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2.
Am J Gastroenterol ; 110(2): 328-35, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25512338

ABSTRACT

OBJECTIVES: Anticoagulants carry a significant risk of gastrointestinal bleeding (GIB). Data regarding the safety of anticoagulation continuation/cessation after GIB are limited. We sought to determine the safety and risk of continuation of anticoagulation after GIB. METHODS: We conducted a prospective observational cohort study on consecutive patients admitted to the hospital who had GIB while on systemic anticoagulation. Patients were classified into two groups at hospital discharge after GIB: those who resumed anticoagulation and those who had anticoagulation discontinued. Patients in both groups were contacted by phone 90 days after discharge to determine the following outcomes: (i) thromboembolic events, (ii) hospital readmissions related to GIB, and (iii) mortality. Univariate and multivariate Cox proportional hazards were used to determine factors associated with thrombotic events, rebleeding, and death. RESULTS: We identified 197 patients who developed GIB while on systemic anticoagulation (n=145, 74% on warfarin). Following index GIB, anticoagulation was discontinued in 76 patients (39%) at discharge. In-hospital transfusion requirements, need for intensive care unit care, and etiology of GIB were similar between the two groups. During the follow-up period, 7 (4%) patients suffered a thrombotic event and 27 (14%) patients were readmitted for GIB. Anticoagulation continuation was independently associated on multivariate regression with a lower risk of major thrombotic episodes within 90 days (hazard ratio (HR)=0.121, 95% confidence interval (CI)=0.006-0.812, P=0.03). Patients with any malignancy at time of GIB had an increased risk of thromboembolism in follow-up (HR=6.1, 95% CI=1.18-28.3, P=0.03). Anticoagulation continuation at discharge was not significantly associated with an increased risk of recurrent GIB at 90 days (HR=2.17, 95% CI=0.861-6.67, P=0.10) or death within 90 days (HR=0.632, 95% CI=0.216-1.89, P=0.40). CONCLUSIONS: Restarting anticoagulation at discharge after GIB was associated with fewer thromboembolic events without a significantly increased risk of recurrent GIB at 90 days. The benefits of continuing anticoagulation at discharge may outweigh the risks of recurrent GIB.


Subject(s)
Anticoagulants/adverse effects , Gastrointestinal Hemorrhage/chemically induced , Ischemic Attack, Transient/prevention & control , Pulmonary Embolism/prevention & control , Stroke/prevention & control , Venous Thrombosis/prevention & control , Withholding Treatment/statistics & numerical data , Aged , Aged, 80 and over , Anticoagulants/administration & dosage , Benzimidazoles/adverse effects , Cohort Studies , Dabigatran , Enoxaparin/adverse effects , Female , Gastrointestinal Hemorrhage/drug therapy , Heparin , Humans , Longitudinal Studies , Male , Middle Aged , Morpholines/adverse effects , Patient Readmission/statistics & numerical data , Prospective Studies , Pyrazoles/adverse effects , Pyridones/adverse effects , Recurrence , Rivaroxaban , Thiophenes/adverse effects , Thromboembolism/prevention & control , Warfarin/adverse effects , beta-Alanine/adverse effects , beta-Alanine/analogs & derivatives
3.
Aliment Pharmacol Ther ; 40(7): 804-10, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25109610

ABSTRACT

BACKGROUND: The treatment of HBeAg-negative chronic hepatitis B (CHB) is considered to be open-ended, with no guidelines for treatment cessation. AIM: To evaluate biochemical and virological relapse requiring retreatment in noncirrhotic HBeAg-negative CHB in patients who stopped treatment following a period of prolonged viral suppression with nucleotides/nucleosides. METHODS: We performed a single-centre retrospective chart review of patients with HBeAg-negative CHB who maintained viral suppression for 4-5 years on anti-viral treatment, and thus subsequently stopped treatment. The primary end point of composite relapse was defined by an increase in HBV DNA >2000 IU/mL, ALT elevation above 1.25 × normal or doubling of ALT from cessation, and re-initiation of anti-viral therapy. RESULTS: We identified 33 patients with HBeAg-negative CHB who stopped treatment following viral suppression. Mean treatment duration was 5.28 ± 2.73 years. Patients were treated with lamivudine (3), adefovir (14), entecavir (4), and tenofovir (12). Eleven (33%) patients met the primary end point of composite relapse. For individual end points, 21 (63%) patients had a viral relapse, 16 (48%) had a biochemical relapse, and 16 (48%) restarted treatment, leaving 17 (52%) patients who remained treatment-free over a median 36 months of follow-up. Lower pre-treatment ALT and detectable HBV DNA within the first month after treatment discontinuation were associated with increased rates of composite relapse (HR 1.01; P = 0.022 for ALT and HR 1.01; P = 0.038 for HBV DNA). CONCLUSION: Patients with noncirrhotic HBeAg-negative CHB can stop treatment after greater than 4-5 years of suppressive therapy with nucleosides/nucleotides with more than 50% remaining treatment-free.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis B, Chronic/drug therapy , Nucleosides/therapeutic use , Nucleotides/therapeutic use , Adenine/analogs & derivatives , Adenine/therapeutic use , Adult , Female , Guanine/analogs & derivatives , Guanine/therapeutic use , Hepatitis B e Antigens , Humans , Lamivudine/therapeutic use , Male , Middle Aged , Organophosphonates/therapeutic use , Recurrence , Tenofovir , Withholding Treatment , Young Adult
4.
Aliment Pharmacol Ther ; 40(4): 354-62, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24889902

ABSTRACT

BACKGROUND: Portal hypertensive gastropathy (PHG) and gastric antral vascular ectasia (GAVE) are important causes of both acute and chronic gastrointestinal bleeding in patients with cirrhosis. AIM: To review the current management of PHG and GAVE. METHODS: PubMed was searched for English language articles using the key words 'GAVE', 'gastric antral vascular ectasia', 'cirrhosis', 'gastrointestinal bleeding', 'acute', 'chronic', 'portal hypertensive gastropathy', 'watermelon stomach', 'radiofrequency ablation', 'band ligation', 'thermoablation' and 'TIPSS'. RESULTS: GAVE and PHG are both encountered in patients with cirrhosis. They can be seen in asymptomatic patients and in those with either acute or chronic gastrointestinal bleeding. PHG, by definition, requires the presence of portal hypertension, with or without cirrhosis, whereas GAVE requires neither cirrhosis nor portal hypertension. They can often be diagnosed on endoscopic appearance alone, but may require biopsy in certain cases. The treatment of PHG is aimed at reducing hepatic venous pressure gradients, most often by pharmacologic means, but may require shunt procedures in severe cases. Management of GAVE on the other hand is predominantly endoscopic, focusing on various ablative techniques. CONCLUSIONS: Gastric antral vascular ectasia and portal hypertensive gastropathy are distinct entities and are both encountered in cirrhotic patients. Management of portal hypertensive gastropathy is centred on reduction in portal pressures, whereas treatment of gastric antral vascular ectasia is predominantly endoscopic.


Subject(s)
Gastric Antral Vascular Ectasia/therapy , Hypertension, Portal/complications , Stomach Diseases/therapy , Biopsy , Endoscopy, Gastrointestinal/methods , Gastric Antral Vascular Ectasia/physiopathology , Gastrointestinal Hemorrhage/etiology , Humans , Hypertension, Portal/physiopathology , Liver Cirrhosis/complications , Portal Pressure , Stomach Diseases/etiology , Stomach Diseases/pathology , Venous Pressure
5.
J Viral Hepat ; 18(7): e366-71, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21692949

ABSTRACT

Chronic hepatitis C infection is associated with hypolipidaemia that resolves with viral clearance. Lipid levels in a subgroup of patients rebound to levels that may increase the risk of coronary heart disease. The impact of acute hepatitis C infection and its clearance on lipid levels is unknown. We undertook a retrospective evaluation of subjects with acute hepatitis C infection evaluating lipid levels before, during and following acute infection. Thirty-eight subjects with acute hepatitis C infection had lipid levels available. Twelve patients had pre-infection and intra-infection lipid levels available. Cholesterol (197.8-152.4 mg/dL, P = 0.025), low-density lipoprotein (LDL) (116.1-76.3 mg/dL, P = 0.001) and non-high-density lipoprotein (non-HDL) cholesterol (164.0-122.7 mg/dL, P = 0.007) decreased dramatically during acute hepatitis C virus infection. Nineteen patients who achieved viral clearance had lipid levels available during infection and following resolution of infection. In these patients, cholesterol (145.0-176.0 mg/dL, P = 0.01), LDL (87.0-110.1 P = 0.0046) and non-HDL cholesterol (108.6-133.6 mg/dL, P = 0.008) increased significantly. No change was seen in patients who developed chronic infection. Four patients had lipid levels before, during and following resolution of infections and had increased postinfection LDL, cholesterol and non-HDL cholesterol from pre-infection levels, indicating acute infection may be associated with an increase in postinfection lipid levels and may confer an increased risk of coronary heart disease. Acute hepatitis C infection results in hypolipidaemia with decreased LDL, cholesterol and non-HDL cholesterol levels that increase following infection resolution. Levels may increase above pre-infection baseline lipid levels and should be monitored.


Subject(s)
Hepatitis C/blood , Lipids/blood , Acute Disease , Adult , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Coronary Disease/blood , Female , Hepacivirus/genetics , Humans , Lipoproteins, HDL/blood , Lipoproteins, LDL/blood , Male , Middle Aged , RNA, Viral/blood , Risk Factors , Triglycerides/blood
6.
Cell Mol Life Sci ; 65(20): 3312-24, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18791851

ABSTRACT

Cardiac myocytes are the first cells to differentiate during the development of a vertebrate embryo. A wide variety of molecules take part in various steps in this process. While exploring biologically active molecules from marine sources, we found that a constituent of perivitelline fluid from embryos of the Indian horseshoe crab can enhance growth and differentiation of chick embryonic heart. We have purified the factor and identified the cardiac promoting molecule to be a novel lectin. We show that this molecule influences cardiac development by increasing the number of cells constituting the heart and by modulating the expression of several cardiac development regulatory genes in chick embryos. Using mouse embryonic stem cells we show that the cardiac myocyte-enhancing capacity of this molecule extends to mammals and its effects can be blocked using methylated sugars. This molecule may prove to be an important tool in the study of cardiomyocyte differentiation.


Subject(s)
Embryo, Nonmammalian/metabolism , Heart/embryology , Horseshoe Crabs/embryology , Lectins/pharmacology , Organogenesis/drug effects , Vertebrates/embryology , Vitelline Membrane/metabolism , Animals , Carrier Proteins/metabolism , Cell Count , Cell Differentiation/drug effects , Chemical Fractionation , Chickens , Embryonic Stem Cells/cytology , Embryonic Stem Cells/drug effects , Gastrulation/drug effects , Gene Expression Regulation, Developmental/drug effects , Heart/drug effects , Hematopoiesis/drug effects , Mice , Muscle Proteins/metabolism , Myocardium/cytology , Myocytes, Cardiac/cytology , Myocytes, Cardiac/drug effects , Neovascularization, Physiologic/drug effects , Organ Specificity/drug effects
7.
Curr Issues Mol Biol ; 6(2): 189-200, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15119827

ABSTRACT

Molecular phylogenetic trees are constructed in three dimensions relative to the distribution of MW and pl classes and immunocrossreactivity against polyclonal antibodies to lens crystallins, as well as multiple sequence alignment between amino acid sequences, coding nucleotide sequences and the gene nucleotide sequences for beta-globin. Euclidian distances are estimated to position species in x, y, z space by multidimensional scaling and merged with bootstrap-tested branching pattern of Fitch & Margoliash plots to obtain 3-D phylogenetic tree. Compared to single attributes, phylogenetic trees based on multiple parameters allow significant repositioning of rodents, chiroptera and primates.


Subject(s)
Phylogeny , Sequence Analysis, Protein/methods , Animals , Computer Simulation , Crystallins/genetics , Globins/genetics , Sequence Homology
8.
Dev Genes Evol ; 211(10): 478-85, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11702197

ABSTRACT

The anatomical and cell biological aspects of somite formation in the chick embryo have been rather well studied. Molecular regulation of somitogenesis in vertebrates is just beginning to be understood. We have studied the effects of human recombinant activin on somitogenesis in gastrulating chick embryos cultured in vitro with a view to assessing the possible role of activin-related molecules in this phenomenon. Activin disrupted somitogenesis in treated embryos, resulting in the formation of abnormal, split or ectopic somites. Light microscopic examination indicated that the ability of activin to interfere with somitogenesis might be partly due to initiation of somite formation at ectopic sites. We show that these cells are indeed somitogenic by their expression of one of the earliest somite-specific marker genes, Pax3. Scanning electron microscopic examination of control and treated embryos revealed direct effects of activin on cell-cell interactions. Cells from treated embryos exhibited disrupted intercellular adhesion leading to large intercellular spaces, altered cell shapes and modification of cell surface protrusions. The effects of activin on somitogenesis appear to be specific, since the neural structures, which are generally more susceptible to chemical insults during gastrulation, were relatively less affected. The results clearly point to a role of activin-related molecules in somitogenesis in the chick embryo.


Subject(s)
Activins/pharmacology , Chick Embryo/drug effects , Chick Embryo/embryology , Somites/drug effects , Transcription Factors , Animals , Chick Embryo/cytology , Chick Embryo/ultrastructure , Culture Techniques , DNA, Antisense/genetics , DNA-Binding Proteins/genetics , In Situ Hybridization , Microscopy, Electron, Scanning , PAX3 Transcription Factor , Paired Box Transcription Factors , RNA, Messenger/analysis , RNA, Messenger/genetics , Somites/cytology , Somites/metabolism , Somites/ultrastructure
9.
Neuroradiology ; 43(11): 961-7, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11760802

ABSTRACT

Although intramedullary spinal cord cysticercosis (IMC) is uncommon, its presence is being increasingly recognised by magnetic resonance imaging. We studied six patients from an endemic region and present the MRI features and clinical correlation of IMC. Six patients who presented with para- or quadriplegia were studied by contrast enhanced spinal MRI. Prompted by the spinal lesions, all patients underwent brain MRI. Clinical data and laboratory studies were reviewed in all patients. Definite diagnosis was established in the form of response to drug therapy (n = 4) and histopathology (n = 2). Follow-up MRI studies of spine and brain were obtained in four patients 2 months after they started medical treatment, regardless of surgery. Five patients showed fusiform and focal enlargement of the spinal cord (cervical 2, thoracic 3). Well-defined cysts with a slightly hyperintense mural nodule were identified in five patients in Ti-weighted images (T1WI). All cysts were hyperintense on T2WI and merged with the surrounding oedema. Oedema extended one to three vertebral levels above or below the cyst. Post-contrast T1WI showed well-defined, ring enhancing lesions with smooth walls in all patients. Symptoms in all patients correlated with the level of the lesions. Brain studies demonstrated lesions in just two patients. Histopathological confirmation was obtained in two patients. Follow-up spinal MRI was normal in two patients, following 2 months of treatment while residual and smaller lesions were seen in two patients. Two patients were asymptomatic and denied follow-up MRI. MRI of spinal cysticercosis were typical of and similar to those seen in cerebral lesions in our patients and corresponded to the level of symptoms. All cysts were surrounded by oedema. Two of four patients showed residual lesions after 2 months of therapy and 33 % of patients showed concomitant intracranial lesions.


Subject(s)
Cysticercosis/pathology , Spinal Cord Diseases/pathology , Spinal Cord Diseases/parasitology , Spinal Cord/pathology , Adult , Brain/pathology , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Middle Aged
11.
Dev Dyn ; 218(1): 123-35, 2000 May.
Article in English | MEDLINE | ID: mdl-10822265

ABSTRACT

During chick embryogenesis, cells destined to form cardiac myocytes are located within the primitive streak at stage 3 in the same relative anterior-posterior distribution as in the prelooped heart. The most rostral cells contribute to the extreme anterior pole of the heart, the bulbus cordis, and the most caudal to the extreme posterior end, the sinoatrial region. After gastrulation, these cells commit to the myocyte lineage and, retaining their relative positions, migrate to the anterior lateral plate. From stages 5 to 10 they diversify into atrial and ventricular myocytes, with the former located posteriorly and the latter, anteriorly. To determine the effect of a change in the rostro-caudal position of these cells on their diversification, anterior lateral plate mesoderm and the underlying endoderm were cut and rotated 180 degrees along the longitudinal axis, at stages 4-8. The subsequent diversification of these precursor cells into atrial and ventricular myocytes was examined using lineage-specific markers. Our results showed that altering location along the longitudinal axis through stage 6 changed the normal fate of a precursor cell. The orientation of the overlying ectoderm did not alter normal morphogenesis or determination of fate.


Subject(s)
Heart/embryology , Muscle Fibers, Skeletal/cytology , Myocardium/cytology , Animals , Carbocyanines , Cell Differentiation/physiology , Chick Embryo , Ectoderm/cytology , Fluorescent Dyes , Heart Atria/cytology , Heart Atria/embryology , Heart Ventricles/cytology , Heart Ventricles/embryology , Mesoderm/cytology , Rotation
12.
Cell Biol Int ; 20(8): 545-52, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8938988

ABSTRACT

The anticancer drug taxol brings about its biological effects by altering the stability of microtubules. We have examined the effects of taxol on early morphogenesis in chick embryos cultured in vitro. Taxol induced various abnormalities in the developing nervous system, heart and somites as well as general retardation of development. SEM studies revealed that taxol treatment leads to dramatic alterations in the embryonic cell surfaces. Time-course experiments demonstrated that the action of taxol is very rapid and becomes evident within a few minutes at the ultrastructural level. Taxol thus throws embryonic cell adhesion and motility out of balance. This appears to be the major cause of abnormal morphogenesis in taxol-treated embryos.


Subject(s)
Chick Embryo/drug effects , Microtubules/drug effects , Paclitaxel/toxicity , Animals , Cell Adhesion , Microscopy, Electron, Scanning , Microtubules/physiology , Morphogenesis/drug effects
13.
Indian J Biochem Biophys ; 32(1): 21-31, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7665191

ABSTRACT

Antisera prepared against total water-soluble lens proteins of the shark, Scoliodon sorrakowah were reacted with homologous antigen and analysed reaction products by immunoelectrophoresis (IE) and two dimensional crossed antigen-antibody electrophoresis (2D-CE). On IE, shark antigens formed 5 precipitin lines including 1 alpha, 3 beta and 1 gamma crystallins and on 2D-CE 3 alpha, 6 beta and 6 gamma peaks accounting for 8%, 27% and 65% antigen in the respective group were obtained from the total crystallins. Using anti-shark antisera, the immunocrossreactivity of lens proteins from 6 Chondropterygii, 23 teleosts and 16 higher vertebrates was examined by IE. It is found that beta crystallins are the most conserved and crossreact with all vertebrate classes, whereas gamma crystallin crossreactivity is specific to the class Pisces and alpha crystallins are least conserved and their crossreactivity is confined to subclass Chondropterygii. Based on IE patterns, a phylogenetic tree is constructed which demonstrates the intrafamily closeness except in case of adaptive radiation.


Subject(s)
Antigen-Antibody Reactions , Crystallins/immunology , Phylogeny , Sharks/immunology , Vertebrates/immunology , Animals , Cross Reactions
14.
J Indian Med Assoc ; 93(2): 58-9, 48, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7658039

ABSTRACT

PIP: The maternal mortality rate associated with eclampsia ranges from 100 to 6000 per 100,000, and the perinatal mortality rate ranges from 150 to 400 per 1000. Both eclampsia and its preceding condition, pregnancy-induced hypertension, occur in varying degrees in different parts of India. The warning signs of imminent eclampsia are 1) systolic blood pressure of 160 mmHg or more on two occasions six hours apart when the patient is on bed rest; 2) proteinuria of 5 g or more in 24 hours or 3 + or more by semiquantitative assay; 3) oliguria or anuria; 4) cerebral or visual disturbances; 5) pulmonary edema or cyanosis; and 6) epigastric/right hypochondriac pain, impaired liver function, and thrombocytopenia and coagulation disorders. Eclampsia is classified as the acute fulminating type, which can occur without warning, and the insidious type. Most cases (61%) show onset of eclampsia during the prenatal period. Treatment of eclampsia involves 1) control of convulsions (through an injection of magnesium sulphate or diazepam or the intravenous administration of phenytoin); 2) correction of hypoxia and acidosis; 3) a gradual lowering of blood pressure with hydralazine hydrochloride, nifedipine, atenolol, labetalol, oxprenolol, or metoprolol); and 4) steps to effect delivery. Diagnosis of HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets) requires a complete blood count, blood film for platelet count and red blood cell fragmentation, and a coagulation screen for diagnosis of disseminated intravascular coagulation. Efforts to induce delivery in cases of prenatal eclampsia can take place 12-24 hours after convulsions have stopped. There is no reason to prolong pregnancy in the interests of the fetus, and in some cases Cesarean section may be required. Adequate prenatal care should allow the identification of almost every potential case of eclampsia and allow the prompt treatment of pre-eclampsia or termination of pregnancy when necessary. Medical staff must receive proper training to diagnose pre-eclampsia and treat the condition.^ieng


Subject(s)
Eclampsia , Eclampsia/mortality , Eclampsia/therapy , Female , Humans , India/epidemiology , Maternal Mortality , Pre-Eclampsia , Pregnancy
15.
J Postgrad Med ; 40(4): 197-201, 1994.
Article in English | MEDLINE | ID: mdl-9136238

ABSTRACT

Sixty-eight patients with primary glaucoma involving 68 eyes were divided into two groups: Group I eyes were subjected to trabeculectomy (n = 38) and Group II eyes underwent trabeculectomy followed by subconjunctival injections of 5-fluorouracil (35 mg) (n = 30). After one year follow-up, Group I eyes exhibited reduction of mean intra-ocular tension from 45.7 mm Hg (pre-operative) to 16 mm Hg; optic disc cupping remained unchanged and 24/38 eyes (63%) were found to have field defects (19/38 i.e. 50% had preoperative field defects.) Group II eyes showed a reduction of mean intra-ocular pressure from 47.3 mmHg to 9.3 mmHg after one year. Mean cup disc ratio was lowered from 0.50:1 to 0.46:1 and 17/30 eyes (57%) which had field defects initially continued to exhibit the same. Complications in Group I and II eyes were shallow anterior chamber [8/38 eyes (21%) from Group I and 8/30 eyes (26%) from Group II], posterior synechiae formation in 10/38 eyes (26%) and 8/30 eyes (26%) and cataract progression in 13/38 eyes (34%) and 12/30 eyes (40%) respectively; only Group II eyes had transient superficial keratitis in 9/30 eyes (30%) and thin blebs in 6/30 eyes (20%). The use of 5-fluorouracil after trabeculectomy for primary glaucoma resulted in lowering of intra-ocular pressure, eliminated the need for antiglaucoma medications post-operatively, reduced the galucomatous cup size, and prevented progression of field loss without having a significantly increased complication rate.


Subject(s)
Antimetabolites/therapeutic use , Fluorouracil/therapeutic use , Glaucoma/drug therapy , Trabeculectomy , Adult , Aged , Aged, 80 and over , Antimetabolites/pharmacology , Fluorouracil/pharmacology , Glaucoma/surgery , Humans , Intraocular Pressure/drug effects , Middle Aged
16.
Indian J Exp Biol ; 32(7): 450-7, 1994 Jul.
Article in English | MEDLINE | ID: mdl-7959919

ABSTRACT

Isomers of fibroblast growth factor and members of the transforming growth factor beta family have been identified as potent mesoderm inducing factors, particularly in amphibians. Activins belonging to the latter group are capable of inducing all types of mesoderm. Inhibins, also belonging to the same family of proteins have an exactly opposite biological action than activins in the adult organism. We have examined the effects of human seminal plasma inhibin on the early development of the chick embryo, where also activins appear to be important in mesoderm induction. Contrary to expectations, inhibin brought about stimulation of development of somites and heart, structures of mesodermal origin, and increase in the body length in more than 50% of the treated chick blastoderms. A synthetic fragment of human seminal plasma inhibin, a nonapeptide fragment of C-terminal end, also exhibited similar effects. In some cases the treatments resulted in completely abnormal development while in some increase in the number of somites was associated with abnormality in the anterior region. Our results demonstrate that human seminal plasma inhibin does not act as an inhibitor of mesoderm induction in the chick embryo but in amniotes inhibin-related molecules may have a role as mesoderm enhancers.


Subject(s)
Inhibins/pharmacology , Mesoderm/drug effects , Oligopeptides/pharmacology , Peptide Fragments/pharmacology , Semen/chemistry , Amino Acid Sequence , Animals , Chick Embryo , Humans , Inhibins/chemistry , Male , Molecular Sequence Data
17.
Indian J Biochem Biophys ; 29(6): 498-507, 1992 Dec.
Article in English | MEDLINE | ID: mdl-1294469

ABSTRACT

The composition of soluble eye lens proteins from four chondropterygiian and fourteen teleostean fishes were analyzed for heterogeneity in MW and pI. Lens proteins from all the fish species studies are distributed in the pI range 4.3-9.0 with polypeptides in the range 17,500-31,000 Da. Phylogenetic trees are constructed based on the observations.


Subject(s)
Crystallins/isolation & purification , Fishes/genetics , Phylogeny , Animals , Crystallins/chemistry , Electrophoresis, Polyacrylamide Gel , Isoelectric Focusing , Molecular Weight
18.
Indian J Biochem Biophys ; 27(5): 280-3, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2079332

ABSTRACT

High resolution thermal denaturation (HRTD) profiles of the DNAs of six related millets, oat and rice showed several maxima and shoulders skewed towards the GC-rich side. Linear regression and correlation analyses exhibited no correlation between the repetitive DNA content/nuclear DNA content and the number of peaks, while there existed a very good correlation between delta T and repetitive DNA content/nuclear DNA content indicating that increase in repetitive DNA content has resulted in a greater sequence heterogeneity in these DNAs. In addition, specific melting characteristics of each of the eight plant DNAs were identified, which showed species specificity.


Subject(s)
DNA/genetics , Plants/genetics , DNA/isolation & purification , Hot Temperature , Nucleic Acid Denaturation , Species Specificity
19.
J Steroid Biochem ; 35(3-4): 487-94, 1990 Mar.
Article in English | MEDLINE | ID: mdl-2325415

ABSTRACT

High concentrations of pregnenolone and its sulfate have been found in several areas of rat and human brain and seem to be controlled by local mechanisms. In the present experiments we have demonstrated pregnenolone binding sites in the cytosolic fraction of the rat olfactory bulb. The pregnenolone binding component showed a Kd = 2.34 +/- 0.66 x 10(-7) M and Nmax = 7.25 +/- 1.20 pmol/mg protein. Pregnenolone, pregnenolone sulfate and 17OH-pregnenolone competed equally for the binding sites while other steroids were less competitive. Protease and trypsin inhibited binding by 48 and 60% respectively. Sucrose density gradient analysis showed a minor peak at 4.6 s and a major one at 3.6 s. After gel filtration chromatography the pregnenolone binding component appeared as 2 peaks corresponding to molecular weights of approximately 150 and 220 kDa. Heating at 60 degrees C increased binding by 150%. These results indicate that the olfactory bulb pregnenolone binding component is complex in nature. Rat plasma also bound pregnenolone. Plasma binding sites could be partially differentiated from those in the olfactory bulb on the basis of susceptibility to lipoprotein lipase, effect of heating and mobility during polyacrylamide gel electrophoresis.


Subject(s)
Olfactory Bulb/metabolism , Pregnenolone/metabolism , Animals , Binding Sites , Centrifugation, Density Gradient , Chromatography, Gel , Hot Temperature , Male , Rats , Rats, Inbred Strains
20.
Brain Res ; 463(2): 403-6, 1988 Nov 01.
Article in English | MEDLINE | ID: mdl-3196929

ABSTRACT

We have previously detected progesterone, dehydroepiandrosterone, androstenedione, testosterone and estrone in rat retina. The present experiments show that the presence of these steroids in the retina may not be due to local biosynthesis. On the other hand, they demonstrate considerable 5 alpha-reductase and 3 beta-hydroxysteroid dehydrogenase activities in the rat retina. The significance of these activities in the retina is discussed.


Subject(s)
Retina/metabolism , Steroids/metabolism , 3-Hydroxysteroid Dehydrogenases/metabolism , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/metabolism , Androstenedione/metabolism , Animals , Male , Pregnenolone/metabolism , Progesterone/metabolism , Rats , Rats, Inbred Strains , Testosterone/metabolism
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