Detection and diagnosis of blood in feces and urine: an overview

BACKGROUND: Detection of blood in feces or urine has long been regarded as an indicator of patient's state of health. The ease with which feces or urine may be obtained and patient's willingness to provide the specimen make detection of fecal occult blood or urine analysis one of the most commonly performed screening examinations. Historically, the inspection of feces or urine for diagnostic purpose has been practiced for centuries. Of late, management of renal or urinary tract abnormalities or investigation of anemia, gastrointestinal diseases and for early detection of colorectal cancer has assumed greater importance. METHODS: The never-ending list of techniques for the diagnosis of disorders producing bleeding such as urine microscopy, urine cytology, urine based marker test, cytoscopy, ultra sonography, computed tomography, magnetic resonance imaging, to mention a few, and four categories of detection of fecal occult blood namely, radioanalytical, physical, immunochemical and chemical methods makes the study very interesting. PURPOSE: This review attempts to overview various techniques, methods and methodologies for the diagnosis and detection of blood in feces and urine, in the direction of looking at past and current tests with an eye on future needs.     

Biochemical studies on the toxicity of hematite dust

Biochemical alterations in guinea pig lungs caused by hematite dust were followed at 150 days after intratracheal administration of the dust. In vivo dust exposure caused a significant increase in mitochondrial protein content and cytochrome c oxidase activity whereas diaphorase activity remained unaltered. Mitochondria from the exposed animals were apparently in a swollen state and their contraction profile upon the addition of ATP reflected permeability changes. However, in vitro dust caused no significant alterations. Significant increases in glycogen content along with an insignificant decrease in glycogen phosphorylase activity were also observed in hematite-treated guinea pig lungs. Decrease in drug-metabolizing enzymes such as aniline hydroxylase and tyrosine aminotransferase activities were also evident in the postmitochondrial fraction of the siderotic lungs. [3H]Leucine-incorporation studies showed increased protein synthesis in the postmitochondrial fraction. Increase in protein synthesis in mitochondria was only marginal whereas in whole homogenate it decreased considerably. Experiments employing dust tagged with radioactive iron indicated the rapid mobilization of iron from lung and its distribution to various organs. The presence of iron-binding protein was confirmed by employing Sephadex gel-filtration techniques.     

Physicochemical and immunological studies on 4-hydroxynonenal modified HSA: Implications of protein damage by lipid peroxidation products in the etiopathogenesis of SLE

4-Hydroxynonenal (HNE) is the most abundant and toxic aldehyde generated by the oxidation of plasma membrane polyunsaturated fatty acids. Systemic lupus erythematosus (SLE), a chronic autoimmune disease, is primarily characterized by increased levels of autoantibodies, predominantly against ds-DNA. However, the initial antigenic stimulus for the disease etiopathogenesis has remained elusive. HNE has been extensively used as a biomarker of oxidative stress. It can form adduct with proteins, making them highly immunogenic. Increased levels of such aldehyde–protein adducts have been reported in various pathological states, including autoimmune disorders like SLE and arthritis. In the present study, HNE-mediated structural changes in human serum albumin (HSA) were characterized by UV, fluorescence, CD and FT-IR spectroscopy as well as by polyacrylamide gel electrophoresis. Furthermore, immunogenicity of native and HNE-modified HSA was probed in female rabbits. The HNE-modified HSA was highly immunogenic eliciting high titre immunogen specific antibodies. Binding of SLE anti-DNA antibodies was analyzed by direct binding and competition ELISA. The data show preferential binding of SLE autoantibodies to HNE-modified HSA as compared to native HSA or native DNA. Our results suggest that HNE modification generates neoepitopes on HSA causing enhanced autoantibodies production. The results point towards the possible role of HNE-modified HSA in SLE etiopathogenesis.     

Significance and mechanism of Alzheimer neurofibrillary degeneration and therapeutic targets to inhibit this lesion

Abnormally hyperphosphorylated tau which is the major protein subunit of paired helical filaments (PHF)/neurofibrillary tangles is the pivotal lesion in Alzheimer disease (AD) and related tauopathies. The cosegregation of tau mutations with disease in inherited cases of frontotemporal dementia has confirmed that abnormalities in this protein can be a primary cause of neurodegeneration. Unlike normal tau that promotes assembly and maintains the structure of microtubules, the abnormally hyperphosphorylated protein sequesters normal tau, MAP1 and MAP2 and consequently disassembles microtubules. The abnormal hyperphosphorylation also promotes the self assembly of tau into tangles of PHF. The hyperphosphorylation of tau in AD is probably due to a protein phosphorylation/dephosphorylation imbalance produced by a decrease in the activity of protein phosphatase (PP)-2A and increase in the activities of tau kinases which are directly or indirectly regulated by PP-2A. Two of the most promising pharmacologic therapeutic approaches to AD are (1) the development of drugs that can inhibit the sequestration of normal MAPs by the abnormally hyperphosphorylated tau, and (2) the development of drugs that can reverse the abnormal hyperphosphorylation of tau by correcting the protein phosphorylation/dephosphorylation imbalance.     

Rosiglitazone protects the dorsal root ganglion cells and sciatic nerve after crush in rat

The aim of this study was to investigate the histological changes in the dorsal root ganglion (DRG) and the sciatic nerve in rats after sciatic nerve crush (SNC) and treatment with rosiglitazone. The rats were divided into four groups, each including seven animals, and underwent the following intervention. Group I: control animals which received carboxy methyl cellulose (0.5 w/v, p.o.). Group II: sham operated animals whose skin of the posterior thigh was opened, closed and the animals received the vehicle (carboxy methyl cellulose). Group III: SNC animals; the animals received the vehicle. Group IV: SNC with rosiglitazone (5 mg/kg body weight/day) dissolved in the vehicle. On the 28th day the fifth lumbar DRG and sciatic nerve were removed. Volume of the dorsal root ganglion, total volume and number of cells (A and B cells) of DRG, total surface area of the cells, and total number, diameter and cross-sectional area of the myelinated nerve fibres were estimated using stereological techniques. No change was observed in volume of the DRG, but all of the other parameters were decreased after nerve crush. In SNC+ rosiglitazone treated rats, the parameters decreased but to a lesser extent in comparison with the non-treated SNC group. It can be concluded that rosiglitazone has a protective effect on the DRG cells and sciatic nerve after crush in rats.     

Toward gene therapy of primary ovarian failure: adenovirus expressing human FSH receptor corrects the Finnish C566T mutation

Resistance ovarian syndrome is a heterogeneous disorder inherited as a Mendelian recessive trait and characterized by infertility, primary amenorrhea, normal karyotype and elevated serum FSH and LH levels. An inactivating mutation, C566T, in FSH receptor gene (FSHR) has been identified initially in Finland. We investigated if an adenovirus expressing a normal copy of human FSHR (Ad-hFSHR) has the ability to: (i) transfect granulosa cell lines, (ii) render the transfected cell lines responsive to FSH stimulation and (iii) transcomplement the malfunctioning form of human FSHR gene with C566T mutation. COS-7, JC-410, JC-410-P450-scc-luc and JC-410-StAR-luc cell lines were infected by Ad-hFSHR followed by treatment with FSH. Functional activity of the Ad-hFSHR was tested by measuring cyclic adenosine monophosphate (cAMP) or luciferase activity in response to FSH stimulation, and showed 2-4.6-fold increases in Ad-hFSHR transfected cells compared with untransfected or Ad-LacZ transfected cells, indicating that Ad-hFSHR is functionally active and expressing hFSHR. Generation of cAMP in cells expressing only mutated hFSHR-T566 showed minimal increase after FSH stimulation. Co-transfection of Ad-hFSHR in these cells carrying the malfunction form of human FSHR caused significant increases of 2.2-7.4-fold in FSH dependent cAMP generation (P = 0.0007). We concluded that adenovirus expressing a normal human FSHR can compensate the inactivating human FSHR-C566T mutation and restore FSH responsiveness.     

Prevalence of occult metastases in axillary sentinel lymph nodes of breast carcinoma

Recently, sentinel lymph node biopsy (SLNB) has been accepted as a standard method of assessment of axillary lymph nodes in breast cancer patients with no clinical lymphadenopathy. There is no standard pathologic method to evaluate sentinel lymph nodes. The purpose of this study is to evaluate the frequency of occult lymph node metastasis in sentinel lymph nodes via serial sectioning and immunohistochemical study with cytokeratin and its relationship with other clinicopathologic factors. Paraffin-embedded blocks of axillary sentinel lymph nodes of breast cancer patients, biopsied in 2005-2009 and reported as negative, were reviewed with 3 μm sections, H and E staining and immunohistochemical study with an epithelial cytokeratin marker. Clinicopathologic data and relapse, if occurred was recorded and its relationship with occult metastasis was statistically analyzed. Sixty-eight sentinel pathology blocks of 66 patients (65 women and one man, median age 49 years) were investigated. Four cases (5.8%) of occult metastases were found, one by HE staining, and three cases with IHC (1 micrometastasis, 2 isolated tumor cells). Accuracy of reported cases was 94.1% upon re-examination. Sixty-four patients were followed after surgery and adjuvant therapy (range: 6-38 months, median: 21 months). No relapse was reported. There was no significant statistical relationship between occult metastasis and disease-free survival. Although 4 cases (5.8%) of sentinel lymph nodes were positive in the complementary study, with a median follow-up of 21 months, we found no difference in disease-free survival between these patients and others. To show a significant, however small, difference, one needs further research with a greater number of patients and longer follow-up.     

Achieving Millennium Development Goals 4 and 5 in Bangladesh

Bangladesh has made commendable progress in achieving Millennium Development Goals (MDGs) 4 and 5. Since 1990, there has been a remarkable reduction in maternal and child mortality, with an estimated 57% reduction in child mortality and 66% in maternal mortality. This review highlights that, whereas Bangladesh is on track for achieving MDG 4 and 5A, progress in universal access to reproductive health (5B) is not yet at the required pace to achieve the targets set for 2015. In addition, Bangladesh needs to further enhance activities to improve newborn health and promote skilled attendance at birth.