PubMed Health⌕ Search

Biomedical subjects

M Matta

Publications and source records attributed to M Matta.

At least 19 recordsLinked to original sources
PubMed2001

Cervicovaginal secretory antibodies to human immunodeficiency virus type 1 (HIV-1) that block viral transcytosis through tight epithelial barriers in highly exposed HIV-1-seronegative African women.

Antibodies to human immunodeficiency virus (HIV) of the IgA, IgG, and IgM isotypes and high levels of the HIV suppressive beta-chemokine RANTES (regulated on activation, normally T cell expressed and secreted) were found in the cervicovaginal secretions (CVSs) of 7.5% of 342 multiply and repeatedly exposed African HIV-seronegative female sex workers. The antibodies are part of a local compartmentalized secretory immune response to HIV, since they are present in vaginal fluids that are free of contaminating semen. Cervicovaginal antibodies showed a reproducible pattern of reactivity restricted to gp160 and p24. Locally produced anti-env antibodies exhibit reactivity toward the neutralizing ELDKWA epitope of gp41. Study results show that antibodies purified from CVSs block the transcytosis of cell-associated HIV through a tight epithelial monolayer in vitro. These findings suggest that genital resistance to HIV may involve HIV-specific cervicovaginal antibody responses in a minority of highly exposed HIV-seronegative women in association with other protecting factors, such as local production of HIV-suppressive chemokines.

Adolescent↗
PubMed2001

Detection of Y chromosome DNA as evidence of semen in cervicovaginal secretions of sexually active women.

The detection of traces of semen in cervicovaginal secretions (CVS) from sexually active women practicing unprotected sex is a prerequisite for the accurate study of cervicovaginal immunity. Two semen markers, the prostatic-specific antigen (PSA) and the Y chromosome, were detected in parallel in CVS obtained by a standardized vaginal washing of consecutive women attending the principal medical center for sexually transmitted diseases of Bangui, Central African Republic. PSA was detected by immunoenzymatic capture assay in the cell-free fraction of CVS, and the Y chromosome was detected by a single PCR assay of DNA extracted by silica from the cell fraction (Y PCR). Fifty (19%) cell-free fractions of the 264 beta-globin-positive CVS samples were positive for PSA, and 100 (38%) cell fractions of the CVS samples were positive for the Y chromosome. All the 50 (19%) PSA-containing CVS samples were also positive for the Y chromosome. Fifty (19%) CVS samples were positive only for the Y chromosome, with no detectable PSA. The remaining 164 (62%) CVS samples were both PSA and Y chromosome negative. These findings demonstrate that CVS from sexually active women may contain cell-associated semen residues unrecognized by conventional immunoenzymatic assays used to detect semen components. The detection of cell-associated male DNA with a highly sensitive and specific procedure such as Y PCR constitutes a method of choice to detect semen traces in female genital secretions.

Adolescent↗
PubMed2000

Interactions between herpes simplex virus type 2 and human immunodeficiency virus type 1 infection in African women: opportunities for intervention.

Sexually transmitted diseases (STDs) are cofactors for human immunodeficiency virus (HIV) transmission, but the specific role of herpes simplex virus type 2 (HSV-2) is unclear. This study aimed to examine the in vivo relationships between HSV-2 and HIV-1 in 300 women in Bangui, Central African Republic. Sera were tested for syphilis, HIV-1, HSV-2 antibody, and levels of vitamins A and E. Genital specimens were tested for other STDs. HSV-2 DNA and HIV-1 RNA were quantified in cervicovaginal lavage. The prevalences of HSV-2 antibody (91% vs. 78%, P=.02), HSV-2 shedding (43% vs. 22%, P=. 003), and levels of HSV-2 DNA (P=.01) were all significantly higher among HIV-1-seropositive than among HIV-1-seronegative women. There was a significant correlation between genital HIV-1 RNA and HSV-2 DNA levels (P=.02) among the 23 women who were shedding HSV-2 DNA. If confirmed, such associations highlight the urgent need for HSV-2 control measures in populations at high risk of both infections.

Black People↗
PubMed2000

Protection of cynomolgus macaque against cervicovaginal transmission of SIVmac251 by the spermicide benzalkonium chloride.

We evaluated the potential effectiveness of a spermicide cationic surfactant, benzalkonium chloride (BZK), to prevent the transmission of simian immunodeficiency virus (SIV) after intravaginal inoculation in 12 cynomolgus macaques. The inoculation procedure involved deposition of 6.7 ivag-AID50 of cell-free SIVmac251 into the receiving vagina, four times over a 2-week period, at the end of the luteal phase of the menstrual cycle. Six randomly selected females received vaginally foam containing BZK (7.37%, wt/wt) before each inoculation (BZK group), whereas the remaining were not pretreated (control group). In controls, 5 animals presented persistent SIV infection and 1 had a transient viremia. The number of uninfected animals was higher in the BZK group (6 of 6) than in controls (0 of 6). These findings demonstrate that BZK placed in the vaginal receptacle prior to SIV inoculation provides a significant protection in vivo. The wide spectrum of antimicrobial activities of BZK (including HIV) in addition to its efficiency to block the transmucosal passage of SIV in the macaque model qualifies this drug as an attractive topical microbicide to prevent sexually transmitted infections in humans.

Animals↗
PubMed1998

The sequential occurrence of pol 215 and pol 41 zidovudine resistance mutations is associated in an additive fashion with low CD4 cell counts and high plasma and cellular HIV viral load.

We report on a cross-sectional study of virological and immunological surrogate markers of HIV infection in 115 patients for whom a determination of the pol 215 and pol 41 zidovudine (ZDV) resistance mutations had been described between January 1995 and February 1996. The patients received ZDV alone or a combination of ZDV and zalcitabine or didanosine. A total of 55, 15 and 45 patients exhibited a wild (W), a mixed (MIX) or a mutant (M) genotype at codon pol 215, respectively; 85, 10 and 20 patients exhibited a W, a MIX or a M genotype at codon pol 41, respectively. Patients exhibiting the pol 215 M genotype had lower CD4 cells, higher plasma viral load and higher proviral burden than patients exhibiting the pol 215 W genotype. Patients who had variants exhibiting both pol 215 M and pol 41 M or MIX genotypes had significantly worsened surrogate marker values than patients having variants only carrying the pol 215 M genotype. These observations demonstrate that the two mutations additively associate with pejorative surrogate markers.

Adult↗
PubMed1998

Behavior in a mouse model of isolates of Leishmania donovani sensu lato cultured from the blood of patients with chronic cutaneous lesions.

Our objective was to characterize biologically in an animal model two isolates of Leishmania parasites unexpectedly encountered in the circulating blood of two patients with chronic cutaneous leishmaniasis. Both isolates were classified by cellulose acetate electrophoresis as belonging to the L. donovani senso lato complex. We elected to use BALB/c mice, an inbred strain that has been proven to be very sensitive to the dermotropic parasite L. major. This study demonstrated that for the same number of parasites, the course of infection with the L. donovani strain was different from that developed in similar animals that received the L. major strain. After a protracted incubation period, L. donovani produced scanty cutaneous lesions and mainly a systemic disease. This is in contrast to the rapidly spreading skin lesion that kills L. major-infected animals within a few months. It is concluded that BALB/c mice are an adequate animal model for the L. donovani strain, which had an unusual clinical presentation in humans. The prolonged incubation period, such as observed here, may lead to erroneous conclusions of host resistance if the experiment were terminated based on L. major activity in the same model. Finally, the unusual behavior in humans and mice of certain strains (such as the one encountered in these patients) must reflect peculiar intrinsic features of the parasite, which are best understood using animal models in the laboratory.

Animals↗
PubMed1998

Aspirated air capnography with esophageal detector device to confirm tracheal intubation in rapid sequence induction.

Verification of the proper placement of a tracheal tube by capnography in rapid sequence induction can lead to aspiration if the patient is ventilated with the tube in the esophagus. In this study we have associated the capnography with the esophageal detector device as modified by Nunn. In 49 patients, two endotracheal tubes were introduced, one in the esophagus and the other in the trachea. An anesthesiologist, unaware of which tube is in the trachea, squeezed the bulb of the esophageal detector device, attached it to the sidestream of the capnography and the endotracheal tubes, then released it. No reinflation of the bulb was seen with the esophageal tube. Two types of reinflation were seen with the tracheal tube: slow (6 cases), all were obese, and instant (43 cases) in the remaining patients. The air aspirated from the respiratory tract by the bulb was analyzed by the capnograph; CO2 was detected from all the tracheal tubes but not from the esophageal ones. We concluded that the esophageal detector device and capnography used as described in our study is a simple reliable test to confirm the proper placement of a tracheal tube before starting ventilation in rapid sequence induction.

Adolescent↗
PubMed1997

In vivo semen-associated pH neutralization of cervicovaginal secretions.

Physiological cervicovaginal acidity can partly inactivate human immunodeficiency virus (HIV). Basic semen components should be able to partially neutralize in vivo cervicovaginal pH. The goals of the study were to evaluate the relationship between cervicovaginal pH and presence of semen components in sexually active African women and to assess whether vaginal douching with water performed just after sexual intercourse could significantly reduce semen components and restore physiological cervicovaginal pH. Cervicovaginal secretion (CVS) from 56 heterosexual African women (19 to 45 years old), living in Bangui, Central African Republic, were evaluated for pH, semen components (prostatic acid phosphatase [PAP] and prostatic specific antigen [PSA]), cellularity, and hemoglobin at inclusion and after vaginal douching with 100 ml of water by using a bock. Before douching, semen components were found in 46 of 56 CVS (82%). The mean vaginal pH was 5.2 (range, 3.6 to 7.7), and concentrations of both PAP and PSA correlated positively and strongly with cervicovaginal pH (P < 0.001). After douching, semen components were found in 35 of 56 CVS (62%) (P = 0.03). Cervicovaginal PAP and PSA levels were significantly decreased (respectively, P < 0.0001 and P < 0.01; PAP, -72%; PSA, -87%), as was the total cell count (-60%; P < 0.0001). Furthermore, in CVS previously positive for both PAP and PSA, the mean vaginal pH was significantly decreased (6.5 versus 5.3, P < 0.01); no genital bleeding was observed. Frequent persistence of semen in CVS from heterosexually active African women leads to a shift from acidity to neutrality that could favor male to female HIV transmission. Vaginal douching provides significant elimination of semen after sexual intercourse; it should be considered for study as a supplementary means for the prevention of heterosexual HIV transmission.

Acid Phosphatase↗
PubMed1997

Preanesthetic wrapping of legs for prevention of spinal induced hypotension.

Forty-four male patients undergoing herniorrhaphy under spinal anesthesia were allocated to 2 groups. Group I had 15 ml/kg of lactated ringer intravenously as prehydartion for prevention of spinal induced hypotension. Group 11 had the trendelenbourg position to 30 degrees for 2 minutes and the legs wrapped with elastic Esmarch bandage prior to spinal anesthesia without fluid prehydration. In both groups, ephedrine was used to treat spinal induced hypotension. The later was defined as a decrease in the systolic arterial pressure less than 75% of the baseline value. The incidence of hypotension was greater in the fluid prehydration group (4 of 22) as well as the mean dose of ephedrine required to treat hypotension (7 +/- 10 mg) than the group with wrapping of the legs (1 of 22 and 5 +/- 0 mg). It is concluded that trendelenbourg position and wrapping of the legs prior to the spinal block might prevent the sudden decrease in arterial blood pressure that occurs during spinal anesthesia.

Adult↗
PubMed1996

Lack of predictive value for progression of dissociated circulating P24 antigen in human immunodeficiency virus type 1-infected black patients.

In human immunodeficiency virus type 1 (HIV)-1-infected Black people, the circulating p24 antigen is hidden frequently in immune complexes, because of high titers of serum anti-p24 antibodies. In order to evaluate the prognostic values for progression of free and dissociated serum p24 antigen in Black people, sera from 45 HIV-1-infected Black patients, all at non-AIDS stages, were evaluated prospectively for p24 antigen by several assays; circulating free p24 antigen was measured by immunocapture ELISA only (method 1) and with ELAST amplification (method 2), and dissociated p24 antigen determined after glycine-HCl pretreatment of serum, by immunocapture ELISA only (method 3) and with ELAST amplification (method 4). Serum CD4 and CD8 cell counts, beta 2-microglobulin, and total IgA were determined also at least twice a year. Clinical events for AIDS were those included in the 1986 CDC classification for HIV infection. At entry, p24 antigen was found in 3 (6.7%) patients by method 1, in 7 (15.6%) by method 2, in 14 (31.1%) by method 3, and in 22 (48.9%) by method 4. Methods 3 and 4 were more sensitive than method 1 (P < 0.001) and method 2 (P < 0.001). The mean follow-up was 30 months. The free symptom survival times (mean +/- SD months) were significantly lower in patients being p24 antigen positive by method 1 [(+) 33 +/- 27 vs. (-) 61 +/- 15, P = 0.03), but they were similar in patients positive and in those negative for p24 antigen determined by method 2 [(+) 71 +/- 17 vs. (-) 74 +/- 9, P = 0.54], method 3 [(+) 76 +/- 12 vs. (-) 69 +/- 13.2, P = 0.80], and method 4 [(+) 79 +/- 9 vs. (-) 63 +/- 7, P = 0.71]. At 24 months, p24 antigen positivity did not correlate either with CD4 or CD4/CD8 slops, nor with beta 2-microglobulin or IgA variations. By contrast, a CD4 cell count below 200/mm3 at entry was significantly associated with disease progression. In conclusion, dissociated p24 antigenemia does not appear as a useful surrogate marker for progression in HIV-1-infected Black people.

Adult↗
PubMed1996

Depression of excitatory effects of propofol induction by fentanyl.

Propofol is an intravenous anesthetic drug commonly used in outpatient anesthesia for its rapid and smooth onset of action, short recovery period and its minimal perioperative side effects. However, propofol like other intravenous anesthetic drugs can produce excitatory signs during induction without signs of epilepsy on EEG. We studied 64 patients scheduled for various outpatient procedures. The patients were allocated to 2 groups: Group A (n = 32) received on induction xylocaine 1 mg.Kg-1 followed by propofol 2 mg.Kg-1 over 20 seconds, Group B (n = 32) received xylocaine 1 mg.Kg-1 and fentanyl 1.5 ug.Kg-1 followed by propofol 2 mg.Kg-1 over 20 seconds. The incidence of excitatory movements (cough, hiccup, hypertonus, twitching or tremors) was in group A (13) significantly higher than that in group B (1), there was no significant difference between the two groups in the time of stay in the post anesthesia care unit. Fentanyl 1.5 ug.Kg-1 used in outpatient anesthesia with propofol 2 mg.Kg-1 provides cardio-vascular stability, deepens the anesthesia level, decrease the awareness and decrease the excitatory effects or propofol.

Adjuvants, Anesthesia↗
PubMed1995

Detection of seminal antibodies to human immunodeficiency virus in vaginal secretions after sexual intercourse: possible means of preventing the risk of human immunodeficiency virus transmission in a rape victim.

Detection of semen anti-human immunodeficiency virus (HIV) antibodies within the cervicovaginal secretions from a non-HIV-infected woman who has had a recent sexual intercourse with an HIV-infected man is theoretically possible since the seminal fluid from all HIV-infected men contains a high titer of IgG antibodies to HIV. We report the case of an HIV-seronegative African woman whose cervico-vaginal secretions contained IgG antibodies to HIV, including antibodies to HIV-env-encoded glycoproteins. This woman had also detectable prostatic specific antigens and acid phosphatase in her cervico-vaginal secretions, establishing the persistence of semen. In order to confirm whether anti-HIV antibodies in seminal fluid could be detected in vitro when mixed with cervico-vaginal secretions, 10(-1) to 10(-6) 10-fold dilutions of seminal fluid from HIV-1-seropositive donors were realized with a pool of HIV-negative cervico-vaginal secretions as diluent. Six commercial enzyme immunoassays or rapid tests were compared for semen anti-HIV detection in the secretions. At a 10(-1) dilution of the mixture, all assays were markedly positive for all tested semens and the greatest dilutions of seminal fluid showing positivity ranged from 10(-3) to 10(-5). The IgG immunocapture assay appeared to be the most sensitive test. The rapid tests permitted the detection of semen IgG antibodies to HIV at dilutions ranging from 10(-1) to 10(-3) suggesting their potential value in emergency situations.

Coitus↗
PubMed1995

Human immunodeficiency virus type 1 p24 antigen in cervicovaginal secretions.

The failure to detect human immunodeficiency virus (HIV) antigen in cervicovaginal secretions (CVS) from HIV-infected women could be due in part to an in situ formation of immune complexes involving HIV antigens and cervicovaginal anti-HIV antibodies. CVS from 30 HIV-1-infected heterosexual women were assayed for p24 antigen detection by ELISA before and after acid disruption of immune complexes. Before acid treatment, free p24 antigen was detected in only 1 sample of CVS, whereas after acid dissociation, 4 (13.5%) of 30 samples had detectable and neutralizable p24 antigen. Adsorbent capacities of the CVS for recombinant p24 antigen, evaluated in an in vitro model, depended on both titer and avidity of cervicovaginal antibodies to HIV. In conclusion, local antibodies to HIV are able in vivo to bind HIV antigen within CVS and to participate in the immune exclusion of free virus particles or proteins.

Adolescent↗
PubMed1994

Hypertonic saline prehydration in patients undergoing transurethral resection of the prostate under spinal anaesthesia.

Thirty-three patients undergoing elective transurethral resection of the prostate were allocated randomly to receive either 0.9% isotonic saline 7 ml kg-1 (16 patients), or 3% hypertonic saline 7 ml kg-1 (17 patients) as a preload before spinal anaesthesia. After spinal anaesthesia, the incidence of systolic arterial pressure < 75% of control value was greater in the normal saline group than in the hypertonic saline group. Also, the mean dose of phenylephrine required to maintain arterial pressure > 75% of the baseline value was significantly greater in the normal saline group than in the hypertonic saline group.

Adult↗
PubMed1994

[Free dissociated and precipitated p24 antigenemia of HIV-1 in subjects of the black race].

P24/HIV-1 antigen in the sera from 41 HIV-1-infected Black individuals, living in the Central African Republic (n = 17) and in France (n = 24), and in 21 HIV-1-infected Caucasians patients, matched on the stages of the disease, has been detected and quantified by ELISA, without and with acid pretreatment of the sera by HC1 or by glycine, and after ultracentrifugation of serum. Free p24 antigenemia was detected less frequently in Black patients (9.7%), than in Caucasian controls (33%) (p < 0.05). Decomplexed p24 antigenemia was detected in 34% of patients after dissociation of circulating immune complexes (CIC) by HC1 (p < 0.01) and in 44% of patients after dissociation of CIC by glycine (p < 0.001). However, the mean concentration of decomplexed p24 antigenemia of positive sera was higher after pretreatment by HC1 (88 pg/ml) than by glycine (52 pg/ml), suggesting that a strong acid is more convenient than a weak one to disrupt the CIC in Black individuals. After ultracentrifugation of the serum, the detection of p24 antigen was not significantly increased. Acid dissociation of CIC is a usefull method to increase the sensitivity of detection of circulating p24 antigen in HIV-1-infected Black individuals.

AIDS Serodiagnosis↗