Thoraco-omphalopagus twins: different perinatal circumstances,different outcome

Two pairs of omphalopagus twins were encountered at the Polish Mother''s Health Institution in Lodz, Poland during the past 15 years. In the first set the prenatal diagnosis was not established and the delivery of the twins in a regional hospital was a complete surprise. Both babies died. In the second case the conjoined twins were diagnosed prenatally, surgical separation was successful, and both twins survived. The prenatal identification of conjoined twins is of cardinal importance for the planning of delivery and possible separation.     

骨水泥不同时相负载抗生素

背景：在人工关节置换中,骨水泥与何种抗生素配伍能起到有效预防和治疗置换后感染目前还存在争议。 目的：观察抗生素骨水泥中不同抗生素及不同混合方法对动物体内抗生素释放特性以及骨水泥力学性能的影响。 方法：36只大白兔随机抽签法分为6组,3个实验组在骨水泥固相与液相混合后分别加入2 g硫酸庆大霉素、1 g万古霉素、1.5 g头孢呋辛钠,制成负载抗生素的骨水泥,置于实验兔体内。3个对照组分别在40 g骨水泥固相与液相混合前加入2 g硫酸庆大霉素粉剂、1 g万古霉素粉剂、1.5 g头孢呋辛钠。 结果与结论：3种抗生素在兔体内持续平均释放时间均在31 d以上,骨水泥固相与液相混合后加入抗生素的3组抗生素洗提总量分别高于混合前加入抗生素的3组(P < 0.05),混合后加入万古霉素组的洗提总量高于其他各组(P < 0.05)。各组抗生素骨水泥的力学性能均优于ISO 5833国际标准,组间差异无显著性意义。提示抗生素能有效从骨水泥中释放,骨水泥中加入1.0~2.0 g抗生素不影响骨水泥的机械强度;万古霉素的洗提效果较好;骨水泥固相与液相混合后加入抗生素的混合方法更有利于抗生素的释出。     

Do different ischemic brain lesions have different hemorheological profiles?

Summary The following hemorheological parameters were determined in 68 patients with ischemic brain lesions and in 28 controls: yield shear stress, erythrocyte aggregation, erythrocyte rigidity, plasma viscosity, and hematocrit. The patients were classified into various groups on the basis of etiological criteria. The results revealed differences between certain hemorheological variables (erythrocyte aggregation, plasma viscosity) in some of the stroke groups. Plasma viscosity was significantly higher in patients with Binswanger's disease and significantly lower in the control group compared with values measured in patients with macroangiopathy and microangiopathy. Erythrocyte aggregation was significantly lower in the controls than in the other groups. Discriminant analysis revealed that plasma viscosity, erythrocyte aggregation and hematocrit were the most useful variables for classification.Abbreviations BMDP Biomedical Computer Programs — Series P Dedicated to Professor Dr. K. Poeck on the occasion of his 60th birthday     

Spermatogenic ability is different among males in different Y chromosome lineage

It is a controversial question whether sperm concentrations in humans are changing. Several researchers have reported on environmental factors affecting sperm quality, but the influence of genetic factors is still not fully understood. In this study, we examined the relationship between Y chromosome haplotypes and sperm concen-tration in fertile males. In addition, we determined the haplotypes of azoospermic patients. The results show that the mean sperm concentration correlates with Y chromosome type. Moreover, the occurrence of azoospermia is related to one particular Y chromosome lineage. Thus, males with a certain haplotype are at a disadvantage for fathering children. The difference of spermatogenic ability among men is important not only in pursuing male competition as in the past but also as relates to the future of modern human males. Received: May 28, 1999 / Accepted: May 29, 1999     

Use of different prostaglandin analogues for terminating pregnancy at different terms

The abortifacient effect has been compared of 15 me-PGF2 alpha, ONO 802 and 16 phenoxy-w-17,18,19,20-tetranor PGE2 given intra-muscularly, intravaginally and with or without laminaria dilatation of the cervix. Locally administered, 15 me-PGF2 alpha, proved to be more efficient than ONO 802. Laminaria had a beneficial effect on dilatation. Intramuscular administration involved the necessity of frequent injections and gastrointestinal side effects. A total of 143 patients participated in the study.     

T cells specific for different antigens express different HLA-D region products

T cell lines and clones were analyzed for surface expression of Ia antigens using monoclonal antibodies (mAb) that detect monomorphic and polymorphic epitopes on Ia molecules encoded by the HLA-DR and HLA-DQ gene clusters. All mAb bound to B lymphocytes or lymphoblastoid cell lines of the same individuals from whom the T cells were derived. Three mAb detecting monomorphic epitopes, primarily associated with HLA-DR, bound to all T cells showing that each clone or line expressed some type of Ia. Three other mAb defining polymorphic epitopes associated with HLA-DR products showed differential binding patterns. Two reagents, R3 and E15/4 recognizing the supertypic specificity DRw52 (formerly MT2), bound to every alloreactive clone, whereas the 16.23 mAb, detecting a private DR3-associated epitope, failed to bind to any clone. In contrast, the 16.23 epitope was detected on high percentages of T cells specific for purified protein derivative of tuberculin (PPD) or tetanus toxoid (TT). Biochemical studies showed that the 16.23 and DRw52-like epitopes can be present on distinct DR molecules on B cell lines and this may also be the case for T cells. Three other mAb, detecting epitopes associated with HLA-DQ, also revealed differential binding patterns when tested on various T cells. Two failed to bind to any alloreactive clone and to only low numbers of PPD- or TT-specific T cell lines, whereas the third bound distinctly to a CD4+/CD8+ alloreactive clone. Biochemical analyses have shown that these DQ epitopes can be present on different molecules. Combined, these observations indicate that differential expression of Ia molecules encoded by both HLA-DR and DQ occurs between B and activated T cells as well as among T cell populations of the same individual. Whether these differences reflect quantitative variations in expression of given DR or DQ molecules or, alternatively, are due to differential class II gene expression in activated T cells remains to be determined.     

Molecular biological comparison of different Besnoitia species and stages from different countries

Besnoitia besnoiti tissue cysts from a recent outbreak in cattle in Germany were characterized with respect to their internal transcribed spacer regions 1, 2, and 18S rDNA gene sequences. These results were compared with own sequences of an Israelian isolate of B. besnoiti and of Besnoitia jellisoni cystozoites stored for years in liquid nitrogen. Furthermore, material was studied that was obtained from white mice (Balb/C) that had been successfully infected by intraperitoneal infection of fresh cystozoites from the German outbreak. All results were then compared and discussed with respect to databank sequences of other Besnoitia species. Comprehensive phylogenetic studies of B. besnoiti isolates from Germany revealed almost identical sequence alignments when compared to previously sequenced B. besnoiti isolates from Israel and Spain. More importantly, phylogenetic analysis revealed two distant clusters of Besnoitia species: the first one includes Besnoitia akodoni, Besnoitia darlingi, and Besnoitia oryctofelisi, while the second cluster includes B. besnoiti, Besnoitia bennetti, Besnoitia tarandi, and the Besnoitia species of rodents (B. jellisoni). The also B. jellisoni named species of the GenBank (AF 076860) must be another one, since our strain derives directly from Frenkel. These findings give strong hints that B. besnoiti has a cycle between rodents and a predator and that cattle and other are only accidental hosts.     

B cells in SLE: different biological drugs for different pathogenic mechanisms

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease characterized by a complex multi-factorial pathogenesis and a great clinical polymorphism. SLE is considered to be a B cell disease in which autoantibodies are the major players. Recently, the central role of B cells has been confirmed and it has been shown that that the relative frequency of B cells subsets is altered in SLE patients. Conventional immunosuppressive therapies such as azathioprine, cyclophosphamide or methotrexate, reduce disease activity and improves the patient's general health conditions. These treatments have possible side effects; in fact they could compromise liver function, fertility and innate and adaptive immune responses. Moreover, for unknown reasons a small group of SLE patients is refractory to immunosuppressive therapy. In these cases finding an effective treatment becomes a challenge. The progress in therapeutic antibody technology has led to the production of a wide array of humanized monoclonal antibodies, targeting specific cell types or pathways, initiating a new era in the treatment of autoimmune disorders. In contrast to general immuno-suppression, the availability of drugs interfering with specific pathogenetic pathways gives the possibility to choose therapies tailored to each disease in each patient.     

Same or different? Semantic verbal fluency across Spanish-speakers from different countries

Several investigations have suggested that age, education and culture affect semantic fluency. To date, there is no research work indicating whether there are differences among speakers of the same language but from different countries. It has been proposed that despite having the same language, each Spanish-speaking country should have its normative data. The purpose of this study was to analyze the contribution of age, education and culture to semantic fluency in Spanish-speakers. Age and level of education are determining factors in semantic fluency performance. The differences found may be due to the variability in the administration and scoring of the tests, rather than to a cultural effect. A standardized method is proposed for the application of the test.     

A single pacemaker can produce different rates of reentrainment in different overt rhythms

SUMMARY  Using a simple Van der Pol oscillator, we show that periodic events triggered by different states of the oscillator can reentrain at different rates following a phase shift of the Zeitgeber. Such differences can emerge due to waveform distortion during reentrainment, due to masking and due to fitting procedures (e.g. acrophase determination). Therefore, different rates of reentrainment are consistent with single pacemaker models of circadian systems. Likewise, "Fractional Desynchron-ization" can yield different "ranges of entrainment" in different overt rhythms generated by the same pacemaker.     

Dyslipidaemia in poly cystic ovarian syndrome: different groups, different aetiologies?

The objective was to study the pathophysiology of the dyslipidaemiain polycystic ovarian syndrome (PCOS) patients, and to determinehow it is related to hyperinsulin-aemia, hyperandrogenism anddehydroepiandrosterone sulphate (DHEA-S) concentrations. Thelipoprotein lipid profile, anthropometric measurements, endocrineprofile and the presence of insulin resistance were evaluatedin 31 PCOS patients and 20 age-matched healthy women, who servedas controls. PCOS patients had higher fasting insulin concentrations,higher body mass indexes (BMI) and were hyperlipidaemic, withhigher total cholesterol, low density lipoprotein (LDL) andtriglyceride (TG) concentrations. There were no relationshipsbetween plasma lipids and anthropometric variables in the patientgroup as a whole. Insulin-resistant (IR) and non-ER (NIR) PCOSpatients were then evaluated separately. Obesity with markedhyperandrogenism were the predominant features in patients withIR. NIR patients were not obese and had significantly less hyperandrogenism.The adrenal androgen DHEA-S was at the upper limit of its normalrange in both groups. However, both PCOS subgroups exhibitedsimilar significant abnormalities in terms of their lipid parameters.Insulin and DHEA-S concentrations were positively correlatedwith total cholesterol, LDL and TG, and negatively correlatedwith high density lipoprotein, in IR patients. In NIR subjects,insulin was not correlated with any of the lipids and DHEA-Swas negatively related to cholesterol and LDL. Anthropometricvariables were related to lipids in only the NIR patients. ThusPCOS subjects as a group exhibit dyslipidaemia, characterizedby increased total cholesterol, LDL and TG concentrations. Whendivided into IR and NIR subjects, there were no differencesin the degree of lipid abnormalities, despite significant variationsin the BMI and androgen status. Thus, in PCOS subjects, dyslipidaemiamay occur irrespective of insulin resistance. Insulin and DHEA-Sconcentrations were positively correlated with an atherogeniclipid profile in the IR group only. As distinct from syndromeX when IR was present, dyslipidaemia was not related to bodyweight or the waist:hip ratio. In the NTR group there was norelationship between lipids and insulin; DHEA-S, on the otherhand, was negatively related to cholesterol and LDL concentrations.Thus, dyslipidaemla in PCOS patients may occur irrespectiveof insulin resistance, and may have different metabolic aetiologiesdepending on DHEA-S metabolism. It remains to be seen whetherthe two types of PCOS are associated with different risks forischaemic heart disease.     

Nitric oxide produces different actions in different areas of the periaqueductal grey in cats

beta-Amyloid (betaA) induced oxidative stress is a well-established pathway of neuronal cell death in Alzheimer's disease. From turmeric, Curcuma longa L. (Zingiberaceae), three curcuminoids, curcumin, demethoxycurcumin, and bisdemethoxycurcumin, were found to protect PC12 rat pheochromocytoma and normal human umbilical vein endothelial (HUVEC) cells from betaA(1-42) insult, as measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction assay. ED(50) values of curcumin, demethoxycurcumin, and bisdemethoxycurcumin toward PC12 and HUVEC cells were 7.1+/-0.3, 4.7+/-0.1, 3.5+/-0.2 microg/ml and 6.8+/-0.4, 4.2+/-0.3, and 3.0+/-0.3 microg/ml, respectively. These compounds were better antioxidants than alpha-tocopherol as determined by DPPH radical trapping experiment. alpha-Tocopherol did not protect the cells from betaA(1-42) insult even at>50 microg/ml concentration. The results suggest that these compounds may be protecting the cells from betaA(1-42) insult through antioxidant pathway.     

Replicating neuroblastoma cells in different cell cycle phases display different vulnerability to amyloid toxicity

A key role of mitotic activation in neuronal cell death in early stages of Alzheimer's disease (AD) has been suggested. Apparently, terminally differentiated neurons are precluded from mitotic division, yet some phenotypic markers of cell cycling are present in AD-vulnerable brain areas. In this paper, we investigated whether dividing human neuroblastoma cells are preferentially vulnerable to amyloid aggregate toxicity in some specific cell cycle stage(s). Our data indicate that Abeta1-40/42 aggregates added to the cell culture media bind to the plasma membrane and are internalized faster in the S than in the G2/M and G1 cells possibly as a result of a lower content in membrane cholesterol in the former. Earlier and sharper increases in reactive oxygen species production triggered a membrane oxidative injury and a significant impairment of antioxidant capacity, eventually culminating with apoptotic activation in S and, to a lesser extent, in G2/M exposed cells. G1 cells appeared more resistant to the amyloid-induced oxidative attack possibly because of their higher antioxidant capacity. The high vulnerability of S cells to aggregate toxicity extends previous data suggesting that neuronal loss in AD could result from mitotic reactivation of terminally differentiated neurons with arrest in the S phase.