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J Cohen

Publications and source records attributed to J Cohen.

At least 847 records · Page 47Linked to original sources
PubMed1993

An epidemiological study of disorders in late childhood and adolescence--I. Age- and gender-specific prevalence.

Developmental aspects of psychiatric disorders may be inferred from patterns of age differences in prevalence. Age-specific prevalences are provided for nine disorders in a general population sample of ages 10-20. Age and gender patterns for several disorders suggest developmental stage-associated risks. These include oppositional disorder in both genders and conduct disorder and major depression in girls. Major depression shows a pattern suggestive of a role for the onset of puberty. The prevalence of one or more disorders did not differ by age or gender. However, the pattern of specific diagnoses varied greatly by both age and gender.

Adolescent↗
PubMed1993

An epidemiological study of disorders in late childhood and adolescence--II. Persistence of disorders.

The persistence and new onset of psychiatric disorder were studied in a sample of 734 children from the general population. Diagnoses for six of the more prevalent disorders were generated from maternal and child interviews when the children were ages 9-18 and again 2 1/2 years later. Analyses demonstrated substantial levels of diagnostic persistence over the 2 1/2 year period for all diagnoses except major depression. With few exceptions persistence was roughly equivalent for age and gender subgroups. It is concluded that disorders assessed by structured interview of non-clinical samples of children cannot be dismissed as transitory.

Adolescent↗
PubMed1993

In vitro effect of anticardiolipin autoantibodies upon total and pulsatile placental hCG secretion during early pregnancy.

BACKGROUND: The anticardiolipin syndrome is characterized among other features by recurrent thromboembolic events, thrombocytopenia, and recurrent fetal loss associated with high IgG titers of anticardiolipin antibodies and/or the presence of lupus anticoagulant. AIMS: The mechanisms for the fetal loss in this syndrome have not yet been clearly elucidated, although several hypothesis based on experimental data have been put forward. We wanted to evaluated the effect in vitro of anticardiolipin antibodies on the secretion of human chorionic gonadotropin. METHODS: Employing our previous experience with placental explants, we studied the effect of several mouse monoclonal and human polyclonal purified anticardiolipin antibodies (ACA), which were shown by us to induce experimental antiphospholipid syndrome (APLS), to affect the pulsatile secretion of beta human choriogonadotropin. RESULTS: The mouse monoclonal ACA antibodies caused an increase in the pulsatility of beta human choriogonadotropin, while human polyclonal ACA derived from patients with ACA had an inhibitory effect. CONCLUSIONS: These studies with placental explants show that ACA may have an additional effect on placental hormone secretion and thus affect the fate of the embryo.

Abortion, Habitual↗
PubMed1993

The alkaline protease of Aspergillus fumigatus is not a virulence determinant in two murine models of invasive pulmonary aspergillosis.

Little is known of the pathophysiology of invasive pulmonary aspergillosis (IPA), an opportunistic fungal infection usually caused by Aspergillus fumigatus. It has been suggested that the ability of the fungus to degrade elastin may aid its invasion and growth in lung tissue. We have described previously the construction of a strain of A. fumigatus in which the gene encoding an alkaline protease, AFAlp, had been disrupted (C.M. Tang, J. Cohen, and D.W. Holden, Mol. Microbiol. 6:1663-1671, 1992); this mutant is deficient in extracellular proteolytic and elastinolytic activity over a broad pH range. In this study, we compared the pathogenicity of this and another AFAlp disruptant with their isogenic, elastase-producing parental strains in two murine models of IPA. In both models, animals were inoculated via the respiratory tract. In the first model, the inoculum was delivered as airborne conidia and animals developed signs of respiratory distress within 2 to 4 days. In the second model, conidia were administered intranasally as a suspension and the disease developed over a 2-week period. No difference was observed between the wild-type and AFAlp disruptants in terms of mortality, and elastin breakdown was detected in lung tissue from animals inoculated with all four strains. We conclude that AFAlp is not a virulence determinant in these models of IPA.

Animals↗
PubMed1993

Detection of Aspergillus fumigatus by polymerase chain reaction.

Aspergillus fumigatus is an opportunistic nosocomial pathogen causing an often fatal pneumonia, invasive aspergillosis (IA), in immunosuppressed patients. Oligonucleotide primers were used to amplify a 401-bp fragment spanning the 26S/intergenic spacer region of the rDNA complex of A. fumigatus by the polymerase chain reaction (PCR). The primers were highly sensitive and specific: as little as 1 pg of A. fumigatus genomic DNA could be detected, and the primers only amplified DNA from A. fumigatus and not any other fungal, bacterial, viral, or human DNA tested. Using the PCR, we were able to detect A. fumigatus DNA in lung homogenates from immunosuppressed mice experimentally infected with A. fumigatus but not from immunosuppressed uninfected controls. There was 93% correlation between the culture results and the PCR results. In a retrospective clinical study, the sensitivity of the PCR for the detection of A. fumigatus in clinical samples was confirmed by positive amplification in three of three culture-positive respiratory samples from confirmed cases of IA. Because isolation of Aspergillus spp. may reflect contamination and colonization without infection, the feasibility of using the PCR was evaluated by analyzing culture-negative samples from both immunosuppressed patients at high risk for IA and immunocompetent patients with other lung infections. Only 2 of 10 patients were culture negative and PCR positive in the high-risk group, and 2 of 7 patients were culture negative and PCR positive in the immunocompetent group. The results indicate that PCR detection might be a valuable adjunct to current laboratory methods to diagnose IA.

Adult↗
PubMed1993

Rotavirus protein NSP3 (NS34) is bound to the 3' end consensus sequence of viral mRNAs in infected cells.

Interaction between viral proteins and RNAs has been studied in rotavirus-infected cells. The use of UV cross-linking followed by immunoprecipitation and labeling with T4 polynucleotide kinase allowed us to detect interactions between RNA and nonstructural viral proteins. The RNAs linked to the nonstructural protein NSP3 have been identified as rotavirus mRNAs, and the sequences of the RNase T1-protected fragments have been established. These sequences correspond to the 3' end sequence common to all rotavirus group A genes. We also show that the last 3' nucleotide is cross-linked to the protein and that monomeric and multimeric forms of NSP3 are bound to rotavirus mRNA. The role of NSP3 in rotavirus replication is discussed in the light of our results and by comparison with other RNA-binding proteins of members of the Reoviridae family.

Base Sequence↗
PubMed1993

Pathogenic serum IgG anticardiolipin antibodies and the idiotypic network.

OBJECTIVES: To determine whether active immunisation of mice with pathogenic anticardiolipin antibodies (IgG and IgM), derived from the serum of a patient with the antiphospholipid syndrome, could dysregulate the idiotypic cascade and induce the production of anti-anti-anti-cardiolipin (Ab3) with anticardiolipin activity by the mice with the association of overt antiphospholipid syndrome. METHODS: Anticardiolipin antibodies were purified from the serum of a patient with the antiphospholipid syndrome. The purified anticardiolipin antibodies were used to immunise mice at the footpads and the mice were then followed up for serological and clinical manifestations of the antiphospholipid syndrome. RESULTS: The IgG anticardiolipin antibody was found to be monospecific and to bind cardiolipin with high affinity. Immunisation of naive BALB/c mice with the purified IgG anticardiolipin antibody was followed by production in the mice of sustained high titres of IgG anticardiolipin antibody, associated with a prolonged activated partial thromboplastin time (64.5 (9.7) v 30.1 (1.7) seconds in control mice) and thrombocytopenia (0.4 (0.06) x 10(9) v 1.0 (0.09) x 10(9)/l platelets in controls). The titres of other autoantibodies (for example, antibodies to DNA, histone), though high after the immunisation, decreased rapidly and were almost undetected one month after the boost injection. The mice immunised with the IgG anticardiolipin antibody showed low fecundity (36% of mice became pregnant v 62% in the group immunised with control IgG). The pregnant mice had an increased resorption rate (the equivalent of fetal loss in the human) of 61 (9)% v 5 (4)% in the control group. The mean (SD) embryo and placental weights in mice with the antiphospholipid syndrome were significantly lower than in the mice injected with control IgG (641 (210) and 103 (14) mg v 1303 (105) and 145 (8) mg respectively. The IgM anticardiolipin antibodies purified from the same patient were found to be polyspecific, binding with low affinity to anticardiolipin antibodies and double stranded DNA, and carried the anti-DNA idiotype 16/6. Mice immunised with the purified IgM anticardiolipin antibodies, though showing reduced fecundity (30%), had only a slightly increased resorption rate (12 (9) v 3 (5)% in controls) and only a slight and statistically non-significant decrease in mean (SD) embryo and placental weights (1134 (188) and 136 (11) mg respectively). CONCLUSIONS: The results confirm the induction of pathogenic anticardiolipin antibodies by immunisation with serum anticardiolipin, dysregulating the idiotypic network, and point to the higher pathogenic potential of serum IgG v IgM anticardiolipin antibodies.

Adult↗
PubMed1993

Assessment of the human splanchnic venous volume-pressure relation using radionuclide plethysmography. Effect of nitroglycerin.

BACKGROUND: No method exists to assess human splanchnic venous function, the most important region in terms of vascular capacity. METHODS AND RESULTS: We studied 25 stable patients without heart failure or hypertension to develop a method to assess the splanchnic venous volume-pressure (V-P) relation and to determine the effect of nitroglycerin (GTN). We used blood pool scintigraphy to assess changes in regional splanchnic vascular volume (SVV) and low levels of continuous positive airway pressure (CPAP) to passively alter venous pressure and thus, SVV. We postulated that the relation between SVV and the CPAP used would reflect the capacitance of the splanchnic venous bed and that changes in the position of this relation would provide a relative measurement of any change in capacitance. In 12 patients (group 1), the splanchnic vascular V-P curves were recorded before and 2, 9, and 20 minutes after 0.6 mg sublingual GTN; in eight patients (group 2), recordings were made at similar times before and after sublingual administration of placebo; in five patients (group 3), the hemodynamic effects of CPAP were assessed by means of right and left cardiac catheterization. Right atrial and femoral venous pressures increased (p < 0.001) and cardiac output fell (p < 0.05) during CPAP. There was an apparently linear relation between CPAP and SVV (r = 0.74-0.98); SVV increased an average of 7.4 +/- 2.2% (p < 0.001) by 12 cm H2O CPAP: The splanchnic vascular V-P curves were reproducible with minimal variability in SVV (+/- 2%, p > 0.2) in group 2. After administration of GTN, the splanchnic vascular V-P curve shifted away from the pressure axis in a parallel fashion by an average of 9.4 +/- 5.4% (p < 0.001). CONCLUSIONS: We have developed a reproducible noninvasive technique that may be used to assess human splanchnic venous V-P relations. We have demonstrated for the first time in humans that GTN exerts its dilatory effect by increasing the unstressed splanchnic venous volume.

Erythrocytes↗
PubMed1993

The detection of Aspergillus spp. by the polymerase chain reaction and its evaluation in bronchoalveolar lavage fluid.

Invasive pulmonary aspergillosis (IPA) is an important cause of mortality and morbidity in the immunocompromised host. However, the diagnosis of this condition may be difficult, and it is sometimes missed because of the lack of sensitivity of available tests. Therefore, we used polymerase chain reaction (PCR)-based amplification of fragments of genes-encoding alkaline proteases from Aspergillus fumigatus and A. flavus to detect these organisms in bronchoalveolar lavage fluid specimens. The predicted size of the product (747 base pairs) after amplification of A. fumigatus was larger than that for A. flavus (690 base pairs). The reaction was highly sensitive (after amplification of 500 fg of A. fumigatus DNA, product could be detected by Southern analysis), and it was specific for A. fumigatus and A. flavus. Bronchoalveolar lavage fluid from four immunosuppressed patients with proved or probable IPA was positive by this assay (sensitivity, 100%); in addition, the sample from one patient with possible IPA was PCR-positive. Only one specimen from 18 immunosuppressed patients with no evidence of IPA was PCR-positive (specificity, 94.4%). Five of 28 bronchoalveolar lavage samples from nonimmunosuppressed patients were PCR-positive, probably representing colonization of the respiratory tract. PCR-based detection may prove useful in the diagnosis of IPA.

Adult↗
PubMed1993

Implementation of the Boys Town psychoeducational treatment model in a children's psychiatric hospital.

OBJECTIVE: The study assessed the effect of the Boys Town psychoeducational treatment model on the therapeutic milieu of a state-operated psychiatric hospital serving children and adolescents. METHODS: Direct care staff from two units for adolescents and one unit for children were trained to implement the model, which guides staff in planned and spontaneous interactions with patients. Patients rated their satisfaction with direct care staff immediately before the model was implemented and one year later. Staff perceptions of changes in the treatment environment were assessed by retrospective interviews. RESULTS: Patients in two of the three units indicated significantly greater satisfaction with direct care staff after the psychoeducational treatment model was implemented. Results from retrospective interviews with staff showed statistically significant improvements in their perceptions of the therapeutic milieu. Staff comments recorded during the interviews supported the quantitative results. CONCLUSIONS: Training direct care staff at a children's psychiatric hospital to use the Boys Town psychoeducational treatment model significantly improved perceptions of the therapeutic milieu among both staff and patients.

Adolescent↗
PubMed1993

Detection of anti-phospholipid and anti-DNA antibodies and their idiotypes in newborns of mothers with anti-phospholipid syndrome and SLE.

The titers, isotypes and idiotypes of antiphospholipid and anti-dsDNA antibodies were determined in seven pairs of mothers with antiphospholipid syndrome (APLS) and their offspring, in 11 pairs of SLE mothers and their matched infants and in seven respective pairs of healthy subjects. In addition, maternal as well as fetal sera were evaluated for the presence of anti-SSA (Ro), anti-SSB (La) and anti-70 kd RNP autoantibodies. In the sera from APLS patients, as well as in the sera from their offspring, the mean antibody titer of IgG aCL was found to be significantly higher then the corresponding value in the control group (P < 0.01). Highly significant increased titers of IgG anti-DNA antibodies were found in the sera of SLE mothers and their matched offspring (P < 0.0008). The prevalence of anti-SSA, anti-SSA, and anti-70Kd RNP antibodies was lower then that of antiphospholipid and anti-dsDNA antibodies. Only one of the respective offspring had increased levels of these antibodies. The quantity of maternal antibodies transferred to the fetus was depended on their concentration in the maternal circulation, as well as on their type and specificity. Follow-up of newborn sera showed a progressive decrease in the antiphospholipid antibody titers during 3 months. After 6 months it was undetected. Our results point to a transplacental transfer of aCL and anti-DNA antibodies, a phenomenon which is not necessarily associated with respective clinical manifestations, in contrast to the classical humoral mediated autoimmune diseases (e.g. myasthenia gravis).

Adult↗
PubMed1993

[Estrogen-progestin contraception. Advantages of estrogen reduction].

Among the low dose oral contraceptives that is to say less than 50 mcg of ethinylestradiol per pill one must single out the pills made of a third generation progestagen (desogestrel, gestodene, norgestimate) from the others. The contraceptive efficacy (tested on the Pearl index) according to the files of government authorities visa (AMM) is equivalent for all the oral contraceptives whatever their composition (between 0 to 0.07 women year). The clinical tolerance of the low dose pills of the 3rd generation is comparable to that of the other low dose pills. Is there any advantage then in prescribing them? The most important advantage is the decrease of metabolic and vascular effects. The use of so-called third generation progestive, besides the beneficial effects an lipidic and glucidic metabolisms, has mainly enabled the decrease of the estrogen doses of progestagens. The ethinylestradiol is directly implicated in the risk of venous thrombosis: hemostasis the modifications are less important with 30 mcg than with 50, 20 than 30 mcg. Relying on theoretical arguments one could have estimated that minipills would lead to an insufficient ovarian slow down. These hypothesis are contradicted by recent studies from Falsetti and Benagiano who studied the rates of FSH and LH under minipills. This does not include the variability and the individual sensitiveness of the patients and as well the reason following which minipills would favor functional ovarian cysts, lies on the confusion made between a cyst and a 20 mm diameter follicule.(ABSTRACT TRUNCATED AT 250 WORDS)

Breast Neoplasms↗
PubMed1993

Improved ECG models for estimation of left ventricular hypertrophy progression and regression incidence by redefinition of the criteria for a significant change in left ventricular hypertrophy status. The MRFIT Research Group. Multiple Risk Factor Intervention Trial.

Three sets of left ventricular hypertrophy (LVH) criteria were evaluated in terms of their utility for LVH progression and regression incidence estimation. Incidence comparisons were performed with and without taking short-term variability into consideration using electrocardiographic records taken at the baseline and the first annual follow-up examination of 11,969 men, aged 37 to 55 years, at the baseline of the Multiple Risk Factor Intervention Trial. Short-term total technical and biologic variability (95% range) was determined from the records of 104 men invited for a repeat electrocardiographic recording at 2-week or shorter intervals from the first recording. The results indicated that after elimination of the false fraction due to normal variability, the residual incidence estimates are so low that their utility and statistical power in monitoring changes in LVH status is very limited. It is concluded that a redefinition of LVH progression and regression criteria is needed to enhance their utility in clinical trials.

Adult↗
PubMed1993

Assisted hatching facilitates earlier implantation.

OBJECTIVE: To examine whether opening of the zona pellucida (i.e., assisted hatching) accelerates implantation. DESIGN: In a controlled, randomized trial, patients were assigned to control and assisted hatching groups. SETTING: All patients studied were of the Center for Reproductive Medicine at Cornell University Medical College. INTERVENTION: All patients underwent stimulation with gonadotropins after luteal phase GnRH down regulation. Assisted hatching with zona drilling using acidic Tyrode's solution was performed on the assigned embryos. MAIN OUTCOME MEASURES: Luteal E2, P, and hCG on days +5, +6, +7, +8, +9, +11, +13, and +15 were measured. The implantation time, peak midluteal E2 and intervals between these two values were studied. RESULTS: Implantation occurred significantly earlier in the assisted hatching group. The interval between implantation and peak midluteal E2 was also significantly shorter in the assisted hatching group than in the controls. However, there was no significant difference in the day of the peak midluteal E2 between the assisted hatching and control groups. CONCLUSION: Assisted hatching may enhance embryo implantation not only by mechanically facilitating the hatching process but also by allowing earlier embryo-endometrium contact. Such early contact may enhance embryonic development potential and may optimize synchronization between embryo and endometrium, resulting in improved implantation efficiency.

Chorionic Gonadotropin↗
PubMed1993

Evidence of increased nitric oxide production in patients with the sepsis syndrome.

To investigate whether the hypotension of septic shock is due to an excess production of nitric oxide (NO), we have determined the serum levels of nitrate and nitrite (NO3/NO2), the stable end-products of NO, in 12 patients with the sepsis syndrome and marked hypotension. Compared to a mean NO3/NO2 level of 36.4 microM in controls (n = 7), the group of septic patients had a significantly elevated mean NO3/NO2 level of 124 microM (P < 0.01, Wilcoxon two-sample test). A lesser elevation was also seen in a group of postoperative patients (mean level 87.3 microM, n = 7), which was significantly elevated compared to controls (P < 0.01, Wilcoxon two-sample test), but was not significantly lower than the septic group (0.1 > P > 0.05, Wilcoxon two-sample test). These data suggest that NO may be responsible, at least in part, for the hypotension of septic shock.

Adult↗