Medical Molecular Morphology最新文献

We used scanning electron microscopy to visualize the regeneration of goldfish scales on day 3 in vivo. Several vesicle-like structures of 100-700 nm diameter flowed onto the fibrous sheets in groups of spindle-shaped bodies arranged in the same direction. Transmission electron microscopy revealed that these structures were encircled by the lipid bilayer membrane. In addition, some had a small mass of high electron density. Scanning electron microscopic observations of specimens treated with bleach revealed particles of almost the same size as the observed electron-dense mass scattered between fibers, with a thickness of approximately 50 nm on day 3 of scale regeneration. The diameter of these particles increased by 5 times on day 14, sticking closely to the fibers. Furthermore, elemental analysis using electron probe microscopy showed that the particles were composed of calcium and phosphorous. These results confirmed that the spindle-shaped bodies and vesicle-like structures were osteoblasts and matrix vesicles, respectively.

Well-differentiated neuroendocrine tumor (NET) and poorly differentiated neuroendocrine carcinoma (NEC) are distinct entities with different biological behavior. However, difficult cases showing equivocal morphology have been reported in some organs. Herein, we report a case of primary hepatic neuroendocrine neoplasm (NEN) with ambiguous histopathological features admixed with conventional hepatocellular carcinoma (HCC). A 70-year-old man with untreated chronic hepatitis B underwent left medial sectionectomy because of two incidental liver masses. On pathological examination, one of the resected tumors had intermingling NEN and HCC components. The NEN component consisted of relatively uniform tumor cells proliferating in trabecular, cord-like, or solid patterns with peripheral nuclear palisading. The tumor cells were immunopositive for synaptophysin, chromogranin A, cluster of differentiation 56 (CD56), and focally hepatocyte paraffin 1. p53 showed wild-type expression. The Ki-67 labeling index was 27% at the hot spot. Eleven months after the surgery, he died of a cerebral hemorrhage without evidence of recurrent liver cancer. The intermediate degree of differentiation and the modest proliferative activity can challenge the distinction between NEC and NET G3. While the coexisting HCC indicates NEC rather than NET in a pathogenetic viewpoint, such ambiguous tumor may not be as aggressive as typical NECs.

Pemphigus vulgaris (PV) is a rare, potentially fatal, immune-mediated chronic disease characterized by the presence of bullous intraepithelial lesions on mucous membranes and skin. This study aimed to perform a systematic literature review covering PV clinical and histopathological aspects and treatment. The literature searches were carried out in the Pubmed, Periódicos Capes, Scopus, Science Direct, Web of Science and Scielo databases. Articles in English or Spanish published from 2000 to 2022 comprising case reports, case series and literature reviews with case report were included. After the analyses, 21 articles were selected. PV generally presents in the third to sixth decades of life and exhibits no gender predilection. The disease manifests itself clinically through irregular and painful blisters that rupture, resulting in erosion and ulceration areas. Histopathologically, the presence of an intraepithelial cleft located above the basal layer and acantholysis are observed. Standard treatment encompasses systemic and topical corticosteroids, with prednisolone being widely employed. Management consists of a remission induction phase and a maintenance phase. An early and accurate diagnosis is paramount to quickly initiate treatment, resulting in more favorable prognoses, as the choice of treatment and responses depend on the severity of the disease. Registered at the International Prospective Register of Systematic Reviews (PROSPERO): Number CRD42024497313.

Low-extremity ischemic disease is a common complication in diabetic patients, leading to reduced quality of life and potential amputation. This study investigated the therapeutic effect of spinal cord stimulation (SCS) on patients with diabetic foot disease and a rat model of diabetic foot injury. SCS was applied to patients with diabetic foot disease, with clinical assessments performed before and after therapy. Blood levels of NGF, BDNF, and NT-3 were determined by ELISA. A rat model of diabetic foot injury was established to validate NT-3's role in SCS therapy. SCS therapy improved the condition of patients with diabetic ischemic foot disease and promoted wound healing in the rat model. NT-3 levels significantly increased after SCS therapy in both patients and rats. Recombinant NT-3 administration improved wound healing and re-vascularization in the rat model, while NT-3 neutralization abrogated SCS's therapeutic effect. SCS improves the condition of patients with diabetic ischemic foot disease by inducing NT-3 production. Both SCS and NT-3 supplementation show therapeutic potential for ameliorating diabetic foot disease.

Dry eye, a common ocular surface disease associated with tear film instability and corneal impairment, is frequently accompanied by ocular discomfort and pain. Recent research has shown that corneal nerve dysfunction may play a role in certain pathologies of dry eye; however, the details remain unclear. To clarify the aberration in corneal nerves underlying sensory abnormalities, in addition to corneal impairment in dry eye, we examined the morphological alterations of nerve fibers in the corneas excised from guinea pigs with dry eye, where the lacrimal glands were surgically excised. Guinea pigs with dry eye exhibited reduced tear volume, increased spontaneous blink frequency, and corneal epithelial damage. Simultaneously, the subbasal nerve plexus in the cornea visualized using an anti-tubulin βIII antibody partially outgrew and became convoluted. The morphology of peptidergic nerves containing calcitonin gene-related peptide, which may function as a polymodal nociceptor, was also altered. These results indicate that guinea pigs with excised lacrimal glands can serve as useful tools for investigating the neuronal mechanisms underlying corneal pathology in dry eyes. Additionally, chronic tear deficiency may considerably alter nerve structure, including peptidergic nerves in the cornea, accompanied by epithelial damage and increased blink frequency.

We report a case of solid papillary carcinoma (SPC) that developed at the site of a previous intraductal papilloma (IDP) with atypical ductal hyperplasia. This case supports IDP as a potential precursor lesion to SPC.

Adenosquamous carcinoma (ASC) with the presence of a sarcomatous component is exceptionally uncommon in intrahepatic cholangiocarcinoma (iCCA). We report a case of hepatic ASC with rhabdoid transformation, one variation of sarcomatous change. A 72-year-old man was admitted to our hospital after being diagnosed with a 45 mm-diameter neoplastic lesion in the right hepatic duct on abdominal computed tomography. Laboratory findings showed increases in AST, ALT, ALP, gamma-GT, CA19-9 and DUPAN-II. The patient then underwent an extended right hepatectomy. Histopathologically, the tumor was composed of an ASC component within an abundant fibrous stroma and a sarcomatoid carcinoma component. By immunohistochemistry, keratin 7 and keratin 19 were expressed by all tumor cells. Expression of keratin 5/6, p40 and p63 was restricted to the squamous component. The sarcomatoid component was immunoreactive for vimentin with no loss of INI1 expression. This component also showed a loss of membranous E-cadherin expression and a reduction of membranous β-catenin expression. Staining for desmin, myoglobin and HepPar1 was negative in any tumor cells. The patient died of liver failure 3 months after surgery. This report aims to provide a better understanding of the clinicopathological characteristics and disease progression of the rare variants of iCCA to aid diagnosis and treatment.

This report presents a rare case of a 45-year-old man diagnosed with a primary hepatic alpha-fetoprotein-producing neuroendocrine neoplasm, a condition rarely reported in the literature. The patient presented with initial symptoms of back and epigastric pain, after which multiple liver lesions were discovered on contrast-enhanced computed tomography, suggesting intrahepatic cholangiocarcinoma. Histopathological and immunohistochemical analyses confirmed the diagnosis of alpha-fetoprotein-producing neuroendocrine neoplasm that was further supported by genetic testing, which revealed FGFR2 and TP53 mutations commonly encountered in intrahepatic cholangiocarcinoma. Despite receiving various chemotherapeutic regimens, the patient exhibited a progressive disease. This case underscores the importance of accurate differential diagnosis from hepatocellular carcinoma and intrahepatic cholangiocarcinoma due to differences in treatment approaches and prognoses and highlights the necessity for increased awareness of AFP-producing primary hepatic neuroendocrine neoplasms among clinicians and pathologists. It emphasizes the significance of comprehensive histopathological evaluation, immunohistochemical profiling, and genetic analysis for precise diagnosis and tailored therapeutic strategies. Further research is warranted to elucidate the molecular mechanisms underlying this rare liver tumor subtype and develop targeted treatments.

Silica nanoparticles are used in functional foods and tablets to increase drug stability and delivery. We investigated a patient with acute kidney injury with Fanconi syndrome after taking functional food tablets made from red yeast rice using low-vacuum scanning electron microscopy (LVSEM) with an element analysis system. Kidney biopsy revealed proximal tubular necrosis and vacuolization with 10-20 nm black granules, which were similar to the silica nanoparticles found in the functional food tablets and urinary samples, as determined via LVSEM with element analysis. Reabsorbed silica nanoparticles induce oxidative stress in the kidney. Element analysis by LVSEM is useful to investigate a possible cause of acute tubular necrosis in patients with Fanconi syndrome.

The aim of this study was to report transmission electron microscopic findings of a case with whole corneal descemetocele following infective corneal ulcer for the first time in literature. A 72-year-old male patient presented with infective corneal ulcer. After resolution of the infection, corneoscleral transplantation was performed. The excised very thin corneal membrane was processed for transmission electron microscopic examination. Transmission electron microscopic examination of the specimen revealed many layered structures that consisted of two different types of cells. The first type consisted of lighter staining polygonal cells, while the second consisted of elongated cells with relatively dense staining. All cells were connected with a large number of gap or adherens junctions with intercalation of the cell membranes of adjacent cells. A haphazard distribution of cytoplasmic microfilaments were also observed in all of the cell types. There was no evidence of the presence of endothelial cells throughout the specimen. There was also no evidence of Descemet membrane presence except for a small part adjacent to iris tissue that contained some melanosomes. Although we clinically diagnosed descemetocele, Descemet membrane was not present at the electron microscopic level, and thus, the expression "descemetocele" is inappropriate.