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Purpose: The purpose of this study was to examine T cell development in rat lacrimal glands, determine whether the thymus is the source of immature T cells in this tissue and compare lacrimal gland T lymphocytes with other T cell subpopulations., Methods: Mononuclear cells were isolated from lacrimal glands of normal or thymectomized female Fischer 344 rats and stained for flow cytometric analysis., Results: The lacrimal gland T lymphocyte population included large percentages of cells with an activated phenotype and also subpopulations of immature, naive and memory T cells. The numbers of immature (Thy-1(+)) lacrimal gland T cells were unchanged following short-term adult thymectomy. In comparison, spleen had large percentages of naive T cells, only a small subpopulation of activated T cells, and similar percentages of immature (Thy-1(+)) T cells, which were nearly eliminated after thymectomy. Lacrimal gland T cells had small subpopulations of TCRgammadelta(+) and CD8alphaalpha( +) T cells, a large subpopulation of NKT cells and many integrin alphaEbeta7( +) T cells., Conclusions: Lacrimal gland T cells are composed of a variety of subpopulations whose composition is distinct from splenocytes. The marked reduction of immature splenic T cell percentages eleven days after adult thymectomy indicates that these cells were mostly derived from thymic precursors. In contrast, the unchanged percentages of immature lacrimal gland T cells following thymectomy indicate that they may have an extrathymic source. These studies provide a foundation for further investigation into the cellular basis of lacrimal gland immunobiology.

Campylobacter species, primarily Campylobacter jejuni and Campylobacter coli, are regarded as a major cause of human gastrointestinal disease, commonly acquired by eating undercooked chicken. We describe a PCR-ELISA for the detection of Campylobacter species and the discrimination of C. jejuni and C. coli in poultry samples. The PCR assay targets the 16S/23S ribosomal RNA intergenic spacer region of Campylobacter species with DNA oligonucleotide probes designed for the specific detection of C. jejuni, C. coli, and Campylobacter species immobilized on Nucleo-Link wells and hybridized to PCR products modified with a 5' biotin moiety. The limit of detection of the PCR-ELISA was 100-300 fg (40-120 bacterial cells) for C. jejuni and C. coli with their respective species-specific oligonucleotide probes and 10 fg (4 bacterial cells) with the Campylobacter genus-specific probe. Testing of poultry samples, which were presumptive positive for Campylobacter following culture on the Malthus V analyzer, with the PCR-ELISA determined Campylobacter to be present in 100% of samples (n = 40) with mixed cultures of C. jejuni/C. coli in 55%. The PCR-ELISA when combined with culture pre-enrichment is able to detect the presence of Campylobacter and definitively identify C. jejuni and C. coli in culture-enriched poultry meat samples.

Admissions to Irish hospitals from nursing homes are recognized as a high-risk category for methicillin-resistant Staphylococcus aureus (MRSA) colonization. This study was conducted between August 1994 and May 1995 to determine the prevalence of MRSA within six Eastern Health Board elderly care nursing homes. A point prevalence survey was conducted in each home on two separate occasions at an interval of five to six months. An MRSA prevalence rate of 8.6% (65 of 754 residents) was recorded for the first survey, and an increased prevalence rate 10.1% (75 of 743 residents) for the second. The prevalence rates within individual homes varied from 1-27%. The body site most commonly colonized was the nares (83%), as anticipated. The main unexpected finding was a low wound colonization rate of 12%, which increased to only 20%, among MRSA positive residents. The dynamic state of MRSA colonization within nursing homes was documented among the 587 residents screened in both surveys. The MRSA positive status of 19 residents remained unchanged, but 32 who were initially positive became negative, while 34 residents acquired the organism. Twenty-six of the 56 (46%) residents identified as MRSA positive in the second survey had acquired the organism within the nursing home over the preceding five to six months. These findings suggest that 'infection control' interventions could have a significant impact on MRSA prevalence within nursing homes.

Risk factors predictive of methicillin-resistant Staphylococcus aureus (MRSA) colonization in 786 of 910 nursing home residents were evaluated. A customized questionnaire was completed by theresidents, who were screened for MRSA. The risk factors significantly associated with MRSA colonization were male sex, age >80 years, residence in the nursing home for

Campylobacter enteritis in humans has been linked to consumption of poultry meat. Surveys show that 30-100% of poultry harbour Campylobacter as normal flora of the digestive tract which indicates a need to identify prevalent organism types in flocks and trace their epidemiology. In this study we describe a Campylobacter genus specific polymerase chain reaction (PCR) assay, amplifying the 16 S-23 S rRNA intergenic spacer region with an internal Campylobacter genus specific DNA probe and species specific probes for Campylobacter jejuni and Campylobacter coli designed for confirmation of the amplified PCR products by Southern blot and colorimetric reverse hybridization assays. The specificity of this assay was established by testing a range of food pathogens. Broiler chicken samples were tested following presumptive positive identification by the Malthus System V analyser (Malthus Instruments, UK). The combined PCR and colorimetric reverse hybridization assay is easy to perform and faster than conventional methods for confirmation and identification of Campylobacter species., (Copyright 2000 Academic Press.)

Cellular interactions control lymphocyte localization within salivary gland tissues and contribute to the immune defense of oral surfaces. We examined lymphocyte adherence to cultured parotid cells using an in vitro assay and found good correlation with previously reported binding to parotid gland frozen sections. Thoracic duct lymphocytes (TDL) bound to parotid cells in greater numbers than thymocytes (74 vs 11 cells/mm2). B cells showed preferential adherence compared to T cells (75% vs 28%). TDL binding was inhibited by sodium azide or cytochalasin B (60% and 80%, respectively). EDTA inhibition (63%) was restored by replacing calcium (9%) but not magnesium (65%). Binding was inhibited by fucoidin or phosphomannan (approximately 70%). Fibronectin peptides had no effect. Culture supernatants were inhibitory for TDL adherence (60%), suggesting that molecules involved in lymphocyte localization may be shed and that parotid cell cultures will be useful for ligand isolation and characterization.

The role of nasal-associated lymphoid tissue (NALT) as a mucosal inductive site for tear IgA antibody responses was investigated in the rat model. Fluorescent microspheres were shown to access and be taken up by NALT after intranasal of ocular-topical administration, although fewer microspheres were found in the latter case. Tear IgA anti-DNP antibody responses to dinitrophenylated Streptococcus pneumoniae were 6 micrograms/ml at day 7, 10 micrograms/ml at day 10, and were still detectable on day 21 (5 micrograms/ml) following ocular or gastrointestinal immunization. Intranasal immunization induced tear IgA responses which were 1.7-fold higher at day 7 (10 micrograms/ml), peaked by day 10 (14 micrograms/ml) and were still 1.6-fold higher (8 micrograms/ml) at day 21 than responses of ocular or gastrointestinal groups. These findings suggest that intranasal immunization may be more effective than ocular or gastrointestinal administration in eliciting tear IgA antibody responses and, taken together with the microsphere data, indicate that NALT can serve as an inductive site for ocular mucosal IgA responses.

Marker expression was studied in rat lymphocyte populations isolated from parotid, submandibular and sublingual salivary glands. Comparative data were also obtained for lacrimal gland and spleen populations. Increased percentages of Thy-1+ cells were found in salivary gland populations when compared to spleen with the highest percentage noted for parotid gland. Thy-1 percentages in parotid gland were comparable to those obtained with lacrimal gland. Salivary gland sIg, CD5 and CD8 cell percentages were lower than those obtained for lacrimal gland and splenic populations. The percentages of CD4-bearing cells in submandibular and sublingual gland were lower than those found in parotid gland, lacrimal gland and spleen, and the CD4:CD8 ratios in parotid gland most closely approximated those in spleen. Increased percentages of Thy-1+ lymphocytes coexpressing sIg and CD5 were obtained for all salivary gland cell populations when compared to spleen; however, percentages of salivary gland cells bearing these 3 markers were lower than noted for lacrimal gland, which contained the highest percentage. With respect to adhesion molecules, lymph node homing receptor (LNHR) and Peyer's patch homing receptor (PPHR) bearing cells were found in all glandular populations with the percentages of LNHR+ exceeding PPHR+ lymphocytes. Homing receptor bearing populations were highest in spleen and were present in equal proportions. LFA-1 was expressed by all salivary gland cell populations in greater percentages than lacrimal gland, but lower than those in spleen. VLA-4 and CD44 expression was higher in parotid gland and spleen than in submandibular and lacrimal gland. These data show that the phenotypes of resident lymphocytes in salivary gland tissues differ from lacrimal gland and spleen, as well as each other, and indicate that Thy-1+ cells in glandular tissues bear both B and T cell markers. The adhesion molecule expression data suggest that these molecules may be utilized differently in various glandular tissues, potentially contributing to the variation in phenotypic profiles of resident glandular lymphocytes.

Salivary immune responses depend on localization of immunocytes in salivary glands. We tested effects of anti-adhesion molecule antibodies and several ligand analogs on in vitro adherence of rat thoracic duct lymphocytes (TDL) to parotid and submandibular gland sections. While TDL adherence to both tissues was markedly decreased by anti-L-selectin mAbs, binding ability after removal of L-selectin by chymotrypsin or PMA suggested that other adhesion systems were involved. Integrin involvement in parotid interactions was indicated by inhibitory effects of anti-HEBF(PP), LFA-1, ICAM-1, and alpha4 integrin antibodies as well as by the PMA-enhanced adherence. Anti-Thy-1 partially inhibited TDL binding to parotid gland, and anti-CD44 partially inhibited submandibular binding. The majority of salivary gland-bound TDL were sIg+ B cells. FACS analysis showed differences in parotid and submandibular endogenous lymphocyte adhesion molecule expression with greater percentages of L-selectin, HEBF(PP), alpha4 integrin, LFA-1, ICAM-1, CD44, and Thy-1-positive cells present in parotid gland. While precise roles of known or novel adhesion molecules in salivary gland lymphocyte retention are not clear, these data suggest that selectins (parotid, submandibular), integrins (parotid), Thy-1 (parotid), and CD-44 (submandibular), as well as other unidentified molecules, are involved.

This study utilized DNA fingerprints and crosses of two genetically distinct lines of layer-type chickens to identify genetic markers linked to quantitative trait loci (QTL). In phase I, backcross (BC1) hens were separately ranked for each of eight traits and then blood pools were produced in groups along each phenotypic distribution. The DNA was isolated from the blood pools and used in a gradient analysis to screen for DNA fingerprint bands that exhibited intensity gradients associated with the phenotypic traits. To identify linkage of bands with QTL and to estimate band effects, F2 progeny were produced in phase II from the phase I BC1 population. A single-trait animal model was used for analysis of associations of all individual DNA fingerprint bands of sires and their progeny phenotypic performance. Twenty fingerprint bands, only two of which had shown trait-associated gradients in phase I, were identified by the animal model analysis of the progeny test as QTL linked (P < or = 0.05) to specific traits of growth, reproduction and egg quality. These 20 bands warrant further study as potentially valuable molecular markers for QTL.

Purpose: In lacrimal glands, cell-cell interactions control the localization of lymphocyte populations that play a role in immune defense at the ocular surface. This study describes lymphocyte adhesive interactions with cultured lacrimal gland acinar epithelial cells., Methods: Primary cultures of lacrimal gland epithelial cells were used as targets for in vitro lymphocyte binding assays. The relative adherence of lymphocyte populations was determined. Various physiologically active agents and putative ligand analogs were tested for their effect in the binding assay., Results: Thoracic duct lymphocytes (TDL) bound to cultured lacrimal acinar epithelial cells in greater numbers than did thymocytes (54 cells/mm2 versus 8 cells/mm2). B cells showed preferential adherence compared with T cells (75% sIg+, 14% W3/13+). Thoracic duct lymphocyte binding required intact metabolic and membrane-cytoskeletal function and was inhibited by treating the lymphocytes with sodium azide, formaldehyde, or cytochalasin B (23%, 12%, and 10% of control binding, respectively). Further, adherence was dependent on divalent cations. Ethylenediaminetetraacetic acid-mediated inhibition (42% of untreated) was restored by replacing calcium (89%) but not magnesium (41%). Lymphocyte adherence was inhibited in the presence of fucoidin or phosphomannan polysaccharides (36% and 48% of control binding, respectively). Fibronectin peptides, which are involved in certain types of integrin-mediated adherence, had no effect in this system. Lacrimal culture supernatants contained a factor that was inhibitory for TDL adherence (more than 50% inhibition when concentrated 5 or 10 times)., Conclusions: Thoracic duct lymphocyte adherence to cultured lacrimal gland acinar epithelial cells shows good correlation with previously reported adherence to lacrimal gland frozen sections. Further, lacrimal cell culture supernatants contain soluble factors that inhibit TDL adherence to epithelial cells. These findings suggest that the lacrimal molecules involved in lymphocyte localization are shed and that lacrimal epithelial cell cultures will be useful for ligand isolation and characterization.

The synthesis of the indolequinones 8 and 9 starting from methyl 4-(benzyloxy)-5-methoxy-indole-2-carboxylate (10) is described. The methoxy group in the indolequinones 1, 2, 4, 5, and 7-9 can be displaced by various nitrogen nucleophiles (ammonia, 2-methoxyethylamine, aziridine, 2-methylaziridine, pyrrolidine) in 22-88% yield. The resulting amino-substituted quinones, together with their methoxy precursors, were studied by cyclic voltammetry to determine their reduction potentials, which, in DMF solution, lie in the range -1.355 to -1.597 V (vs ferrocene). The cytotoxicity of the compounds towards aerobic and hypoxic mammalian cells was also determined; in general, under aerobic conditions, the cyclopropamitosenes are more toxic than the corresponding pyrrolo[1,2-a]indolequinones, which are in turn more toxic than the simple 1,2-dimethylindolequinones, with many of the compounds in each series showing greater toxicity toward hypoxic cells.

The mechanism of action of cyclopropamitosenes, novel bioreductive anticancer agents, has been investigated using a unique combination of chemical and biochemical techniques. The compounds 4 function as reductively activated alkylating agents under chemical reducing conditions, and the biochemical experiments establish that the methoxy- and aziridinyl-derivatives 4a and 4b behave differently upon bioreduction.

The selective interaction of trafficking lymphocytes with glandular epithelial cells is thought to link the lacrimal gland (LG) to the mucosal immune network. An in vitro binding assay was used to determine the phenotype of adherent cell populations and to study the involvement of lymphocyte adhesion molecules in the adherence process. Enriched B cell populations showed greater binding to LG epithelium than did enriched T cell populations. Direct phenotyping of adherent lymphocytes demonstrated that B lymphocytes (particularly IgA+ and IgG+ cells) were the predominant participants in LG binding. In vitro binding to LG acinar epithelium was inhibited by mAb with specificity for rat lymph node and Peyer's patch homing receptors and, to a lesser degree, by anti-VLA-4 and LFA-1 but not by anti-CD44 or Thy-1. In addition, the presence of rat lymph node and Peyer's patch homing receptors on endogenous LG lymphocytes was demonstrated by flow cytometry. These data show that B cells are the predominant population adhering to LG epithelium and suggest that lymphocyte homing receptors mediate the adherence process. These findings indicate that selective interactions between lymphocytes and the glandular epithelium contribute to the presence of IgA-producing cells in the LG.

Mature circulating lymphocyte populations specifically bind to lacrimal gland acinar epithelium in vitro and this adherence is thought to contribute to the accumulation of lymphoid subsets within lacrimal tissue in vivo. The regulatory role of interleukin-4 (IL-4) and transforming growth factor-beta (TGF-beta) in this adherence process was examined using an in vitro binding assay. Pretreatment of thoracic duct lymphocytes (TDLs) with increasing concentrations of IL-4 or TGF-beta for 1 hr resulted in a dose-dependent inhibition of lymphocyte binding to lacrimal gland acinar epithelium. In contrast, the binding of TDLs to high endothelial venules of cervical lymph node was not inhibited by either cytokine. Further, IL-4 and TGF-beta pretreatment did not alter the expression of lymph node or Peyer's patch homing receptors as well as the LFA-1, VLA-4, or CD44 adhesion molecules on TDLs. These results suggest that the interaction of lymphocytes with lacrimal gland acinar epithelium may be regulated by a receptor-mediated mechanism that differs from those governing HEV recognition.

Glandular mucosal tissues contain lymphocyte populations that contribute to expression of IgA antibodies in external secretions. Interaction of circulating lymphocytes with glandular structures may regulate lymphocyte accumulation. An in vitro assay was used to investigate adhesive interactions between lymphocytes and salivary gland tissues. Thoracic duct lymphocytes (TDL) bound to the serous acinar epithelia of parotid salivary glands and to the mucous tubulo-acinar epithelium of submandibular salivary glands. Lymph node cells and splenocytes adhered to these tissues in lesser numbers and thymocytes bound in negligible numbers. TDL adherence was an active process, being time- and cell dose-dependent and requiring intact membrane as well as cytoskeletal and metabolic function. Calcium was required in each case and binding was mediated by a trypsin-sensitive lymphocyte surface determinant. These findings suggest that the lymphocyte composition of salivary gland tissues is regulated by active lymphocyte interaction with the glandular epithelium.

Objective: To determine an effective screening procedure for microalbuminuria., Research Design and Methods: The prevalence of microalbuminuria in NIDDM patients whose urine was negative on routine Albustix testing was studied. Microalbuminuria was measured in overnight urine samples from 128 NIDDM patients on at least two of three occasions over a 6-mo period. Patients were tested with Micro-Bumintest or Micral-Test., Results: Ten of 128 patients had albumin concentrations > or = 20 mg/L on two or more occasions, 14 patients had A-C ratios > or = 3 mg/M on two or more occasions, and 9 patients had both., Conclusions: Neither Micro-Bumintest nor Micral-Test is a useful or feasible screening procedure for microalbuminuria.

Eight healthy volunteers received a 1,000-mg single oral dose of 2085P which consisted of 800 mg of pivampicillin and 200 mg of brobactam. Concentrations of ampicillin and brobactam in plasma, inflammatory fluid, and urine were measured over the subsequent 24 h. Pivampicillin and brobactam were moderately rapidly absorbed. The mean (standard deviation) maximum concentration in plasma (Cmax) of ampicillin was 8.2 (1.9) micrograms/ml, and that of brobactam was 2.1 (2.0) micrograms/ml at mean times of 1.9 (0.5) and 2.3 (0.8) h, respectively. The elimination half-lives in plasma were 1.8 (0.5) and 1.6 (2.0) h, respectively. Both agents penetrated the experimentally induced inflammatory fluid, reaching a mean maximum at 3 h. The Cmax of ampicillin was 6.8 (2.3) micrograms/ml, and that of brobactam was 1.0 (0.4) micrograms/ml. The penetration (derived by comparing the area under the concentration-time curve from 0 h to infinity for inflammatory fluid with that for plasma) was 97.3% (26.0%) for ampicillin and 81% (22.3%) for brobactam. The 24-h urinary recovery was 54.2% (16.6%) of the administered dose for ampicillin and 40.2% (11.4%) for brobactam. These data suggest that this combination of beta-lactam and inhibitor should be efficacious in treating infections caused by ampicillin-resistant pathogens.

Correlated responses for growth, feed intake, and feed utilization were measured in female chickens from lines after 32 generations of divergent selection for 56-day body weight and in sublines in which selection had been relaxed for five generations. The diet used in the present experiment was that under which selection had been practiced (20% crude protein and 2,685 kcal of ME/kg). Feed intake between each selected line and its relaxed subline was equalized by paired-feeding. Ad libitum-fed controls were also maintained. At 21 days of age, differences between the selected lines for ad libitum-fed chickens were 404% for body weight, 279% for feed intake, and 138% for feed conversion ratio (FCR). Respective percentages for the high and low relaxed lines under ad libitum feeding were 267, 223, and 121%. When pair-fed, the growth of the line selected for high weight was unimpeded and FCR improved. When chicks of the low-weight relaxed line were pair-fed, FCR also improved, but growth was reduced and appetite development inhibited. Hyperphagic behavior was observed in the line selected for high weight. In the low-weight selected line, the chicks exhibited hypophagia. Although residual feed consumption was unchanged by selection for 56-day body weight, variation was present for this trait, with lower values under restricted than ad libitum feeding.

Growth of organs relative to body weight and cellular protein, RNA, DNA, and cell unit size of breast muscle, liver, and small intestinal tissue were measured in females from four lines of chickens. Two lines had undergone 32 generations of divergent selection for 56-day body weight, and the other two lines were derived by sampling the first two lines at Generation 28 and relaxing selection for the next five generations. The diet used in the present experiment was the same diet under which selection was practiced (20% crude protein and 2,685 kcal of ME/kg). Comparisons at common chronological ages and a common body weight revealed that supply organ weights, especially that of the small intestine, were associated with subsequent growth of demand organs. Although the upper gastrointestinal tract was also important in this respect, it was more susceptible to influences such as feed intake. Selection for juvenile body weight resulted in correlated changes in cell size of breast muscle but not liver and small intestine. Muscle increased posthatch as cells underwent hypertrophy but liver and small intestine grew chiefly by hyperplasia.

Levels of amylase, trypsin, chymotrypsin, and lipase in the pancreas and small intestinal chyme were measured in females from four lines of chickens. Two of the lines had undergone 32 generations of divergent selection for 56-day body weight, and in the other two lines selection for high or low weight had been relaxed for 5 generations. The diet used in the present experiment was that under which selection had been practiced (20% crude protein and 2,685 kcal of ME/kg). Comparisons between divergently selected lines at common ages revealed higher enzyme levels for high- than low-weight lines. When comparisons were made at a common body weight (80 +/- 5 g) there were no differences between lines. These results suggested that correlated responses in feed intake were mediating the regulation of digestive enzyme levels in the pancreas and in intestinal chyme of growth-selected lines of chickens. Chicks from high-weight lines had elevated enzyme levels after a mild feed restriction compared with those provided ad libitum access to feed. It was hypothesized that hyperphagia associated with the high-weight lines in combination with a mild feed restriction and the associated meal feeding stimulated synthesis and secretion of digestive enzymes.

1. Growth, reproductive characteristics and immunocompetence were evaluated in a line of broiler breeder females segregating at the sex-linked feathering locus when maintained on three feeding regimens with two forms of food in a factorial design. 2. Long-term obesity but not short-term weight gain had deleterious consequences for reproductive characteristics, response to sheep red blood cell antigen, resistance to Escherichia coli and livability. 3. Reproductive performance of early feathering females was superior to that of late feathering ones. Differences were attributed to an association between the allele for late feathering and an endogenous viral locus ev21, which encodes for avian leucosis virus. 4. Reproductive performance of breeders fed crumbles was superior to that of breeders fed a combination of crumbles and fines.

The pharmacokinetics of rufloxacin after a single 400 mg oral dose were studied in eight volunteers, measuring plasma, inflammatory fluid and urine concentrations. Mean peak plasma concentrations of 4.4 mg/L were achieved at a mean time of 1.9 h after administration. The mean plasma elimination half-life was 28.2 h. Mean peak levels in inflammatory fluid reached 3.2 mg/L after 3.5 h, and 30.7% of the dose was eliminated in urine by 96 h. The apparent mean volume of distribution of rufloxacin, at steady state, was 109.5 L. The mean percentage penetration of rufloxacin into the inflammatory exudate, as measured by ratios of AUC0-50 h was 90%.

Fertility, hatchability, and their relationships to age of dam, egg components, embryo growth, and embryo lipid transfer were studied in a broiler breeder line segregating at the sex-linked feathering locus. Early-season increases in hatchability of eggs were due to a reduction in embryo deaths between Day 1 and 7 of incubation. No late seasonal declines in either fertility or hatchability were observed. Although less proficient in young dams, embryo lipid transfer was not directly associated with the lower hatchability of their eggs. Egg weight, weights of 18-day embryos, and embryo:egg ratios increased with parental age. Also with age, there were increases in shell, albumen, and yolk weights. Heavier albumen weight was due to increased moisture content, and those for shell and yolk were due to dry matter accumulation. Changes in yolk:albumen ratios reflected large increases in relative yolk weight, on a wet and dry weight basis, that were associated with age of dam. Eggs from late-feathering dams were heavier than those from early-feathering ones. Heavier embryos by 18 days of incubation were attributed to the transfer of albumen from the egg to the embryo.

Several fitness traits were measured in males from two meat lines fed diets differing in nutrient density ad libitum daily or on alternate days. Criteria of evaluation were antibody response to SRBC, blood heterophil:lymphocyte ratios, incidence of leg deformities, and resistance to Escherichia coli inoculation. Males from the heavier line had lower antibody titers to SRBC inoculation than those of the lighter line. Diets, feeding regimens, and interactions among them did not influence response to SRBC. Lines, diets, feeding regimens, and interactions among them were not significant for heterophil:lymphocyte ratios. Chicks fed daily had a higher incidence of leg deformities than those fed on alternate days. There were no differences between lines or diets, nor were interactions significant. Interactions were present between main variables for response to E. coli inoculation whether the measure was initial weight loss, recovery, or lesion scores, demonstrating the complexity of genotype-environmental relationships in resistance to this infectious agent.

Isolates of Campylobacter jejuni, C coli, C fetus and C laridis were tested for agglutination reactions with a panel of five lectins: Arachis hypogaea, Bauhinia purpurea, Solanum tuberosum, Triticum vulgaris and Wisteria floribunda. Twenty three patterns of agglutination (lectin types) were recorded among 376 isolates. Patterns were consistent and reproducible. Only 4.5% of isolates were untypable because of autoagglutination. Some lectin types were found exclusively or predominantly in a species, but others were shared between species. Forty two per cent of C jejuni and 35% of C coli isolates belonged to lectin type 4. There was no apparent correlation between lectin type and serotype; different lectin types were found among strains of single Penner and Lior serotypes. Lectin typing is a simple and economical procedure suitable for use in non-specialist laboratories, either as an adjunct to serogrouping or, after further development, as a sole typing scheme.

The lacrimal gland is a functional part of the mucosal immune system and is populated by lymphoid cells that begin to appear early in neonatal development. To define the events controlling the accumulation of these cells, an in vitro adherence assay was used to investigate the interactions of lymphocyte populations with neonatal and adult lacrimal tissue. It was found that (1) lymphocytes adherence to neonatal lacrimal tissue is significantly enhanced over that seen in adults; (2) the increased binding is caused, in part, by adherence to nonacinar structures in neonatal tissue; (3) binding to both neonatal and adult lacrimal gland tissue is an active process that is observed only with viable lymphocytes; (4) lymphocyte adherence to neonatal and adult lacrimal gland tissues is differentially affected by metabolic and cytoskeletal inhibitors; and (5) attachment appears to require the presence of Ca++, a lymphocyte surface protein, and may involve target tissue carbohydrate recognition. These findings suggest that the initial accumulation of lymphocytes in the neonatal lacrimal gland results from a generalized enhanced binding capacity of the developing tissue and that the preferential binding of certain populations (thoracic duct and mesenteric lymph node lymphocytes) to acinar cells maintains the pool in the adult lacrimal gland.

Breeding data from Eire and Great Britain confirm the hypothesis of Sponenberg (1985) that the harlequin colour of the Great Dane breed of dog is due the combined action of a dominant gene H with the merle gene M in the genotype H+M+. The typical bluish coloration induced by M is modified to white by the action of H. The H gene is a prenatal lethal when homozygous HH and this study offers clear indication that the heterozygous H+ interacts with M to reduce the viability of white merle homozygotes H+MM.