Diagnostic value of bone marrow cell morphology in visceral leishmaniasis-associated hemophagocytic syndrome:Two case reports

BACKGROUND Visceral leishmaniasis related-hemophagocytic lymphohistiocytosis(VL-HLH)is a hemophagocytic syndrome caused by Leishmania infection.VL-HLH is rare,especially in nonendemic areas where the disease is severe,and mortality rates are high.The key to diagnosing VL-HLH is to find the pathogen;therefore,the Leishmania must be accurately identified for timely clinical treatment.CASE SUMMARY We retrospectively analyzed the clinical data,laboratory examination results,and bone marrow cell morphology of two children with VL-HLH diagnosed via bone marrow cell morphology at Kunming Children’s Hospital of Yunnan,China.Both cases suspected of having malignant tumors at other hospitals and who were unresponsive to treatment were transferred to Kunming Children’s Hospital.They are Han Chinese girls,one was 2 years old and the other one is 9 mo old.They had repeated fevers,pancytopenia,hepatosplenomegaly,hypertriglyceridemia,and hypofibrinogenemia over a long period and met the HLH-2004 criteria.Their HLH genetic test results were negative.Both children underwent chemotherapy as per the HLH-2004 chemotherapy regimen,but it was ineffective and accompanied by serious infections.We found Leishmania amastigotes in their bone marrow via morphological examination of their bone marrow cells,which showed hemophagocytic cells;thus,the children were diagnosed with VL-HLH.After being transferred to a specialty hospital for treatment,the condition was well-controlled.CONCLUSION Morphological examination of bone marrow cells plays an important role in diagnosing VL-HLH.When clinically diagnosing secondary HLH,VL-HLH should be considered in addition to common pathogens,especially in patients for whom HLH-2004 chemotherapy regimens are ineffective.For infants and young children,bone marrow cytology examinations should be performed several times and as early as possible to find the pathogens to reduce potential misdiagnoses.

Special IgD-λtype multiple myeloma based on bone marrow cell morphology:A case report

We aimed to explore the changes of laboratory indexes of IgD-λtype multiple myeloma with special cell morphology,and to improve the cognition of IgD-λtype MM.To explore the changes of laboratory indexes of IgD-λtype 1 multiple myeloma with special cell morphology,and to improve the cognition of IgD-λtype MM.The morphology of bone marrow cells,immunofixation electrophoresis,serum free light chain(sFLC)and other detection indexes of a patient with IgD-λtype MM treated in Handan Central Hospital in December 2020 were analyzed.The patient bone marrow smears showed 62%of abnormal cells-which were distributed in clusters and resembled lymphoma and metastatic cancer cells.The Flowcytometry indicates that the cell is a plasma cell tumor.Immunoglobulin IgG,IgA and IgM were all lower than the normal range.There is a monoclonal light chainλcomponent in immunofixation electrophoresis.The serum free light chainλwas 2700.00 mg/L,light chain k/λis 0.0023,the high of serum calcium,LDH,β2 microglobulin.IgD-λtype MM is a rare type of MM.The age of onset is young,the invasiveness is strong,the prognosis is poor,the clinical manifestation is complex,and it is easy to be misdiagnosed or missed.The analysis of the clinical symptoms and laboratory characteristics of the disease plays a positive role in the diagnosis,treatment and prognosis of the disease.

Comparison of Cell Morphology and Flow Cytometry in the Diagnosis of Multiple Myeloma

Objective: To investigate the value of cell morphology and flow cytometry in the diagnosis of Multiple myeloma (MM). Methods: 166 newly diagnosed MM patients were retrospectively analyzed, and the proportion of plasma cells detected by flow cytometry and cell morphology in these patients was statistically analyzed. Results: All patients were divided into three groups according to the proportion of plasma cells detected by cell morphology: group A (≥30%), group B (≥10% and <30%), and group C (<10%). 1) In all patients and group A, B and C, the proportion of plasma cells detected by cell morphology was all correlated with that detected by flow cytometry. 2) The proportion of plasma cells detected by cell morphology in group A and group B was higher than that by flow cytometry, while there was no significant difference in group C. 3) The sensitivity of plasma cells detected by flow cytometry in group A, B and C was 88.7%, 51.2% and 10%, respectively. 4) According to the immunophenotypic analysis, the immunophenotypic characteristics were similar, all of them were CDl9 - CD38 + CDl38 + CD56 +/- CD45dim ~ -. Conclusion: There is a certain correlation between the two detection methods. The quantitative detection of myeloma cells by cell morphology is better, and the qualitative detection by flow cytometry is better. Combined with the two detection methods, the detection rate of multiple myeloma can be significantly improved.

Multiple Myeloma: Modification and Adaptation of Plasma Cell Morphology Algorithm for the Prognosis of Congolese Patient

Objectives: To determine the multiple myeloma (MM) prognostic formulas applicable in Congolese with many aberrant and/or immature plasma cells according to GOASGUEN’s plasma cell morphology algorithm (PMA). Methods: The prospective, observational and descriptive study was carried out at the Ngaliema Clinic in Kinshasa from July 2016 to December 2019. The variables studied were the plasma cell types and the prognosis groups according to GOASGUEN and ZANDECKI. The nucleolus, the chromatin and the N/C ratio of 2 for each plasma cell encountered in multiple myeloma are examined in order by asking three successive questions as follows: 1) Is the nucleolus present? If yes, we denote 1;if not, note 0;2) Is the chromatin thin? If yes, we score 1;if not we score 0;3) The N/C ratio is greater than 6, if so, 1 is noted;if not, we note 0. We obtain a number with 3 successive digits preceded by the letter P for each plasma cell. Results: The overall rate of immature plasma cells and aberrant plasma cells in MM among Congolese was high at 26.6%. Their integration in the prognostic formulas showed for group A" = 22 patients, group B" = 5 patients and group C" = 32 patients. Examination of plasma cell types in the deceased showed that 14/17 had a P001 plasma cell count ≥ 15%. Conclusion: The high rate of aberrant and/or immature plasma cells, the P001 plasma cell type at a rate ≥ 15%, found mostly in group C" with poor prognosis, are responsible for the aggressive nature of MM in Congolese Blacks.

Regulation of cell morphology and viability using anodic aluminum oxide with custom-tailored structural parameters

Anodic aluminum oxide(AAO)with independently controlled period,porosity,and height is used as the model surface to study the single structural parameter effect on breast cancer cell behaviors,including cell polarity and cell viability.It is found that the quantity of multipolar cells and cell viability increases as the nanodent period increases from 100 to 300 nm,while the number of bipolar cells has almost no change until there is a dramatic decrease as the period increases to 3oo nm.After anodizing nanodents into nanopores,the numbers of both bipolar cells and the cell viability increase significantly with the porosity increase.However,as the porosity further increases and the nanopore changes into a nanocone pillar,most of the cells become nonpolar spheres and the cell viability decreases.Increasing the height of the nanocone pillar has little effect on the cell polarity;the cell viability increases slightly with the increase of the nanocone pillar height.These results reveal the influence of individual nanostructure parameters on the cell behavior,especially the cell polarity and the cell viability,which can help to design the surface to make the cell grow as desired.

Glycyrrhizic Acid-Loaded Poly-ɛ-Caprolactone Nanoparticles Decrease PRRSV Infection in MARC-145 Cells

Porcine reproductive and respiratory syndrome (PRRS) is an economically devastating disease with worldwide distribution caused by Betaarterivirus suid (PRRSV). The virion has great genetic and antigenic variability with a marked increase in virulence. Vaccines tested to date have been of little use in controlling the problems caused by PRRSV, so the present study was conceived to evaluate the antiviral effect of polymeric nanoparticles (PNPs) made with glycyrrhizic acid (GA). Recent work has proven that this nanoparticle system is stable. These nanoparticles have good GA carrying capacity, a size < 250 nm, a spherical morphology, and a wide safety range. The integrity of cell morphology can be maintained for up to 72 h. The antiviral effect of this nanoparticle system was tested in cultures of MARC-145 cells in pre- and coinfection assays with PRRSV to evaluate changes in cell morphology and effects on cell viability. The use of PNPsGA with the real-time quantitative polymerase chain reaction (RT-qPCR) decreased viral infection by 38% in 3 amplification cycles. These results suggest that this system has an antiviral effect against PRRSV under the study conditions established.

Laser processing effects on Ti−45Nb alloy surface,corrosive and biocompatible properties

The Ti−45Nb(wt.%)alloy properties were investigated in relation to its potential biomedical use.Laser surface modification was utilized to improve its performance in biological systems.As a result of the laser treatment,(Ti,Nb)O scale was formed and various morphological features appeared on the alloy surface.The electrochemical behavior of Ti−45Nb alloy in simulated body conditions was evaluated and showed that the alloy was highly resistant to corrosion deterioration regardless of additional laser surface modification treatment.Nevertheless,the improved corrosion resistance after laser treatment was evident(the corrosion current density of the alloy before laser irradiation was 2.84×10^(−8)A/cm^(2),while that after laser treatment with 5 mJ was 0.65×10^(−8)A/cm^(2))and ascribed to the rapid formation of a complex and passivating bi-modal surface oxide layer.Alloy cytotoxicity and effects of the Ti−45Nb alloy laser surface modification on the MRC-5 cell viability,morphology,and proliferation were also investigated.The Ti−45Nb alloy showed no cytotoxic effect.Moreover,cells showed improved viability and adherence to the alloy surface after the laser irradiation treatment.The highest average cell viability of 115.37%was attained for the alloy laser-irradiated with 15 mJ.Results showed that the laser surface modification can be successfully utilized to significantly improve alloy performance in a biological environment.

Biocompatibility evaluation in vitro. Part I: Morphology expression and proliferation of human and rat osteoblasts on the biomaterials

The biocompatibility evaluation of calcium phosphate based biomaterials is performed by tissue culture in vitro model. Three kinds of bioceramic materials which are potential to deal with bone trauma and/or conduct tissue growth are recommodated. The biological research results show that human and animal osteoblast cells anchor the materials surface in two hours in culture. Confocal laser scanning microscopy (CLSM) demonstrated the normal cell distribution and proliferation on both of dense and porous biomaterials. Hydroxyapatite and tricalcium phosphate stimulate cell proliferation. However, DNA and protein synthesis were considerably limited and the apoptosis phenomenon would be present on the hydroxyapatite (HA) materials by adding Al, Mg elements. Several important methods of biocompatibility evaluation of implant materials are described and the related biological molecular techniques such as tissue culture, cell transfection, cellular DNA stain, and Lowry assay are involved in the present research.

Evaluation of somatic embryo production during embryogenic tissue proliferation stage using morphology,maternal genotype,proliferation rate and tissue age of Pinus thunbergii Parl

To determine the optimal embryogenic capacity(somatic embryo production)of the selected elite nematode-resistant genotypes of Pinus thunbergii,variables such as embryogenic tissue(ET)morphology,maternal genotype,proliferation rate and tissue age were analyzed.ET morphology and histological evaluation of the proliferation stage showed a decrease in filamentous clump and protuberant surfaces and a decline in the acetocarmine-staining area,which indicates a decrease in somatic embryo production(SEP).Variations in cell physiology during the prolifera-tion stage showed that SEP was positively correlated with soluble sugars and proteins,but negatively correlated with starch,peroxidase,and superoxidase.In addition,SEP was significantly(p<0.001)affected by maternal genotype,tis-sue age and proliferation rate.Moreover,SEP was positively correlated with proliferation rate(r=0.98,p<0.001),but negatively correlated with tissue age(r=−0.95,p<0.001).In general,the results suggest that SEP could be assessed in ET proliferation stages by the apparent cell morphology,histology,proliferation rate and tissue age,which provides novel insights for evaluating the ET maturation capacity(number of somatic embryos)during the proliferation stage of P.thunbergii somatic embryogenesis.

Migration and shape of cells on different interfaces

Impacts of microenvironments on cell migration have been reported in various interaction modes.A rapid tumor metastasis occurs along topological interfaces in vivo,such as the interface between the blood vessels and nerves.In this work,we culture MDA-MB231 cells at dish-liquid,dish-hydrogel,and hydrogel-liquid interfaces,respectively,to study how these different interfaces influence cell dynamics and morphology.Our results show that the migration mode of cells changes from an amoeboid motion to a mesenchymal motion but their speed do not change obviously if the interface changes from hydrogel-liquid to dish-liquid.In contrast,the migration mode of cells at a dish-hydrogel interface maintains as a mesenchymal motion,whereas their speed increases significantly.

Effects of Low-Intensity Ultrasound on Cell Proliferation and Reproductivity

Ultrasound has been widely used in clinics. Cellular responses to low-intensity ultrasound are parameter-dependent. Proper parameter setting is vital to its exact use. To get guidelines for parameter setting, lowintensity ultrasound stimulation on the proliferation and reproductivity of Hep G2 and 3T3 cells in vitro was examined with a 1.06 MHz-generator by changing the parameters(including intensity, pulse repetition frequency and duty cycle)in a wide range. Cell viability and reproductivity at different time after sonication were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)and colony formation assay to indicate timerelated proliferation. The results illustrate that ultrasound irradiation at 0.4—0.8 W/cm^2 and high pulse repetition frequency(100 Hz)can facilitate cell proliferation, while above 0.8 W/cm^2 would resist it. The extent of resistance closely correlated with duty cycle and pulse repetition frequency. Resistance effect at low pulse repetition frequency(1 Hz)is greater than that at high pulse repetition frequency(100 Hz)and not time-related. The influence of high pulse repetition frequency is time-accumulated, indicating cellular process involved. These findings would provide valuable guidelines for the application of low-intensity ultrasound in stem cell transformation and tissue engineering.

Effects of Nano-TiO2 on Chlamydomonas reinhardtii Cell Surface under UV,Natural Light Conditions

Cell surface of aquatic organisms constitutes a primary site for the interaction and a barrier for the nano-TiO2 biological effects.In the present study,the biological effects of nano-TiO2 on a unicellular green algae Chlamydomonas reinhardtii were studied by observing the changes of the cell surface morphology and functional groups under UV or natural light.By SEM,the cell surface morphology of C.reinhardtii was changed under UV light,nano-TiO2 with UV light or natural light,which indicated that photocatalysis damaged cell surface.It was also observed that cell surface was surrounded by TiO2 nanoparticles.The ATR-FTIR spectra showed that the peaks of functional groups such as C-N,-C=O,-C-O-C and P=O,which were the important components of cell wall and membrane,were all depressed by the photocatalysis of nano-TiO2 under UV light or natural light.The photocatalysis of nano-TiO2 promoted peroxidation of functional groups on the surface of C.reinhardtii cells,which led to the damages of cell wall and membrane.

Differences in energy and corneal endothelium between femtosecond laser-assisted and conventional cataract surgeries：prospective,intraindividual,randomized controlled trial

AIM： To compare intraoperative phacoemulsification parameters and its effect on the corneal endothelium of eyes undergoing femtosecond laser-assisted cataract surgery（FLACS） versus conventional phacoemulsification（CP） cataract surgery.METHODS： Two hundred eyes from one hundred patients were included in a prospective, non-blinded, randomized, controlled, intraindividual clinical study. One hundred eyes underwent FLACS while their one hundred fellow eyes underwent CP. All surgeries were performed using the Victus？ femtosecond laser platform and Infinity？ Vision System phacoemulsification machine. Primary outcome measure was endothelial cell density 6 mo after surgery. Secondary outcome measures included central corneal thickness（CCT）, average cell area, standard deviation, coefficient of variation and hexagonality before surgery and 6 mo after surgery and endothelial cell density loss during this period were also evaluated. Intraoperative efficiency parameters [cumulative dissipated energy（CDE）, total intraocular surgery time, total ultrasound time, total phacoemulsification time, total torsional energy time, total aspiration time, ultrasound energy, torsional amplitude and fluid required during surgery] were also collated. RESULTS： Data from these patients was not considered for analysis. Data from 92 patients were analysed. Postoperative endothelial cell density（cells/mm2） between groups（2211.88±392.49 CP; 2246.31±403.48 FLACS） was not statistically significant（P=0.869）. Total ultrasound time, torsional energy time, CDE and fluid requirements were significantly lower the FLACS group（P〈0.05）. Other parameters did not show statistically significant difference between FLACS and CP.CONCLUSION： FLACS displays significant improvements in phacoemulsification parameters in comparison to CP. There are no significant differences in corneal endothelium measures between FLACS and CP.

Growth inhibitory response and ultrastructural modification of oral-associated candidal reference strains (ATCC) by Piper betle L. extract

Candida species have been associated with the emergence of strains resistant to selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease mucosal fungal infections. This study aimed to investigate the effects of Piper betle extract on the growth profile and the ultrastructure of commonly isolated oral candidal cells. The major component of Po betle was identified using liquid chromatography-mass spectrophotometry （LC-MS/MS）. Seven ATCC control strains of Candida species were cultured in yeast peptone dextrose broth under four different growth environments： （i） in the absence of P. betle extract; and in the presence of P. beUeextract at respective concentrations of （ii） 1 mg.mL-1; （iii） 3 mg.mL-1; and （iv） 6 mg.mL- 1 The growth inhibitory responses of the candidal cells were determined based on changes in the specific growth rates （μ）. Scanning electron microscopy （SEM） was used to observe any ultrastructural alterations in the candida colonies. LC-MS/MS was performed to validate the presence of bioactive compounds in the extract. Following treatment, it was observed that the p-values of the treated cells were significantly different than those of the untreated cells （P〈0.05）, indicating the fungistatic properties of the P. beUe extract. The candidal population was also reduced from an average of 13.44× 10^6 to 1.78×10^6 viable cell counts （CFU）.mL-1, SEM examination exhibited physical damage and considerable morphological alterations of the treated cells. The compound profile from LC-MS/MS indicated the presence of hydroxybenzoic acid, chavibetol and hydroxychavicol in P. betle extract. The effects of P. betle on candida cells could potentiate its antifungal activity.

Experiment and simulation of foaming injection molding of polypropylene/nano-calcium carbonate composites by supercritical carbon dioxide

Microcellular injection molding of neat isotactic polypropylene(iPP) and isotactic polypropylene/nano-calcium carbonate composites(i PP/nano-CaCO_3) was performed using supercritical carbon dioxide as the physical blowing agent. The influences of filler content and operating conditions on microstructure morphology of i PP and i PP/nano-CaCO_3 microcellular samples were studied systematically. The results showed the bubble size of the microcellular samples could be effectively decreased while the cell density increased for i PP/nano-CaCO_3 composites, especially at high CO_2 concentration and back pressure, low mold temperature and injection speed, and high filler content. Then Moldex 3D was applied to simulate the microcellular injection molding process, with the application of the measured ScCO_2 solubility and diffusion data for i PP and i PP/nano-Ca CO_3 composites respectively. For neat i PP, the simulated bubble size and density distribution in the center section of tensile bars showed a good agreement with the experimental values. However, for i PP/nano-CaCO_3 composites, the correction factor for nucleation activation energy F and the pre-exponential factor of nucleation rate f_0 were obtained by nonlinear regression on the experimental bubble size and density distribution. The parameters F and f_0 can be used to predict the microcellular injection molding process for i PP/nano-CaCO_3 composites by Moldex 3D.

Fabrication of mixed perovskite organic cation thin films via controllable cation exchange

Here in this paper, we demonstrate a facile technique for creating the mixed formamidinium（HN = CHNH_3~＋, FA~＋）and methylammonium（CH_3NH_3~＋, MA~＋） cations in the lead iodide perovskite. This technique entails a facile drop-casting of formamidinium iodide（FAI） solutions on as-prepared MAPbI_3 perovskite thin films under the controlled conditions,which leads to controllable displacement of the MA~＋ cations by FA~＋ cations in the perovskite structure at room temperature. Uniform and controllable mixed organic cation perovskite thin films without a ＂bi-layered＂ or graded structure are achieved. By applying this approach to photovoltaic devices, we are able to improve the performances of devices through extending their optical-absorption onset further into the infrared region to enhance solar-light harvesting. Additionally,this work provides a simple and efficient technique to tune the structural, electrical, and optoelectronic properties of the light-harvesting materials for high-performance perovskite solar cells.

Effects ofm perioperative cimetidine administration on tumor cell nuclear morphology and DNA content in patients with gastric and colorectal cancer

Objective To explore the effects of perioperative cimetidine administration on tumor cell nuclear morphometric parameters and DNA content in patients with gastric and colorectal adenocarcinoma (GCRA) Past studies have attributed the antitumor effect of cimetidine to its immunomodulatory property, which led to an increase of cellular immunity Whether there are other possible mechanisms by which cimetidine exerts its antitumor function is unknown 49 patients with GCRA were randomized into treatment group (n=25) and control group (n=24) based on whether cimetidine was applied to them during the perioperative periold The treatment group started oral cimetidine intake 400mg, tid, 7-10d before oiperation, followed by curative surgery 'The control group did not receive cimetidine Tumor specimens were paraffin embedded for 4μm thick microsection and stained with (1) hematoxylin and eosin (HE) for the morphometric measurements of tumor cell nuclear area (NA), nuclear perimeter (NP), maximal nuclear diameter (MMND) and minimal nuclea4r diameter (MNND); (2) feulgen stain for tumor nuclear DNA content analysis by IBAS Image Analyzer The percentages (%) of diploidy (2C), tripletetraploidy (3C 4C), quintuple ploidy (5C) and >quintuple ploidy (>5C) tumor cells were calculated, using the mean value of DNA content of 50 lymphocytes as normal 2C control 3C 5C cells were designated as law aneuploid cells and >5C cells as high aneupoid cells Results The clinicopathological variables between the two groups were balanced and comparable There were no statistically significant differences between bthe treatment and control groups in regard of the following parameters: age, gender, tumor location, pathological type, TNM stage, and degree of differentiation The NA (μm 2), NP (μm), MMND (μm) and MNND (μm) for treatm ent group/control group were 23 54±5 08/34 698±10 18 ( P <0 001), 22 06±4 43/24 88±4 05 ( P <0 05),7 84±1 64/8 62±1 24 ( P >0 05), and 4 42±0 61/5 41±0 89 ( P <0 001), respectively The percentages (%) of 2C, 3C 4C, 5C and >5C tumor cells for treatment group/control group were 16 64±2 58/5 35±2 14 ( P <0 002), 39 84±2 28/35 70±3 58 ( P >0 50), 12 42±5 00/14 48±0 74 ( P >0 20), 31 11±6 86/45 97±3 82 ( P <0 005), respectively In the treatment group, there was a tendency tiowards low aneuploid tumor cells from high an euploid tumor cells However, high aneuploid tumor cells predominated in the control group Conclusion Perioperative administration of cimetidine to GCRA patients could decrease the size of tumor cell nuclei, raise the percentage of diploid tumor cells, and partially convery high aneuploid tumor cells into low aneuploid tumor cells All of these effects may in turn help reduce the proliferative potential and invasiveness of tumor cells The direct inhibitory functions on tumor cell nuclei may be a new antitumor mechanism of cimetidine, in addition to its immunomodulatory action

An Image Skeletonization-Based Tool for Pollen Tube Morphology Analysis and Phenotyping

The mechanism underlying pollen tube growth involves diverse genes and molecular pathways. Alterations in the regulatory genes or pathways cause phenotypic changes reflected by cellular morphology, which can be captured using fluorescence microscopy. Determining and classifying pollen tube morphological phenotypes in such microscopic images is key to our understanding the involvement of genes and pathways. In this context, we propose a computational method to extract quantitative morphological features, and demonstrate that these features reflect morphological differences relevant to distinguish different defects of pollen tube growth. The corresponding software tool furthermore includes a novel semi-automated image segmentation approach, allowing to highly accurately identify the boundary of a pollen tube in a microscopic image.

Pefabloc- A sulfonyl fluoride serine protease inhibitor blocks induction of Diotericin in Drosoohila 1（2）mbn cells

Insects protect themselves against microbial infection by an efficient innate immune system that is activated by recognition ofinvariant microbial surface molecules. In the fruit fly Drosophila melanogaster the presence of bacteria is associated with expression of antimicrobial peptides in host immune-competent tissues. Host receptors detect infection and relay the signal to mount the appropriate immune response. In Drosophila hemocyte- like l（2）mbn cells pre-infection treatment with Pefabloc, a commonly used serine protease inhibitor, induced two major effects： it blocked expression of the antibacterial peptide Diptericin in response to live Gram-negative bacteria and bacterial surface molecules （crude lipopolysaccharide contaminated by peptidoglycans） and it induced morphological changes.

Morphological properties of medial amygdala-projecting retinal ganglion cells in the Mongolian gerbil

The amygdala is a limbic structure that is involved in many brain functions, including emotion, learning and memory. It has been reported that melanopsin-expressing retinal ganglion cells(ip RGCs) innervate the medial amygdala(Me A). However, whether conventional RGCs(c RGCs) project to the Me A remains unknown. The goal of this study was to determine if c RGCs project to the Me A and to determine the morphological properties of Me A-projecting RGCs(Me A-RGCs). Retrogradely labeled RGCs in whole-mount retinas were intracellularly injected to reveal their dendritic morphologies. Immunohistochemical staining was performed to selectively label ip RGCs(Me A-ip RGCs) and c RGCs(Me A-c RGCs). The results showed that 95.7% of the retrogradely labeled cells were c RGCs and that the rest were ip RGCs. Specifically, Me A-c RGCs consist of two morphological types. The majority of them exhibit small but dense dendritic fields and diffuse ramification patterns as previously reported in RG_(B2)(95%), while the rest exhibit small but sparse dendritic branching patterns resembling those of RG_(B3) cells(5%). Me Aip RGCs consist of M1 and M2 subtypes. The Me A-RGCs showed an even retinal distribution patterns. The soma and dendritic field sizes of the Me A-RGCs did not vary with eccentricity. In conclusion, the present results suggest that Me A-RGCs are structurally heterogeneous. These direct RGCs that input to the Me A could be important for regulating amygdala functions.