Dissociation of ferriheme from oxidized heme proteins and re-reduction of ferriheme to ferroheme are crucial for the formation of zinc protoporphyrin IX in nitrite/nitrate-free dry-cured meat products.

Zinc protoporphyrin IX (ZnPP) is the dominant red pigment in nitrate/nitrite-free dry-cured meat products such as Parma ham, and it is considered to be a potential alternative to nitrite/nitrate for reddening dry-cured meat products. Ferroheme and ferriheme dissociated from heme proteins in meat were proposed as substrates to form ZnPP. To elucidate their specific formation mechanism, nitric oxide, carbon monoxide, and azide were used to stable heme in heme proteins. The exogenous hemoglobin derivatives bound with these ligands showed lower heme dissociation compared with exogenous oxyhemoglobin and did not contribute to ZnPP formation. Meanwhile, azide inhibited almost all ZnPP formation by binding to ferriheme, indicating ferriheme dissociation from oxidized heme proteins, predominantly for ZnPP formation. Free ferriheme could not be converted to ZnPP unless it was reduced to ferroheme. Overall, ferriheme dissociated from oxidized heme proteins was the dominant substrate for conversion to ZnPP after re-reduction to ferroheme.

Zinc protoporphyrin IX predominantly exists as a complex non-enzymatically bound to apo-hemoglobin in Parma ham.

Most of the water-soluble zinc protoporphyrin IX (ZnPP) in Parma ham mainly exists as complexes with hemoglobin and myoglobin (ZnPP-Hb and ZnPP-Mb). To elucidate the formation mechanism of these complexes, a new experimental model to produce higher amount of water-soluble ZnPP complexes was established. ZnPP-Hb was detected as the main water-soluble ZnPP complex in this model, which is the same as that in Parma ham. Adding exogenous Hb into this model promoted higher ZnPP formation than with Mb added, indicating that Hb was the superior substrate for generating ZnPP compared to Mb. The increase in non-heme iron content with ZnPP formation in both the Hb- and Mb-added groups indicated that the release of iron ion from heme was a crucial step in ZnPP formation. ZnPP-Hb was formed when ZnPP non-enzymatically bound with apo-Hb. These results revealed the mechanism of why ZnPP-Hb is more dominant in Parma ham than to ZnPP-Mb.

Direct Photometric Assay for Copper Chlorophyll Adulterants in Edible Oil by the Aid of an Ultraviolet-Photobleaching Pretreatment.

Adulterating edible oil with copper chlorophyll derivatives (E141i) has made a substantial impact on the edible oil industry and food safety. This study demonstrates an efficient and reliable screening method to directly identify the color adulteration by the aid of a simple photobleaching pretreatment using a 365 nm ultraviolet-light-emitting diode working at a photon flux density of 480 mmol m-2 s-1 for 24 min. The content of copper chlorophyll [predominantly Cu-pyropheophytin a (Cu-py a)] can be calculated by A600, A650, and A700 with satisfactory spike recovery [97.9-103.6%; six kinds of edible oils spiked with 1 ppm of Cu-py a; n = 3 for each kind of oil; relative standard deviation (RSD) < 5%], linearity ( R2 = 0.9961 when spiking 0.1-10 ppm of Cu-py a into soybean oil standard; n = 3 for each concentration; RSD < 5%), and reproducibility (RSD < 5% for spiking 1 ppm of Cu-py a into soybean oil standard; n = 3 over 3 days). The detection limit (S/N > 5) was 0.05 ppm. The analytical results of 50 commercially available oil samples were verified by the official high-performance liquid chromatography method.

Genetic dissection reveals that Akt is the critical kinase downstream of LRRK2 to phosphorylate and inhibit FOXO1, and promotes neuron survival.

Leucine-rich repeat kinase 2 (LRRK2) is a complex kinase and mutations in LRRK2 are perhaps the most common genetic cause of Parkinson's disease (PD). However, the identification of the normal physiological function of LRRK2 remains elusive. Here, we show that LRRK2 protects neurons against apoptosis induced by the Drosophila genes grim, hid and reaper. Genetic dissection reveals that Akt is the critical downstream kinase of LRRK2 that phosphorylates and inhibits FOXO1, and thereby promotes survival. Like human LRRK2, Drosophila lrrk also promotes neuron survival; lrrk loss-of-function mutant displays reduced cell numbers, which can be rescued by LRRK2 expression. Importantly, LRRK2 G2019S and LRRK2 R1441C mutants impair the ability of LRRK2 to activate Akt, and fail to prevent apoptotic death. Ectopic expression of a constitutive active form of Akt hence is sufficient to rescue this functional deficit. These data establish that LRRK2 can protect neurons from apoptotic insult through a survival pathway in which LRRK2 signals to activate Akt, and then inhibits FOXO1. These results might indicate that a LRRK-Akt therapeutic pathway to promote neuron survival and to prevent neurodegeneration in Parkinson's disease.

Clinicopathologic analysis of rhabdoid meningioma.

Rhabdoid meningioma is an uncommon variant of meningioma, and was classified separately for the first time in the 2000 World Health Organization's classification of tumors of the nervous system. Because it often shows malignant histological features and follows an aggressive clinical course, it has been classified as a grade III neoplasm. We describe the clinicopathologic features of 13 patients with this rare tumor. From 13 patients (seven male, six female), 19 specimens of rhabdoid meningioma were obtained between 2001 and 2009. The mean age of patients was 50.4years at their first operation. The mean postoperative follow-up period was 35.7months. Five patients experienced tumor recurrence, and two patients died from the disease. The mean time to first recurrence was 36.1months. The recurrence-free survival rates at 1 and 5years were 62% and 23%, respectively. Immunohistochemically, all tumors were positive for vimentin and epithelial membrane antigen. MIB-1 labeling indices were higher following tumor recurrence. Close follow-up and aggressive treatment of these tumors is warranted.

Nocardial brain abscess.

Nocardial infections, although rare, are challenging for clinicians to treat. The associated mortality rate remains high; such infections usually occur in immunocompromised patients who have predisposing factors such as malignancy, diabetes mellitus, malnutrition and uremia. However, there have been increasing reports of nocardial infections being observed in immunocompetent patients. Nocardial organisms are mostly isolated from plants and soil, and infection occurs most often as a result of inhalation or direct skin inoculation. Nocardial infections disseminate hematogenously from the primary location to distant end organs, including the brain, kidneys, joints and eyes. Sulfonamides are the drug of choice, based on empirical data. Given the high rate of relapse and the characteristic resistance pattern, treatment should be aggressive and continued for months, with antibiotic treatment being adjusted according to the drug sensitivity test. In our institution, there have been three documented patients with a nocardial brain abscess. All patients were treated with surgical evacuation followed by antibiotics. Here, we report on one patient and review the literature.

Breast carcinoma metastasis to intracranial meningioma.

Meningiomas and breast cancers are common tumors among women in the fifth to seventh decade. However, metastasis from breast cancer to an intracranial meningioma is rare. A 63-year-old woman presented with headache, nausea and vomiting, and progressive right hemiparesis for one month. She had undergone a right modified radical mastectomy in another hospital 10 years prior. At that time, the pathological diagnosis was infiltrating ductal carcinoma. She required adjuvant radiotherapy and chemotherapy for a local recurrence 7 years later. On admission to our hospital, cranial CT scans showed a brightly enhancing, irregularly shaped lesion over the left high parietal lobe with surrounding parenchymal edema. Histopathological examination of the lesion revealed two distinct tumor types, meningioma and metastatic carcinoma of breast tissue origin. Although meningiomas have well-known radiological features, other tumors, including metastases from breast cancers may simulate them. In the clinical setting of previously diagnosed breast cancer, prompt craniotomy for removal of meningioma-like intracranial lesions is recommended to avoid missing the diagnosis of breast cancer metastasis which carries a poorer prognosis than meningioma and requires a different treatment strategy.