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1.
Andrology ; 6(5): 680-689, 2018 09.
Article in English | MEDLINE | ID: mdl-29959832

ABSTRACT

Condensed sperm chromatin is a prerequisite for natural fertilization. Some reports suggested the prevalence of chromatin condensation defects in teratozoospermia cases with head anomalies; conversely, earlier studies exemplified its occurrence in morphologically normal spermatozoa too. The aim of this study was to compare the condensation defects in correlation with head anomalies among different groups of subfertile males and its impact on the rate of fertilization in assisted reproduction procedures. Ultrastructure analysis of spermatozoa through scanning electron microscopy and atomic force microscopy could facilitate an in-depth evaluation of sperm morphology. Nuclear condensation defects (%) in spermatozoa were analyzed in 666 subjects, and its effect on the rate of fertilization was analyzed in 116 IVF and 90 intracytoplasmic sperm injection cases. There was no correlation of condensation defects with head anomalies (%). Student's t-test showed no significant changes in mean values of condensation defects in abnormal semen samples in comparison with the normal group. Condensation defects were observed in normal spermatozoa too, which was negatively associated with the rate of fertilization in IVF (p < 0.01), but intracytoplasmic sperm injection outcome remained unaffected. Ultrastructure study revealed sperm morphological features in height, amplitude, and three-dimensional views in atomic force microscopy images presenting surface topography, roughness property of head, and compact arrangement of mitochondria over axoneme with height profile at nanoscale. In pathological forms, surface roughness and nuclear thickness were marked higher than the normal spermatozoa. Thus, percentage of normal spermatozoa with condensation defects could be a predictive factor for the rate of fertilization in IVF. From diverse shapes of nucleus in AFM imaging, it could be predicted that defective nuclear shaping might be impeding the activity of some proteins/ biological motors, those regulate the proper Golgi spreading over peri-nuclear theca.


Subject(s)
Infertility, Male/pathology , Spermatozoa/pathology , Adult , Chromatin Assembly and Disassembly , Fertilization in Vitro , Humans , Infertility, Male/physiopathology , Male , Microscopy , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Retrospective Studies , Semen Analysis , Sperm Head/pathology , Sperm Head/ultrastructure , Sperm Injections, Intracytoplasmic , Spermatozoa/ultrastructure
2.
Int J Sports Med ; 37(4): 261-6, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26837934

ABSTRACT

We examined the association of cardiorespiratory fitness with metabolic syndrome in overweight/obese postmenopausal African-American women. Pooled baseline data on 170 African-American women from 2 exercise trials were examined. Metabolic syndrome was defined as at least 3 of the following: abdominal obesity, glucose intolerance, hypertension, low high-density lipoprotein cholesterol (HDL-C), and high triglycerides. Cardiorespiratory fitness (VO2peak) was determined using the Bruce treadmill protocol and categorized as: Very Low (VLCRF<18 mL·kg(-1) min(-1)), Low (LCRF=18.0-220-22-22.0 mL·kg(-1) min(-1)), and Moderate (MCRF>22.0 mL·kg(-1) min(-1)). Associations of metabolic syndrome with cardiorespiratory fitness were analyzed using one-way ANOVA and linear regression. VO2peak was significantly lower in the VLCRF compared to the MCRF group. Lower cardiorespiratory fitness was associated with higher prevalence of metabolic syndrome, abdominal obesity, hypertriglyceridemia, and low HDL among overweight/obese postmenopausal African-American women. In fully adjusted models, higher waist circumference and triglycerides were associated with lower VO2peak levels (P<0.01) and higher HDL-C was associated with higher VO2peak levels (P=0.03). Overweight/obese postmenopausal African-American women with very low cardiorespiratory fitness are more likely to have metabolic syndrome, higher body mass index, and unhealthier levels of certain metabolic syndrome components than women with moderate cardiorespiratory fitness.


Subject(s)
Metabolic Syndrome/physiopathology , Physical Fitness , Postmenopause , Black or African American , Body Composition , Body Mass Index , Cholesterol, HDL/blood , District of Columbia , Exercise Test , Female , Glucose Intolerance , Heart Rate , Humans , Hypertension/physiopathology , Metabolic Syndrome/ethnology , Middle Aged , Obesity, Abdominal/physiopathology , Overweight/physiopathology , Oxygen Consumption , Triglycerides/blood , Waist Circumference
4.
Haemophilia ; 17(5): 737-42, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21699629

ABSTRACT

Optivate® is a high-purity FVIII/VWF product. Its safety, tolerability and efficacy in subjects ≥ 12 years have been demonstrated. This study was undertaken to assess Optivate® in children with haemophilia A. Twenty-five children, including one PUP (previously untreated patient), aged 1-6 years (mean 4.67 years) were treated with Optivate® for 26 weeks. Inhibitors were assessed every 3 months and viral status at the study start and end. Prophylaxis was used by five boys and on demand by twenty. The mean number of bleeds in the study was lower compared to the same period pre-study (12.0/child vs. 16.2/child), with fewer bleeds (P < 0.05) in the prophylactic subgroup (8.0/child) compared with the on-demand sub-group (13.4/child). Fourteen major bleeds were reported, all by the on-demand sub-group. Children on prophylaxis were administered a mean of 59.4 infusions; on-demand group 35.1 infusions. A total of 998 infusions were used with a mean dose of 29.1 IU kg⁻¹, and a mean of 38.6 exposure days (ED). Children < 4 years used higher doses, and reported fewer bleeds than older children. Children's Parents/Guardians rated Optivate® as helpful or very helpful in controlling 97.5% of bleeds by the prophylactic group, and in 98.5% of the bleeds in the on-demand group. Only 5 of 101 ADRs were treatment-related events (5%), all were mild and non-serious. There were no clinically significant changes in vital signs, viral transmissions or inhibitors. In young children Optivate® was well tolerated, safe and efficacious.


Subject(s)
Coagulants/therapeutic use , Factor VIII/therapeutic use , Hemophilia A/drug therapy , von Willebrand Factor/therapeutic use , Analysis of Variance , Child , Child, Preschool , Drug Combinations , Hemorrhage/prevention & control , Humans , Male , Outcome Assessment, Health Care , Prospective Studies
5.
Haemophilia ; 17(3): 428-32, 2011 May.
Article in English | MEDLINE | ID: mdl-21371182

ABSTRACT

The efficacy and safety of Optivate(®) was assessed in 23 surgical operations, orthopaedic (12) including 5 revision arthroplasties, ophthalmic (1), ENT (1), dental (6), liver biopsy (2), and removal of portacath (1) on 15 teenagers and adults with severe haemophilia A. The preoperative dose was calculated to raise the FVIII concentration to 100 IU dL(-1). Subsequent doses were targeted to maintain at least 50 IU dL(-1). There were 11 major and 12 minor operations categorized as receiving intensive replacement therapy for ≥ 5 days or < 5 days respectively. The median preoperative dose was 50.4 (range 18.2-88.2) IU kg(-1). The median incremental recovery based on this first dose in 10 procedures (5 patients) was 2.9 (range 2.4-3.4 IU dL(-1) ) per IU kg(-1). The daily doses decreased during the first 4 days of the study. The patients in this study received 173 infusions in total. Outcome was 'good' or 'excellent' for 19 (83%) of 23 operations, 'uncertain' in three procedures because an antifibrinolytic agent was used as well and for one procedure outcome was not assessed. Tolerance was good. There were no excessive bleeds, no inhibitors and no virus transmissions.


Subject(s)
Blood Loss, Surgical/prevention & control , Factor VIII/therapeutic use , Hemophilia A/drug therapy , Hemophilia A/surgery , Hemostasis, Surgical/methods , Hemostatics/therapeutic use , von Willebrand Factor/therapeutic use , Adolescent , Adult , Drug Combinations , Humans , Middle Aged , Perioperative Care/methods , Preoperative Care/methods , Young Adult
6.
Haemophilia ; 17(3): 456-62, 2011 May.
Article in English | MEDLINE | ID: mdl-21371184

ABSTRACT

Factor VIII (FVIII) concentrates have revolutionized the treatment of patients with haemophilia A. Concerns over the transmission of viral infections through these products have been addressed through stringent, donor-screening procedures and robust antiviral manufacturing steps. Bio Products Laboratory has developed a high-purity FVIII product with von Willebrand factor, Optivate(®). Its safety, tolerability and efficacy as prophylaxis and treatment of bleeds have been established in long-term studies. Seventy previously treated patients with severe haemophilia A, with ≥ 20 exposure days, were recruited into two long-term, multicentre, open-label studies. The protocols were virtually identical. Patients received Optivate(®) either prophylactically or on-demand. A mean of 159.0 EDs were experienced over 11,320 infusions. Under both conditions, Optivate(®) was well tolerated. Only 10% of patients experienced a treatment-related adverse event; the most commonly reported were headache (4% of patients) and dizziness (3% of patients). The mean number of bleeds/patient over the 2 year treatment period was 23.5 during prophylactic use and 70.4 during on-demand use. In patients treated prophylactically, clinical responses to breakthrough bleeds were rated by physicians as excellent or good and as very helpful or helpful by patients in 95% of bleeds. Clinical responses for on-demand patients were rated as excellent or good by physicians and helpful or very helpful by the patients for 91% of bleeds. There were no viral transmissions or inhibitors. The studies confirm the clinical efficacy and safety of Optivate(®) in both prophylactic and on-demand management of patients with haemophilia A.


Subject(s)
Factor VIII/therapeutic use , Hemophilia A/drug therapy , Hemorrhage/drug therapy , Hemostatics/therapeutic use , von Willebrand Factor/therapeutic use , Adolescent , Adult , Aged , Child , Drug Combinations , Factor VIII/administration & dosage , Factor VIII/adverse effects , Hemorrhage/prevention & control , Hemostatics/administration & dosage , Hemostatics/adverse effects , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Young Adult , von Willebrand Factor/administration & dosage , von Willebrand Factor/adverse effects
7.
Haemophilia ; 17(2): 185-90, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21070496

ABSTRACT

Optivate(®) is a high purity factor VIII/von Willebrand factor (FVIII/VWF) concentrate, which is manufactured using two antiviral processes: solvent/detergent and terminal dry heating (80 °C for 72 h). A multicentre, non-randomized open-label study in 15 patients was conducted to test the pharmacokinetics (PK) of Optivate(®). PK variables were analysed for the patients' prior FVIII product (PK1), their first dose of Optivate(®) (PK2) and at 3 months therapy (PK3). Mean non-compartmental half-lives (h) were 14.1, 12.4 and 12.1, respectively (P = 0.45), mean clearances (mL h(-1) kg(-1)) were 3.6, 3.2 and 3.1, respectively (P = 0.051), MRTs (h) were 19.0, 17.3 and 17.4, respectively (P = 0.39) and mean AUC(0-48h) (h IU mL(-1)) were 14.3, 15.4 and 16.6, respectively (P = 0.051) and mean AUC(0-∞) (h IU mL(-1)) were 15.9, 16.4 and 17.9, respectively (P = 0.18). The recovery data from this PK study was aggregated with recovery data collected from another study, with similar design but devoid of the other PK measurements. A total of 309 recoveries were conducted in 70 patients. The overall mean recovery per subject across 27 Optivate(®) batches was 2.7 IU dL(-1) per IU kg(-1). There were no clinical differences between Optivate(®) and other FVIII products, and except for volume of distribution (Vd), no statistically significant differences were seen with respect to any of the other PK variables, or in recovery between weeks 0 and 12. Therefore, the PK of FVIII is not affected by the processes used to manufacture Optivate(®), which can be expected to be effective in the management of patients with haemophilia A.


Subject(s)
Factor VIII/pharmacokinetics , Hemophilia A/drug therapy , von Willebrand Factor/pharmacokinetics , Adolescent , Adult , Aged , Child , Humans , Metabolic Clearance Rate , Middle Aged , Prospective Studies , Young Adult
8.
Clin Exp Immunol ; 162(3): 510-5, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21070209

ABSTRACT

This open-label multi-centre study evaluated a new intravenous immunoglobulin, Gammaplex®, in the treatment of 50 patients with primary immunodeficiency and significant hypogammglobulinaemia. Patients treated previously with other intravenous immunoglobulins received Gammaplex® on their same infusion schedule for 1 year; 22 were on a 21-day and 28 on a 28-day regimen (300-800 mg/kg/infusion). There were no serious, acute bacterial infections, whereas six subjects (12·0%) had at least one such infection in the 6 months before enrollment. Forty subjects (80·0%) had at least one non-serious infection; the median number of infective episodes per subject per year was 3·07. Antibiotics were taken by 38 subjects therapeutically and prophylactically by 16 at some time. Fewer than half (46·0%) missed any time off work or school because of infection or other illness. Trough immunoglobulin (Ig)G levels were above 6·00 g/l in all subjects at all assessments after 15 weeks with two exceptions. Overall, 21·2% of infusions were associated with an adverse event up to 72 h after infusion. The frequency of adverse events increased with infusion rate. Headache was the most common product-related adverse event (7·5% of 703 infusions). In conclusion, Gammaplex® is effective in primary immunodeficiency and is well tolerated.


Subject(s)
Common Variable Immunodeficiency/drug therapy , Immunoglobulins, Intravenous/administration & dosage , Adolescent , Adult , Aged , Child , Clinical Protocols , Common Variable Immunodeficiency/epidemiology , Common Variable Immunodeficiency/physiopathology , Female , Fever , Follow-Up Studies , Hospitalization , Humans , Immunoglobulins, Intravenous/adverse effects , Immunoglobulins, Intravenous/pharmacokinetics , Infections , Male , Middle Aged
9.
J Fish Biol ; 77(5): 1096-113, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21039493

ABSTRACT

Embryonic stem (ES)-like cells were derived from mid-blastula stage embryos of a freshwater fish, catla Catla catla, under feeder-free condition and designated as CCES cells. The conditioned media was optimized with 10% foetal bovine serum (FBS), fish embryo extract (FEE) having 100 µg ml(-1) protein concentration, 15 ng ml(-1) basic fibroblast growth factor (bFGF) and basic media containing Leibovitz-15, DMEM with 4·5 g l(-1) glucose and Ham's F12 (LDF) in 2:1:1 ratio using a primary culture of CCES cells. Cells attached to gelatin-coated plates after 24 h of seeding and ES-like colonies were obtained at day 5 onwards. A stable cell culture was obtained after passage 10 and further maintained up to passage 44. These cells were characterized by their typical morphology, high alkaline phosphatase activity, positive expression of cell-surface antigen SSEA-1, transcription factor Oct4, germ cell marker vasa and consistent karyotype up to extended periods. The undifferentiated state was confirmed by their ability to form embryoid bodies and their differentiation potential.


Subject(s)
Carps , Embryonic Stem Cells/cytology , Animals , Cell Culture Techniques , Cell Differentiation , Cells, Cultured , Culture Media, Conditioned
10.
Org Biomol Chem ; 8(6): 1271-4, 2010 Mar 21.
Article in English | MEDLINE | ID: mdl-20204192

ABSTRACT

A polymer-bound alpha,beta-methylene-beta-triphosphitylating reagent was synthesized and subjected to reactions with unprotected nucleosides, followed by oxidation, deprotection of cyanoethoxy groups, and acidic cleavage to afford nucleoside 5'-O-alpha,beta-methylene-beta-triphosphates. Among all the compounds, cytidine 5'-O-alpha,beta-methylene-beta-triphosphate inhibited RNase H activity of HIV-1 reverse transcriptase with a K(i) value of 225 microM.


Subject(s)
HIV Reverse Transcriptase/antagonists & inhibitors , HIV-1/enzymology , Nucleotides/chemical synthesis , Nucleotides/pharmacology , Reverse Transcriptase Inhibitors/chemical synthesis , Reverse Transcriptase Inhibitors/pharmacology , HIV Reverse Transcriptase/metabolism , Kinetics , Nucleotides/chemistry , Reverse Transcriptase Inhibitors/chemistry , Ribonuclease H/antagonists & inhibitors
11.
Transfus Med ; 20(4): 244-9, 2010 Aug 01.
Article in English | MEDLINE | ID: mdl-20230532

ABSTRACT

The aim of the study was to document the incidence of adverse reactions (ADRs) in subjects undergoing therapeutic plasma exchange with human albumin 4.5% solution (Zenalb 4.5) and to explore whether there were any differences in tolerability with a change from UK to US plasma and a subsequent manufacturing modification. Zenalb 4.5 was initially manufactured from recovered plasma from UK blood donations and later from source plasma from US donors. The modification was a salt diafiltration step. A prospective survey was conducted at three UK aphaeresis units; data from 154 subjects undergoing 1195 plasma exchanges using Zenalb 4.5 were collected. Adverse events with at least a possible relationship to treatment were recorded. There were 20 ADRs per 1195 exchanges (1.7%), experienced by 14 subjects (9.1%). The most common reaction was rigours in 17 exchanges (1.4%) and 12 subjects (7.8%). ADRs occurred in 0.8% (2/250) of plasma exchanges with UK plasma, 0.2% (1/539) using US plasma/original manufacturing method, 4.3% (16/370) using US plasma/modified method and 12.5% (1/8) using US plasma/mixed original and modified methods. Data were incomplete for the remaining 28 exchanges, but no ADRs were reported. Moreover, 17 ADRs occurred over a 14-month period and involved 10 batches manufactured from US plasma (1 original, 9 by modified method). The incidence then returned to the previously lower level. There was no explanation for this cluster of events. Overall, there was no evidence that plasma source or manufacturing method affected tolerability and it was concluded that human albumin 4.5% solution (Zenalb 4.5) is well tolerated during plasma exchange therapy.


Subject(s)
Plasma Exchange/methods , Serum Albumin/adverse effects , Adolescent , Adult , Aged , Aged, 80 and over , Child , Diagnosis-Related Groups , Drug Hypersensitivity/etiology , Female , Fever/etiology , Hemodynamics , Humans , Male , Middle Aged , Plasma Exchange/adverse effects , Prospective Studies , Risk Factors , Serum Albumin/administration & dosage , Serum Albumin/isolation & purification , United Kingdom , United States , Young Adult
13.
Clin Exp Immunol ; 150(1): 30-41, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17680827

ABSTRACT

Anti-D is given routinely to pregnant RhD-negative women to prevent haemolytic disease of the fetus and newborn. To overcome the potential drawbacks associated with plasma-derived products, monoclonal and recombinant forms of anti-D have been developed. The ability of two such antibodies, BRAD-3/5 monoclonal anti-D IgG (MAD) and rBRAD-3/5 recombinant anti-D IgG (RAD), to clear RhD-positive erythrocytes from the circulation was compared using a dual radiolabelling technique. Six RhD-positive males received autologous erythrocytes radiolabelled with (99m)Tc and (51)Cr and coated ex vivo with MAD and RAD. Blood samples were collected up to 1 h following intravenous injection, and percentage dose of radioactivity in the samples determined. Three different levels of coating were used on three separate occasions. No significant differences between MAD and RAD were observed in the initial clearance rate constant at any dose level. The log[activity]-time clearance plots were curved, showing a reduction in the clearance rate constant with time. This reduction was more marked for RAD than for MAD. The results support a dynamic model for the clearance of antibody-coated erythrocytes that may have wider relevance for the therapeutic use of antibodies.


Subject(s)
Erythrocytes/immunology , Hemolysis/immunology , Isoantibodies/immunology , Rh-Hr Blood-Group System/blood , Adult , Antibodies, Monoclonal/immunology , Chromium Radioisotopes/blood , Cross-Over Studies , Dose-Response Relationship, Immunologic , Humans , Immunoglobulin G/blood , Male , Recombinant Proteins/immunology , Rh-Hr Blood-Group System/immunology , Rho(D) Immune Globulin , Spleen/immunology , Technetium/blood
14.
Pharmacoepidemiol Drug Saf ; 13(4): 243-52, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15255091

ABSTRACT

PURPOSE: To assess the safety of a highly purified, plasma-derived factor VIII concentrate (Replenate) in routine clinical use. METHODS: Following guidelines entitled safety assessment of marketed medicines (SAMM), safety data were collected in the UK on 194 patients who received an estimated 47.6 million IU of Replenate. This population included 47 patients undergoing 53 surgical operations or dental extractions. RESULTS: The study detected four cases of new factor VIII inhibitor development and twelve other adverse events, five that were unrelated to the product, five whose causality was unknown, one that was possibly product-related and one case due to possible lack of efficacy. Only one of these cases had been notified to the manufacturer through conventional spontaneous reporting procedures. Three patients were switched from Replenate as a result of an adverse event (one case of infusion site irritation and two cases of a rise in titre of an existing inhibitor), but no unexpected adverse reactions were noted and there were no reports of virus transmission. The median factor VIII recovery value was 2.17 IU/dl per IU/kg, but recovery was shown to be dependent on several variables, namely inhibitor status, treatment centre and the patient's body weight. The median factor VIII recovery in inhibitor-free patients was 2.28 IU/dl per IU/kg (range: 1.20-6.62). CONCLUSIONS: The study confirms that Replenate is well tolerated by the majority of patients in routine clinical practice.


Subject(s)
Factor VIII/adverse effects , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Colectomy , Craniotomy , Cross-Sectional Studies , Female , Hepatitis Viruses/isolation & purification , Humans , Laparotomy , Male , Middle Aged , Retrospective Studies , Safety , Surveys and Questionnaires
15.
Pharmacoepidemiol Drug Saf ; 13(3): 187-95, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15072119

ABSTRACT

PURPOSE: To assess the safety of a plasma-derived highly purified factor IX concentrate (Replenine) in routine clinical use. METHODS: Following guidelines entitled Safety Assessment of Marketed Medicines (SAMM), safety data were collected in the UK by retrospective review of the hospital notes of 114 patients who received an estimated 14.8 million IU of Replenine. Included were 40 patients undergoing 44 surgical procedures or dental extractions [corrected]. RESULTS: The study detected a total of nine adverse events (AEs), four of which were possibly product-related, four that were unrelated to the product and one whose causality was unknown. None of these cases had been notified to the manufacturer through conventional spontaneous reporting procedures. One patient was switched from Replenine because of infusion site irritation, but no unexpected adverse reactions were noted. There were no reports of virus transmission or new factor IX inhibitor development. The mean factor IX recovery value was 1.44 IU/dl per IU/kg (95%CI: 1.31-1.57 IU/dl per IU/kg). CONCLUSIONS: The study was a practical application of the SAMM guidelines to the collection of pharmacovigilance data on patients with Haemophilia B. Replenine is well tolerated in routine clinical practice.


Subject(s)
Factor IX/adverse effects , Product Surveillance, Postmarketing , Retrospective Studies , Adult , Data Collection/methods , Demography , Drug Administration Schedule , Factor IX/administration & dosage , Factor IX/therapeutic use , Female , Hemophilia A/blood , Hemophilia A/complications , Hemophilia A/drug therapy , Hemophilia B/blood , Hemophilia B/complications , Hemophilia B/drug therapy , Humans , Infusions, Intravenous , Injections, Intravenous , Male , Patient Selection , Pharmacology, Clinical , Surgical Procedures, Operative/classification , Surveys and Questionnaires , Treatment Outcome , United Kingdom , Virus Diseases/complications , Virus Diseases/diagnosis , Virus Diseases/drug therapy
16.
Biochemistry ; 40(38): 11525-32, 2001 Sep 25.
Article in English | MEDLINE | ID: mdl-11560501

ABSTRACT

We present here the first report of a hydrophilic peptidic inhibitor, ATBI, from an extremophilic Bacillus sp. exhibiting a two-step inhibition mechanism against the aspartic proteases, pepsin and F-prot from Aspergillus saitoi. Kinetic analysis shows that these proteases are competitively inhibited by ATBI. The progress curves are time-dependent and consistent with slow-tight binding inhibition: E + I right arrow over left arrow (k(3), k(4)) EI right arrow over left arrow (k(5), k(6)) EI. The K(i) values for the first reversible complex (EI) of ATBI with pepsin and F-prot were (17 +/- 0.5) x 10(-9) M and (3.2 +/- 0.6) x 10(-6) M, whereas the overall inhibition constant K(i) values were (55 +/- 0.5) x 10(-12) M and (5.2 +/- 0.6) x 10(-8) M, respectively. The rate constant k(5) revealed a faster isomerization of EI for F-prot [(2.3 +/- 0.4) x 10(-3) s(-1)] than pepsin [(7.7 +/- 0.3) x 10(-4) s(-1)]. However, ATBI dissociated from the tight enzyme-inhibitor complex (EI) of F-prot faster [(3.8 +/- 0.5) x 10(-5) s(-1)] than pepsin [(2.5 +/- 0.4) x 10(-6) s(-1)]. Comparative analysis of the kinetic parameters with pepstatin, the known inhibitor of pepsin, revealed a higher value of k(5)/k(6) for ATBI. The binding of the inhibitor with the aspartic proteases and the subsequent conformational changes induced were monitored by exploiting the intrinsic tryptophanyl fluorescence. The rate constants derived from the fluorescence data were in agreement with those obtained from the kinetic analysis; therefore, the induced conformational changes were correlated to the isomerization of EI to EI. Chemical modification of the Asp or Glu by WRK and Lys residues by TNBS abolished the antiproteolytic activity and revealed the involvement of two carboxyl groups and one amine group of ATBI in the enzymatic inactivation.


Subject(s)
Aspartic Acid Endopeptidases/chemistry , Aspartic Acid Endopeptidases/metabolism , Bacillus/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/pharmacology , Protease Inhibitors/chemistry , Aspergillus/enzymology , Bacillus/growth & development , Bacterial Proteins/isolation & purification , Kinetics , Least-Squares Analysis , Models, Chemical , Pepsin A/antagonists & inhibitors , Pepsin A/chemistry , Pepstatins/chemistry , Pepstatins/pharmacology , Protease Inhibitors/pharmacology
17.
Bioconjug Chem ; 12(5): 684-90, 2001.
Article in English | MEDLINE | ID: mdl-11562186

ABSTRACT

We present herein details pertaining to the preparation of bioconjugates of colloidal gold with aspartic protease from the fungus Aspergillus saitoi (F-prot) and their characterization and enzymatic activity. Simple mixing of the colloidal gold and protein solutions under protein-friendly conditions (pH = 3) followed by centrifugation (to remove uncomplexed gold nanoparticles and protein molecules) results in the formation of the fungal protease-gold nanoparticle conjugates. The protein-gold nanoparticle bioconjugate was redispersed in buffer solution and indicated the formation of efficient bioconjugates with intact native protein structures. The bioconjugates in solution were characterized by UV-vis spectroscopy, fluorescence spectroscopy, and biocatalytic activity measurements while drop-dried bioconjugate films on Si (111) substrates were characterized by scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX), and X-ray diffraction (XRD) measurements. Microscopy images do show some aggregate formation, but the intactness of the native structure of the enzyme in the bioconjugate material was verified by fluorescence and biocatalytic activity measurements. The enzyme retains substantial biocatalytic activity in the bioconjugate material and was comparable to that of free enzyme in solution.


Subject(s)
Aspartic Acid Endopeptidases/chemistry , Gold Colloid/chemistry , Aspartic Acid Endopeptidases/metabolism , Aspergillus/enzymology , Catalysis , Drug Stability , Fungal Proteins/chemistry , Microscopy, Electron, Scanning/methods , Protein Structure, Tertiary , Spectrum Analysis , Staining and Labeling , X-Ray Diffraction
18.
Vox Sang ; 80(3): 151-8, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11449954

ABSTRACT

BACKGROUND AND OBJECTIVES: The tolerability and pharmacokinetics of a solvent/detergent-treated intramuscular immunoglobulin were compared with those of the standard product. MATERIALS AND METHODS: Single, 750-mg intramuscular (i.m.) injections were administered to a total of 36 healthy individuals: 23 in a double-blind trial and 13 in an open trial. Changes in specific serum hepatitis A and hepatitis B antibodies were monitored for a period of up to 3 months postinjection. RESULTS: No serious adverse reactions were reported, and the bioavailability of the solvent/detergent-treated preparation was equivalent to that of the standard i.m. immunoglobulin. CONCLUSION: There is no evidence that solvent/detergent treatment alters the pharmacokinetics or tolerance of human normal immunoglobulin, but it offers additional assurance against potential virus transmission.


Subject(s)
Detergents/pharmacology , Immunoglobulins, Intravenous/isolation & purification , Solvents/pharmacology , Adolescent , Adult , Aged , Area Under Curve , Biological Availability , Double-Blind Method , Female , Hepatitis A Antibodies , Hepatitis Antibodies/blood , Hepatitis B Antibodies/blood , Humans , Immunization, Passive , Immunoglobulins, Intravenous/administration & dosage , Immunoglobulins, Intravenous/adverse effects , Immunoglobulins, Intravenous/drug effects , Immunoglobulins, Intravenous/pharmacokinetics , Injections, Intramuscular , Male , Middle Aged , Organophosphates/administration & dosage , Organophosphates/pharmacology , Safety
19.
Antimicrob Agents Chemother ; 45(7): 2008-17, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11408216

ABSTRACT

A novel bifunctional inhibitor (ATBI) from an extremophilic Bacillus sp. exhibiting an activity against phytopathogenic fungi, including Alternaria, Aspergillus, Curvularia, Colletotricum, Fusarium, and Phomopsis species, and the saprophytic fungus Trichoderma sp. has been investigated. The 50% inhibitory concentrations of ATBI ranged from 0.30 to 5.9 microg/ml, whereas the MIC varied from 0.60 to 3.5 microg/ml for the fungal growth inhibition. The negative charge and the absence of periodic secondary structure in ATBI suggested an alternative mechanism for fungal growth inhibition. Rescue of fungal growth inhibition by the hydrolytic products of xylanase and aspartic protease indicated the involvement of these enzymes in cellular growth. The chemical modification of Asp or Glu or Lys residues of ATBI by 2,4,6-trinitrobenzenesulfonic acid and Woodward's reagent K, respectively, abolished its antifungal activity. In addition, ATBI also inhibited xylanase and aspartic protease competitively, with K(i) values 1.75 and 3.25 microM, respectively. Our discovery led us to envisage a paradigm shift in the concept of fungal growth inhibition for the role of antixylanolytic activity. Here we report for the first time a novel class of antifungal peptide, exhibiting bifunctional inhibitory activity.


Subject(s)
Antifungal Agents/pharmacology , Aspartic Acid Endopeptidases/antagonists & inhibitors , Bacterial Proteins/pharmacology , Enzyme Inhibitors/pharmacology , Fungi/drug effects , Xylosidases/antagonists & inhibitors , Alternaria/drug effects , Alternaria/growth & development , Antifungal Agents/chemistry , Aspartic Acid Endopeptidases/metabolism , Aspergillus/drug effects , Aspergillus/growth & development , Bacillus/chemistry , Bacterial Proteins/chemistry , Colletotrichum/drug effects , Colletotrichum/growth & development , Kinetics , Microbial Sensitivity Tests , Peptides/chemistry , Peptides/isolation & purification , Peptides/pharmacology , Xylan Endo-1,3-beta-Xylosidase , Xylosidases/metabolism
20.
J Biol Chem ; 276(4): 2487-93, 2001 Jan 26.
Article in English | MEDLINE | ID: mdl-11042202

ABSTRACT

The active site cleft of the HIV-1 protease (PR) is bound by two identical conformationally mobile loops known as flaps, which are important for substrate binding and catalysis. The present article reports, for the first time, an HIV-1 PR inhibitor, ATBI, from an extremophilic Bacillus sp. The inhibitor is found to be a hydrophilic peptide with Mr of 1147, and an amino acid sequence of Ala-Gly-Lys-Lys-Asp-Asp-Asp-Asp-Pro-Pro-Glu. Sequence homology exhibited no similarity with the reported peptidic inhibitors of HIV-1 PR. Investigation of the kinetics of the enzyme-inhibitor interactions revealed that ATBI is a noncompetitive and tight binding inhibitor with the IC(50) and K(i) values 18.0 and 17.8 nm, respectively. The binding of the inhibitor with the enzyme and the subsequent induction of the localized conformational changes in the flap region of the HIV-1 PR were monitored by exploiting the intrinsic fluorescence of the surface exposed Trp-42 residues, which are present at the proximity of the flaps. We have demonstrated by fluorescence and circular dichroism studies that ATBI binds in the active site of the HIV-1 PR and thereby leads to the inactivation of the enzyme. Based on our results, we propose that the inactivation is due to the reorganization of the flaps impairing its flexibility leading toward inaccessibility of the substrate to the active site of the enzyme.


Subject(s)
Bacillus , Bacterial Proteins/pharmacology , HIV Protease Inhibitors/pharmacology , HIV-1/enzymology , Oligopeptides/pharmacology , Amino Acid Sequence , Bacterial Proteins/chemistry , HIV Protease/drug effects , HIV Protease Inhibitors/chemistry , Mass Spectrometry , Models, Biological , Models, Molecular , Oligopeptides/chemistry , Protein Binding , Protein Conformation/drug effects , Protein Structure, Secondary , Sequence Analysis, Protein
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