MSH2 c.1452-1455delAATG Is a Founder Mutation and an Important Cause of Hereditary Nonpolyposis Colorectal Cancer in the Southern Chinese Population

Hereditary nonpolyposis colorectal cancer (HNPCC) accounts for ∼2% of all colorectal cancer (CRC) cases and is the most common hereditary CRC syndrome. We have previously reported a high incidence of microsatellite instability (MSI) and germline mismatch repair (MMR) gene mutations in young Hong Kong Chinese with CRC. Ongoing studies at the Hereditary Gastrointestinal Cancer Registry in Hong Kong have revealed a unique germline MSH2 c.1452-1455delAATG mutation that has not been reported in other ethnic groups. Detailed analysis showed that this specific MSH2 mutation constituted 21% of all germline MMR gene mutations and 36% of all MSH2 germline mutations identified. We designed a specific PCR-based diagnostic test on paraffin-embedded tissues and identified this germline mutation in 2 1.5%) of 138 consecutive patients with early-onset CRC (93 million. Further analysis suggested that this founder mutation may date back to between 22 and 103 generations ago. The identification of this MSH2 founder mutation has important implications for the design of mutation-detection strategies for the southern Chinese population. Since there were major emigrations from Hong Kong and Guangdong province during the 19th and 20th centuries, this finding is also significant for Chinese communities worldwide.published_or_final_versio

Ultra-diffuse hydrothermal venting supports Fe-oxidizing bacteria and massive umber deposition at 5000 m off Hawaii

© International Society for Microbial Ecology, 2011. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in The ISME Journal 5 (2011): 1748–1758, doi:10.1038/ismej.2011.48.A novel hydrothermal field has been discovered at the base of Lōihi Seamount, Hawaii, at 5000 mbsl. Geochemical analyses demonstrate that ‘FeMO Deep’, while only 0.2 °C above ambient seawater temperature, derives from a distal, ultra-diffuse hydrothermal source. FeMO Deep is expressed as regional seafloor seepage of gelatinous iron- and silica-rich deposits, pooling between and over basalt pillows, in places over a meter thick. The system is capped by mm to cm thick hydrothermally derived iron-oxyhydroxide- and manganese-oxide-layered crusts. We use molecular analyses (16S rDNA-based) of extant communities combined with fluorescent in situ hybridizations to demonstrate that FeMO Deep deposits contain living iron-oxidizing Zetaproteobacteria related to the recently isolated strain Mariprofundus ferroxydans. Bioenergetic calculations, based on in-situ electrochemical measurements and cell counts, indicate that reactions between iron and oxygen are important in supporting chemosynthesis in the mats, which we infer forms a trophic base of the mat ecosystem. We suggest that the biogenic FeMO Deep hydrothermal deposit represents a modern analog for one class of geological iron deposits known as ‘umbers’ (for example, Troodos ophilolites, Cyprus) because of striking similarities in size, setting and internal structures.Funding has been provided by the NSF Microbial Observatories Program (KJE, DE, BT, HS and CM), by the Gordon and Betty Moore Foundation (KJE), the College of Letters, Arts, and Sciences at the University of Southern California (KJE) and by the NASA Astrobiology Institute (KJE, DE)

The evolution of private provision in urban drinking water: New geographies, institutional ambiguity and the need for political economy

Empirical research paints a dynamic picture of the evolution of private provision in urban drinking water. A second wave of privatisation is clustered in a key group of countries, distinguished by the rise of new domestic private and quasi-private providers. This is, however, taking place in the presence of a counter-dynamic of remunicipalisation. In response to the complexity in provision arrangements revealed, three case studies are used to illustrate how different power balance configurations in the state-society-capital complex inform particular institutional arrangements. In Germany, civil society pressure challenged private capital resulting in the reinstatement of municipal control in Berlin, but at high long-term costs. In Russia, disempowered civil society has watched as the ruling regime exploits the support of international public agencies and foreign investors, while carefully safeguarding the interests of domestic private capital. In China, different levels of the state have promoted quasi-state actors into global corporations, managing the entry of international capital in order to bolster domestic support for desired political reforms. Public responsibility, and equally the re-assertion of public control after a period of private provision, may not in itself secure net social benefit where the right of capital to profit is put before broader social considerations

Cutaneous epithelioid angiosarcoma: A potential diagnostic trap for cytopathologists

We report on the cytologic features of a rare case of cutaneous epithelioid angiosarcoma of the scalp occurring in a 65-yr-old Chinese male. The prominent epithelioid features may cytologically mimic poorly- differentiated carcinoma, malignant melanoma, and even epithelioid sarcoma. Recognition of subtle cytologic features of vasoproliferation, immunohistochemical demonstration of endothelial markers, and ultrastructural examination are necessary before a final conclusion may be drawn.link_to_subscribed_fulltex

Dysembryoplastic neuroepithelial tumor: A tumor with small neuronal cells resembling oligodendroglioma

Dysembryoplastic neuroepithelial tumor (DNT) is a clinicopathologically unique group of tumors, mostly located in the temporal lobe, associated with intractable complex partial seizure in young patients. We report two unusual cases with multifocal involvement of diverse sites in the central nervous system. Case 1 is that of a 50-year-old man with 9-year history of grand mal seizures, who died of acute myocardial infarction. Case 2 is that of a 10- year-old girl with intractable complex partial seizures and behavioral disorder. Postmortem examination in case 1 showed multifocal tumor in the left temporal lobe, third ventricle, and basal ganglia. Magnetic resonance imaging in case 2 showed tumor in the right temporal lobe, both thalami, right cerebellar hemisphere, and pons. Histologically, both tumors were characterized by a multinodular appearance with a predominant component of alveolar arrangement of oligodendroglial-like cells around delicate capillaries, with mucoid matrix containing floating ganglion cells. There were also astrocytic nodules resembling pilocytic astrocytoma in case 1, and a gangliocytoma-like area merging with surrounding cortical dysplasia in case 2. Ultrastructural examination showed ganglionic differentiation in the oligodendroglial-like cells in case 2. They possessed dense core neurosecretory granules and many slender neuritic processes with microtubules arranged in parallel and terminating in synaptic junctions. The periventricularly located tumor with nodular extension to the periphery suggests an origin from subependymal germinal matrix with nests of primitive neuroblasts arrested in their embryonal migration. DNTs are related to ganglioglioma based on their common location and clinical behavior and on the presence of both ganglionic and astrocytic cells. They are also related to pilocytic astrocytoma by morphological and behavioral similarity. Together with cerebral neuroblastoma and central neurocytoma, they form a spectrum of tumors harboring small neuronal cells. The differentiation of DNT from oligodendroglioma is important so as to avoid unnecessarily aggressive therapy.link_to_subscribed_fulltex

Clinicopathologic study of 16 cases of primary tubal malignancy

Sixteen cases of primary carcinoma of the fallopian tube were diagnosed and treated at Queen Mary Hospital, Hong Kong from July 1972 to June 1992 constituting 0.26% of the total gynecologic malignancies seen during that period. The average age was 61 years and the most common presenting symptom was abnormal vaginal bleeding. Preoperative diagnosis is difficult; in only one case was a diagnosis of malignancy made by cervical smear. An adnexal mass was detected in 13 of the cases (81.3%) either by clinical examination and/or ultrasonography. Therapy consisted of surgical resection, usually followed by various combinations of adjuvant radiation therapy and chemotherapy. The cumulative survival was 62%. In addition to the typical form of adenocarcinoma, one case of squamous cell carcinoma and a case of multifocal endometrioid adenocarcinoma were observed. One case of an apparently usual form of adenocarcinoma recurred as a heterologous malignant mixed Mullerian tumor 2 years after diagnosis. This series further emphasises the wide range of differentiation possible in the Mullerian system and the variety of neoplasms which may arise from it.link_to_subscribed_fulltex