Poverty and the wellbeing of children with sickle cell disease: The mediating role of parenting stress

BACKGROUND

Living in poverty in the midst of caring for a child with sickle cell disease (SCD) presents with challenges that may be overwhelming for caregivers. Prior research has shown a relationship between poverty and poor outcomes in children; however, no study has investigated the mediating role of parenting stress on health-related quality of life (HRQOL) for such children.

PROCEDURE

A total of 150 patients, ages 8-17 years and their parents, were enrolled and completed measures of parenting stress (caregivers) and HRQOL (patients). Caregivers also completed a demographic information questionnaire, which was used to determine poverty status. The Sobel test was used to analyze the association between poverty and HRQOL by way of parenting stress.

RESULTS

The series of linear regression results show poverty was a significant predictor for decreased HRQOL (B = -7.01, p = .05) among pediatric patients with SCD. Moreover, the regression coefficient measuring the indirect effect of the model measuring the mediating role of parenting stress was statistically significant (B = -1.05, p = .05).

CONCLUSION

The current study found an association between poverty status and HRQOL scores by way of parenting stress. Findings highlight the need for appropriate resource allocation to caregivers in addition to pediatric patients living with SCD.

Challenges and opportunities of remote public involvement and community engagement during a pandemic: refining the MapMe childhood healthy weight intervention

AIMS

Including parents and other stakeholders in the development of interventions to address the sensitive public health issues such as childhood obesity, through public involvement is critical. However, the Covid-19 pandemic has created a challenge for public involvement and engagement activities (PICE). The aim of this paper is to describe the process and challenges of setting up, maintaining, evaluating, and recording impact of three public and stakeholder groups via remote methods in the context of the MapMe2 study during the Covid-19 pandemic. Parental reaction to result letters received as part of the National Child Measurement Programme (NCMP) informing parents of their child's overweight status is often one of hostility or disbelief. As a result, parents often do not act on these letters to address child overweight. The MapMe2 study is working in collaboration with the NCMP and local authorities, building on previous work (MapMe) and aims to support parents of primary school-aged children to recognise and maintain a healthy weight in their child. The existing MapMe Intervention includes an enhanced NCMP child weight result letter, supplemented with Body Image Scales (BIS), and an intervention website with material to support healthy eating, physical activity, and signposting supporting information. The intervention was to be refined and the evaluation informed with PICE input.

METHODS

Covid-19 restrictions meant that planned face-to-face PICE methods had to be altered with all recruitment, all correspondence, and activities taking place remotely. A Parent Involvement Panel (PIP), a child panel, and an expert panel were established. Several adaptations were made to accommodate a new way of involving the public in research.

RESULTS/CONCLUSIONS

Working remotely created many challenges and was a learning experience for all involved. However, an active group was successfully established. Using continuous assessment and evaluation methods, we were able to demonstrate successful involvement and engagement in the refinement of the MapMe2 study. Through the sharing of PICE methods practice, this paper adds to the literature, the value of partnership working.

Agreement in the reporting of General Practitioner requested musculoskeletal radiographs: Reporting radiographers and consultant radiologists compared with an index radiologist

INTRODUCTION

This study assessed the inter-observer agreement of reporting radiographers and consultant radiologists compared with an index radiologist when reporting General Practitioner (GP) requested musculoskeletal radiographs. The potential effect of discordant reports on patient management and outcome was also examined.

METHODS

Three reporting radiographers, three consultant radiologists and an index radiologist reported on a retrospective randomised sample of 219 GP requested musculoskeletal radiographs, in conditions simulating clinical practice. A speciality doctor in radiology compared the observers' reports with the index radiologist report for agreement and assessed whether any discordance between reports was clinically important.

RESULTS

Overall agreement with the index radiologist was 47.0% (95% CI, 40.5-53.6) and 51.6% (95% CI, 45.0-58.1) for the consultant radiologists and reporting radiographers, respectively. The results for the appendicular and axial skeleton were 48.6% (95% CI, 41.3-55.9) and 40.9% (95% CI, 27.7-55.6) for the radiologists, and 52.6% (95% CI, 45.2-59.8) and 47.7% (95% CI, 33.8-62.1) for the radiographers, respectively. The difference in overall observer agreement between the two professional groups with the index radiologist was not statistically significant (p = 0.34). Discordance with the index radiologist's reports was judged to be clinically important in less than 10% of the observer's reports.

CONCLUSION

Reporting radiographers and consultant radiologists demonstrate similar levels of concordance with an index radiologist when reporting GP requested musculoskeletal radiographs.

IMPLICATIONS FOR PRACTICE

These findings contribute to the wider evidence base that selected radiographers with appropriate postgraduate education and training are proficient to report on musculoskeletal radiographs, irrespective of referral source.

Factors associated with willingness to provide biospecimens for genetics research among African American cancer survivors

This study evaluated factors associated with willingness to provide biospecimens for cancer genetic research among African American cancer survivors. A total of 200 African American adults diagnosed with breast, colon, and/or prostate cancers completed a self-administered survey. Family history information, beliefs about cancer research, cancer genetics and disparities knowledge, willingness to provide a biospecimen, and demographics were obtained. Chi-square, independent samples t tests, and logistic regression analyses were performed. Overall, 79% of this sample was willing to provide a biospecimen for cancer genetics research. Independent associations of willingness to provide a biospecimen existed among demographics (males (p = 0.041)), those who believed in the importance of genetic causes of cancer (p < 0.001), individuals who believe it is important to participate in genetics research (p < 0.001), and those who indicated they would participate in genetics research to help future generations (p = 0.026). Overall, 12.5-56% of participants demonstrated some level of genetics and cancer disparities. This study identified factors that may be incorporated into future research interventions to engage the African American cancer population in cancer genetics biobanking research.

Impact of a multicomponent screening, brief intervention, and referral to treatment (SBIRT) training curriculum on a medical residency program

BACKGROUND

Substance-related disorders are a growing problem in the United States. The patient-provider setting can serve as a crucial environment to detect and prevent at-risk substance use. Screening, brief intervention, and referral to treatment (SBIRT) is an integrated approach to deliver early intervention and treatment services for persons who have or are at risk for substance-related disorders. SBIRT training components can include online modules, in-person instruction, practical experience, and clinical skills assessment. This paper will evaluate the impact of multiple modes of training on acquisition of SBIRT skills as observed in a clinical skills assessment.

METHODS

Residents were part of an SBIRT training program, from 2009 through 2013, consisting of lecture, role-play, online modules, patient encounters, and clinical skills assessment (CSA). Differences were assessed across satisfactory and unsatisfactory CSA performance.

RESULTS

Seventy percent of the residents satisfactorily completed CSA. Demographics, type of components completed, and number of components completed were similar among residents who demonstrated satisfactory clinical skills compared with those who did not. All components of the training program were accepted equally across specialties and resident matriculation cohorts.

CONCLUSION

The authors conclude that the components employed in SBIRT training do not have to be numerous or of a particular mode of training in order to see observable demonstration of SBIRT skills among medical residents. Thus, residency educators who have limited time or resources may utilize as few as 1 mode of training to effectually disseminate SBIRT skills among health care providers. As SBIRT continues to evolve as a promising tool to address at-risk substance-related disorders, it is critical to train medical residents and other health professionals.

Genetic testing for the susceptibility to alcohol dependence: interest and concerns in an African American population

BACKGROUND

The search to identify genes for the susceptibility to alcohol dependence (AD) is generating interest for genetic risk assessment. The purpose of this study is to examine the level of interest and concerns for genetic testing for susceptibility to AD.

METHODS

Three hundred four African American adults were recruited through public advertisement. All participants were administered the Genetic Psycho-Social Implication (GPSI) questionnaire, which surveyed their interests in hypothetical genetic testing for AD, as well as their perception of ethical and legal concerns.

RESULTS

Over 85% of participants were interested in susceptibility genetic testing; however, persons with higher education (p=0.002) and income (p=0.008) were less willing to receive testing. Perception of AD as a deadly disease (48.60%) and wanting to know for their children (47.90%) were the strongest reasons for interest in testing. Among those not interested in testing, the belief that they were currently acting to lower their risk was the most prevalent. The most widely expressed concern in the entire sample was the accuracy of testing (35.50%). Other notable concerns, such as issues with the method of testing, side effects of venipuncture, falsely reassuring results, and lack of guidelines on "what to do next" following test results, were significantly associated with willingness to receive testing.

CONCLUSION

Although an overwhelming majority of participants expressed an interest in genetic testing for AD, there is an understandable high level of methodological and ethical concerns. Such information should form the basis of policies to guide future genetic testing of AD.

Screening, brief intervention, and referral to treatment: public health training for primary care

OBJECTIVES

The purpose of this study was to elucidate changes in attitudes, experiences, readiness, and confidence levels of medical residents to perform screening, brief intervention, and referral to treatment (SBIRT) and factors that moderate these changes.

METHODS

A cohort of 121 medical residents received an educational intervention. Self-reported experience, readiness, attitude, and confidence toward SBIRT-related skills were measured at baseline and at follow-up. Analyses were conducted to evaluate the effects of medical specialization.

RESULTS

The intervention significantly increased experience (P<.001), attitude (P<.05), readiness (P<.001), and confidence (P<.001). Residents were more likely to report that their involvement influenced patients' substance use. However, experience applying SBIRT skills varied by country of birth, specialty, and baseline scores.

CONCLUSIONS

This study suggested that SBIRT training was an effective educational tool that increased residents' sense of responsibility. However, application of skills might differ by specialization and other variables. Future studies are needed to explore and evaluate SBIRT knowledge obtained, within the context of cultural awareness and clinical skills.

Heritability of level of response and association with recent drinking history in nonalcohol-dependent drinkers

BACKGROUND

Level of response (LR) to alcohol has been shown to be associated with the risk of developing alcohol dependence and can be measured using the self-rating of the effects of alcohol (SRE) questionnaire. This study examined the heritability of the SRE-measured LR and the relationship between LR and recent alcohol drinking history (RDH) in a predominantly African American nonalcohol-dependent population.

METHODS

This was a sibling study of 101 social drinkers aged 21 to 35 years recruited from the Washington, DC metropolitan area. Participants were administered the SRE to assess LR and the timeline followback (TLFB) to assess RDH. The indices of SRE used were total SRE score (SRTT), early drinking SRE score (SRED), regular drinking SRE score (SRRD), and heavy drinking SRE score (SRHD). Pearson's product-moment correlation and linear regression were used to analyze SRE indices and RDH variables (quantity and drinks per drinking occasion). Heritability analysis was conducted using Sequential Oligogenic Linkage Analysis Routines (SOLAR) software with SRE indices as traits of interest.

RESULTS

There was a significant relationship between SRE and RDH measures. Drinks per drinking day, maximum drinks, and quantity of drinks were significantly associated with SRTT, SRHD, and SRRD (all p < 0.05). SRTT showed significant heritability (h(2) = 0.67, p = 0.025), however, the SRE subindices (SRED, SRRD, SRHD) were not significantly heritable. Analysis performed in the subset consisting of only African Americans (n = 86) showed similar trends.

CONCLUSIONS

LR, as measured by the SRE, is associated with RDH. The high level of heritability of the SRE total score suggests that genetics accounts for a significant proportion of the variation in the LR to alcohol in social drinkers.

Household characteristics and mite allergen levels in Manchester,UK

BACKGROUND

Mite allergen levels vary enormously between different homes in the same geographical area. No large scale studies of mite levels in Manchester homes has been conducted to identify factors associated with higher levels.

OBJECTIVES

To quantify exposure to mite allergens and to identify characteristics associated with higher Der p 1 levels in a large sample of homes in Manchester, UK.

METHODS

Der p 1 was measured in dust from the living room floor, sofa, bedroom floor and mattress in 564 homes. Data on household characteristics were collected by administering a questionnaire. Univariate and multivariate analyses were performed to identify household characteristics associated with higher mite allergen levels.

RESULTS

Der p 1 levels were highest in the mattress (GM 1.19 microg/g, 95% CI 0.98-1.45, P < 0.001). Two-thirds of homes contained Der p 1 levels > 2 microg/g in at least one dust reservoir, and 40.3% contained Der p 1 greater than 10 microg/g. There was a large range in Der p 1 levels between homes (> 10(3)-fold). Damp and condensation were common findings in homes. In the multivariate analyses, factors associated with higher Der p 1 levels in more than one dust reservoir were older homes, older living room carpets, damp, condensation and mixed glazing. Older mattresses were associated with higher mite allergen levels in the mattress where the age of the mattress was recorded. Twenty-four homes contained no detectable mite allergen, six of which reported damp.

CONCLUSIONS

Mite allergen levels are high enough in two of every three homes to be associated with an increase in the risk of sensitization to mite. Factors such as older homes, carpets and mattresses, damp and condensation are associated with higher mite allergen. However, mite allergen levels are occasionally unpredictably very low in homes with risk factors for high levels.

A common oocyst surface antigen of Cryptosporidium recognized by monoclonal antibodies

Two hybridoma clones, CMYL3 and CMYL30, were generated by immunizing Balb/c mice with excysted oocysts of Cryptosporidium muris. Both clones secreted monoclonal antibodies against an oocyst-wall antigen with apparent molecular mass of 250 kDa (called CM250) from C. muris and C. parvum. The epitope appeared to be periodate-sensitive, suggesting the involvement of a carbohydrate moiety. Immunofluorescence and confocal microscopy on purified oocysts and infected mouse tissues revealed staining confined to the oocyst wall of both Cryptosporidium species. Immunogold labeling further revealed the presence of the CM250 antigen in electron-dense vesicles and cytoplasm of developing macrogametocytes, and ultimately localized to the oocyst wall of mature oocysts. Both antibodies cross-reacted with C. serpentis oocysts but did not recognize the other enteropathogenic protozoans Giardia muris, Eimeria falciformis and E. nischulz. These antibodies may be valuable tools for the analysis of oocyst-wall formation in Cryptosporidium and characterization of the common antigen.

Lymphoproliferative responses in cord blood and at one year: no evidence for the effect of in utero exposure to dust mite allergens

BACKGROUND

Maternal allergen exposure beyond the 22nd week of pregnancy may be important in foetal T cell priming. Allergen-specific cord blood mononuclear cell (CBMC) immunoproliferative responses without corresponding bacterial antigen responses (tetanus toxoid), have been suggested as evidence of in utero sensitization.

OBJECTIVES

To investigate the relationship between lymphoproliferative responses at birth and at 1 year with maternal and 1-year infants house dust mite allergen exposure.

METHODS

Home visits and dust sampling were performed by the 20th week of pregnancy, immediately after birth, and then at 1 years of age. Der p 1 was assayed using a two-site immunometric ELISA. CBMC immunoproliferative responses (AIM V serum-free medium; 1 x 105 cells/well) were measured for 225 neonates (171 had a high risk of atopy (HR)--both parents skin test positive; 59 had a low risk of atopy (LR) - both parents skin test negative, no history of atopy) by 3H-Thymidine (1microCi/well) incorporation after stimulation in primary culture with phytohaemagglutinin (PHA) (1 microg/mL), house dust mite [HDM] extract (30 microg/mL), immunopurified Der p 1 (30 microg/mL), Tetanus toxoid (TT) (aluma free, 30 Lf/mL) or vehicle. Blood was collected from 144 infants at the age of 1 years and stimulated proliferative responses were assessed using the same procedure.

RESULTS

PHA-stimulated lymphoproliferative response was significantly lower in HR compared to LR neonates (mean difference 38%, 95% CI 15%-54%; P = 0.003); significantly lower proportion of positive CBMC responses to HDM occurred in LR than in HR neonates (30.4% vs. 46.6%; P = 0.034). There was no relationship between Der p 1 levels in maternal bed and CBMC immunoproliferative responses, despite the 21 000-fold range of maternal Der p 1 exposure. No significant differences in magnitude, or in proportion of positive responses to any stimulant were observed between the neonates at low, medium or high tertile of allergen exposure. Immunoproliferative responses at birth were not predictive of 1-year PBMC responses. There was no relationship between maternal allergen exposure in pregnancy and 1-year PBMC proliferative responses. However, the proportion of positive proliferative responses at 1 years significantly increased with increasing infant Der p 1 exposure at 1 years.

CONCLUSION

These results indicate that the magnitude of immunoproliferative responses are unrelated to maternal mite allergen exposure and cannot be used as evidence for in utero sensitization to inhalant allergens. The immunoproliferative responses at 1 year seem to shift away from the genetically influenced responses at birth towards responses to specific stimulants which correlate with environmental exposure to those specific stimulants. These data support the concept of sensitization to inhalant allergens occurring in early life, but not in utero.

Urinary bladder hyporeflexia and reduced pain-related behaviour in P2X3-deficient mice

Extracellular ATP is implicated in numerous sensory processes ranging from the response to pain to the regulation of motility in visceral organs. The ATP receptor P2X3 is selectively expressed on small diameter sensory neurons, supporting this hypothesis. Here we show that mice deficient in P2X3 lose the rapidly desensitizing ATP-induced currents in dorsal root ganglion neurons. P2X3 deficiency also causes a reduction in the sustained ATP-induced currents in nodose ganglion neurons. P2X3-null mice have reduced pain-related behaviour in response to injection of ATP and formalin. Significantly, P2X3-null mice exhibit a marked urinary bladder hyporeflexia, characterized by decreased voiding frequency and increased bladder capacity, but normal bladder pressures. Immunohistochemical studies localize P2X3 to nerve fibres innervating the urinary bladder of wild-type mice, and show that loss of P2X3 does not alter sensory neuron innervation density. Thus, P2X3 is critical for peripheral pain responses and afferent pathways controlling urinary bladder volume reflexes. Antagonists to P2X3 may therefore have therapeutic potential in the treatment of disorders of urine storage and voiding such as overactive bladder.

The effect of dry heat on mite, cat, and dog allergens

BACKGROUND

Various techniques have been tried in an attempt to reduce allergen levels in homes. This study investigated the effect of dry heat on mite, cat, and dog allergens.

METHODS

Samples (50 mg) of Dermatophagoides pteronyssinus and D. farinae cultures, and of house dust rich in the major cat and dog allergens Fel d 1 and Can f 1 were heated for 5, 10, 15, 30, and 60 min at 60 degrees, 80 degrees, 100 degrees, 120 degrees, and 140 degrees C. Control samples remained at room temperature. Extracts were assayed with the appropriate two-site mono- or mono/polyclonal sandwich ELISA.

RESULTS

For Der p 1, the breakdown was proportional to temperature and heating time; after 30 min at 120 degrees C, allergen levels were reduced to < 1% of control. Der p 2 was more heat stable, requiring 140 degrees C for 30-60 min to achieve > 99% reduction. D. farinae groups 1 and 2 allergens showed results similar to those obtained with D. pteronyssinus. In contrast, Can f 1 and Fel d 1 were considerably more thermostable, with 50% and 70%, respectively, of allergen remaining after 60 min at 140 degrees C.

CONCLUSIONS

The effect of dry heat on allergens increased with increasing time and temperature, cat and dog allergens demonstrating greater heat resistance than mite allergens. Dry heating methods may represent an alternative technique for removal of mite allergens; however, the greater stability of Fel d 1 and Can f 1 suggests that this procedure may not be appropriate for pet allergens.

The role of alternative splicing of the adhesion molecule, CD44, in lymphoid malignancy

AIM

To investigate the expression of CD44 isoforms containing variant exon 6 (v6) in a well characterised cohort of patients with non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukaemia (CLL), and to correlate this with phenotype and disease course.

METHODS

Cryostat sections of OCT embedded diagnostic nodal material from NHL patients and cryopreserved mononuclear preparations from CLL patients were used as sources of RNA. After reverse transcription, PCR was carried out with amplimers positioned at either side of the variant exon insertion site to amplify all possible CD44 isoforms. Those isoforms containing v6 were identified after Southern blotting and hybridisation with a radiolabelled oligonucleotide.

RESULTS

Of 32 NHL samples analysed, 16 did not express CD44 isoforms containing v6, six expressed an isoform containing exon v6 alone, and 10 expressed v6 long isoforms which contained exon v6 in addition to other variant exons. These data did not correlate with lymphoma classification, disease staging, or the presence or absence of extranodal disease. However, those patients expressing v6 long CD44 isoforms had a worse overall survival than those that did not. The plateau of the survival curves was 50% compared with 82%. No v6 long isoforms were detected in the 21 CLL samples investigated.

CONCLUSIONS

The expression of v6 long CD44 isoforms is associated with aggressive disease in NHL, independent of grade, stage, or presence of extranodal disease.

Identification, characterization and expression of Toxocara canis nematode polyprotein allergen TBA-1

We have cloned the cDNA of TBA-1, the Nematode polyprotein allergen (NPA) of Toxocara canis and found it to be most similar to ABA-1, the Ascaris NPA, on the basis of amino acid sequence. We could study the antigenic properties of an E-coli synthesized fusion protein prepared with the cloned gene since no glycosylation site was expected from the deduced amino acid sequence. Although no IgE responses to TBA-1 were detected, recombinant TBA-1 was differently recognized by serum IgG antibodies when the recombinant TBA-1 was directly adsorbed vs when immobilized via a streptavidin linkage on polystyrene microtitre wells. One group of sera recognized TBA-1 directly immobilized while the second only recognized TBA-1 immobilized via streptavidin linkage. The former were from rodents immunized with a Toxocara sp. adult worm extract while the latter were obtained from rodents infected with T. canis larva or immunized with a Anisakis simplex L3 larval extract. These observations suggest that the two in vivo forms of TBA-1 are expressed, but during different stages of the parasite's life cycle.

OCT embedded sections of pathological specimens as a source of high quality RNA for reverse transcriptase/polymerase chain reaction

OCT embedded cryostat sections of stored pathological specimens of non-Hodgkin's lymphoma were used to provide RNA. After reverse transcription to produce cDNA, the polymerase chain reaction was performed with primers for standard and variant forms of the CD44 molecule. Using Southern transfer and hybridisation with a probe specific for exon 4 of the CD44 gene, both standard and variant forms were visualised by autoradiography. This method was shown to be applicable to other gene products by using primers specific for the abl and bcr genes. This technique permits retrospective analysis of RNA from small amounts of stored pathological samples.

Targeting gene expression to the vascular wall in transgenic mice using the murine preproendothelin-1 promoter

To develop a system for overexpressing genes in the vascular wall, we created transgenic mice using the reporter gene luciferase and the murine preproendothelin-1 promoter. In vitro analysis suggested that the murine 5'-flanking region contained endothelial-specific elements in a 5.9-kb fragment. Five transgenic mice colonies established from independent founders all exhibited the highest level of luciferase activity in the aorta with up to 8,540 light units per microgram of protein. Immunohistochemistry with anti-luciferase antisera revealed high levels of expression in the endothelial cells of both large and small arteries and lower levels of expression in veins and capillaries. Significant expression was also seen in arterial smooth muscle cells and in select epithelial surfaces which is consistent with the known distribution of endothelin-1 in mammals. The further demonstrate the targeting capability of this system, we overexpressed the lipid-peroxidating enzyme, human 15-lipoxygenase, in the vessel wall of transgenic mice. As with luciferase, expression of active enzyme and immunohistochemical localization in vascular cells were documented in transgenic animals. Hence, this new system can be used to direct expression of molecules to the vascular wall for the purpose of examining the biological significance of either overexpression or inhibition of select proteins.

Molecular heterogeneity of variant Philadelphia translocations in childhood acute lymphoblastic leukaemia

In acute lymphoblastic leukemia (ALL), it is unclear whether variant Philadelphia (Ph) translocations have the same molecular and clinical implications as the classical translocation. Two children with Ph+ ALL with variant translocations are described. One, in whom cytogenetic remission was not achieved, had evidence of translocation of c-abl to chromosome 22, rearrangement of minor breakpoint cluster region (mBCR) and expression of hybrid bcr/abl transcripts. In the other case, no gene rearrangement was found and complete remission was achieved. Variant Ph translocations in childhood ALL are heterogeneous at the molecular level. Molecular studies coupled with observations of clinical outcome are needed in larger numbers of such children to determine whether poor clinical response correlates with bcr/abl involvement and to allow planning of appropriate therapeutic strategies.

Evaluation of a method of ureteroneocystostomy in cats

Renal transplantation is a successful treatment for terminal renal failure in cats. Ureteral obstruction at the bladder wall or stoma has been a technical complication encountered in approximately 50% of clinical transplants. The small (0.4 mm) diameter of the feline ureter makes standard techniques described for ureteroneocystostomy unsatisfactory for cats. In this study, we used microsurgical techniques to oppose ureteral mucosa to intact bladder mucosa in an attempt to form a stricture-free stoma. In each of 5 anatomically normal cats, 1 ureter was microsurgically implanted in the bladder. Ultrasonographic examination of the kidneys, ureters, and bladder was performed twice weekly for 8 weeks. Excretory urography was performed at postoperative weeks 1, 2, 4, 8, and 12. Biopsy specimens were taken from the kidney on the surgically treated side 4 weeks after surgery. At 12 weeks, the kidney, ureter, and ureterovesical junction from the treated side were removed and submitted for histologic evaluation. At 1 week, all cats had enlargement of the kidney, renal pelvis, and ureteral lumen on the treated side. This enlargement gradually decreased, and by week 8, there was no difference in comparison with the control side. Ureteroneocystostomy that requires tunneling of the ureter through the bladder wall may result in hydroureter and hydronephrosis, which may resolve. Recognition of these changes may prevent unwarranted surgical intervention in cases of suspected obstruction. The technique described in this study has been used in 15 cats receiving renal allografts. None required surgical correction of ureteral obstruction.

Establishment and partial characterization of a radiation-induced canine monocytic leukemic cell line (RK9ML-1)

A myeloid leukemic cell line, designated RK9ML-1, was established from a dog with acute radiation-induced monocytic leukemia. Based on cytochemical stains which reacted positively only with nonspecific esterase, morphological and ultrastructural characteristics which indicated the presence of phagocytic vacuoles and lysosomal bodies, and cell surface properties which indicated the presence of Fc receptors, all the findings support that RK9ML-1 is of monocytic lineage. Chromosomal analysis of the cell line indicated the cells to be hypodiploid with acrocentric autosomes characteristic of canine cells.

Transplantation of DLA-compatible and incompatible fetal liver hematopoietic cells in dogs

Requirements for sustained engraftment of fetal liver hematopoietic stem cells were evaluated in 45 dogs. Pretransplant preparative treatment with total-body irradiation, 14.7 Gy, permitted engraftment of DLA-compatible fetal liver cells. Radiation alone was inadequate in DLA-haploidentical or DLA-mismatched transplants; none of 5 dogs had engraftment. Addition of cyclosporine facilitated engraftment. The combination of 14.7 or 16.1 Gy total-body irradiation (TBI) and cyclosporine allowed engraftment in 15 of 19 (78%) dogs receiving DLA-histoincompatible grafts and 11 Gy TBI plus cyclosporine allowed engraftment in 4 of 10 dogs. Restoration of granulopoiesis and thrombopoiesis was rapid; recovery of lymphocytes was relatively delayed, especially in recipients of incompatible fetal liver cells. Cumulative one-year survival was decreased in recipients of incompatible grafts due to early posttransplant infections. These data suggest that fetal liver transplantation is a potential approach in patients who lack an HLA-identical donor for bone marrow transplantation.

Sustained recovery of hematopoiesis and immunity following transplantation of fetal liver cells in dogs

We studied the ability of fetal liver cells to reconstitute hematopoiesis and immunity in lethally irradiated dogs. Engraftment and sustained lymphoid and hematopoietic recovery was achieved when the recipients received a preparative regime of high-dose total body irradiation (TBI) alone followed by transplantation of DLA-identical fetal liver. The combination of high-dose TBI and cyclosporine allowed engraftment in DLA-mismatched fetal liver transplants. Typical features of graft-versus-host disease (GvHD) did not occur although autoimmune-like syndromes (myasthenia gravis, immune thrombocytopenia) were observed in some recipients. Hematopoietic recovery was rapid and complete. Recovery of T- and B-lymphocyte function was comparatively delayed, but sufficient to prevent opportunistic infections after the initial 3 months post transplant. These data indicate that cells from a single fetal liver can reconstitute hematopoiesis and immunity in DLA-mismatched recipients and suggest that human fetal liver cell transplantation may be an effective source of stem cells for patients who lack an HLA-identical donor for bone marrow transplantation.

Growth of human malaria parasites in biotinylated erythrocytes

The adaptation of the biotin-avidin system for the analysis of membrane pathobiology in Plasmodium falciparum malaria is described. Biotin was linked covalently via the succinimide ester derivative (biotinyl-N-hydroxysuccinimide ester, BNHS) to intact human erythrocytes, prior to inoculation and in vitro cultivation of falciparum parasites. Growth experiments indicated that incubation concentrations of less than 1.0 mg BNHS/1.0 ml erythrocyte packed cell volume could yield biotinylated erythrocytes capable of sustaining parasite growth at levels comparable to control cultures. Using a synthesized [14C]BNHS compound at optimal incubation concentration, it was determined that 1.32 X 10(-4) mmol [14C]BNHS were bound per 1.0 mg of erythrocyte stromal protein. In addition, analysis of [14C]biotinylated red blood cell ghost preparations by polyacrylamide gel electrophoresis demonstrated that band 3 (a heterogeneous glycoprotein) was the principal site of membrane labeling. Approximately 77% of total membrane-associated [14C]BNHS was localized to this polypeptide. The unique properties of the specific, ligand-protein interaction of the biotin-avidin complex suggest that the biotinylation procedure described in this report will provide a useful analytical tool in host cell-plasmodial parasite, membrane studies.