North American Journal of Medicine and Science
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Revisiting the Natural History of Chronic Hepatitis B in Asian Americans
Get PDFWorldwide, there are estimated to be 400 million people chronically infected with hepatitis B virus (HBV). In Asia, perinatal transmission of HBV from mother to newborn accounts for the high incidence of CHB infection Perinatally acquired CHB patients have unique features in their natural history, characterized by a long duration of immunotolerance phase, unpredictable patterns of disease reactivation and inactivation, and high risk for cirrhosis or HCC. Asian Americans, 60% of whom are foreign born, thus have similar patterns in the natural history of their disease. This article is a systemic review on the natural history of CHB in the Asian and Asian American population. Future research directions in this special population will also be explored
Sino-American Medical Exchange
Get PDFThe purpose of this article is to offer a template for developing Sino-American medical exchange programs. As globalization is the trend among professions and enterprises, exchange programs in medical education emerge as an ideal vehicle to promote and foster Sino-American relationships and improve world health. Brown University’s Alpert Medical School (AMS) and the Program in Liberal Medical Education (PLME) offers examples of two program templates for developing ongoing Chinese exchange programs. The author believes that three key components are essential for developing and sustaining ongoing exchanges: an interested and devoted faculty member from both countries of the exchange; the support of the highest level of administration at each institution as an exchange involves the waiver of tuition as well as administrative staff necessary to administer the exchange; and funding options to assist in travel, housing and board. Other models of exchange programs will briefly be reviewed as alternative options
Primary Carcinosarcoma of Bone: A Case Report with Review of the Literature
Get PDFPrimary carcinosarcoma of the bone is an extremely rare entity with only a few other cases reported in the literature. Here we describe such a neoplasm in a 63-year-old Caucasian male who presented with back pain and a pathologic fracture of T10 with lesions at T11, T12, and L1. A CT scan was done which showed a lytic lesion in the right posterior body of T11 measuring 2.2 cm. The patient had an open biopsy of this lesion that revealed a poorly differentiated spindle cell neoplasm. Microscopically, the lesion consists of a malignant spindle cell proliferation with marked nuclear pleomorphism, nuclear hyperchromasia, and an increased N/C ratio with some multinucleated forms present. Mitotic figures and atypical mitotic figures are also noted. Immunohistochemical analysis shows that the tumor cells are positive for Vimentin, CAM 5.2, and focally positive for low-molecular weight cytokeratin and high molecular weight cytokeratin. The tumor cells are negative for S100, HMB45, melan A, SMA, muscle specific actin, desmin, pancytokeratin, EMA, CD31, CD34, CD30, Alk-1, TTF-1, calretinin, BerEP4, and thyroglobulin. The tumor cells are also negative for mucicarmine and alician blue pH 2.5. The morphology along with the immunohistochemical profile of the tumor is diagnostic for carcinosarcoma. Further workup revealed lesions in his right hip and left rib, but no other non-osteologic source for a primary lesion. The patient’s past medical history includes a resection of a scapular tumor 15 years ago that was diagnosed as low-grade chondosarcoma. These slides were reviewed and appear unrelated to the current diagnosis. The patient is currently undergoing chemotherapy with no new disease after 10 months. A literature review showed cases with similar morphologic and immunohistochemical features to this case
Looking for Biomarkers for Prostate Cancer Early Detection
Get PDFCancer is a diverse disease and each cancer has different mechanism. To find a highly sensitive and specific biomarker that can reflect a single cancer, is a challenge for detection or therapeutic purpose. Gene expression profiling, proteomics, and immunology are used with increasing frequency as tools for cancer screening. The prostate-specific antigen (PSA) test is widely used as a screening test in prostate cancer. However, low specificity of serum PSA leads to many false-negative and false-positive results. We note that maintaining high specificity (low false-positive rates) is a very high priority for population screening. A small false-positive rate can translate into a large number of people who will suffer unnecessary costly further diagnosis and psychological stress. So, it is necessary that a biomarker of prostate cancer be both sensitive and specific.1 Beyond prognosis for prostate cancer, it is also very important to find molecular biomarkers correlating to prostate cancer disease progression. True et al. reported a molecular signature of 86 genes correlating to the Gleason grading system for prostate adenocarcinoma.2 Laxman showed a multiplex biomarker analysis of urine, which included six genes for prostate cancer detection.3 Recently, Chinnaiyan’s lab demonstrated a robust pipeline for the discovery of novel gene chimaeras by high-throughput sequencing.4 Metabolic profiling has shown a potential role for sarcosine in prostate cancer progression by using a combination of high-throughput liquid-and-gas-chromatography-based mass spectrometry in Chinnaiyan’s group.
The Expression of TTF-1 in Small Cell Carcinoma of Urinary Bladder
Get PDFSmall cell carcinoma (SMCC) of the urinary bladder is a rare tumor, accounting for less than 1% of all malignant neoplasms in the urinary bladder. Recently, thyroid transcription factor-1 (TTF-1), a putative marker for tumors originating from the lung and thyroid, was found to be expressed in SMCCof the urinary bladder, albeit in only a very small number of cases. Herein we report two additional cases of SMCCof the urinary bladder expressing TTF-1. The first patient was a 68-year-old white male with a 5-year history of a small focus of prostatic adenocarcinoma (biopsy proven) who was being treated with brachytherapy. He subsequently developed multiple large nodules at the base of the bladder, which by biopsy identified the presence of loosely cohesive small cells with minimal cytoplasm, coarsely and finely granular chromatin and indistinct nucleoli. Tumor cells were positive for TTF-1, CD56, chromogranin, synaptophysin and Cam 5.2, and negative for PSA. The location, morphological and immunochemical features of the tumor were diagnostic for SMCCof the urinary bladder. The second patient was a 76-year-old white female with a history of recurrent episodes of urinary tract infections. A biopsy showed a poorly differentiated carcinoma. The subsequent cystectomy revealed the presence of a 4.5 x 4.5 x 2.1 cm. tumor composed of a mixture of infiltrating high grade urothelial carcinoma and small cell carcinoma. The small cell component possessed similar morphological and immunohistochemical features as previously described in the first case, including positive expression for TTF-1. These two cases illustrate and concur with previous assertions that TTF-1 cannot be used to distinguish primary SMCC of the urinary bladder from metastatic SMCC of lung.
A Giant Atypical Neurofibroma in the Right Thoracic Cavity of a 57-Year-Old Man: A Case Report with Review of the Literature
Get PDFIntrathoracic neurogenic tumors are not uncommon, but presentation as a giant mass in the thoracic cavity is rare. Although several cases of intrathoracic giant malignant peripheral nerve sheath tumor have been reported, only one case of intrathoracic giant benign neurofibroma appears in the literature. In this report, we describe a very rare case of atypical giant neurofibroma in the right thoracic cavity. The patient was a 57 year old African American man, who developed sudden cardiac arrest and passed away in the emergency room. At autopsy, a huge encapsulated firm tumor was found in the right thoracic cavity, attached to the vertebral bodies and superficially adherent to the upper and middle lobes of the right lung. This giant mass weighed 2140 grams and measured 31 x 30 x 5.5 cm. Microscopically, the tumor consisted of interweaving fascicles of spindle cells with scattered atypical nuclei. Immunohistochemical studies showed that tumor cells were focally positive for S100, and negative for SMA, desmin, calretinin, Pan CK, CK5/6, EMA, CD99, CD34 and p53. The overall morphological and immunohistochemical features were diagnostic of an atypical neurofibroma.
Optic Nervev Neuropathy and repair in Gloucoma
Get PDFGlaucoma is one of the leading causes of impaired vision and blindness worldwide. It is a disease involving progressive optic nerve pathology and retinal ganglion cell (RGC) function loss.1 Optic neuropathy and RGC death are the hallmarks of glaucoma, which are often associated with structural changes in the optic nerve head.2,3 Effective therapeutic strategies to treat neuronal damage and restore vision in glaucoma rely heavily on the knowledge and understanding of the cellular and molecular responses in RGCs and the optic nerve
Rationale and Problems for Use of Coptis and Berberine in Cancer Chemoprevention
Get PDFCoptis (Huang Lian) is a very popular therapeutic herb in China. The pharmacological name of coptis is rhizoma coptidis and the botanical name is coptis chinesis franch. Coptis grows in many areas around the globe. There are about 15 major species of coptis in China, including C. chinesis, C. deltoidea, C. orneiensis, C. teetoides and C. quinquesecta. Coptis chinensis, or duan e huang lian in Chinese, has been widely used in traditional Chinese medicine. Coptis aspleniifolia (spleenwort-leaf goldthread) and coptis occidentalis (Idaho Goldthread) are popular herbs native to North America
Research Update on Iron Metabolism and Its Regulation Mechanisms
Get PDFIron metabolism disorder is an important public health problem both in the United States and developing world. Iron deficiency cases are over 2 billion worldwide. In theU.S., 9 million people are iron deficient and 1 million are at genetic risk of iron overload. Recent advances in research on iron-related diseases, coupled with new insights into the molecular mechanisms for iron metabolism, have strengthened our understanding of iron metabolism and iron disorder and have the potential to improve clinical and laboratory assessments of patients. In this article, I aim to provide a brief summary of recent developments in the molecular mechanisms underlying iron metabolism
Trans Fat and Cardiovascular Disease
Get PDFCardiovascular disease remains the number one killer in the United States. According to the American Heart Association statistics, CVD accounted for 35.2% of total deaths in 2005 in the United States.1 This is also true for developing countries, such as China and India: CVD has also become the first or second leading causes of death; it is responsible for around 30% of total deaths in developing countries.2 Of many risk factors for CVD, dietary intake of fats received much attention and has been extensively studied due to the facts that blood cholesterol levels are a strong predictor for CVD3 and that dietary fats are a strong determinant for serum lipids.4 Although the effects of some fatty acids on coronary health are still a matter of debate, the relationship between trans fatty acids and risk of CVD has been established.