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1.
Cryo Letters ; 41(4): 194-201, 2020.
Article in English | MEDLINE | ID: mdl-33988647

ABSTRACT

BACKGROUND: Superoxide dismutase (SOD) as an antioxidant in semen extender may be used for the cryopreservation of buffalo spermatozoa and in vivo fertility. OBJECTIVE: This study was aimed to evaluate the effects of SOD (SOD1, 100 IU/mL; SOD2, 200 IU/mL; SOD3, 300 IU/mL) and control (0.0) in Tris citric acid extender on in vitro quality and in vivo fertility of cryopreserved water buffalo bull spermatozoa. MATERIALS AND METHODS: Semen collection was carried out on a weekly basis (four bulls, three replicates, and n = 24 ejaculates). The conventional freezing of semen loaded straws (0.5 mL) was undertaken by placing them horizontally on a steel rack inside a Styrofoam box for 10 min containing liquid nitrogen (LN2) vapours, and plunging into a liquid nitrogen tank (-196 °C) for storage, followed by thawing at 37 °C for 30 s and analysis by computer-assisted sperm analyzer (CASA) and other assays. RESULTS: At post-dilution, the acrosome integrity (ACR-I, %) was significantly improved (P < 0.05) in extender supplemented with SOD3 as compared to other experimental groups. In addition, DNA integrity (DNA-I, %) was significantly higher (P < 0.05) in SOD1 and SOD3 compared to SOD2 and control. At post-thawing, the mean values of sperm progressive motility (PM, %), average path velocity (VAP, µm/s) and straight line velocity (VSL, µm/s) were significantly higher (P < 0.05) in extender supplemented with SOD3 compared to the control. At post-thawing, mean values of subjective motility (SM, %), plasma membrane integrity (PMI, %) and ACR-I were significantly higher (P < 0.05) in extender supplemented with SOD3 compared to the control. At post-thawing, sperm DNA-I was significantly higher (P < 0.05) in extender supplemented with all SOD doses compared to the control in a dose-dependent manner. The in vivo fertility rate (%) was significantly higher with SOD3 compared to the control (68.2 % vs. 49.5 %). CONCLUSION: The supplementation of SOD3 (300 IU/mL) in Tris citric acid extender improves both in vitro quality and in vivo fertility of buffalo bull spermatozoa.


Subject(s)
Cryopreservation , Cryoprotective Agents , Semen Preservation , Superoxide Dismutase/pharmacology , Animals , Buffaloes , Cryopreservation/veterinary , Cryoprotective Agents/pharmacology , Fertility , Male , Semen Analysis , Semen Preservation/veterinary , Sperm Motility , Spermatozoa
2.
Transbound Emerg Dis ; 60(1): 9-16, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22280210

ABSTRACT

Prevalence, distribution and antibiotic resistance of Arcobacter spp. were investigated in cattle, goats, floor and treated water samples in this study. The prevalence of Arcobacter in adult and young was recorded as 8/110 (7.27%) and 4/83 (4.81%), respectively, which showed insignificant difference (P = 0.3503) in detection rates between adult and young cattle. A total of 33.33% of the floor samples and 11.11% of the treated water samples analysed were determined as positive for Arcobacter. Among the species isolated, over all, A. butzleri (45%) was the most frequently detected species, followed by A. skirrowii (5%). A. butzleri was isolated from adult cattle, floor and water samples at the rates of 75.0%, 33.4% and 50%, respectively. Co-colonization of species was not uncommon, and 50% of the samples were carrying more than one Arcobacter species. Only 12.5% sample from cattle (adult) was detected positive for only A. skirrowii. All samples from young animals, floor and water contained mixed isolates. None of the samples from goat farm was found to be carrying Arcobacter species. On profiling of antimicrobial resistance patterns, it was found that only one A. butzleri isolate (3.7%) was sensitive to all nine antibiotics tested. A. butzleri was found highly resistant to ampicillin (55.6%), followed by cefotaxime (33.4%) and ciprofloxacin (33.4%). Overall, 20% of the isolates showed multidrug resistance (resistant ≥4 antibiotics). Gentamicin and enrofloxacin can be used as drugs of choice for the treatment for Arcobacter infections.


Subject(s)
Anti-Bacterial Agents/pharmacology , Arcobacter/isolation & purification , Drug Resistance, Bacterial , Gram-Negative Bacterial Infections/veterinary , Water Microbiology , Animals , Arcobacter/drug effects , Arcobacter/genetics , Cattle , Goats , Gram-Negative Bacterial Infections/drug therapy , Gram-Negative Bacterial Infections/epidemiology , Housing, Animal , Malaysia/epidemiology , Polymerase Chain Reaction , Prevalence
4.
J Food Prot ; 75(8): 1474-8, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22856572

ABSTRACT

A total of 106 beef samples which consisted of local (n = 59) and imported (n = 47) beef and 180 milk samples from cows (n = 86) and goats (n = 94) were collected from Selangor, Malaysia. Overall, 30.2% (32 of 106) of beef samples were found positive for Arcobacter species. Imported beef was significantly more contaminated (46.80%) than local beef (16.9%). Arcobacter butzleri was the species isolated most frequently from imported (81.8%) and local (60%) beef, followed by Arcobacter cryaerophilus in local (33.3%) and imported (18.2%) beef samples. Only one local beef sample (10%) yielded Arcobacter skirrowii. Arcobacter species were detected from cow's milk (5.8%), with A. butzleri as the dominant species (60%), followed by A. cryaerophilus (40%), whereas none of the goat's milk samples were found positive for Arcobacter. This is the first report of the detection of Arcobacter in milk and beef in Malaysia.


Subject(s)
Arcobacter/isolation & purification , Food Contamination/analysis , Meat/microbiology , Milk/microbiology , Animals , Cattle , Colony Count, Microbial , Consumer Product Safety , Food Microbiology , Goats , Humans , Malaysia , Prevalence , Species Specificity
5.
Vet Microbiol ; 160(3-4): 355-61, 2012 Dec 07.
Article in English | MEDLINE | ID: mdl-22739058

ABSTRACT

Arcobacter is getting more attention due to its detection from wide host-range and foods of animal origin. The objective of this study was to determine the prevalence of Arcobacter spp. in various sources at farm level and beef retailed in markets in Malaysia and to assess the genetic relatedness among them. A total of 273 samples from dairy cattle including cattle (n=120), floor (n=30), water (n=18) and milk (n=105) as well as 148 beef samples collected from retail markets were studied. The overall prevalence of Arcobacter in various sources was 15% (63/421). However, source-wise detection rate of Arcobacter spp. was recorded as 26.66% (8/30) in floor, 26.3% (39/148) in beef, 11.11% (2/18) in water, 7.6% (8/105) in milk and 6.66% (8/120) in cattle. Arcobacter butzleri was the frequently isolated species however, a total of 75%, 66.7%, 53.8%, 50% and 12.5%% samples from floor, milk, beef, water and cattle, respectively, were carrying more than one species simultaneously. One (12.5%) cattle and beef sample (2.5%) found to be carrying one Arcobacter spp., A. skirrowii, only. Typing of Arcobacter isolates was done though pulsed field gel electrophoresis (PFGE) after digested with Eag1 restriction endonuclease (RE). Digestion of genomic DNA of Arcobacter from various sources yielded 12 major clusters (≥ 50% similarity) which included 29 different band patterns. A number of closely related A. butzleri isolates were found from beef samples which indicate cross contamination of common type of Arcobacter. Fecal shedding of Arcobacter by healthy animals can contaminate water and milk which may act as source of infection in humans.


Subject(s)
Arcobacter/genetics , Environmental Microbiology , Food Microbiology , Animals , Arcobacter/classification , Cattle , Genetic Variation , Genotype , Meat/microbiology , Milk/microbiology , Phenotype , Phylogeny
6.
J Appl Microbiol ; 110(6): 1571-83, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21447014

ABSTRACT

AIMS: Research into the relationship between pathogens, faecal indicator microbes and environmental factors in beach sand has been limited, yet vital to the understanding of the microbial relationship between sand and the water column and to the improvement of criteria for better human health protection at beaches. The objectives of this study were to evaluate the presence and distribution of pathogens in various zones of beach sand (subtidal, intertidal and supratidal) and to assess their relationship with environmental parameters and indicator microbes at a non-point source subtropical marine beach. METHODS AND RESULTS: In this exploratory study in subtropical Miami (Florida, USA), beach sand samples were collected and analysed over the course of 6 days for several pathogens, microbial source tracking markers and indicator microbes. An inverse correlation between moisture content and most indicator microbes was found. Significant associations were identified between some indicator microbes and pathogens (such as nematode larvae and yeasts in the genus Candida), which are from classes of microbes that are rarely evaluated in the context of recreational beach use. CONCLUSIONS: Results indicate that indicator microbes may predict the presence of some of the pathogens, in particular helminthes, yeasts and the bacterial pathogen Staphylococcus aureus including methicillin-resistant forms. Indicator microbes may thus be useful for monitoring beach sand and water quality at non-point source beaches. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of both indicator microbes and pathogens in beach sand provides one possible explanation for human health effects reported at non-point sources beaches.


Subject(s)
Bacteria/isolation & purification , Bathing Beaches , Environmental Monitoring/methods , Helminths/isolation & purification , Water Microbiology , Yeasts/isolation & purification , Animals , Colony Count, Microbial , Florida , Seawater/microbiology , Seawater/parasitology , Silicon Dioxide/analysis
7.
Saudi J Biol Sci ; 17(1): 1-4, 2010 Jan.
Article in English | MEDLINE | ID: mdl-23961051

ABSTRACT

The objective of the current study was to determine the incidence of common types of parasites encountered in the Central Region of Saudi Arabia. The current study is a retrospective study which includes the results of 10427 stool sample and occult blood sample. The results obtained during last two years (2005-2007), were compared to the earlier reports on parasites in the Central as well as other regions of Saudi Arabia. Attempts were made to find out the cases of increasing and/or decreasing trend of parasite incidence and to locate any differences between the current study results and the earlier reports.

8.
Amino Acids ; 36(1): 91-8, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18264660

ABSTRACT

To evaluate the response of soybean to salt stress, the related changes in protein expression were investigated using the proteomic approach. Soybean plants were exposed to 0, 50, 100, and 200 mM NaCl. Especially at 200 mM, the length and fresh weight of the hypocotyl and root reduced under salt stress, while the proline content increased. Proteins from the hypocotyl and root treated with 100 mM NaCl were extracted and separated by two-dimensional polyacrylamide gel electrophoresis; 321 protein spots were detected. In response to salt stress, seven proteins were reproducibly found to be up- or down-regulated by two to sevenfold: late embryogenesis-abundant protein, beta-conglycinin, elicitor peptide three precursor, and basic/helix-loop-helix protein were up-regulated, while protease inhibitor, lectin, and stem 31-kDa glycoprotein precursor were down-regulated. These results indicate that salinity can change the expression level of some special proteins in the hypocotyl and root of soybean that may in turn play a role in the adaptation to saline conditions.


Subject(s)
Glycine max/drug effects , Glycine max/metabolism , Hypocotyl/metabolism , Plant Roots/metabolism , Proteome/analysis , Sodium Chloride/pharmacology , Stress, Physiological/drug effects , Amino Acid Sequence , Hypocotyl/drug effects , Hypocotyl/growth & development , Plant Proteins/analysis , Plant Proteins/chemistry , Plant Roots/drug effects , Plant Roots/growth & development , Proteome/chemistry , Glycine max/growth & development
9.
Surg Endosc ; 20(3): 504-10, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16437266

ABSTRACT

OBJECTIVE: The rotational angle of the laparoscopic image relative to the true horizon has an unknown influence on performance in laparoscopic procedures. This study evaluates the effect of increasing rotational angle on surgical performance. METHODS: Surgical residents (group 1) (n = 6) and attending surgeons (group 2) (n = 4) were tested on two laparoscopic skills. The tasks consisted of passing a suture through an aperture, and laparoscopic knot tying. These tasks were assessed at 15 degrees intervals between 0 degrees and 90 degrees , on three consecutive repetitions. The participant's performance was evaluated based on the time required to complete the tasks and number of errors incurred. RESULTS: There was an increasing deterioration in suturing performance as the degree of image rotation was increased. Participants showed a statistically significant 20-120% progressive increase in time to completion of the tasks (p = 0.004), with error rates increasing from 10% to 30% (p = 0.04) as the angle increased from 0 degrees to 90 degrees. Knot-tying performance similarly showed a decrease in performance that was evident in the less experienced surgeons (p = 0.02) but with no obvious effect on the advanced laparoscopic surgeons. CONCLUSIONS: When evaluated independently and as a group, both novice and experienced laparoscopic surgeons showed significant prolongation to completion of suturing tasks with increased errors as the rotational angle increased. The knot-tying task shows that experienced surgeons may be able to overcome rotational effects to some extent. This is consistent with results from cognitive neuroscience research evaluating the processing of directional information in spatial motor tasks. It appears that these tasks utilize the time-consuming processes of mental rotation and memory scanning. Optimal performance during laparoscopic procedures requires that the rotation of the camera, and thus the image, be kept to a minimum to maintain a stable horizon. New technology that corrects the rotational angle may benefit the surgeon, decrease operating time, and help to prevent adverse outcomes.


Subject(s)
Clinical Competence , Laparoscopy , Suture Techniques , Task Performance and Analysis , General Surgery/education , Humans , Internship and Residency , Medical Staff, Hospital , Rotation
10.
Public Health ; 118(4): 292-8, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15121438

ABSTRACT

The use of kohl (surma) as eyeliner is a popular practice in Saudi Arabia and people firmly believe that it is safe to use. A total of 107 kohl samples (branded and unbranded) were collected from different regions of Saudi Arabia, and analysed for the presence of lead. In addition, aluminium and antimony levels were also determined. Lead levels up to 53% were detected in some kohl preparations, and some samples were found to contain camphor and menthol. The blood analyses of regular kohl users revealed a high lead concentration and relatively low haemoglobin levels. Due to the health risk, an official public awareness campaign is suggested to encourage the use of lead-free kohl.


Subject(s)
Cosmetics/toxicity , Eye , Aluminum/analysis , Aluminum/blood , Antimony/analysis , Antimony/blood , Cosmetics/chemistry , Humans , Lead/analysis , Lead/blood , Saudi Arabia
11.
J Acoust Soc Am ; 112(5 Pt 1): 1766-79, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12430791

ABSTRACT

Guided waves in a layered elastic plate of rectangular cross section (finite width and thickness) has been studied in this paper. A semianalytical finite element method in which the deformation of the cross section is modeled by two-dimensional finite elements and analytical representation of propagating waves along the length of the plate has been used. The method is applicable to arbitrary number of layers and general anisotropic material properties of each layer, and is similar to the stiffness method used earlier to study guided waves in a laminated composite plate of infinite width. Numerical results showing the effect of varying the width of the plate on the dispersion of guided waves are presented and are compared with those for an infinite plate. In addition, effect of thin anisotropic coating or interface layers on the guided waves is investigated.


Subject(s)
Elasticity , Models, Theoretical , Ultrasonics , Time Factors
12.
Am J Med ; 111(4): 280-4, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11566458

ABSTRACT

BACKGROUND: Therapeutic endoscopy has provided a new means of treating bleeding peptic ulcers. Additional medical therapy may enhance the therapeutic benefit. Hemostasis is highly pH dependent and is severely impaired at low pH. Proton pump inhibitors, by achieving a significantly higher inhibition of gastric acidity, may improve the therapeutic outcomes after endoscopic treatment of ulcers. PATIENT AND METHODS: We enrolled 166 patients with hemorrhage from duodenal, gastric, or stomal ulcers and signs of recent hemorrhage, as confirmed by endoscopy. Twenty-six patients had ulcers with an arterial spurt, 41 patients had active ooze, 37 had a visible vessel, and 62 patients had an adherent clot. All patients received endoscopic injection sclerotherapy using 1:10,000 adrenaline and 1% polidocanol and were randomly assigned to receive omeprazole (40 mg orally) every 12 hours for 5 days or an identical-looking placebo. The outcome measures used were recurrent bleeding, surgery, blood transfusion, and hospital stay. RESULTS: Six (7%) of 82 patients in the omeprazole group had recurrent bleeding, as compared with 18 (21%) in the placebo group (P = 0.02). Two patients in the omeprazole group and 7 patients in the placebo group needed surgery to control their bleeding (P = 0.17). One patient in the omeprazole group and 2 patients in the placebo group died (P = 0.98). Twenty-nine patients (35%) in the omeprazole group and 61 patients (73%) in the placebo group received blood transfusions (P <0.001). The average hospital stay was 4.6 +/- 1.1 days in the omeprazole group and 6.0 +/- 0.7 days in the placebo group (P <0.001). CONCLUSION: The addition of oral omeprazole to combination injection sclerotherapy decreases the rate of recurrent bleeding, reduces the need for surgery and transfusion, and shortens the hospital stay for patients with stigmata of recent hemorrhage.


Subject(s)
Anti-Ulcer Agents/therapeutic use , Duodenal Ulcer/complications , Omeprazole/therapeutic use , Peptic Ulcer Hemorrhage/drug therapy , Sclerotherapy/methods , Stomach Ulcer/complications , Chi-Square Distribution , Drug Therapy, Combination , Endoscopy, Gastrointestinal , Female , Hemostasis, Endoscopic , Humans , Male , Middle Aged , Recurrence , Treatment Outcome
13.
J Ethnopharmacol ; 76(2): 151-4, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11390128

ABSTRACT

Acute (24 h) and chronic (90 days) oral toxicity studies on Commiphora molmol (oleo-gum-resin) were carried out in mice. Dosages in acute study were 0.5, 1.0 and 3 g/kg, while in chronic study dosage was 100 mg/kg per day. All external morphological, biochemical and haematological changes, in addition to body and vital organ weights were recorded. There was no significant difference in mortality in acute or chronic treatment as compared to controls. At the end of the treatment, weight gain in the treated as well as control group was significant. There was a significant increase in weight of testes, caudae epididymides and seminal vesicles in C. molmol treated group. Biochemical studies revealed no differences in C. molmol treated animals, however, haematological studies revealed a significant increase in RBC and haemoglobin levels as compared to the control group. C. molmol failed to show any spermatotoxic effects.


Subject(s)
Liver/drug effects , Plant Extracts/toxicity , Animals , Body Weight/drug effects , Dose-Response Relationship, Drug , Female , Genitalia, Male/drug effects , Liver/enzymology , Male , Mice , Organ Size/drug effects , Plant Extracts/analysis , Resins, Plant/analysis
14.
Indian J Med Sci ; 55(11): 604-8, 2001 Nov.
Article in English | MEDLINE | ID: mdl-12508633

ABSTRACT

Meditation is a mental exercise to improve mental faculty. Present attempt was to evaluate effect of Saral Meditation on development of intelligence, academic performance & cardiopulmonary functions. Results show significant improvement in development of intelligence and academic performance. There was apparent improvement in confidence and they were free from anxiety. There were also considerable changes in psychomotor ability and cardiopulmonary functions however, result was not significant.


Subject(s)
Hemodynamics , Intelligence , Meditation , Psychomotor Performance , Respiratory Mechanics , Humans
15.
Prostate ; 45(2): 167-72, 2000 Oct 01.
Article in English | MEDLINE | ID: mdl-11027416

ABSTRACT

Many malignant cells secrete transforming growth factor-beta (TGF-beta), a potent immunosuppresant, suggesting that TGF-beta production may represent a significant tumor escape mechanism from host immunosurveillance. Establishment of a leukocyte subpopulation with disrupted TGF-beta signaling in the tumor-bearing host offers a potential means for immunotherapy of cancer. Downregulation of TGF-beta secretion in tumor cells results in restoration of immunogenicity in the host, while T-cell insensitivity to TGF-beta results in accelerated differentiation and autoimmunity, elements of which may be required in order to combat self-antigen-expressing tumors in a tolerized host. The rationale, approaches, and potential pitfalls of this strategy will be discussed.


Subject(s)
Neoplasms/immunology , Neoplasms/therapy , Transforming Growth Factor beta/immunology , Animals , Autoimmunity/immunology , Genetic Therapy/methods , Humans , Immune Tolerance/immunology , Immunotherapy , Transforming Growth Factor beta/physiology
16.
World J Surg ; 23(11): 1191-4, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10501884

ABSTRACT

The prevalence, symptomatology, and outcome of Ascaris-induced liver abscess was studied prospectively in Kashmir, India, which is an endemic area of ascariasis, from December 1987 to December 1997. Of 510 patients with liver abscess admitted during this period, 74 had biliary ascariasis as the cause (14.51%). Of these 74 patients, 11 had intact ascaridae (live or dead) within the abscess. Six patients had a single abscess, and five had multiple abscesses. Seven patients had associated worms in the bile ducts. Ultrasonography was the main diagnostic procedure used. Ten patients were diagnosed based on clinical and ultrasound findings, and one was diagnosed during laparotomy. Most of the patients were young (age range 3-40 years) with a mean age of 17.20 years. Seven were females, and four were males. Ten patients underwent surgery; nine recovered completely, and one died postoperatively due to septicemia. Another patient died as well: a young child who presented late, was in refractory septic shock following suppurative cholangitis and liver abscess, and could not be taken for surgery. The mortality thus was 9.9%. Liver abscess following invasion of intrahepatic biliary radicles by ascaridae through the ampulla is an unusual complication of an otherwise common disease in Kashmir Valley, affecting children and young adults. The outcome depends on early diagnosis and surgical drainage of the abscess with extraction of worms from the ducts.


Subject(s)
Ascariasis/epidemiology , Liver Abscess/parasitology , Adolescent , Adult , Age Factors , Ampulla of Vater/parasitology , Ascariasis/physiopathology , Ascariasis/surgery , Bile Duct Diseases/epidemiology , Bile Duct Diseases/parasitology , Bile Duct Diseases/physiopathology , Bile Duct Diseases/surgery , Bile Ducts, Intrahepatic/parasitology , Cause of Death , Child , Child, Preschool , Cholangitis/parasitology , Endemic Diseases , Female , Humans , India/epidemiology , Liver Abscess/epidemiology , Liver Abscess/physiopathology , Liver Abscess/surgery , Male , Prevalence , Prospective Studies , Sex Factors , Shock, Septic/parasitology , Survival Rate , Treatment Outcome
17.
EMBO J ; 18(14): 3924-33, 1999 Jul 15.
Article in English | MEDLINE | ID: mdl-10406797

ABSTRACT

Salmonella enterica requires a type III secretion system, designated Spi/Ssa, to survive and proliferate within macrophages. The Spi/Ssa system is encoded within the SPI-2 pathogenicity island and appears to function intracellularly. Here, we establish that the SPI-2-encoded SpiC protein is exported by the Spi/Ssa type III secretion system into the host cell cytosol where it interferes with intracellular trafficking. In J774 macrophages, wild-type Salmonella inhibited fusion of Salmonella-containing phagosomes with lysosomes and endosomes, and interfered with trafficking of vesicles devoid of the microorganism. These inhibitory activities required living Salmonella and a functional spiC gene. Purified SpiC protein inhibited endosome-endosome fusion in vitro. A Sindbis virus expressing the SpiC protein interfered with normal trafficking of the transferrin receptor in vivo. A spiC mutant was attenuated for virulence, suggesting that the ability to interfere with intracellular trafficking is essential for Salmonella pathogenesis.


Subject(s)
Bacterial Proteins/metabolism , Macrophages/cytology , Salmonella enterica/pathogenicity , Amino Acid Sequence , Animals , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Biological Transport , Cell Line , Cell Survival , Cytosol/metabolism , Endosomes/metabolism , GTP-Binding Proteins/genetics , GTP-Binding Proteins/metabolism , Genes, Bacterial/genetics , Genes, Bacterial/physiology , Inhibitory Concentration 50 , Lethal Dose 50 , Lysosomes/metabolism , Macrophages/metabolism , Macrophages/microbiology , Membrane Fusion , Mice , Molecular Sequence Data , Mutation , Phagosomes/metabolism , Receptors, Transferrin/metabolism , Salmonella enterica/genetics , Salmonella enterica/metabolism , Virulence , rab5 GTP-Binding Proteins
18.
Prostate ; 39(4): 285-90, 1999 Jun 01.
Article in English | MEDLINE | ID: mdl-10344218

ABSTRACT

BACKGROUND: The present review summarizes the cellular action of TGF-beta in benign and malignant growth of the prostate. METHODS: TGF-beta is a pleiotropic growth factor. It plays an important role in the regulation of growth and differentiation in many cells. In benign prostatic epithelia, its action is mediated through a paracrine mechanism. It inhibits proliferation and induces apoptosis in prostatic epithelia. It provides a mechanism to maintain epithelial homeostasis in the prostate. In prostatic stroma, its continual action leads to smooth muscle differentiation. This effect of TGF-beta may regulate the development of prostatic smooth muscle nodules in benign prostatic hyperplasia. RESULTS: As prostatic epithelial cells undergo malignant transformation, two major events occur regarding TGF-beta action. These include the loss of expression of functional TGF-beta receptors and overproduction of TGF-beta in malignant cells. The loss of expression of functional TGF-beta receptors provides a growth advantage to cancer cells over their benign counterparts. The overproduction of TGF-beta by cancer cells has a multitude of adverse consequences. TGF-beta can promote extracellular matrix production, induce angiogenesis, and inhibit host immune function. The biological consequence of these activities is an enhanced tumorigenicity in prostate cancer. Results of our recent studies with a rat prostate cancer model suggest that the immunosuppressive effect of TGF-beta seems to be the primary cause of tumor progression. This is because, if these cancer cells were engineered to reduce the production of TGF-beta, tumor growth was inhibited in syngeneic hosts but not in immune compromised hosts. CONCLUSIONS: Our future research should take advantage of this knowledge to devise therapeutic strategies aimed at eradicating prostate cancer.


Subject(s)
Prostatic Hyperplasia/metabolism , Prostatic Neoplasms/metabolism , Transforming Growth Factor beta/metabolism , Androgens/metabolism , Animals , Gene Expression Regulation, Neoplastic , Humans , Male , Prognosis , Prostatic Hyperplasia/pathology , Prostatic Neoplasms/pathology , Up-Regulation
19.
J Biol Chem ; 274(9): 5797-809, 1999 Feb 26.
Article in English | MEDLINE | ID: mdl-10026202

ABSTRACT

Salmonella typhimurium exhibits a distinct tropism for mouse enterocytes that is linked to their expression of type 1 fimbriae. The distinct binding traits of Salmonella type 1 fimbriae is also reflected in their binding to selected mannosylated proteins and in their ability to promote secondary bacterial aggregation on enterocyte surfaces. The determinant of binding in Salmonella type 1 fimbriae is a 35-kDa structurally distinct fimbrial subunit, FimHS, because inactivation of fimHS abolished binding activity in the resulting mutant without any apparent effect on fimbrial expression. Surprisingly, when expressed in the absence of other fimbrial components and as a translational fusion protein with MalE, FimHS failed to demonstrate any specific binding tropism and bound equally to all cells and mannosylated proteins tested. To determine if the binding specificity of Salmonella type 1 fimbriae was determined by the fimbrial shaft that is intimately associated with FimHS, we replaced the amino-terminal half of FimHS with the corresponding sequence from Escherichia coli FimH (FimHE) that contains the receptor binding domain of FimHE. The resulting hybrid fimbriae bearing FimHES on a Salmonella fimbrial shaft exhibited binding traits that resembled that of Salmonella rather than E. coli fimbriae. Apparently, the quaternary constraints imposed by the fimbrial shaft on the adhesin determine the distinct binding traits of S. typhimurium type 1 fimbriae.


Subject(s)
Adhesins, Escherichia coli , Fimbriae Proteins , Fimbriae, Bacterial/physiology , Intestines/microbiology , Salmonella typhimurium/physiology , Tropism , Adhesins, Bacterial/chemistry , Adhesins, Bacterial/genetics , Adhesins, Bacterial/physiology , Amino Acid Sequence , Animals , Bacterial Adhesion , Base Sequence , Cell Line , DNA Primers , Intestines/cytology , Intestines/ultrastructure , Mice , Microscopy, Electron/methods , Molecular Sequence Data , Mutagenesis, Site-Directed , Protein Biosynthesis , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Sequence Homology, Amino Acid , Urothelium/cytology , Urothelium/microbiology
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