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At least 1,477 records · Page 82Linked to original sources
PubMed2004

Severe factor X deficiency in pregnancy: case report and review of the literature.

Isolate factor X deficiency is an extremely rare clotting factor disorder inherited in autosomal recessive fashion and pregnancy in a homozygous patient is frequently complicated by recurrent miscarriage, uterine bleeding and premature labour. Eleven pregnancies in seven patients affected by FX deficiency have been reported in the literature. Two additional pregnancies have been reported in a FX variant (FX Friuli). We present a new case of successful at term pregnancy in a homozygous patient.

Adult↗
PubMed2004

August 2003: 47-year-old female with a 7-year history of osteomalacia and hypophosphatemia.

The August 2003 COM. A 47-year-old woman presented with a long history of muscle pain, weakness, and visual disturbances. Over the last year, she developed diplopia and left sixth nerve palsy. No other neuro-ophthalmologic abnormalities were found. Past medical and family history was unremarkable. Laboratory investigation disclosed hypophosphatemia, phosphaturia, elevated serum alkaline phosphatase activity, and normal serum calcium levels. CT scans showed a lobulated mass arising on the meningeal surface of the cavernous sinus, measuring 3x 2 x 2 cm. The lesion was partially resected and microscopic examination revealed a highly vascularized tumor composed of primitive mesenchymal cells arranged whether in a patternless-pattern or surrounding thin-walled, branching vascular spaces and thick-walled hyalinized vessels. Other eye-catching features were microcystic areas, multinucleated osteoclastic-like giant cells, scattered islands of mature adipocytes, foci of hemorrhage, thrombosed medium-sized-to-large vessels, and hemosiderin-laden macrophages. After surgery, the patient recovered from the muscle pain and weakness, with a significant improvement of serum calcium and alkaline phosphatase levels and phosphate blood levels. Taken together, the clinical and pathologic features were consistent with a diagnosis of phosphaturic mesenchymal tumor (mixed connective tissue variant) of the cavernous sinus in a setting of oncogenic osteomalacia. No further treatment was carried out. The patient has been followed for the last 4 years with no evidence of recurrent disease. Oncogenic osteomalacia is a rare clinical entity characterized by hypophosphatemia, phosphaturia, and a low concentration of 1,25-dihydroxyvitamin D(3) caused by a neoplasm. Pathologists should be aware of this entity, because surgical excision of the tumor is usually curative.

Brain Neoplasms↗
PubMed1987

Clinical isolate of herpes simplex virus type 2 that induces a thymidine kinase with altered substrate specificity.

In vitro and in vivo studies were done on a herpes simplex virus type 2 strain recovered from a patient on acyclovir (ACV) which was ACV resistant but expressed thymidine (dThd) kinase (EC 2.7.1.21) activity. Plaque-purified clones derived from the original clinical sample were heterogeneous with respect to plaque size and drug susceptibility. The heterogeneity of this viral mixture was also evident from varied 125I-labeled 5-iodo-2'-deoxycytidine autoradiographic patterns and from varied expression of dThd kinase-associated phosphorylating activities. Four clones from this mixture were 1-beta-D-arabinofuranosylthymine (ara-T) susceptible and ACV resistant. Extracts of cells infected with these clones catalyzed the phosphorylation of ara-T but little of ACV. The virus-coded dThd kinase was purified from one of these clones to determine whether its substrate specificity was altered. The amount of virus-coded dThd phosphorylating activity with the cell extracts was estimated to be sevenfold lower with the resistant clone than with the MS strain of herpes simplex virus type 2. The dThd kinase eluted from a dThd-agarose affinity column under the same conditions with extracts from both sources and substrate saturations of both enzymes by acyclic nucleoside analog phosphate acceptors were classical hyperbolic functions. However, there were significant differences in the kinetic parameters of substrates between the two enzymes. Apparent Km (Km') values for dThd, deoxycytidine, ara-T, ACV, and the acyclic guanosine analog 9-[[2-hydroxyl-1-(hydroxymethyl)ethoxy]methyl]guaine (BW B759U) were 2- to 60-fold higher with the variant enzyme than with the enzyme from laboratory strain MS. Comparing these two enzymes, relative maximal phosphorylation rates (Vm) were eightfold lower for ACV but unchanged for BW B759U. In contrast, the relative rates for deoxycytidine and ara-T were eight- and twofold higher, respectively. The surprisingly good substrate activity with BW B759U compared with that of ACV (Vm/Km' = 0.39 versus 0.01) coincided with susceptibility of the ACV-resistant virus to BW B759U. This clinical variant retained its pathogenicity for mice and was only moderately less neurovirulent than wild-type virus. Although such mutants have the potential to induce illness less responsive to therapy, the recurrence from which the isolate was obtained was typical for this patient in severity and duration. Since this episode, the patient has been treated successfully with ACV.

Acyclovir↗
PubMed2026

A compound heterozygous combination of SLC34A2 variants in pulmonary alveolar microlithiasis: A case report and literature review.

Pulmonary Alveolar Microlithiasis (PAM) is a rare hereditary lung disorder characterized by the intra-alveolar deposition of calcium phosphate microliths. It is primarily familial and follows an autosomal recessive inheritance pattern, with no significant gender disparity in incidence. In its early stages, PAM is often asymptomatic, and most cases are detected incidentally through abnormal imaging findings during routine health examinations. We report a case of a male patient in his mid-50 s with a 10-year history of exertional dyspnea and cough unresponsive to conventional therapy. Initially diagnosed and treated for emphysema in early 2024, the patient was readmitted two months later with progressive dyspnea and cyanosis. The diagnosis of PAM was confirmed by typical medical imaging and pathological examination. Genetic analysis identified a previously unreported compound heterozygous combination of SLC34A2 variants: a c.910A > T (p.Lys304*) nonsense variant in exon 8 and a heterozygous ∼5.5 kb copy-number deletion at 4p15.2 (encompassing exons 2-6), thereby expanding the catalogue of reported PAM-associated genetic combinations. No recurrence was observed during one-year follow-up after bilateral lung transplantation.

Humans↗
PubMed2026

An alignment-free strategy for circulating tumor DNA detection and tumor fraction estimation from whole-genome sequencing data.

Circulating tumor DNA (ctDNA) is emerging as a promising biomarker for postoperative monitoring of cancer patients. Precise estimation of circulating tumor fraction is crucial for evaluating treatment effects and timely detection of disease recurrence. All current ctDNA detection methods that utilize whole-genome sequencing (WGS) data rely on the reference genome alignment of sequencing reads and often apply separate tools for detecting different variant types. However, various bioinformatic analysis confounders and the application of external variant calling tools could be avoided by analyzing k-mers from unaligned sequencing reads. While k-mer-based methods have successfully been applied for somatic variant validation and detection, the potential of k-mer-based ctDNA detection is unexplored. We have developed a tumor-informed alignment-free ctDNA detection tool called ctDNAmer that detects tumor-specific somatic variation directly from unaligned sequencing data by identifying k-mers unique to the tumor DNA. ctDNAmer detects variant information across the genome by comparing the primary tumor and germline WGS data and accounts for sample-specific germline variability and technical noise in the same framework. We tested the utility of ctDNAmer for tumor fraction estimation on postoperative plasma cfDNA WGS data (mean sequencing depth ~ 28x) from 90 stage III colorectal cancer patients with three years of follow-up. The tumor fraction (TF) estimates agreed with the available clinical information and ctDNA was detected in 77% (17/22) of recurring patients with a median lead time of 8 months compared to radiological imaging. We further validated ctDNAmer's tumor fraction estimates based on a comparison with the mean cfDNA allele frequencies of somatic clonal SNVs identified from aligned primary tumor sequencing data. The TF estimates showed a strong Pearson correlation of 0.897 with the mean allele frequencies and improved ctDNA detection results across samples with an AUC of 0.79 compared to 0.75 if the mean allele frequency of clonal mutations is used.

Circulating Tumor DNA↗
PubMed1999

Protuberant fibro-osseous lesions of the temporal bone: a unique clinicopathologic diagnosis.

OBJECTIVE: The objective of the study was to describe the clinical presentation and treatment of exophytic fibro-osseous temporal bone lesions, a clinical entity never previously reported, and to consider the differential diagnosis. STUDY DESIGN: The design of the study was a retrospective case review. SETTING: The setting was a tertiary referral center. PATIENTS: Two patients diagnosed with exophytic fibro-osseous temporal bone lesions were included in the study. INTERVENTION: The intervention used was surgical excision. MAIN OUTCOME MEASURE: The main outcome measures were clinical, radiographic, and histopathologic examination. RESULTS: There was no evidence of recurrence at 15 and 17 months after surgery. CONCLUSION: Although fibro-osseous lesions of the temporal bone have been previously reported, there have been no reported cases of an exophytic variant.

Adolescent↗
PubMed1983

[Specific active immunotherapy of murine methylcholanthrene-induced sarcoma using a partially purified soluble tumor specific transplantation antigens].

Immunotherapeutic effects of soluble tumor specific transplantation antigens (TSTA) were studied, Crude 3M KC1 extract of C3H/He methylcholanthrene-induced sarcoma (F tumor) was purified by preparative isoelectric focusing (pIEF). The immunoprotective fraction (Fr. 15, pI 5.7-6.0) possessed about 50 fold greater activity than the crude 3M KC1 extract. Three weekly injections of optimal immunoprotective dose of Fr. 15 retarded the outgrowth of F cells and decreased the outgrowth and tumor incidence of rechallenged inoculation in mice completely resected established 1 cm tumor. Weekly injections of Fr. 15 resulted in decreased local recurrences. This therapeutic effect was immunologically specific. Fr. 15 alone did not show the therapeutic effects on the established tumor, but combined treatment with cyclophosphamide gave the increased survivals. A metastatic variant cell line (F-4) metastasized to the lung spontaneously after the resection of primary subcutaneous tumor. Therapeutic injections of Fr. 15 decreased the rates of spontaneous pulmonary metastasis of F-4. Since cross-immunoprotection tests revealed that F and F-4 share the common TSTA, the therapeutic effect of Fr. 15 upon pulmonary metastases might be due to improved host's specific immunity.

Animals↗
PubMedDate not supplied

[Sarcoma consisting of dendritic reticular cells].

Sarcoma consisting of dendritic reticular cells is one of the histiocytic sarcoma variants. In the case reported sarcoma affected axillary lymph nodes in a 20-year-old male. The tumor was surgically removed but recurred 2 years after radiation and polychemotherapy. The recurrent tumor was also surgically removed. Histology of the primary and recurrent tumors was similar. The tumors were studied electron-microscopically and immunohistochemically.

Adult↗
PubMed2026

First nationwide full-genome characterisation of human-derived Andes virus in Chile: a retrospective genomic epidemiology study.

BACKGROUND: Andes virus (ANDV) is the only hantavirus known to transmit between humans and causes hantavirus cardiopulmonary syndrome in Chile and Argentina. In Chile, ANDV genomic diversity remains incompletely characterised. This study aimed to characterise the genetic diversity, geographical structure, and molecular signatures of ANDV using human clinical samples collected over a 13-year period (2011-24). METHODS: We conducted a retrospective genomic epidemiology study of ANDV infections in Chile. Clinical samples from patients with confirmed ANDV, collected between March 9, 2011, and June 27, 2024, were analysed and sequenced. Clinical and epidemiological data were obtained from diagnostic laboratories and surveillance programmes. Consensus sequences for the S, M, and L segments were generated, and genetic clustering and divergence were assessed using phylogenetic inference and variant calling. FINDINGS: We analysed clinical samples from 58 infected individuals and identified two major genomic variants of ANDV with distinct geographical distributions, defined by regionally structured patterns of nucleotide and amino acid substitutions across the S, M, and L segments: ANDV Chi-North (central Chile) and ANDV-South (southern Chile). No consistent clustering by clinical severity was observed, and no recurrent non-synonymous substitutions were uniquely associated with severe disease. Substitutions previously associated with person-to-person transmission in outbreaks in Argentina were not consistently observed in Chilean sequences, including in four person-to-person transmission cases. Although some substitutions described in ANDV-like viruses were present in the Chi-North lineage, this lineage remained phylogenetically distinct and geographically restricted to central Chile. INTERPRETATION: To our knowledge, this study provides the first nationwide genomic characterisation of human-derived ANDV in Chile. The identification of geographically structured variants indicates that ANDV diversity in Chile is driven by regional diversification rather than clinical outcome. The absence of consistent amino acid signatures associated with disease severity or person-to-person transmission suggests that these phenotypes are unlikely to be explained by viral genetic variation alone. These findings refine current understanding of ANDV evolution and highlight the need for continued integrated genomic surveillance in endemic regions. FUNDING: Agencia Nacional de Investigación y Desarrollo de Chile and National Institutes of Health.

Humans↗
PubMed2003

Schwannoma with rhabdomyoblastic differentiation: a unique variant of malignant triton tumor.

A 54-year-old woman presented with intractable perianal, bilateral buttock, and radiating thigh/calf pain. An MRI scan showed an intradural, contrast-enhancing, ovoid mass in the cauda equina region at L1-L2. At laminectomy, the ovoid mass arose from a nerve root and, intact, was gross totally resected. Histologically, the dominant pattern was that of schwannoma. One year thereafter, the symptoms recurred. An MRI scan demonstrated an irregular, heterogeneously enhancing tumor recurrence. A repeat laminectomy disclosed a large fleshy tumor involving multiple nerve roots. The lesion was subtotally resected and showed pluridirectional differentiation toward embryonal rhabdomyosarcoma, primitive neuroectodermal tumor, and rare malignant epithelial cells. Review of the original tumor disclosed only foci of embryonal rhabdomyosarcoma and primitive neuroectodermal tumor. Based upon available data regarding divergent differentiation in peripheral nerve sheath tumors, this is a unique, previously undescribed tumor demonstrating rhabdomyosarcomatous, primitive neuroectodermal tumor and scant epithelial differentiation in a schwannoma. In essence, it is a variant of malignant Triton tumor because of its origin in a tumor consisting of well-differentiated Schwann cells. It supports the contention that the Schwann cell is the source of a variety of heterologous elements in nerve sheath tumors.

Cauda Equina↗
PubMed2002

Primary salivary clear cell tumors--a diagnostic approach: a clinicopathologic and immunohistochemical study of 20 patients with clear cell carcinoma, clear cell myoepithelial carcinoma, and epithelial-myoepithelial carcinoma.

CONTEXT: Primary salivary clear cell tumors comprise an uncommonly encountered subgroup of salivary neoplasia. We hypothesize that clear cell carcinoma does not represent a "monomorphic" variant of epithelial-myoepithelial carcinoma, but is distinct in terms of histogenesis and tumor biology. OBJECTIVES: To compare the clinicopathologic features of 20 cases of salivary primary clear cell tumors, including 12 clear cell carcinomas (CCCs), 7 epithelial-myoepithelial carcinomas (EMECs), and 1 clear cell myoepithelial carcinoma (CCMEC); to investigate their interrelationship with regard to myoepithelial differentiation; and to offer a diagnostic approach for distinguishing between these entities. DESIGN: Retrospective and prospective identification and review of patients diagnosed with primary salivary clear cell neoplasia and review of the English language literature. SETTING: Three academic tertiary-care hospitals. PATIENTS: We identified 12 patients with CCC, 7 with EMEC, and 1 with CCMEC. Patients included 11 men and 9 women, aged 30 to 88 years (median 72.5 years). MAIN OUTCOME MEASURES: Immunohistochemical reactivity for S100, muscle-specific actin, and calponin; ultrastructural examination when feasible; review of patient charts; and telephone interviews to establish clinical outcome. RESULTS: Clear cell carcinoma has a predilection for intraoral sites, whereas EMEC has a predilection for the parotid. All 3 of the tumor types studied have a propensity for locoregional recurrence, which can manifest decades after initial surgery. There were no mortalities among patients with CCC, even after pulmonary metastasis in 2 patients, confirming the indolent nature of this group of clear cell tumors. A meta-analysis of reported cases of CCC, EMEC, and CCMEC confirmed that EMEC and CCMEC have a much greater propensity for locoregional recurrence than CCC, despite the predilection of both for a more surgically accessible site (parotid). We found no definitive evidence of myoepithelial differentiation in CCC, indicating that it is probably morphogenetically distinct from EMEC and CCMEC, both tumors with diagnostically requisite myoepithelial differentiation. CONCLUSIONS: The initial treatment of choice for CCC, CCMEC, and EMEC is surgical resection with negative margins. Locoregional recurrence should be treated aggressively, as it is still consistent with long disease-free intervals. The lack of myoepithelial differentiation in CCC is consistent with the concept that this tumor is histomorphogenically distinct from EMEC and that it is not merely a monomorphic variant.

Adenocarcinoma, Clear Cell↗
PubMed1985

[Clinical picture and treatment of recurrent lymphosarcomas after radiotherapy].

The disease course was assayed in 177 patients with a complete remission after radiotherapy. The conclusion is made about high efficacy of repeated treatment after local radiotherapy. In view of the fact that extranodal areas are often involved during relapses, it is not advisable to irradiate the lymph nodes according to the radical program. Relapses that develop during the first year of remission, manifesting in the renewal of the tumor growth and appearance of new tumors, are prognostically unfavourable variants and require intensive care. Local relapses can be exposed to repeated radiation with a good result.

Adolescent↗
PubMed2004

Atrial natriuretic peptide gene polymorphisms and risk of ischemic stroke in humans.

BACKGROUND AND PURPOSE: A precise definition of genetic factors responsible for common forms of stroke is still lacking. The purpose of the present study was to investigate the contributory role of the genes encoding atrial natriuretic peptide (ANP) and type A natriuretic peptide receptor (NPRA) in humans' susceptibility to develop ischemic stroke. METHODS: Allele and genotype frequencies of ANP and NPRA were characterized in an Italian case-control study with patients affected by vascular disease or risk factors. Subjects were recruited from the island of Sardinia (206 cases, 236 controls). RESULTS: A significant association between the ANP/TC2238 polymorphic site and stroke occurrence was found when a recessive model of inheritance was assumed. The risk conferred by this mutant genotype, when estimated by multivariate logistic regression analysis, was 3.8 (95% confidence interval, 1.4 to 10.9). A significantly increased risk of stroke recurrence was observed among cases carrying the ANP/CC2238 genotype compared with cases carrying the ANP/TT2238 genotype (P=0.04). No direct association of NPRA with stroke occurrence was detected. However, a significant epistatic interaction between the ANP/CC2238 genotype and an allelic variant of NPRA led to a 5.5-fold increased risk of stroke (95% confidence interval, 1.5 to 19.4). CONCLUSIONS: Our findings support a direct contributory role of ANP to stroke in humans. A significant interaction between ANP and NPRA on stroke occurrence was found.

Aged↗
PubMed2006

Peripheral T-cell lymphoma with involvement of the expanded mantle zone.

Peripheral T-cell lymphoma (PTCL) with a nodular architecture is rare. Recently, two variants have been described with infiltration of the B-cell follicle, one variant that localizes to the marginal zone with a so-called perifollicular growth pattern, and a variant that localizes to the germinal center. These lymphomas have a CD4+ phenotype and may express Bcl-6. We have studied five similar cases of PTCL with involvement of the B-cell follicle. However, our cases differ from the cases previously described by their predominant and frequently patchy involvement of the expanded mantle zone of the B-cell follicle at onset. Later biopsies in three of the cases show diffuse infiltration of the lymph node, without features of angioimmunoblastic TCL (AILT). All cases expressed Bcl-6 in addition to CD4. Cytogenetics was available in four of the cases but revealed no recurrent chromosomal aberrations or changes associated with other types of PTCL. No mutations of the BCL-6 gene were observed. Together, the cases seem to have an intermediately aggressive clinical behavior. Whether our cases are part of a spectrum of PTCLs that encompasses previously described variants with predominant marginal zone or germinal center infiltration or they represent a separate T-cell lymphoma type remains to be demonstrated by a study of more of such cases.

Adult↗
PubMed2002

Cutaneous sinus histiocytosis (Rosai-Dorfman disease) presenting clinically as vasculitis.

The cutaneous variant of Rosai-Dorfman disease is a rare benign lymphoproliferative disorder that occurs without lymphadenopathy or internal organ involvement. We present a 55-year-old woman with a diffuse exanthematous eruption that evolved into pruritic papulopetechial and purpuric lesions on the back and lower extremities, diagnosed clinically as a vasculitis. The patient's lesions cleared spontaneously with no recurrence. Histopathologic examination showed a dense dermal nodular lymphohistiocytic infiltrate with occasional eosinophils, plasma cells, and neutrophils and with numerous extravasated red blood cells. The large, foamy histiocytes exhibited abundant pale cytoplasm, feathery cytoplasmic borders, and emperipolesis. A few histiocytes had longitudinal nuclear grooves resembling Langerhans cells; however, these cells were positive for S-100 protein and negative for CD1a. The clinical presentation of the cutaneous variant of Rosai-Dorfman disease is generally nonspecific. We present this case because of the unusual clinical presentation mimicking a vasculitis.

Biopsy, Needle↗