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J Richter

Publications and source records attributed to J Richter.

At least 181 records · Page 10Linked to original sources
PubMed1996

Schistosomiasis in women: manifestations in the upper reproductive tract.

Female genital schistosomiasis (FGS) is a neglected disease entity which may give rise to considerable suffering among women of child-bearing age in areas where schistosomiasis (especially due to Schistosoma haematobium) is prevalent. The close relation between the vessels in genital organs and the urinary bladder enables the parasite to easily change location to virtually any organs in the female pelvic area. Symptoms concur with the anatomical location of worm pairs and their ova. Lesions of the lower female genital tract can easily be investigated by cytology, histology or direct demonstration of eggs in scrapings or biopsies whereas schistosomiasis of the upper genital tract is clinically indecipherable and less accessible for examination. In the literature there are references to FGS as a cause of infertility, complications of pregnancy, menstrual disorders, problems related to sexual intercourse, diagnostic similarities to STDs and cancer, unspecified complaints related to blood loss, chronic abdominal pain, social segregation and related psychological problems. The diagnosis of female upper genital schistosomiasis is difficult and the authors point out possible diagnostic procedures which might be helpful for further understanding of this complex entity.

Abdominal Pain↗
PubMed1996

Female genital schistosomiasis due to Schistosoma haematobium. Clinical and parasitological findings in women in rural Malawi.

A total of 51 women with urinary schistosomiasis haematobium were examined in order to identify diagnostic indicators for female genital schistosomiasis (FGS). Patients were selected at random from the outpatient department of the Mangochi District Hospital, Malawi. The medical histories were recorded according to a pre-designed questionnaire and the women were subjected to a thorough gynaecological examination including colposcopy and photographic documentation of lesions. Microscopy of genital biopsies revealed that 33 of the 51 women had S. haematobium ova in cervix, vagina and/or vulva in addition to the presence of ova in urine. The most sensitive diagnostic procedure was beside microscopic examination of a wet cervix biopsy crushed between two glass slides, which revealed 25 of the 33 genital infections. There was a significant correlation between the size of genital lesions and the number of ova counted per mm2 of crushed tissue. Women with FGS had significantly more tumours in the vulva than women with schistosomiasis limited to the urinary tract. Most of the observed genital pathology could easily be identified by the naked eye, but colposcopic examination yielded valuable additional information like the demonstration of neovascularisation around cervical sandy patches. Few of the symptoms previously regarded as indicators for FGS could be linked to the presence of schistosome ova in genital tissue. Husbands of infertile women with FGS had children with other women significantly more often than husbands of women who only had urinary schistosomiasis. This, together with the finding that the majority of the divorced women had FGS, indicates that the manifestation of this disease may have implications for the marital and sexual life of the affected women.

Adolescent↗
PubMed1996

Female genital schistosomiasis (FGS): relationship between gynecological and histopathological findings.

Schistosomiasis of the lower female reproductive tract manifests itself in a broad spectrum of clinical features. However, clinical and histopathological findings have never been studied in a synoptic manner. Based on the assumption that any type of pathology present in the female reproductive tract is the expression of a complex pathophysiological reaction towards eggs sequestered in the genital tissues, we decided to analyze colposcopic and histopathological findings in a comprehensive manner. Thirty-three women in Malawi with urinary and genital schistosomiasis were examined parasitologically and gynecologically. A thorough colposcopic examination with photodocumentation was performed and biopsies were taken from the cervix, the vagina and/or the vulva for histological sectioning and immunohistochemistry. The predominant colposcopic findings were sandy patches on the cervical surface similar to those seen in the bladder and polypous/papillomatous tumors with irregular surface on the vaginal wall and in the vulvar area. The histopathological sections of sandy-patch-like lesions demonstrated only a small cellular reaction around S. haematobium eggs in various stages of disintegration. In contrast, in the case of polyps the histology revealed a more pronounced immunological reaction characterized by a heavy cellular infiltrate. One case of invasive squamous cell carcinoma of the cervix was diagnosed. We conclude that colposcopy is a useful tool in the detection of FGS related pathology in the lower female reproductive tract and that the synoptic assessment of surface and of corresponding histological sections helped to understand the pathophysiology of S. haematobium associated disease in genital tissue.

Adolescent↗
PubMed1996

Diagnosis of female genital schistosomiasis by indirect disease markers: determination of eosinophil cationic protein, neopterin and IgA in vaginal fluid and swab eluates.

Based on assumptions about the pathophysiology of egg-related lesions in the lower reproductive tract, putative indirect disease markers were investigated in vaginal fluids from 54 Malawi adolescent girls and women infected with S. haematobium. These women received a careful gynecological examination during which biopsies were taken from the cervix, and, if present, also from suspicious lesions in the vagina and the vulva. If the biopsies, either in wet crushed preparations or in histological sections, contained eggs the patients were considered to have female genital schistosomiasis (FGS; n = 33). The remainder (n = 21) were classified as having urinary schistosomiasis only. Eosinophil cationic protein (ECP), a cytotoxic granule protein of eosinophils, neopterin, a second messenger molecule generated during the activation of macrophages, and IgA as an indicator of local B-cell activation were quantitatively determined in vaginal fluid. To clarify the origin of ECP, this protein was also looked for in histological sections by an immunohistochemical method. In order to explore whether such disease markers can be detected after absorption to a tampon-like material, ECP and IgA were also assessed after elution from a non-porous, polypropylene fibre web impregnated with vaginal fluid. The concentration of ECP in vaginal fluid and the degree of immunohistochemical staining in histological sections were significantly higher in patients with FGS than in women with urinary schistosomiasis only. The amount of ECP detected in histological sections correlated to the number of eggs/mm2 of compressed genital tissue (rho = 0.36, P = 0.02), and the concentration of ECP in vaginal fluid correlated to the concentration of neopterin as well as to that of IgA (rho = 0.52, P = 0.004 and rho = 0.37, P = 0.02, respectively). Median neopterin concentration in vaginal fluid was also higher in the FGS group, but the difference was not statistically significant. ECP could also be detected in eluates from impregnated fibre webs, but the concentration was approximately one power of 10 less than in the original vaginal fluid. These results demonstrate that indicators of immunological mechanisms related to the egg-granuloma might be useful as indirect disease markers for women with FGS if assessed in vaginal washings or swab eluates.

Adolescent↗
PubMed1996

Urine reagent strips for diagnosis of schistosomiasis haematobium in women of fertile age.

Hematuria, proteinuria and leukocyturia were semiquantitatively assessed by reagent strips in single morning urine of women of fertile age visiting the outpatient department of the Mangochi district hospital, Malawi. This was part of a diagnostic approach to female genital schistosomiasis (FGS). In 51 women ova of Schistosoma haematobium were detected in urine by a filtration technique. In 33 of these women ova were also present in genital tissue as demonstrated by microscopic examination of biopsies. In 209 women no ova were found in the single urine filtered. There were significantly higher scores for hematuria, proteinuria and leukocyturia as well as of the combined reagent strip index (RSI) in egg-excreting than in egg-negative women. The sensitivity of a single hematuria, proteinuria and leukocyturia reading was 98, 84 and 73%, respectively. However, the respective specificity was only 24, 22 and 23%. The best prediction of urinary schistosomiasis was achieved by a +2 score for hematuria, of which the sensitivity was 94% and the specificity was 61%. The high false-positive rates can probably be explained by contamination of urine by vaginal secretion. Moreover, cases of schistosomiasis have probably been overlooked because only a single morning urine sample was examined. The total absence of hematuria, proteinuria and leukocyturia, however, may be used to rule out heavy infections in community surveys. There was no difference in reagent strip scores between women with genital and urinary schistosomiasis as compared with those with urinary tract lesions alone. Thus urine analysis reagent strip readings do not help to discriminate between S. haematobium infected women with and without FGS.

Adolescent↗
PubMed1996

Reversibility of lower reproductive tract abnormalities in women with Schistosoma haematobium infection after treatment with praziquantel--an interim report.

Little is known whether and to what extent antiparasitic treatment cures female genital schistosomiasis (FGS). Using a standard protocol, of twenty-one women with FGS nine were re-examined at two to nine weeks after they had been treated with praziquantel at a single dose of 40 mg/kg. Symptoms related to pathology of the urinary tract and to a lesser extent of genital pathology subsided in most patients. Schistosoma haematobium ova were no longer detectable in urine of any of the patients post-treatment. Efficiency of chemotherapy against adult worms was confirmed by the disappearance of circulating anodic antigen (CAA) in serum. Sandy patches showed resolution in two of four cases after chemotherapy. Papillomata due to schistosomiasis alone improved, but persisted in mixed infection with human papilloma virus (HPV) or when HPV was the only underlying cause. In one patient ulcera could not be related with certainty to schistosomiasis at admission, but resolved after treatment with parziquantel. Leukoplakia (two cases) was not influenced by chemotherapy, or even increased during follow-up, regardless of whether ova had been detected or not. Although the follow-up period was rather short, time intervals were not standardized, and a relatively small number of patients was investigated, it could be shown that genital pathology due to sequestered S. haematobium ova is, at least partially, reversible already two to nine weeks after killing the adult worms by praziquantel. This is paralleled by a normalization of inflammatory immune responses detectable in histological sections and vaginal lavage.

Adolescent↗
PubMed1996

Effects of ischaemia and preservation on the ultrastructure of the bronchiolar epithelium. A quantitative electron microscopic study of human and canine lungs.

In ten cases of clinical human single-lung transplantation, the nontransplanted Euro-Collins-preserved contralateral lungs were examined using electron microscopy to determine the effects of ischaemia on the bronchiolar epithelium. Existing structural damage at the time of transplantation was characterized using this approach, and nine nonpreserved canine single lungs were also investigated to identify the impact of ischaemia. The study revealed a significant correlation between the duration of ischaemia and the mitochondrial surface-to-volume ratio, which can serve as a morphometric criterion for mitochondrial damage, in canine lungs. However, this correlation was not found in the human donor lungs. Further examination of human donor lungs showed slight to moderate damage to the endoplasmic reticulum and nuclear chromatin. In addition, various degrees of damage to mitochondrial structure, ranging from inconspicuous to severe, were found. The mitochondrial surface-to-volume ratio can be considered to be a suitable criterion for the quantification of ischaemic damage of the bronchiolar epithelium under experimental conditions. Ultrastructural analysis of human donor lungs revealed intact bronchiolar epithelial cell structures at the time of transplantation, reflecting adequate organ preservation with Euro-Collins solution.

Adolescent↗
PubMed1996

[Is functional conservative treatment of stable lateral ankle fractures justified?].

For Weber type B ankle fractures, operative treatment is generally recommended. Yet, there is no general agreement about the role of functional treatment. In a prospective follow-up study from December 1990 to May 1994, 146 patients were reviewed. The mean follow-up time was 17.3 months for clinical examinations and 19.6 months for X-rays. There were no failures. In all, 85 patients (58%) were treated conservatively (group K). A below-the-knee plaster was applied to 23 patients for 6 weeks, and 62 patients had functional treatment with an ankle brace. According to the Olerud Score, the first subgroup (K-plaster) achieved 89.4 points and the last (K-func.) reached 95.7 points. There were no signs of post-traumatic arthritis. 61 patients (42%) had open reduction and internal osteosynthesis (group OP). In 19 patients a plaster immobilization was necessary, and in 42 patients early mobilization was possible. The first subgroup (OP-plaster) achieved 85.0 points in the Olerud Score; the last (OP-func.) achieved 92.4 points. According to the degree of instability following ankle injuries, a new algorithm for treatment of type B ankle fractures is described, emphasizing early mobilization and functional after treatment.

Adult↗
PubMed1996

X-ray absorption and X-ray photoelectron spectroscopy of a rhodium colloid.

Transition metal colloids are potential precursors of heterogeneous catalysts with application to selective chemical reactions. Sample preparation techniques are described. Experimental details are given of the characterization of these often air-sensitive particles by X-ray photoelectron and X-ray absorption spectroscopy. First results obtained with both techniques for a Rh-colloid show that the metal is mainly present in the zerovalent chemical state. But the spectra indicate further chemical states of Rh which can be assigned to the outermost metal atoms of the colloid interacting with organic ligands or to the educt Rh-halides.

Journal Article↗
PubMed1996

Immunological findings in groups of children after compensatory measures.

In 200 children residing permanently in a region with a high level of atmospheric pollution, indicators of humoral immunity, salivary immunity and specific IgE antibodies were determined before and after 14 days' attendance at an "outdoor school" in rural areas with a very low level of atmospheric pollution. A marked reduction of elevated albumine levels, which are characteristic of irritation or even inflammation in the oral cavity or respiratory tract, was found, as well as increasing levels of Slg A and lysozyme in saliva. The two-week stay in the outdoor school resulted in decreased IgE specific antibodies of the respiratory type of allergy (CAP Phadiatop). In the group of atopic children there were found high total IgE levels, with a trend of depression after 2 weeks in the outdoor school. Higher values of some immunoglobulins were observed, while low levels of IgA were found in some children with high frequency of respiratory diseases. The irritant effect of polluted atmosphere and the quality of indoor atmosphere influence some immunological parameters in children.

Adolescent↗
PubMed1996

Cellular edema and alterations in metabolite content in the ischemic and reperfused canine heart following different forms of cardiac arrest.

This study investigates firstly how far cellular edema correlates with parameters of the anaerobic energy turnover independent of the method used for cardiac arrest, and secondly to what extent cellular edema developing during reversible global ischemia is reduced after reperfusion. Canine hearts were arrested 1. by aortic cross clamping (ACC), 2. by coronary perfusion with St. Thomas solution, or 3. HTK (histidine tryptophan ketoglutarate) solution (Custodiol). Samples for biochemical and structural analysis were taken at different times during ischemia and after reperfusion with Tyrode solution. Cellular edema determined morphometrically and given as volume ratio of sarcoplasm and mitochondria to myofibrils (Vvsp + V vmi/Vvmf) varies significantly in the differently arrested hearts. Reperfusion after a decrease in ATP to 4 mumol/gww (revival time) leads to a nearly complete structural recovery. The relationship between cellular edema and defined over-all metabolite tissue concentrations and extracellular pHe values shows: 1. during the decrease of creatine phosphate to 3 mumol/gww, cellular edema does not change; it is, however, significantly higher after ACC and St. Thomas than after HTK perfusion; 2. at each lactate concentration, cellular edema differs significantly depending on the form of cardiac arrest; 3. during the decrease of ATP and pHe cellular edema increases and is comparable at concentrations < 4 mumol/gww and at pHe values < 6.5 independent of the form of cardiac arrest; 4. beyond 10 mumol/gww of inorganic phosphate (Pi), increasing values for cellular edema correspond to defined Pi values in the differently arrested hearts. Thus, the ratio VVSp+ VVMi/VVMf is a powerful parameter for the determination of cellular edema during ischemia, as well as for correlations with metabolic parameters.

Animals↗
PubMed1996

An automated fast MR-imaging method for localized measurements of dose distributions using NMR-Fricke gel dosimetry. Evaluation of influences on the measurement accuracy.

PURPOSE: The calculation of radiation absorbed dose using a chemical dosimeter and NMR-imaging techniques provides non-invasive 3D dosimetry. The main problems with this new method are measurement accuracy and diffusion effects. These involve influences on chemical preparations, correct data acquisition (evaluation of the T1 values) and a lack of methods for reducing diffusion effects. The aim of this study was to develop a computer assisted localized dosimetry method using fast and quantitative NMR-imaging techniques in order to reduce diffusion effects and to determine the accuracy of this new approach. We show successful localized dosimetry experiments and present a new method for the calculation of the diffusion coefficient. MATERIAL AND METHODS: The dosimeter gel contained a modified Fricke solution and was stabilized with gelatin. Several compositions of dosimeter gels and different conditions were investigated in order to optimize the treatment. IR-Snapshot-Flash has been used to determine the T1-values. The diffusion coefficient of the bound ferric ions was estimated by taking advantage of the short acquisition times of this fast NMR-imaging technique. RESULTS: Dependencies of the dosimeter system were investigated. The calculated error limits for evaluation of the measurement accuracy are in the range of 10 to 20%. The accurate localized determination of the T1-values and the diffusion has considerable influence on the measurement. Fast and quantitative NMR-imaging methods for accurate T1-calculations like IR-Snapshot-Flash reduce this effect. CONCLUSION: Our results show the advantage of the use of fast MR-imaging techniques for NMR Fricke dosimetry. The diffusion effects are reduced effectively, so even details can be imaged. We also developed a new method for the calculation of the diffusion coefficient, which can be used for paramagnetic ions in any aqueous solution.

Gels↗
PubMed1996

Sonographic screening for urinary tract abnormalities in patients with Schistosoma haematobium infection: pitfalls in examining pregnant women.

In areas where Schistosoma haematobium is endemic, urinary schistosomiasis and pregnancy are frequently concomitant; however, both these conditions may produce similar urinary tract changes in ultrasound scans and hence their differential diagnosis may be difficult. In patients with urinary schistosomiasis, focal and/or diffuse urinary bladder wall changes are frequently detected ultrasonically. Dilatation of one or both ureters and progressive hydronephrosis may be observed in more severe cases. Satisfactory ultrasound examination of the urinary bladders of pregnant women is generally not feasible because mechanical compression by the fetus or transitory lower urinary tract infection hampers adequate filling of the bladder. Pregnancy itself is frequently associated with dilatation of one or both ureters and/or hydronephrosis; this is due to hormonal factors, infection, or compression of one or both ureters by the enlarged uterus and growing fetus. Hence, when sonography of the urinary bladder is not feasible such pregnancy-associated changes are virtually indistinguishable from those caused by S. haematobium, and may be incorrectly attributed to the latter. Pregnant women, therefore, should be excluded from ultrasonic surveys of urinary schistosomiasis. In contrast, ultrasound scans of adolescents and of women with positive parasitological findings and/or pathological alterations in the urinary tract should include examination of the uterus in order to assess whether the woman is pregnant; thereby, misinterpretation of sonographic findings can be avoided. Pregnant women with significant hydronephrosis must be closely followed up by an obstetrician since this condition may indicate a complication of the pregnancy; in some cases only a postpartum examination will permit definitive diagnosis.

Adolescent↗