving difficulty of Holsteins

Multitrait procedure was used to investigate the genetic relationship between calf livability and calving difficulty of Holsteins. The genetic correlation between calf livability and calving difficulty was .66. Heritabilities were .9% for calf livability and 4.1% for calving difficulty. The product-moment correlation (.4) between sires' transmitting abilities estimated separately for livability and dystocia, with properties of Best Linear Unbiased Predicator, underestimated the genetic correlation (.66). The correlated response of calf livability is expected to be 41% greater when selection is for dystocia than is expected from direct selection on calf livability.

Extrinsic allergic alveolitis caused by pigeon breeding at a high altitude (2,240 meters). Hemodynamic behavior of pulmonary circulation

The hemodynamic characteristics of the pulmonary circulation were examined in 10 patients with proved extrinsic allergic alveolitis caused by pigeons (EAA-P) raised at a high altitude. All patients had lung biopsies that showed an interstitial inflammatory response with vascular lesions. At rest, all patients had mean pulmonary pressures (PAP) greater than 16 mmHg; the average PAP was 22 +/- 12 mmHg for the whole group. Pulmonary vascular resistance was high and the mean for the whole group was 225 +/- 25 d.s.cm-5. The pulmonary artery diastolic-pulmonary wedge pressure (PAd-PWP) difference was elevated and averaged 8.5 +/- 2 mmHg. All patients were hypoxemic with elevated AaDO2. With exercise, both PAP and PAd-PWP increased abnormally. While breathing oxygen (FIO2, 99.6%) PAP decreased an average of 7 mmHg (p less than 0.05) and PAd-PWP decreased an average of 5 mmHg (p less than 0.05) without a significant change in PWP. The calculated compliance of the elastic pulmonary arteries in EAA-P was not different from that in normal subjects. Alveolar hypoxia produced mainly by EAA-P and presumably enhanced by living at a high altitude appeared to be the factors in the genesis of pulmonary hypertension, because pulmonary artery diastolic pressure and PAd-PWP difference were correlated with arterial oxygen saturation.