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[Appendico vesical fistula (author's transl)].

Appendico vesical fistula is an uncommon clinical entity which concerns not only the general and urological surgeons but also the general practitioner. It develops as a complication of untreated appendicitis and may go unrecognized for many years. The chief clinical feature is recurrent episodes of acute cystitis. It may occur at any age but usually in the younger group. The frequent absence of pneumaturia and fecaluria helps to distinguish it from other variants of entero-vesical fistula. Appendectomy and excision of the fistula are usually followed by complete recovery.

Adult↗

Micronodular Kaposi's sarcoma - a new variant of classic-sporadic Kaposi's sarcoma.

Kaposi's sarcoma (KS) in its classic-sporadic form is a rare vascular neoplasm affecting predominantly elderly men of Jewish or Mediterranean origin. Women are very rarely affected by KS. The tumor manifests itself most commonly with brownish macular or infiltrated oval lesions on the lower legs in both genders. Human herpesvirus 8 (HHV-8) has recently been demonstrated to be etiologically linked to KS. We report a 51-year-old HIV-seronegative Caucasian woman with an unusual, previously not described variant of KS which presented with small (3 mm in diameter) scattered firm red papules on her right arm. The histology with nodular spindle cell tumor expressing endothelial markers, the demonstration of serum antibodies against HHV-8 and the presence of viral nucleic acids in the lesional tissue proved the diagnosis of the nodular stage of KS. An indolent course characterized by clinically identical seasonal recurrences, even after surgical treatment and cryosurgery, was observed during the follow-up period of 9 years. We propose the term 'micronodular KS' for this unusual clinical variant of KS mimicking capillary hemangioma.

Antibodies, Viral↗

Myxopapillary ependymoma of the lateral ventricle with local recurrences: histopathological and ultrastructural analysis of a case.

An exceptional case of a recurrent intracranial ependymoma of myxopapillary type arising from the lateral ventricle is reported in a 37-year-old man. This distinctive morphological variant of ependymoma is virtually restricted to the region of cauda equina and filum terminale or occasionally to pre- or post-sacral soft tissue. The intracranial cases of myxopapillary ependymoma are extremely rare and are generally associated with the primary ependymal tumour at the typical lumbosacral site. This case of intraventricular myxopapillary ependymoma did not demonstrate any MRI evidence of a primary spinal cord tumour. Moreover, the initial diagnosis of this histologically benign tumour was followed by two tumour recurrences during the three-year follow-up period. To our knowledge, this is the third documented case of a primary intraventricular myxopapillary ependymoma and the first one of intracranial localisation associated with local recurrences.

Adult↗

Liver transplantation for primary hepatocellular carcinoma: tumor size and number determine outcome.

Liver transplantation for primary hepatocellular carcinoma (HCC) has in general been complicated by high recurrence rates. In the present study results from experience of 87 patients were analyzed [56 cirrhotic, 31 non-cirrhotic, 6 with the fibrolamellar (FL) variant] in relation to curative potential. Sixty-two survived > 90 days and form the study cohort. Fifty-six had non-fibrolamellar HCC and, of these, 39 had discrete lesions, measuring 0.8-21 cm (median 5.0 cm) including 4 in whom the diagnosis was made after examination of the explanted liver; 23 had multifocal lesions (> 2 tumor masses). There was no tumor recurrence in the group of 14 cases with single dominant lesions measuring < 4 cm, whereas in the 15 cases with lesions of 4-8 cm the recurrence rate was 40%, and 78% in those > 8 cm and the multifocal lesions (n = 27, P = 0.0001). Five-year actuarial survival figures were 57.1%, 44.4% and 11.1% (P < 0.003) respectively. The mean survival times in patients who died of recurrence were: 4-8 cm, 3.3 years (range 10 months to 6.3 years); > 8 cm or multifocal, 13 months (3-25 months). Reduction of serum alpha-fetoprotein (AFP) to normal levels does not exclude a later recurrence (7 of 17 cases) and this was documented after maintenance of normal AFP levels for up to 29 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Carcinoma, Hepatocellular↗

Diffuse sclerosing variant of papillary carcinoma of the thyroid. Clinical importance, surgical treatment, and follow-up study.

A diffuse sclerosing variant is not very rare among papillary carcinomas of the thyroid when the patients are female and younger than 30 years of age. The variant is characterized by diffuse involvement of one or both thyroid lobes, with dense sclerosis, patchy lymphocytic infiltration, and abundant psammoma bodies. Controversy still exists concerning its prognosis. We reviewed our experience with 14 patients treated between 1958 and 1988. All patients were young females, their age being from 10 to 28 years with a mean of 19.6. Hashimoto's thyroiditis had been suspected in nine patients before they came to our clinic. Nowadays the diagnosis of this cancer is possible when we have this entity in mind and detect abundant psammoma bodies either by ultrasonography or by soft-tissue roentgenography of the neck. Total thyroidectomy with modified neck dissection was carried out in eight patients, subtotal thyroidectomy with neck dissection in five, and lobectomy with neck dissection in one. All of them are alive and well without distant metastasis at a mean follow-up of 16 years. Because most of the patients with this variant of papillary carcinoma are young women and the prognosis is favorable, a complete resection without causing later recurrence, but also cosmetic and complication-free surgery, should be considered.

Adolescent↗

Genetic dissection of psychopathological symptoms: insomnia in mood disorders and CLOCK gene polymorphism.

We investigated the possible effect of the 3111T/C CLOCK gene polymorphism on sleep disorders in a sample of 620 patients affected by major depressive disorder (MDD) and bipolar disorder (BP). We detected a significantly higher recurrence of initial (P = 0.0001), middle (P = 0.0009), and early (P = 0.0008) insomnia in homozygotes for the C variant and a similar trend concerning decreased need of sleep in BP (P = 0.0074). Other demographic and clinical features were found not related with CLOCK polymorphisms. This preliminary observation leads to hypothesize a possible involvement of the CLOCK gene polymorphism in the sleep disregulations in MDD and BP.

Adult↗

Methylenetetrahydrofolate reductase C677T polymorphism and the risk of unexplained recurrent pregnancy loss: a meta-analysis.

OBJECTIVE: To investigate the association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and the risk of unexplained recurrent pregnancy loss (URPL). DESIGN: Meta-analysis of published case-control studies of the MTHFR C677T variant and URPL risk. SETTING: A research institution in China. PATIENT(S): Women with URPL. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Odds ratios (ORs) and 95% confidence intervals (CIs) for TT versus CC genotype, CT versus CC genotype, TT versus CT and CC genotype combined, and for T versus C allele. RESULT(S): Twenty-six studies with 2120 URPL cases and 2949 controls were included. Overall random-effects ORs of 1.49 (95% CI, 1.12-2.00) for TT versus CC genotype, 1.40 (95% CI, 1.11-1.77) for TT versus CT and CC genotype combined, and 1.21 (95%CI, 1.04-1.40) for T versus C allele were found. Stratified analysis showed that significant strong associations between MTHFR C677T polymorphism and URPL were present only in the five Chinese studies (OR = 2.96 for TT versus CC genotype; OR = 2.30 for TT versus CT+CC genotype; OR = 1.73 for T versus C allele), but not in any other studies, including the studies conducted in the European countries. CONCLUSION(S): The MTHFR C677T mutation is not a genetic risk factor for URPL except in a Chinese population.

Abortion, Habitual↗

Hyper-expansion of asparagines correlates with an abundance of proteins with prion-like domains in Plasmodium falciparum.

Plasmodium falciparum encodes approximately 5300 proteins of which approximately 35% have repeats of amino acids, significantly higher than in other fully sequenced eukaryotes. The proportion of proteins with amino acid homorepeats varies from 4 to 54% amongst different functional classes of proteins. These homorepeats are dominated by asparagines, which are selected over lysines despite equivalent AT codon content. Surprisingly, asparagine repeats are absent from the variant surface antigen protein families of PfEMP1s, Stevors and Rifins. The PfEMP1 protein family is instead rich in recurrences of glutamates, similar to human cell surface proteins. Structural mapping of homorepeats suggests that these segments are likely to form surface exposed structures that protrude from the main protein cores. We also found an abundance of asparagine-rich prion-like domains in P. falciparum, significantly larger than in any other eukaryote. Domains rich in glutamines and asparagines have an innate predisposition to form self-propagating amyloid fibers, which are involved both in prion-based inheritance and in human neurodegenerative disorders. Nearly 24% (1302 polypeptides) of P. falciparum proteins contain prion-forming or prion-inducing domains, in comparison to Drosophila (approximately 3.4%) which to date showed the highest number of prion-like proteins. The unexpected properties of P. falciparum revealed here open new avenues for investigating parasite biology.

Amino Acid Sequence↗

Loss of the TEL/ETV6 gene by a second translocation in ALL patients with t(12;21).

Inactivation of the non translocated TEL/ETV6 gene is commonly associated with translocation (12;21) of acute lymphoblastic leukemia (ALL). Translocations involving the short arm of chromosome 12 were analysed in two children with t(12;21) ALL. Fluorescence in situ hybridation studies showed that these associated translocations resulted in loss of TEL/ETV6. While hybridization with a YAC probe covering TEL/ETV6 was positive in one patient, analysis with cosmid probes covering the gene demonstrated that the gene was in fact deleted. It is concluded that deletions involving TEL/ETV6 can remain undetected by FISH using only YAC probes.

Adolescent↗

Minimal residual disease studies are beneficial in the follow-up of TEL/AML1 patients with B-precursor acute lymphoblastic leukaemia.

The t(12;21)(p13;q22) translocation has been identified as the most common chromosomal abnormality in childhood acute lymphoblastic leukaemia (ALL). Initially, several investigators reported an excellent prognosis in paediatric leukaemias with this translocation, but other studies showed a 20% incidence in relapsed ALL. We performed an extensive analysis of 90 ALL patients. In 17 (19%) cases a TEL/AML1 fusion was found. However, this group was not representative as it included a high number of relapsed patients compared with the normal incidence in B-precursor ALL [54 in continuous complete remission (CCR) and 36 relapsed patients] and only a slightly better prognosis for TEL/AML1-positive patients was found (not significant) (four relapses in 17 TEL/AML1-positive patients vs. 32 relapses in 73 TEL/AML1-negative patients). Comparison of known prognostic factors (age, sex, ploidy, white blood cell count and immunophenotype) between relapsed TEL/AML1-positive and TEL/AML1-positive patients in CCR did not reveal differences, except that the white blood cell count was significantly higher in the relapsed group (P = 0.001). Time between diagnosis and relapse was not different for the relapsed TEL/AML1-positive group vs. the relapsed TEL/AML1-negative group. In 11 TEL/AML1-positive patients, the minimal residual disease (MRD) level at the end of induction therapy was quantified in a limiting dilution assay using IGH or TCRD junctional regions as polymerase chain reaction (PCR) targets. In all four relapsed patients, the level of MRD at the end of induction therapy was high (range 0.24-1.2%), whereas in all seven CCR patients, the MRD level was extremely low (0.02 to < 0.001%). In agreement with previous studies in which MRD levels at the end of induction therapy were found to be the strongest risk factor independent of other risk factors, in the present study we show that the MRD level remains a risk factor independent of the presence of a TEL/AML1 fusion gene.

Chromosomes, Human, Pair 12↗

Analysis of two polymorphisms in the promoter region of matrix metalloproteinase 1 and 3 genes in women with endometriosis.

BACKGROUND: Matrix metalloproteinases are a family of proteolytic enzymes that can degrade extracellular matrix components and have been implicated in connective tissue remodeling associated with cancer invasion and metastasis. These proteins are also involved in the invasive events underlying endometriotic lesion formation and aggressive behavior. Given the established genetic background of endometriosis, the aim of this study was to examine the potential impact of two polymorphisms in the gene promoter region of two of these enzymes, matrix metalloproteinases 1 and 3, on predisposition and severity of the disease. METHODS: Genomic DNA was obtained from 56 Italian Caucasian women with a surgical diagnosis of endometriosis and a control group of 71 age-matched Caucasian healthy female blood donors. In control women, endometriosis was ruled out by evaluation of the medical history, gynecologic examinations, and ultrasound scanning. Two polymorphisms have been specifically investigated: 1. a single insertion polymorphism (2G) in the matrix metalloproteinase-1 promoter region known to elevate transcriptional level of matrix metalloproteinase-1; and 2. a single insertion/deletion polymorphism (5A/6A) located in the promoter of the matrix metalloproteinase-3 gene with functional significance in the regulation of its expression. Genotypes were determined by PCR amplification and sequence analysis. RESULTS: Allele and genotype frequencies of both polymorphisms did not significantly differ between endometriosis and control groups. Moreover, no significant difference for both polymorphisms was observed in relation to the clinical stage and recurrence status of the disease. CONCLUSIONS: This is the first study that has evaluated the possibility that gene variants of matrix metalloproteinases might be involved in the susceptibility to endometriosis. However, these results suggest that matrix metalloproteinases 1 and 3 promoter polymorphism do not constitute an important factor for the genetic predisposition to endometriosis and its invasive behavior in the Italian population.

Adult↗

Large-scale simulation of coverage and error rate tradeoffs for cancer detection in cell-free DNA whole-genome sequencing.

MOTIVATION: Cell-free DNA (cfDNA) whole-genome sequencing (WGS) is a promising approach for detecting cancer recurrence. It enables cancer detection by identifying all tumor-derived cfDNA (ctDNA) molecules carrying somatic single nucleotide variants (sSNVs). While ideally, a sequencing platform should be highly accurate for reliable ctDNA detection, in reality, all sequencing platforms introduce sequencing errors that generate false positives indistinguishable from true SNVs. Understanding how sequencing parameters influence ctDNA detection sensitivity at low tumor fractions (TFs) in cfDNA samples is essential for guiding sequencing strategies in clinical contexts. To model cfDNA sequencing for tumor detection, which contains asymmetric noise and multiple interacting parameters, analytical modeling is intractable, motivating large-scale parallelized simulation. RESULTS: We developed a simulation framework to generate in silico cfDNA data across 10 cancer types. In total, 480 million cfDNA samples were simulated from tumor WGS profiles. Overall, the lowest detectable TF differs substantially between cancer types under identical sequencing conditions due to variations in mutational load. For cancers with high mutational load, 3&#xd7; coverage with low-error techniques reliably detects TFs below 0.1%. In contrast, cancers with low mutational load require at least six-fold higher coverage to achieve comparable detection thresholds. Increasing sequencing quality scores from Q30 to Q55 at 30&#xd7; coverage further enhances sensitivity, enabling detection of TFs as low as 1&#x2009;&#xd7;&#x2009;10-5. This study provides a comprehensive framework for optimizing sequencing parameters, offering valuable guidance for tailoring future technology development for specific cancer types and clinical applications. AVAILABILITY AND IMPLEMENTATION: The code is publicly available at https://github.com/UMCUGenetics/cfdetect/tree/main.

Whole Genome Sequencing↗

Evolution of virulence of a plant RNA virus in developmental stage-structured host populations.

Natural host populations are age-structured, and developmental stages differ in susceptibility and within-host pathogen dynamics, potentially imposing distinct selective pressures on viruses. However, the evolutionary consequences of host age structure remain poorly understood. We experimentally evolved turnip mosaic potyvirus for 5 passages in Arabidopsis thaliana populations spanning 7 demographic regimes, from juvenile- to mature-dominated cohorts. We quantified disease progression, symptom severity, and viral load, cross-inoculated evolved lineages across host stages to construct infection matrices, and performed whole-population sequencing at passages 1 and 5. Disease traits changed markedly with passage, demography, and their interaction. Disease progression evolved faster in older populations, whereas symptom severity was independent of median age, indicating demographic reweighting of virulence components. Viral load increased across passages and positively correlated with severity, linking within-host fitness to symptoms. Cross-inoculation assays revealed a modular infection network: juvenile-evolved lineages specialized on juvenile hosts, whereas lineages from intermediate and older populations were more generalist. Genomically, we detected both parallel and demography-specific adaptations, including recurrent changes in the viral protein VPg (involved in translation, replication, and host interactions) as well as synonymous variants showing consistent or opposing selection across host population stage structures. Overall, host age structure emerges as a major ecological driver of virulence evolution, shaping tradeoffs between disease progression and severity and determining specialization versus generalism. These results integrate phenotypic and genomic responses and suggest that manipulating crop age structure could steer virus evolution toward less damaging outcomes.

Virulence↗

Extensive F-18 FDG uptake in metastatic spindle cell carcinoma of the lung.

A 77-year-old man with stage IIB squamous cell carcinoma of the lung underwent right upper lobectomy. One month later he was examined for right chest pain, dyspnea, cough, and weakness. A roentgenogram showed nondiagnostic diffuse opacification of his right lung cavity. An F-18 FDG positron emission tomographic (PET) study revealed extensive uptake in the right pleural area, left adrenal gland, right axilla, and soft tissues consistent with extensive local recurrence and metastatic disease. Biopsy of a right chest soft tissue lesion showed spindle cell carcinoma, a rare variant of squamous cell carcinoma.

Aged↗

Identification of FBN1 gene mutations in patients with ectopia lentis and marfanoid habitus.

BACKGROUND: Marfan syndrome (MFS), inherited as an autosomal dominant trait, typically affects the cardiovascular, skeletal, and ocular systems. Ectopia lentis (EL) is a clinical manifestation of MFS, with stretching or disruption of the lenticular zonular filaments, leading to displacement of the lenses. EL, with or without minor skeletal changes, exists as an independent autosomal dominant phenotype linked to the same FBN1 locus. METHODS: A consecutive series of 11 patients, affected predominantly by EL, was analysed for FBN1 mutations using PCR, SSCA, and sequencing. RESULTS: Six mutations were identified, of which three are novel and one is recurrent in two patients, thus establishing a mutation incidence in this group of 7/11 (63%). CONCLUSION: The FBN1 variants reported are clustered in the first 15 exons of the gene, while FBN1 mutations reported in the literature are distributed throughout the entire length of the gene. A different type of FBN1 mutation presents in this group of patients, compared with MFS, with arginine to cysteine substitutions appearing frequently.

Adult↗

TEL deletion analysis supports a novel view of relapse in childhood acute lymphoblastic leukemia.

PURPOSE: TEL (ETV6)-AML1 (RUNX1) chimeric gene fusions are frequent genetic abnormalities in childhood acute lymphoblastic leukemia (ALL). They often arise prenatally as early events or initiating events and are complemented by secondary postnatal genetic events of which deletion of the non-rearranged, second TEL allele is the most common. This consistent sequence of molecular pathogenesis facilitates an analysis of the clonal origins of relapse in this leukemia, which has some unusual clinical features. EXPERIMENTAL DESIGN: We compared the boundaries, by microsatellite mapping, of TEL deletions at relapse versus diagnosis in 15 informative patients. Moreover, we compared the relatedness of diagnostic and relapse clones using immunoglobulin and T-cell receptor genes rearrangements and clonotypic TEL-AML1 genomic fusion. RESULTS: Five patients retained the apparent same size TEL deletion, seven had larger deletions, and three had smaller deletions at relapse. In all of the cases evaluated, the clonal relatedness of diagnostic and relapse cells was confirmed by the retention of clonotypic TEL-AML1 genomic sequence and/or at least one identical immunoreceptor gene rearrangement. CONCLUSIONS: These data provide further evidence that TEL deletions are secondary to TEL-AML1 fusions in ALL. They are compatible with the novel idea that in at least some cases of childhood ALL, remission occurs with persistence of a preleukemic "fetal" clone, and subsequent relapse reflects the emergence of a new subclone from this reservoir after an independent "second hit," i.e., independent TEL deletion. To our knowledge, the study is the most extensive and comprehensive analysis of the relationship between diagnostic and relapse clones in childhood ALL presented thus far.

Artificial Gene Fusion↗

Immunogenotype changes prevail in relapses of young children with TEL-AML1-positive acute lymphoblastic leukemia and derive mainly from clonal selection.

PURPOSE: Variations of the immunogenotype and TEL deletions in children with TEL-AML1+ acute lymphoblastic leukemia support the hypothesis that relapses derive from a persistent TEL-AML1+ preleukemic/leukemic clone rather than a resistant leukemia. We aimed at elucidating the relationship between the immunogenotype patterns at diagnosis and relapse as well as their clinical and biological relevance. PATIENTS AND METHODS: Immunoglobulin and T-cell receptor gene rearrangements were analyzed in 41 children with a TEL-AML1+ acute lymphoblastic leukemia and an early (up to 30 months after diagnosis; n = 12) or late (at 30 months or later; n = 29) disease recurrence by a standardized PCR approach. RESULTS: In 68% of the patients (group I), we identified differences in the immunogenotype patterns, whereas no changes were observed in the remaining 32% (group II). The divergence resulted more often from clonal selection than clonal evolution and consisted predominantly of losses (0-6, median 5) and/or gains (0-4, median 1) of rearrangements. The frequency and number of clonal immunoglobulin/T-cell receptor rearrangements in group I was higher at diagnosis (2-13, median 5) than at relapse (2-7, median 4), whereas it was the lowest in group II (1-5, median 3). Although group I children were younger at diagnosis, there was no correlation between particular immunogenotype patterns and remission duration. CONCLUSION: These findings imply that the clonal heterogeneity in younger children most likely reflects an ongoing high recombinatorial activity in the preleukemic/leukemic cells, whereas the more uniform repertoire observed in older children mirrors end-stage rearrangement patterns of selected cell clones that evolved during the prolonged latency period.

Adolescent↗