[Expression of GPNMB in renal eosinophilic tumors and its value in differential diagnosis].

Objective: To investigate the expression of glycoprotein non metastatic melanoma protein B (GPNMB) in renal eosinophilic tumors and to compare the value of GPNMB with CK20, CK7 and CD117 in the differential diagnosis of renal eosinophilic tumors. Methods: Traditional renal tumor eosinophil subtypes, including 22 cases of renal clear cell carcinoma eosinophil subtype (e-ccRCC), 19 cases of renal papillary cell carcinoma eosinophil subtype (e-papRCC), 17 cases of renal chromophobe cell carcinoma eosinophil subtype (e-chRCC), 12 cases of renal oncocytoma (RO) and emerging renal tumor types with eosinophil characteristics [3 cases of eosinophilic solid cystic renal cell carcinoma (ESC RCC), 3 cases of renal low-grade eosinophil tumor (LOT), 4 cases of fumarate hydratase-deficient renal cell carcinoma (FH-dRCC) and 5 cases of renal epithelioid angiomyolipoma (E-AML)], were collected at the Affiliated Drum Tower Hospital of Nanjing University Medical School from January 2017 to March 2022. The expression of GPNMB, CK20, CK7 and CD117 was detected by immunohistochemistry and statistically analyzed. Results: GPNMB was expressed in all emerging renal tumor types with eosinophil characteristics (ESC RCC, LOT, FH-dRCC) and E-AML, while the expression rates in traditional renal eosinophil subtypes e-papRCC, e-chRCC, e-ccRCC and RO were very low or zero (1/19, 1/17, 0/22 and 0/12, respectively); the expression rate of CK7 in LOT (3/3), e-chRCC (15/17), e-ccRCC (4/22), e-papRCC (2/19), ESC RCC (0/3), RO (4/12), E-AML(1/5), and FH-dRCC (2/4) variedly; the expression of CK20 was different in ESC RCC (3/3), LOT(3/3), e-chRCC(1/17), RO(9/12), e-papRCC(4/19), FH-dRCC(1/4), e-ccRCC(0/22) and E-AML(0/5), and so did that of CD117 in e-ccRCC(2/22), e-papRCC(1/19), e-chRCC(16/17), RO(10/12), ESC RCC(0/3), LOT(1/3), E-AML(2/5) and FH-dRCC(1/4). GPNMB had 100% sensitivity and 97.1% specificity in distinguishing E-AML and emerging renal tumor types (such as ESC RCC, LOT, FH-dRCC) from traditional renal tumor types (such as e-ccRCC, e-papRCC, e-chRCC, RO),respectively. Compared with CK7, CK20 and CD117 antibodies, GPNMB was more effective in the differential diagnosis (P<0.05). Conclusion: As a new renal tumor marker, GPNMB can effectively distinguish E-AML and emerging renal tumor types with eosinophil characteristics such as ESC RCC, LOT, FH-dRCC from traditional renal tumor eosinophil subtypes such as e-ccRCC, e-papRCC, e-chRCC and RO, which is helpful for the differential diagnosis of renal eosinophilic tumors.

Ocnus is essential for male germ cell development in Drosophila melanogaster.

The ocnus (ocn) gene encodes a protein abundant in the testes, implying its role in testis development. When Drosophila melanogaster is infected with the endosymbiont wMel Wolbachia, which affects the spermatogenesis of its hosts, ocn is downregulated in the third-instar larval testes, suggesting a role of ocn in spermatogenesis. In this study, we knocked down ocn in the testes and found that the hatch rates of embryos derived from ocn-knockdown males were significantly decreased, and 84.38% of the testes were much smaller in comparison to controls. Analysis of the smaller testes showed no germ cells but they had an extended hub. Using RNA-sequencing (RNA-Seq), we identified 69 genes with at least a twofold change (q-value < 5%) in their expression after ocn knockdown; of these, eight testes-specific and three reproduction-related genes were verified to be significantly downregulated using quantitative reverse transcription-PCR. Three genes (orientation disruptor, p24-2 and CG13541) were also significantly downregulated in the presence of Wolbachia. Furthermore, 98 genes were not expressed when ocn was knocked down in testes. These results suggest that ocn plays a crucial role in male germ cell development in Drosophila, possibly by regulating the expression of multiple spermatogenesis-related genes. Our data provide important information to help understand the molecular regulatory mechanisms underlying spermatogenesis.

Identification of risk factors of Coxiella burnetii (Q fever) infection in veterinary-associated populations in southern Taiwan.

The first case of Q fever in Taiwan was reported in 1993. The disease is considered to be emerging in Taiwan, but the route of transmission has remained unclear. The annual number of confirmed Q fever cases has been increasing up to more than 100 cases since 2005, comparing with less than 30 before 2003. The purpose of this study was to determine the seroprevalence and risk factors of Coxiella burnetii infection in veterinary-associated populations in southern Taiwan. A total of 228 serum samples of high risk individuals engaging in veterinary-related work or animal-farm work, were collected between March and June in 2007. The study individuals were interviewed by a structured questionnaire designed for Q fever investigation. Serum samples from different animal species were also obtained for Q fever analysis in the same study areas. Serological test was conducted by indirect immunofluorescence antibody assay (IFA). The result demonstrated the overall seroprevalence of Q fever was 26.3% in individuals engaging in veterinary and animal-related work in southern Taiwan. After multiple logistic regression analysis, goat exposure was significantly associated with seropositivity of Q fever in the study population in southern Taiwan (adjusted odds ratio: 2.62; 95% CI: 1.06-6.46). In addition, the highest seroprevalence (43.8%) of Q fever was identified in goats (P < 0.05). Finally, this study documented that people with prior knowledge of Q fever were less likely to be seropositive for C. burnetii. It was concluded that goat exposure was the most important risk factor associated with C. burnetii infection and appropriate health education could be useful to prevent high risk individuals from the infection in southern Taiwan.

Crystal structure of the Atx1 metallochaperone protein at 1.02 A resolution.

BACKGROUND: Metallochaperone proteins function in the trafficking and delivery of essential, yet potentially toxic, metal ions to distinct locations and particular proteins in eukaryotic cells. The Atx1 protein shuttles copper to the transport ATPase Ccc2 in yeast cells. Molecular mechanisms for copper delivery by Atx1 and similar human chaperones have been proposed, but detailed structural characterization is necessary to elucidate how Atx1 binds metal ions and how it might interact with Ccc2 to facilitate metal ion transfer. RESULTS: The 1.02 A resolution X-ray structure of the Hg(II) form of Atx1 (HgAtx1) reveals the overall secondary structure, the location of the metal-binding site, the detailed coordination geometry for Hg(II), and specific amino acid residues that may be important in interactions with Ccc2. Metal ion transfer experiments establish that HgAtx1 is a functional model for the Cu(I) form of Atx1 (CuAtx1). The metal-binding loop is flexible, changing conformation to form a disulfide bond in the oxidized apo form, the structure of which has been solved to 1.20 A resolution. CONCLUSIONS: The Atx1 structure represents the first structure of a metallochaperone protein, and is one of the largest unknown structures solved by direct methods. The structural features of the metal-binding site support the proposed Atx1 mechanism in which facile metal ion transfer occurs between metal-binding sites of the diffusible copper-donor and membrane-tethered copper-acceptor proteins. The Atx1 structural motif represents a prototypical metal ion trafficking unit that is likely to be employed in a variety of organisms for different metal ions.