Comparative effects of in ovo versus subcutaneous administration of the Marek's disease vaccine and pre-placement holding time on the intestinal villus to crypt ratios of Ross 708 broilers during early post-hatch development1,2,3.

Villus to crypt ratio (VCR) is used to quantify the microanatomical response of the intestine to various treatments. In early age chickens, comparative effects of the in ovo (i.o.) and s.c. methods of administration (moa) of the Marek's disease (MD) vaccine on 2 types of measurement of small intestinal VCR at 0 and 4 h post-hatch (poh) were investigated. The effects of moa and 4 and 18 h pre-placement holding times (pht) on the VCR measurements at 168 h (7 d) poh were also investigated. In the jejunum of the small intestine, a standard method for VCR determination, based on 10 villus and crypt length measurements, was utilized for the calculation of villus to crypt length ratio (VCLR). In that same region, a single histomorphometric determination of the crypt and total mucosa areas using image analysis software was also used. Subtraction of the crypt area from the total mucosa area provided the villus area, allowing for calculation of the villus to crypt area ratio (VCAR). Across 0, 4, and 18 h of poh bird age, the VCLR of birds that received an s.c. vaccination was higher in comparison to that of those that received an i.o. vaccination. The highest and lowest VCAR values were observed in the s.c. treatment at 0 h poh and in the i.o. treatment at 4 h poh, respectively. Furthermore, at 168 h poh, VCLR values in the 18 h pht and s.c. vaccination group were higher than those in the 4 h pht and s.c. vaccination or 18 h and i.o. vaccination groups. In conclusion, the effects of pht and MD vaccine moa on VCR were dependent on the use of either the VCLR or VCAR method of measurement. However, regardless of method, s.c. injection overall led to a higher VCR through 4 h poh in Ross 708 broilers, and the effects of moa on VCLR at 168 h were influenced by pht.

Comparison of two methods for determination of intestinal villus to crypt ratios and documentation of early age-associated ratio changes in broiler chickens,.

The determination of intestinal villus to crypt ratios (VCR) is a common method utilized to evaluate effects of various diet regimens on gut microanatomy and for the histologic quantification of intestinal responses to disease processes. Two methods for the determination of small intestinal VCR were compared in early age chickens. A standard method for VCR determination based on 10 villus and crypt length measurements in the jejunal region of the small intestine was employed for the calculation of villus to crypt length ratio (VCLR). That method was compared to a new approach based on a single histomorphometric determination of the crypt and total mucosal areas using image analysis software. Subtraction of the crypt area from the total area provided the villus area and allowed for the subsequent calculation of villus to crypt area ratio (VCAR). At 4 and 18 h posthatch, VCLR was higher than that of VCAR, but there was no significant difference between VCLR and VCAR at 0 h (hatch) and at 168 h (d 7) posthatch. Nevertheless, the pattern of age-associated changes for VCLR and VCAR were comparable throughout the early posthatch period. Furthermore, the new method used in determining VCAR is subject to less human error, allows for an appreciable reduction in the number of measurements required, and facilitates a larger intestinal segment evaluation. Standard linear measurements require the selection of variable numbers of villi and crypts, whereas the area method only requires selection of a single region that incorporates numerous villi and crypts of variable sizes in providing a less subjective approach. This is particularly advantageous in studies on intestinal disease conditions resulting in marked multifocal variation in villus stature. This study further documented age-associated changes occurring in the VCR of the small intestine during the early posthatch period. Across the 2 methods used for VCR determination, a major and highly significant reduction in the VCR was observed to occur between 18 h and 168 h posthatch.

Stem cell intervention ameliorates epigallocatechin-3-gallate/lipopolysaccharide-induced hepatotoxicity in mice.

Stem cells are identified as a novel cell therapy for regenerative medicine because of their ability to differentiate into many functional cell types. We have shown earlier a new model of hepatotoxicity in mice by administering (1500 mg/kg) epigallocatechin-3-gallate (EGCG) intragastric (IG) for 5 days after a single intraperitoneal dose (6 mg/kg) of lipopolysaccharide (LPS). In this study, we aimed to study the effect of intrahepatic (IH) injection of mouse embryonic stem cells (MESCs) on the hepatotoxicity induced by EGCG/LPS in mice. Mice were administered EGCG/LPS and rested for 3 days. MESCs were obtained from American Type Culture Collection and cultured in vitro for 4 days. Stem cells were injected IH. Seven days later, a single dose of LPS (6 mg/kg) followed by daily doses of IG administration of EGCG were re-administered for 5 days. At the end of the experiment, blood samples were collected for analysis of biochemical parameters associated with liver. Results showed that the group of mice that were administered MESCs prior to EGCG/LPS showed lower levels of alanine amino transferase, alkaline phosphatase, and bilirubin, higher albumin/globulin ratio, and less remarkable histopathological lesions. Also, that group of mice showed less expression of oxidative stress biomarkers (oxidized low-density lipoprotein Ox.LDL and chemokine CXCL16), less expression of nuclear protein receptors (retinoic acid receptor and retinoid X receptor), and less expression of inflammatory biomarkers (tumor necrosis factor α and transforming growth factor ß1) compared with other groups of mice that were not given MESCs. In conclusion, MESCs can ameliorate EGCG/LPS-induced hepatotoxicity in mice.

The os acromiale: another cause of impingement.

Impingement of the shoulder is a relatively common clinical entity. The os acromiale anomaly is an uncommon one (1-8%) but can be an important cause of the impingement syndrome. The most common place of nonfusion is between the meso- and meta-acromion. The key to diagnosis is a history and physical examination compatible with the impingement syndrome and appropriate radiologic studies (i.e., an axillary view or profile view or computed tomographic scan if necessary). After diagnosis, the initial treatment is conservative with rest, ice, nonsteroidal anti-inflammatory drugs (NSAIDs), injections of corticosteroids in the subacromial space, and most importantly, an appropriate rehabilitation program. If unsuccessful, treatment should be planned based on the size of the unfused fragments. Small fragments (< 4 cm) may be removed by either arthroscopic or open means. Larger fragments may require an attempt at bone grafting and fixation since their removal may result in loss of strength of the deltoid.

Thymus-leukemia antigen interacts with T cells and self-peptides.

The functional role of the class Ib thymus-leukemia (TL) Ag expressed within the thymic cortex and intestinal mucosa of the mouse remains unknown. In an approach to elucidate the potential functionality of TL, we developed transgenic mice that ectopically express the H-2T18d gene product on essentially all nucleated cells through the control of a heterologous H-2Kb gene promoter. Transgenic mice demonstrated an increase in the number of CD4+ lymphocytes within the thymus and lymph nodes; these cells displayed an altered T cell receptor repertoire possibly suggesting a role for the ectopically expressed TL protein. The TL protein additionally displayed the characteristics of a bona fide transplantation Ag, because skin grafts from transgenic animals onto MHC- and minor histocompatibility Ag-matched nontransgenic recipient mice resulted in a rapid and vigorous immunologic rejection of the allograft. In MLR studies, transgenic stimulator cells induced the proliferation of responders to a level intermediate between genetically identical and H-2-disparate responder-stimulator combinations. The TL protein was also capable of stimulating cytotoxic T lymphocytes, thereby resulting in specific lysis of TL+ target cells. Further data demonstrated that the TL protein assembles with peptides that are modified at the amino terminus, and that TL retains these molecules at the cell surface. Together, these data suggest that H-2T18d is capable of interacting with T cells via a bound peptide. These data further support the possibility that TL may subserve a specialized function within the immunologic system.

Diagnosing Posterolateral Rotatory Knee Instability.

In brief A recent case of posterolateral rotatory knee instability in a recreational athlete provides an opportunity to review diagnosis and treatment of this often unrecognized condition. Two simple clinical tests, the external rotational recurvatum test and the posterolateral drawer test, can identify this injury to the arcuate ligament complex. Treatment consists of bracing and physical therapy and, in some cases, surgery.

Waterskiing's Impact on Knees.

In brief Knee dislocation is a rare but brief potentially catastrophic water-skiing injury. Our patient sustained a fracture-dislocation of the knee and, because of vascular damage, required amputation of his lower leg. A subsequent survey of approximately 150 orthopedic surgeons revealed that, among their patients, the majority of serious knee injuries related to waterskiing resulted from noncontact falls into the water. Dislocation was the most serious consequence recorded, while damage to the tibial collateral ligament occurred most frequently.

Hypertrophy and hyperplasia of the rat pancreas produced by short-term dietary administration of soya-derived protein and soybean trypsin inhibitor.

Feeding soy protein concentrate to weanling rats over a one-week period produced a dose-related increase in pancreatic weight due to an increase in acinar cell size. Hyperplastic changes occur simultaneously, as evidenced by an increase in mitotic activity after two days on the test diet. Similar changes were also obtained by feeding soybean Kunitz trypsin inhibitor over the same time period. The results suggest that this approach may be useful as a model to investigate the effect of plant-derived material on the pancreas, in particular proliferative lesions.

Human CD2 3'-flanking sequences confer high-level, T cell-specific, position-independent gene expression in transgenic mice.

We have localized a set of T cell-specific DNAase I hypersensitive sites in the 3'-flanking region of the human CD2 gene. A 5.5 kb BamHI-XbaI fragment containing these DNAase I hypersensitive sites conferred efficient, copy number-dependent, T cell-specific expression of a linked human CD2 minigene, independent of the position of integration in the transgenic mouse genome. When linked to the mouse Thy-1.1 gene or the human beta-globin gene, this fragment conferred the same T cell-specific expression, independent of its orientation. These results suggest that this flanking region is both necessary and sufficient for full tissue-specific activation of homologous and heterologous genes in transgenic mice.

Components of change in migration and destination-propensity rates for metropolitan and nonmetropolitan areas: 1935-1980.

This article focuses on components of change in out-migration and destination-propensity rates of metropolitan and nonmetropolitan areas. The results indicate that changes in subgroup-specific rates were the driving force behind the changing patterns between and within these two areas. Composition effects played a secondary role, mainly counteracting the negative impact of changing rates. Although the rate of change in out-migration from metropolitan areas has been reduced and out-migration from nonmetropolitan areas declined during the most recent period, the propensity to select metropolitan areas increased over the period studied. Finally, rate-specific changes vary by age and education, indicating a change in migration's impact on population composition at origin and destination.

Metropolitan and nonmetropolitan migration streams: 1935-1980.

Results based on an analysis of migration streams involving the metropolitan and nonmetropolitan sectors and covering a longer time interval than previously possible indicate that efforts to describe changes in the volume of movements connecting these sectors could benefit from greater attention to other related streams as well as existing patterns of population concentration. The metropolitanization process continues but is now being affected substantially by regional redistribution trends. Regional differentials in the size of metropolitan and nonmetropolitan migration streams are declining but are still substantial, so an equilibrium balance between the metropolitan and nonmetropolitan sectors will probably not occur in the immediate future.

Stimulation of normal rat bone marrow fibroblast proliferation by sera from leukemic Fischer rats.

Fibroblast hyperplasia and accumulation of fibrous material in the bone marrow of patients with idiopathic (primary) or secondary myelofibrosis (MF) is believed to result from a reaction by marrow fibroblasts to an altered marrow microenvironment, the alteration being potentiated by abnormal hemic cells. We investigated the hypothesis that humoral factors might contribute to fibroblast overgrowth in MF by using an animal model, aged Fischer rats, where MF frequently occurs with leukemia. Sera from leukemic rats and leukemic cell conditioned media (CM) were assayed for enhancement of normal rat marrow fibroblast proliferation in a culture system where fibroblasts form discrete, adherent colonies. Our results demonstrated that: leukemic sera induced a 170% increase in total fibroblast colony numbers and a 325% increase in colonies containing more than 80 cells, stimulation of fibroblast growth was leukemia related since sera from rats with transplanted leukemia enhanced marrow fibroblast proliferation, leukemic cell CM did not contain a growth factor for marrow fibroblasts, sera from leukemic rats and 2-mercaptoethanol were additive in enhancing marrow fibroblast proliferation and probably act by different mechanisms, and leukemic rat sera was less effective as a colony-stimulating factor than normal rat sera, a condition mimicked when leukemic and normal spleen CM were compared. This is the first time that a serum component has been implicated in the pathogenesis of MF; our work may contribute to understanding the mechanism involved when MF occurs as a complication of leukemia.

Chronic and acute trypanosomiasis in mice: a study by in vitro cloning of lymphohaematopoietic progenitors.

A semi-solid culture system was used to study the effects of trypanosome infection in two species of mice on the propagation of progenitor cells from the bone marrow and spleen. The deer mouse (Peromyscus maniculatus) survived infection with Trypanosoma (T.) equiperdum for more than 15 days. During the first 10 days there was inhibition of development of granulocyte-monocyte colonies from progenitor cells in the bone marrow. B-lymphocyte progenitors in the spleen showed increased activity, producing colonies 140-300% above normal control groups during the same period. - Conversely, all Balb/c mice infected with the trypanosomes died within 10 days with fulminating parasitemia and massive spleen enlargement. There was a general activation of progenitor cells; B-lymphocytes from the spleen and bone marrow and granulocyte-monocyte colonies from bone marrow, although this was not sustained more than 4 days after infection. - In chronically infected deer mice the pattern of response of the bone marrow and spleen progenitor cells was significantly different over successive weekly intervals. Periodicity of response in these organs was displayed by recurring waves of activation and depression of the progenitor cells. - Thus, there were significant differences in response patterns of deer mice and Balb/c mice to T. equiperdum infection which could be established by the behavior of host lymphohaematopoietic progenitor cells in culture. We therefore suggest that such in vitro cultures may be useful in assessment of the immune response to trypanosomiasis by the host and also for the study of the pathology of both chronic and acute trypanosomiasis.

Effect of continuous, whole-body gamma irradiation upon canine lymphohematopoietic (CFU-GM, CFU-L) progenitors and a possible hematopoietic regulatory population.

Clonogenic assays for granulocytes-macrophages (CFU-GM) in bone marrow and for T lymphocytes (CFU-L) in peripheral blood were performed on dogs continuously exposed to 60Co irradiation (0.02, 0.04, or 0.11 Gy/day). When decreased numbers of CFU-GM were observed they correlated well with the clinical status of the dogs but were not generally associated with increasing cumulative doses of absorbed irradiation. In clinically normal, irradiated animals, decreased CFU-GM values and myeloid-erythroid ratios were observed, suggesting that chronic irradiation may affect the granulocytic series well before decreased peripheral blood values are seen. In hypocellular dogs the number of CFU-GM were significantly decreased compared to values obtained from control or clinically normal irradiated dogs, while virtually no CFU-GM were observed in the leukemic dogs. Only the CFU-GM values of the hypocellular group showed an association, e.g., a suggestion of an abortive regenerative effort, with increasing absorbed dose. Proliferative capacity of T lymphocytes (CFU-L) was not affected by either increasing absorbed irradiation or the presence of leukemia. D0 values were determined on marrow fibroblastic cells to ascertain whether a radioresistant subpopulation of stromal elements would result from continuous in vivo irradiation. No correlation was found between absorbed dose and increased D0 values. However, seven of eight dogs which developed acute nonlymphocytic leukemia displayed marrow fibroblastic cells with elevated D0 values. These radioresistant marrow fibroblastic cells were assayed for their ability to support normal granulopoiesis and found to be not significantly different from control fibroblasts.

Increased in vitro radioresistance of bone marrow fibroblastic progenitors (CFU-F) from patients with acute non-lymphocytic leukemia.

The proliferative potential following in vitro irradiation of bone marrow fibroblastic progenitors (CFU-F) derived from four patients with acute nonlymphocytic leukemia (ANLL) and seven nonleukemic subjects was compared. The CFU-F from the ANLL patients were significantly more radioresistant than the CFU-F from the nonleukemic subjects. The increased radioresistance in ANLL patients was evident in both the mean slope of the survival curve (control = -0.385, ANLL = -0.256) and in the Do values (control = 2.68 Gy, ANLL = 4.61 Gy). Thus CFU-F derived from ANLL patients differ from those derived from nonleukemics in both radioresistance and in granulopoietic effects as suggested from previous studies.

Urban ecology: urbanization and systems of cities.

"This paper reviews the literature on the nature and extent of interrelations among cities in advanced industrial societies. It summarizes contemporary population distribution and redistribution trends in these societies and their causes. Finally, it attempts to identify some of the most important issues for the development of a comparative theory of urbanization."

Pathology of the mononuclear cell leukemia of Fischer rats. II. Hematology.

Complete hemograms were evaluated for 57 rats with mononuclear cell leukemia and compared to hemograms obtained from 52 age- and sex-matched nonleukemic rats. All leukemic rats had marked hemolytic anemia and associated spherocytosis, reticulocytosis, anisocytosis, and polychromasia. The anemia varied with the stage of illness and was more severe in rts with advanced leukemia. Death appeared to be related to anemia. There was a marked neutrophilia with left shift, mild lymphopenia, and moderate to severe thrombocytopenia. Atypical mononuclear cells were detected in circulation in all but three rats. Total white blood cell counts ranged from 5.0-370 x 10(3) cells/ml. There was an increase in erythrocyte osmotic fragility with separation into two distinct populations of erythrocytes. Eight of nine rats were Coombs' positive indicating an immune-mediated pathogenesis for the anemia. Hemostasis tests revealed a markedly prolonged prothrombin time, hypofibrinogenemia, slightly increased to normal partial thromboplastin time, and undetected fibrin degradation products. These findings suggest significant liver disease associated with the leukemia.