Perifolliculitis capitis abscedens et suffodiens.
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Biomedical subjects
Publications and source records attributed to A Herman.
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The staphylococcal enterotoxin A (SEA) is a superantigen that must bind to class II molecules of the major histocompatibility complex to be recognized by T cells. In humans, most HLA-DR class II allelic and isotypic forms, such as DR1, bind SEA well. DRw53 is an exception, binding SEA very poorly. We have localized this difference to a single residue (amino acid 81) in the beta 1 domain. A highly conserved histidine at residue 81 allows SEA binding, but a tyrosine does not. Residue 81 is predicted to lie in an alpha-helix on the surface of the molecule, with its side chain pointing up out of the pocket associated with binding of conventional peptide antigens. This finding supports the hypothesis that superantigens and conventional antigens bind to different sites on the class II molecule.
Thirty patients with clear ovarian cysts underwent aspiration guided by vaginal ultrasound. In 23 cases a complete aspiration was accomplished. In 4 only partial aspiration was possible, and in the remaining 3 failed aspiration led to surgery. Histological findings correspond to retroperitoneal lipoma and mucinous cystadenoma (2 cases). Malignant cells were not detected in the fluid of any of the 27 aspirates. Eight of the ten patients presenting with abdominal pain experienced a relief following aspiration. Recurrence of the cyst occurred in 12 cases (40%) with significantly smaller dimensions (P less than 0.01). Vaginal ultrasound aspiration of clear cyst is easy and safe and can be considered as an outpatient procedure.
A retrospective study in two university hospitals investigating retinal changes in pregnancies complicated by hypertension, seldom revealed retinal vascular changes in pre-eclamptic toxemia. Fluorescein angiography was performed on 16 severe pre-eclamptic toxemias and 14 chronic hypertension pregnancies. Normal caliber retinal vessels and normal filling time, with no subretinal or subepithelium leakage, was found in all pre-eclamptic toxemic patients. Four out of the 14 chronic hypertensive patients showed signs of mild hypertensive retinopathy. A review of the literature on fluorescein angiography in pregnancy showed that vascular changes in pre-eclamptic toxemia are choroidal rather than retinal.
Extremely large number of twists of the umbilical cord causing torsion of the entire length of the umbilical cord was found in two cases of intrauterine fetal death. It was twisted in one case 35 times and in the other 20 times. No additional pathology, such as stricture or abnormality of the Wharton's jelly, was found. The two mothers complained of decreased fetal movements and both newborns were found later to be growth retarded. A long cord of 120 cm was present in one case and normal length of 70 cm in the other. Close antenatal care in cases with growth retarded fetuses or decreased fetal movements may help in avoiding fetal demise in such rare cases.
Delayed fertilization is common in cycles with immature oocytes. This phenomenon was observed in 42 of 423 with mature oocytes. Of the 42 cycles, 16 were excluded because of the presence of sperm autoantibodies. Sperm parameters of the remaining 26 (6.1%) cycles (group A) were compared with those in cycles with no fertilization at all (group B) and those in the control group (group C). The percentage of normal forms was 15% in group B and 24% in group A compared with 51% in group C. Fertilization rates were 32% in group A compared with 81% in group C. The incidence of poor embryonic morphology was 82% in group A compared with 29% in group C. Delayed fertilization and poor embryonic morphology associated with impaired sperm quality is of clinical and prognostic importance.
Ectopic pregnancy remains one of the undesired sequelae of in-vitro fertilization (IVF) treatment. It seems that mechanical infertility increases the risk of this complication in IVF. Thus, the surgeon treating such a case faces the dilemma of the optimal surgical procedure because of the increased risk for repeated ectopic pregnancy in subsequent IVF cycles. Two cases are presented with repeated ectopic pregnancy occurring in IVF. One case underwent salpingectomy on the first occasion and eventually developed a contralateral repeat ectopic gestation ending with salpingectomy. The second case underwent a conservative salpingotomy in the first event and developed a repeated ectopic gestation on the same side, undergoing bilateral salpingectomy. In order to prevent repeated ectopic pregnancies in an IVF programme, a definitive surgical procedure, such as bilateral salpingectomy, should be considered in the first episode in patients referred for IVF because of tubal pathology.
Superantigens combine with MHC class-II molecules to form the ligands that stimulate T cells via the V beta element of the T-cell receptor. Two groups of superantigens have been described so far: first, endogenous murine products that include the Mls determinants, and second, bacterial products such as the Staphylococcal enterotoxins. Here, we review studies that address the interactions between the foreign superantigens and MHC class-II molecules, the mechanism of T-cell stimulation, and the role that tolerance to self-superantigens plays in shaping the T-cell repertoire. We speculate on the possible evolutionary significance of superantigens.
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A prospective study was designed to compare cycles stimulated by human menopausal gonadotropin (hMG) (group A) with cycles pretreated with gonadotropin-releasing hormone agonist causing pituitary desensitization followed by hMG stimulation (group B). Three hundred two cycles were randomly allocated to each group. Cancellation rate was 27.2% in group A compared with only 3.3% in group B. Significantly less hMG ampules for a shorter period were needed in group A patients. Lower estradiol and higher luteinizing hormone levels were detected in the hMG group. Patients in group B yielded significantly more oocytes and more embryos per retrieval. A significantly higher pregnancy rate per cycle was obtained in group B (27%) as compared with that of group A (13%). Moderate and severe ovarian hyperstimulation syndrome was significantly more frequent in group B than in group A.
Functional nocturnal enuresis is a common problem which causes a great deal of stress to the suffering children and their families. Some chiropractors advocate chiropractic care as a mode of therapy for this complaint. One hundred and seventy-one enuretic children, aged 4 to 15, were treated with chiropractic adjustments, and their number of wet nights was monitored by their parents. The median number of wet nights per week was 7.0 at the onset of the study. After 2 wk without any therapy, the number of wet nights had decreased to 5.6 (p = .01) and by the end of the treatment this figure was 4.0 (p less than .0001). Following the course of treatment, 15.5% of subjects wet a maximum of 2 nights per fortnight, or, where data for the last 2 wk of therapy were unavailable, a maximum of 1 night/wk. This result is less favorable than the therapeutic success of other common types of therapy, which have reported "cure" rates well above 50%. The only variable which predicted treatment outcome was the initial estimate of bed-wetting; the more severe the condition at the onset, the less likely was the child to improve by the end of the study. In the absence of a control group there appears to be no validity in the claim that chiropractic is a treatment of choice for functional nocturnal enuresis.
Staphylococcal enterotoxins (SEs) have been shown to bind to major histocompatibility complex (MHC) class II proteins and stimulate T cells in a V beta-specific manner, and these V beta specificities for various SEs have been well documented in mice and humans. This study was undertaken in order to examine the ability of human class II molecules to present SEs to human and murine T cell hybridomas. Using a panel of transfectants expressing individual HLA class II antigens, we have shown that HLA-DR alleles differ in their ability to bind and present SEs. Since the HLA-DR proteins share a common alpha chain, these results indicate that the polymorphic beta chain plays an important role in SE binding and presentation to T cells. In addition, we have shown that human class II isotypes markedly differ in their ability to present SEs. The results of this study should provide information on the region of MHC class II molecules that interacts with foreign, and perhaps self, super-antigens.
The alpha beta T-cell antigen receptor (TCR) recognizes antigenic peptides in the context of self major histocompatibility complex (MHC) molecules. The specificity of recognition of MHC plus antigen is generally determined by a combination of the variable elements of alpha- and beta-chains of the TCR. Several types of antigen, however, have been identified that, when bound to MHC molecules, stimulate T cells bearing particular variable-region beta-chain (V beta) elements irrespective of the other variable components of the TCR. These have been termed 'superantigens', and here we are concerned with one type of superantigen, the toxins produced by Staphylococcus aureus. T cells have been found that bear closely related members of the same V beta family but respond differently to S. aureus toxins; in particular, cells bearing the human V beta 13.2 element respond to toxin SEC2, whereas cells bearing human V beta 13.1 do not. We have now defined the residues of the V beta element responsible for this difference, and find that they reside in a region thought to lie on the side of the TCR molecule, away from the conventional antigen/MHC-binding site. The evolutionary conservation of this site may be due to its having an important role in some function of the TCR other than the binding of conventional antigen plus MHC.
The Staphylococcus aureus enterotoxins are known to be potent T cell activators, stimulating cell proliferation and lymphokine production. Two additional S. aureus proteins, exfoliating toxin and toxic shock syndrome toxin, share these properties. Recently these molecules have been termed "super-antigens" because of their ability to bind to class II MHC molecules and thus form ligands that interact with TCR in an unconventional manner. In this paper we show that each toxin stimulates mouse T cells bearing receptors that include particular V beta regions, almost regardless of the other variable receptor components. In addition, different toxins have different specificities for V beta.
A case of intrapartum fetal death in which the maternal heart rate was recorded by internal fetal monitoring is presented. The electrical activity of the maternal heart was transmitted via the fetal body and the recording mimicked a "normal" fetal heart rate (FHR). The patient was referred because of sudden abdominal pain and bleeding; Doppler fetal heart tones were not heard. Because internal monitoring was synchronous with the maternal pulse, ultrasonography was performed and established the diagnosis of fetal demise. Awareness and usage of simple modalities are mandatory for proper diagnosis in such cases.
The value of luteal phase supplementation with human chorionic gonadotropin (hCG) was assessed after a combined protocol of ovarian stimulation, using a long acting gonadotropin releasing hormone analog (GnRH-a) and human menopausal gonadotropins (hMG), in a randomized prospective study of 36 consecutive cycles in an in vitro fertilization (IVF) program. The patients were allocated on the transfer day to either luteal phase supplementation with hCG (Group A, n = 18) or none (Group B, n = 18). Nine patients of Group A conceived as compared with 3 in Group B. Five patients, all in Group A, developed ovarian hyperstimulation syndrome (OHSS) (3 moderate and 2 severe forms). Analysis of the hormonal profiles disclosed similar progesterone (P), estradiol (E2), and E2/P ratio up to the 6th post ovum pick-up day. Then, E2 and mainly P levels decreased only in Group B resulting in a rising E2/P ratio. These findings stress the importance of luteal support in IVF cycles treated with GnRH-a. In light of the increased risk of OHSS among hCG treated patients, further studies are needed to assess the optimal preparation needed.
To study the effect of mycoplasmas and Chlamydia trachomatis infection on semen quality, these microorganisms were cultured from the semen and anterior urethra respectively, in a group of 175 infertile men suspected of a silent genital infection with a poor postcoital test. Chlamydia infection, but not mycoplasmas, was parodoxically more frequent in the apparently normal than oligotetratoasthenozoospermia patients. Mycoplasmas male infection, but not chlamydia, was more frequent in cases with female, mechanical, and/or organic infertility factors. Infection was unrelated to the accessory gland evaluation or sperm variables. However, seminal antisperm antibody activity was significantly increased in cases with any positive culture. By this local antibody increase, chlamydia and mycoplasmas may significantly reduce sperm egg penetration ability.
The incidence of GnRH-analog administration in the presence of undiagnosed pregnancy is discussed. Immediate hormonal supplementation avoids luteolysis. The report includes two cases, one without hormonal replacement, in which preclinical pregnancy occurred, and the second, where P was supplemented immediately upon diagnosis of pregnancy.