Morphology of Gut-Associated and Bronchus-Associated Lymphoid Tissues of Calves in Relation to Age

The macroscopic, light and scanning and transmission electron microscopic structure of gut-associated lymphoid tissue (GALT) of small and large intestines and bronchus-associated lymphoid tissue (BALT) were studied in the 3, 6 and 8 monthold calves. Results showed that two different types of Peyer’s patches (discrete and continuous) were present in the small intestine. Discrete Peyer’s patches (dPP) were located in the duodenum and jejunum and continuous Peyer’s patches (cPP) were located in the ileum. The number, size, shape and distribution of Peyer’s patches (PP) in small intestine varied between individuals of the same group and between age groups. There were significantly more (p<0.05) dPP found in the jejunum part compared to that of duodenum. The number of dPP increased significantly (p< 0.05) from 3 to 6 month but this number of dPP significantly (p< 0.05) declined after 6 month of age. However, the size and distance between dPP were not significantly (p> 0.05) differences between 6 and 8 month-old calves. The cPP of the ileum was found to be raised above the level of mucosa in the 6 month-old calves. Its size decreased significantly (p< 0.05) after 6 month.Under light microscope revealed the presence of elongated follicles with very small interfollicular areas (IFAs) in ileal PP (cPP) and small pear shape follicles with large IFAs were found in the duodenal and jejunal PP (dPP). Based on the morphometric analysis, the number of jejunal lymphoid follicles and size of ileal lymphoid follicles of the 6 month-old calves were significantly higher (p<0.05) than those of 3 and 8 month-old calves. The width of IFAs of PP of small intestine increased with age. The number and size of dome of PP in small intestine of 6 month-old calves were significantly higher (p<0.05) than those of 3 and 8 month-old calves. Two types of follicle-associated epithelium (FAE), FAE of villi and FAE of crypts were found in this study. The intrafollicular invaginations of dome epithelium of duodenal PP (dPP) were found in all ages. Three morphological changes in the involuted Peyer`s patches were found in the ileum of the 8 month-old calves. The changes were: 1) the dome epithelium invaded into the follicle and formed intrafollicular surface epithelium, 2) depletion of follicle with replacement by the connective tissue and formation of acellular cavity in the follicles and 3) the domes became atrophied and all villi were thickened and shrunken. M cells in FAE of dPP were randomly distributed and the morphological structures of M cells in FAE of cPP were found to be same characteristic. SEM findings revealed that the apical surface of M cells of dPP had irregular, sparse microvilli and some M cells were completely encroached up by adjacent absorptive cells. In cPP, the luminal surface of some M cells had few or lack microvilli and various sizes of vacuoles containing particles or lymphocytes on their surface.Under the transmission electron microscope, mature and immature M cells were observed to be present in FAE of dPP and cPP of all age of studied. Mature M cells of dPP were tall columnar shape cells with less electron dense cytoplasm containing mitochondria with closely packed cristae and lymphocytes include into the cytoplasmic pocket. An irregular shaped nucleus was located toward the base of the cell and vesicles were presence at the base of microvilli. Multivesicular electrondense bodies were found in the cytoplasm of mature M cell of cPP. Immature M cells containing many mitochondria in the cytoplasm were found in lower dome epithelium. There are cytoplasmic protrusions on the luminal surface of M cells with interdigitating cell membrane at the periphery. In cPP, luminal surface of immature M cells had small microvilli and vacuole, mitochondria; rounded nucleus located at the apical part of the cell. The number and width of Peyer`s patches of large intestine varied with regions and ages. But it was not found that significantly difference (p< 0.05) between different ages. Under light microscope, the number and size of the lymphoid follicles of LGC and lymphoid nodules varied with location and age. The age related increase changes in number and size of lymphoid follicles were found in the colonic PP. The width of IFAs I the rectal and colonic PP gradually increased with increasing age. The number and size of dome of rectal PP were significantly less (p<0.05) than those of other parts of the large intestine in all age groups. The biggest domes were found in the 6 month-old calves. Under the scanning electron microscope, the star-like structures of intestinal mucosa correspond with the lamina propria nodule and the LGCs related to the pit openings of intestinal mucosa. Under transmission electron microscope, the pseudopodia-like cytoplasmic protrusion were observed in the luminal surface of

Ultrastructural evaluation of bronchial lymphoid aggregates and lymphoid nodules in calves at different ages

This study was conducted with the aim of defining the ultrastructure of bronchial lymphoid aggregates and lymphoid nodules of the bronchus-associated lymphoid tissue (BALT) in 3-, 6- and 8-month-old calves. A total of 9 calves divided into 3 age groups of 3 calves in each group was used in this study. Samples of the lungs were taken systematically and processed for scanning electron microscopic (SEM) and transmission electron microscopic (TEM) examinations. The results revealed differences between the epithelium of lymphoid aggregates and lymphoid nodules. SEM showed the absence of cilia over the lymphoid nodules but not over aggregates. Flattened, non-ciliated epithelial cells which may be precursors of the M cells were found in lymphoepithelium (LPE) of 3-month-old calves over nodules. The non-ciliated epithelial cells over nodules in 6- and 8-month-old calves were columnar in bronchi, but in bronchioles they were cuboidal. However, in the 3-month-old calves, some were columnar and some flattened in bronchi and in bronchiole, they were cuboidal. Transmission electron microscopic examination showed the presence of two types of M cells found in the LPE. Type 2 M cells were found in 3- and 6-month-old calves while type I M cells predominated in the bronchi in 6- and 8-monthold calves. This work represents the first systematic investigation of the similarities and differences in the ultrastructure of lymphoid aggregates and lymphoid nodules in calves and changes therein as a function of age

Morphology of lymphoid nodules and aggregates in the lungs of calves at different ages

The present study was conducted with the aim of defining the morphology of lymphoid nodules and lymphoid aggregates in calves at different ages. A total of 9 calves, divided into 3 age groups (3-, 6- and 8-month-old) consisting of 3 calves in each group, was used in this study. Samples of the lungs were taken systematically and processed for histological examinations. The tissues were sectioned at 4, μm, stained with Haematoxylin and Eosin and examined under light microscope. The occurrence and structure of lymphoid nodules and lymphoid aggregates varied between the age groups. The number of lymphoid nodules and lymphoid aggregates in the lung of calves increased with age. The number of lymphoid nodules and lymphoid aggregates in the 8-month-old calves was significantly higher (P<0.05) than in the 3- and 6-month-old calves. Similarly, the size of lymphoid nodule and lymphoid aggregates increased with age and was significantly higher (P<0.05) in the 8-month-old calves as compared to the 3- and 6- month-old calves. The number of intraepithelial lymphocytes (IELs) within the lymphoid nodules and lymphoid aggregates was significantly higher (P<0.05) in the 8-month-old calves compared to the 3- and 6-month-old calves

Distribution and histological structure of peyer's patches in the large intestine of three-month-old calves

Distribution and histological structure of aggregated lymphoid tissues (Peyer's patches) of the large intestine were evaluated in three-month-old calves. The first patch was situated in the ileocaecal entrance, second patch in the proximal colon and third in the rectum. The length ofPeyer's patches in the proximal colon varied from 4 to 8 cm. Macroscopically, the patches at ileocaecal entrance and proximal colon were clearly seen, whereas the rectal patch was inconspicuous. Histologically, the Peyer's patches of the large intestine consisted of lymphoglandular complex and lamina propria nodules. The lymphoglandular complex was located within the submucosa that contains epithelial diverticula, which extends from muscularis mucosae. The lamina propria nodules were located in the lamina propria. The propria nodules were surrounded by wide crypts, lined by distinct follicle-associated epithelium and lacked goblet cells. The lymphoglandular complexes were covered with distinct follicle-associated epithelium with numerous intraepithelial lymphocytes and lacked goblet cells. Intraepithelial lymphocytes were distributed in the epithelial layer of the large intestine and formed a unique lymphocyte population. Some Peyer's patches ofthe large intestine were similar to that of jejunal Peyer's patches as they contained broad follicles, distinct corona areas and wide interfollicular areas

Morphological study of the jejunal and ileal Peyer's patches of three-month old calves

The current study was conducted with the aim to described the light and electron microscopic features of jejunal and ileal Peyer`s patches of three-month old calves. The samples of jejunum and ileum portion of small intestine of three-month old calves were taken and processed for light microscopic, scanning electron microscopy and transmission electron microscopy examinations. Histologically, jejunal Peyer`s patches were characterized by pear-shaped lymphoid follicles with large dome and interfollicular area. Ileal Peyer`s patches were composed of long sac like follicles with poor developed interfollicular area and an inconspicuous corona. The Follicle Associated Epithelium (FAE) is composed of absorptive epithelial cells or enterocytes and intraepithelial lymphocytes but lack of goblet cells and specialized cells or membranous cells (M cell). The jejunal Peyer`s patches consist more intraepithelial lymphocytes than that of the ileal peyer`s patches. The number of intraepithelial lymphocyte was significantly higher (p<0.05) in villi than those of crypts. Most of the intraepithelial lymphocytes were found in the subnuclear position below the nuclear level of the enterocytes. Electron microscopic examination revealed that the FAE of jejunal Peyer`s patches had scattered membranous cells or microfolds (M cells). M cells of jejunal Peyer`s patches were columnar shaped with luminal surface that bulged toward the intestinal lumen. M cells of dome epithelium of small intestine in calves were covered by blunt microvilli that were irregular, short and thick. These microvilli differed from microvilli of absorptive epithelial cells (enterocytes). Membranous bound particles were found in the dome epithelium of jejunal and ileal Peyer`s patches

Age Related Changes in Hematological Values of Myanmar Local Puppies

The hematological parameters were used to monitor the health status and its components also changed according to the ages. However, there were no reports for this issues in Myanmar local dogs. Thus, this study was carried out to investigate the age-related changes on the hematological parameters of local puppies in Myanmar. Ten local puppies with the age of 2-3 month old were used in this experiment, which was lasted for 8 weeks.The daily clinical examinations were conducted throughout the entire experimental period for general health check-up. Haematological parameters (Total WBC count and its differential counts, and RBC, HCT, MCV, HGB, MCH, MCHC and platelets) were measured bi-weekly with Abacus Vet-5 automate haematology analyser. According to the results, the total WBC and eosinophil counts were not significantly different (P&gt;0.05), while lymphocytes, monocytes, neutrophils and basophils were significantly different (P&lt;0.05) with the aging of experimental animals. The values of RBC, HGB, HCT, MCV, MCH, MCHC and platelets were not significantly different (P&gt;0.05) throughout the experimental periods. Thus, the age-related changes were observed on cell counts of lymphocytes, monocytes, neutrophils, basophils in Myanmar local puppies

Gestational diabetes mellitus and retinal microvasculature.

BACKGROUND: Small-vessel dysfunction may be an important consequence of chronic hyperglycemia. We examined the association between gestational diabetes mellitus (GDM), a state of transient hyperglycemia during pregnancy, and retinal microvascular changes in pregnant women at 26-28 weeks of pregnancy. METHODS: A total of 1136 pregnant women with singleton pregnancies were recruited during their first trimester at two major Singapore maternity hospitals in an on-going birth cohort study. Participants underwent an oral glucose tolerance test and retinal imaging at 26-28 weeks gestation (n = 542). We used the 1999 World Health Organization (WHO) criteria to define GDM: ≥7.0 mmol/L for fasting glucose and/or ≥7.8 mmol/L for 2-h post-glucose. Retinal microvasculature was measured using computer software (Singapore I Vessel Analyzer, SIVA version 3.0, Singapore Eye Research Institute, Singapore) from the retinal photographs. RESULTS: In a multiple linear regression model adjusting for age, ethnicity and maternal education, mothers with GDM had narrower arteriolar caliber (-1.6 μm; 95% Confidence Interval [CI]: -3.1 μm, -0.2 μm), reduced arteriolar fractal dimension (-0.01 Df; 95% CI: -0.02 Df, -0.001 Df;), and larger arteriolar branching angle (1.8°; 95% CI: 0.3°, 3.3°) than mothers without GDM. After further adjusting for traditional risks of GDM, arteriolar branching angle remained significantly larger in mothers with GDM than those without GDM (2.0°; 95% CI: 0.5°, 3.6°). CONCLUSIONS: GDM was associated with a series of retinal arteriolar abnormalities, including narrower caliber, reduced fractal dimension and larger branching angle, suggesting that transient hyperglycemia during pregnancy may cause small-vessel dysfunction

PAX6 Haplotypes Are Associated with High Myopia in Han Chinese

Author name used in this publication: Maurice K. H. Yap2010-2011 > Academic research: refereed > Publication in refereed journalpublished_fina

Study protocol: a double blind placebo controlled trial examining the effect of domperidone on the composition of breast milk [NCT00308334]

BACKGROUND: Domperidone, a drug that enhances upper gastric motility, is an anti-dopaminergic medication that also elevates prolactin levels. It has been shown to safely increase the milk supply of lactating women. To date, researchers have analyzed the effects of domperidone on lactating woman with respect to the quantity of their milk production, adverse effects, and drug levels in the breast milk. However, the effect of domperidone on the macronutrient composition of breast milk has not been studied and current guidelines for fortification of human milk for premature infants do not distinguish between those women using or those not using domperidone. The purpose of this study is to evaluate the effect of domperidone (given to lactating mothers of very preterm infants) on the macronutrient composition of breast milk. METHODS/DESIGN: Mothers of infants delivered at less than 31 weeks gestation, who are at least 3 weeks postpartum, and experiencing lactational failure despite non-pharmacological interventions, will be randomized to receive domperidone (10 mg three times daily) or placebo for a 14-day period. Breast milk samples will be obtained the day prior to beginning treatment and on days 4, 7 and 14. The macronutrient (protein, fat, carbohydrate and energy) and macromineral content (calcium, phosphorus and sodium) will be analyzed and compared between the two groups. Additional outcome measures will include milk volumes, serum prolactin levels (measured on days 0, 4, and 10), daily infant weights and breastfeeding rates at 2 weeks post study completion and at discharge. Forty-four participants will be recruited into the study. Analysis will be carried out using the intention to treat approach. DISCUSSION: If domperidone causes significant changes to the nutrient content of breast milk, an alteration in feeding practices for preterm infants may need to be made in order to optimize growth, nutrition and neurodevelopment outcomes

Genome-wide association study for refractive astigmatism reveals genetic co-determination with spherical equivalent refractive error : the CREAM consortium

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