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C Caro

Publications and source records attributed to C Caro.

11 recordsLinked to original sources
PubMed2004

Repression of the human immunodeficiency virus type-1 long terminal repeat by the c-Myc oncoprotein.

The effect of trans-acting factors on cis-acting DNA elements on the HIV-1 promoter are the principal determinant regulating transcriptional activation and repression. Host factors that limit viral replication can contribute to the emergence and maintenance of proviral reservoirs. The current paradigm is that this sub-population of latently infected cells confers a biological advantage to the virus by facilitating evasion of immunologic responses and therapeutic strategies resulting in life-long and persistent infection. In this report, we show that ectopic expression of the nuclear phosphoprotein, c-Myc can inhibit HIV-1 gene expression and virus production in CD4+ T-lymphocytes. The effect exerted does not appear to involve other known functions of c-Myc such as proliferation, or apoptosis. The mechanism does implicate c-Myc in a direct role. We have found evidence that c-Myc can specifically recognize the HIV-1 initiator element surrounding the start site of transcription and linker scanning mutagenesis experiments confirmed a loss of c-Myc-mediated repression in the absence of this region. Moreover, we show that c-Myc can interact with the initiator binding proteins YY-1 and LBP-1 and can cooperate with these factors to synergistically repress HIV-1 LTR transcription. Taken together, these results indicate that c-Myc is an important regulator of HIV-1 transcription that potentially contributes to the latent proviral state.

Apoptosis↗
PubMed2003

Survival of Campylobacter jejuni strains of different origin in drinking water.

AIMS: The aim of the study was to measure the survival of 19 Campylobacter jejuni strains of different origins, including two reference strains, four poultry-derived isolates, nine human isolates and four water isolates, in sterilized drinking water. METHODS AND RESULTS: Pure cultures of 19 C. jejuni strains were inoculated in sterile drinking water and incubated at 4 degrees C for 64 days. Survival was determined by culturability on both selective (Karmali agar) and non-selective [Columbia blood agar (CBA)] media. Culturability was shown to be strain and origin-dependent. Campylobacter jejuni showed prolonged survival on a non-selective than on a selective medium. CONCLUSIONS: The origin of the strain is a determining factor for the survival of C. jejuni in drinking water at 4 degrees C. Poultry isolates showed a prolonged survival, which could be an indication that these strains could play an important role in the transmission of campylobacteriosis through water. In addition, culture conditions are an important factor for evaluating the survival of C. jejuni in drinking water at 4 degrees C. The non-selective agar (CBA) allowed growth of C. jejuni over a longer period of time than the selective agar (Karmali). Furthermore, an enrichment broth (Bolton) allowed the recovery of all 19 C. jejuni strains during the 64 days of incubation at 4 degrees C. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlighted differences in culturability depending on culture conditions and on strain origin.

Animals↗
PubMed1998

Sugar transport and glut transporter expression in a variety of human immunodeficiency virus-1 (HIV-1) chronically infected target cell lines.

In this study, sugar transport and the cellular content of the human Glut 1 and 3 glucose transporters were ascertained in uninfected and chronically HIV-infected Jurkat and H9 cell lines (T-cell lines) and U937 cells (a promonocytic cell line). Sugar transport was determined by monitoring 2-deoxy glucose uptake (2DG) and glut transporter content was determined by Western analysis. Although 'acute' HIV infection of H9 cells led to increased cellular transport activity and Glut 3 transporter content, chronic HIV infection exhibited no significant differences in sugar transport in any of the cell types investigated whether log or stationary phase cultures were employed. When uninfected and chronically HIV-infected cell lines were compared, all cell lines expressed the Glut 1 transporter, however, significant differences in Glut 1 transporter content were not observed. The Glut 3 transporter which could only be detected in the H9 cell line exhibited no differences in Glut 3 content in uninfected or chronically HIV-infected cells (2.1 +/- 0.6 versus 3.8 +/- 2.1 x 10(-3) arbitrary units/microgram protein). A trend towards lower amino acid uptake was seen in the chronically HIV-infected cells but this was not significantly different from uninfected cell cultures. The data indicate that: (1) glucose transport and the Glut 1 and 3 transporters are not increased in cells chronically infected with HIV-1 and (2) the expression of the Glut 3 sugar transporters is not the same in all target cells.

Biological Transport, Active↗
PubMed1994

Noninvasive determination of local wavespeed and distensibility of the femoral artery by comb-excited Fourier velocity-encoded magnetic resonance imaging: measurements on athletic and nonathletic human subjects.

The local distensibility of arteries is of interest because distensibility varies from artery to artery, may be altered by disease to different extents in different arteries, and may be modified by physiological or pharmacological means. Using magnetic resonance imaging (MRI) we have measured local arterial wavespeed in the femoral artery in healthy human subjects and calculated local arterial distensibility. We acquired 2-D coronal and sagittal MR phase contrast angiograms of the femoral artery. We used a novel imaging technique, comb-excited Fourier velocity-encoded MRI, to obtain simultaneous measurements of arterial blood velocity at two stations 14 cm apart on the femoral artery. The separation of the two stations divided by the delay between the onset of forward flow at the two stations was used to calculate the wavespeed. The measurements were made on 16 healthy men (8 athletes, 8 non-athletes) in the age range 20-30 years, who were scanned with the use of ECG gating and an extremity coil in a 1.5 Tesla scanner (GE Medical Systems, Milwaukee, WI). By systematically altering the delay between the R-wave and data acquisition, a temporal resolution of 2-4 ms was achieved. The onset of forward flow at each station was determined from a least-squares fit to the data for 30% of the maximum velocity during the cardiac cycle. Average femoral artery wavespeed was 7.7 m/s +/- 1.2 in the athletes and 11.5 m/s +/- 1.1 in the non-athletes (P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Phonological transformations in Spanish-speaking aphasics.

Thirty-seven aphasic patients whose native language is Spanish were divided into four groups: (1) Broca's, (2) Wernicke's, (3) Conduction, and (4) Anomia. Phonological errors produced on repetition and object-naming tasks were analyzed in terms of type of transformation and degree of similarity between target and errors in terms of shared distinctive features. Segmental transformations were of the following types: (1) pure substitution, (2) pure addition, (3) deletion, (4) reduplicative addition (doublet creation)--anticipatory (right to left) or preservative (left to right), (5) reduplicative substitution (doublet creation)--anticipatory or perseverative, and (6) mutual exchanges. Pure substitutions were the most prevalent, exchanges, the least. Some error types were found to differentiate significantly between aphasic populations. We suggest that different mechanisms may underlie the same error type for different aphasic populations.

Adult↗
PubMed1989

Pregnancy results following embryo transfer in women receiving low-dosage variable-length estrogen replacement therapy for premature ovarian failure.

This study was undertaken to evaluate the effectiveness of a new, constant low-dose, variable-length estrogen replacement therapy in preparing the endometrium of women suffering premature ovarian failure for embryo implantation. Five of 10 patients receiving the new regime became pregnant following a total of 14 embryo transfers. This study proves the efficacy of low-dosage variable-length estrogen replacement therapy for preparing the endometrium for embryo implantation in patients suffering premature ovarian failure. These studies confirm earlier observations that sequentially increasing doses of estrogen during the follicular phase are unnecessary for implantation and that the length of the follicular phase within certain undefined limits is not critical. A second important observation arising from this study concerns the relative effectiveness of the route of administration of progesterone. Five of seven patients became pregnant after receiving vaginal pessaries, compared to none of seven following intramuscular injections.

Adult↗
PubMed1989

Oocyte donation: a review.

Oocyte donation provides an option for achieving pregnancy in women lacking functioning gonads, or in whom IVF techniques have failed to harvest adequate oocytes, or those who do not wish to use their own gametes because of hereditary disease. In agonadal women, artificial menstrual cycles are required before proceeding to gamete donation. A fixed cyclical steroid replacement schedule of oestradiol (E2) valerate and progesterone (P4) pessaries was initially used, but the need for synchrony between donor and recipient cycles, and the narrow window for implantation limited the transfer of fresh embryos. Donor-recipient cycle asynchrony can be overcome by using frozen-thawed embryos, or by extending the follicular phase in the recipient to widen the transfer window. Twenty-two pregnancies have now been achieved by the Monash/Epworth group, resulting in the birth of 13 healthy infants. There were no statistically significant differences in pregnancy rates (per transfer) between transfers in natural cycles (14%, four pregnancies) and steroid replacement cycles (24%, 16 pregnancies). Five pregnancies (36%) were established in women treated with 2 mg of E2 daily 13-18 days before embryo transfer with P4 starting on the day of or the day following oocyte retrieval. E2 was continued for a median of 85 days (range 49-110) and P4 for a median of 86 days (range 49-133) after the supposed last menstrual period. All but one delivery was by caesarean section. There were no perinatal deaths and no ectopic pregnancies.

Embryo Transfer↗
PubMed1987

A controlled study between the use of gamete intrafallopian transfer (GIFT) and in vitro fertilization and embryo transfer in the management of idiopathic and male infertility.

A randomized controlled trial comparing the use-effectiveness between gamete intrafallopian transfer (GIFT) and in vitro fertilization (IVF) and embryo transfer (ET) procedures showed no significant difference in pregnancy rates in the management of patients presenting with idiopathic or male infertility. The cost-effectiveness of GIFT appears superior to IVF and ET with laparoscopic oocyte collection, but comparable to IVF-ET with ultrasonic oocyte collection. The lack of data on the fertilizing capacity of sperm in GIFT procedures in cases of male infertility is a real disadvantage and currently precludes the management of severe male infertility with this method.

Adult↗
PubMed1986

The search for donor eggs: a problem of supply and demand.

Although seven babies who were conceived in vitro with donated oocytes have been born in the Monash-Epworth programme, the availability of this service is now threatened because of the scarcity of oocytes for donation. Previously oocytes were donated by infertile women undergoing oocyte collection in the in vitro fertilisation programme, but this supply has been severely curtailed since cryopreservation of their embryos has been made available to them. Other sources of donated oocytes have included collecting oocytes from women undergoing laparoscopic sterilization, infertile women finding their own (known) donors, and fertile women donating all their oocytes for altruistic reasons on an in vitro fertilisation programme. The latter two categories offer the greatest chance of collecting mature oocytes for donation.

Female↗
PubMed1980

[Dissecting aneurysm of the aorta presenting as acute pericarditis (author's transl)].

Two cases of leakage of an aortic dissecting aneurysm into the pericardial cavity presenting as acute pericarditis are reported. In both cases the existence of risk factors (hypertension and coarctation of the aorta) suggested the correct diagnosis. Echocardiography showed enlargement of the ascending aorta and thickening of vascular wall in the two cases, furthermore it suggested the presence of aortic insufficiency in one case. The definite diagnosis was made by means of aortography. One patient died after surgery, while the other was successfully treated with hypotensive drugs. Dissecting aneurysm of the aorta may present atypical clinical manifestations; in these circumstances a great suspicion index is the basis for a correct diagnosis. The importance of an early diagnosis by means of aortography and echocardiography is emphasized.

Acute Disease↗