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Non-glial specificities of immunocytochemistry for the glial fibrillary acidic protein (GFAP). Triple expression of GFAP, vimentin and cytokeratins in papillary meningioma and metastasizing renal carcinoma.

In an extensive immunocytochemistry study for glial fibrillary acidic protein (GFAP) of human neuropathological biopsy or autopsy tissue specimens examined for diagnostic or research purposes, rare non-glial specificities of the GFAP immunostain were observed: Schwann cells of some small nerves in salivary gland, renal capsule, and in epidural fat adjacent to a metastatic carcinoma, Schwann and satellite cells in a spinal ganglion invaded by tumor, chondrocytes of epiglottic cartilage, few cells of a malignant pleomorphic adenoma of salivary gland, most cells of a recurrent papillary meningioma with areas similar to the hemangiopericytic variant, and many cells of a renal carcinoma metastatic to brain; the primary renal tumor had been operated 4 years earlier and focally contained some GFAP-positive cells. To ascertain the specificity of such unexpected immunoreactivities for GFAP and to exclude possible crossreactivities with other intermediate filament (IF) proteins, a panel of different antibodies was used for immunocytochemistry with the peroxidase-antiperoxidase (polyclonal antisera) or labeled biotin-avidin (monoclonal antibodies) techniques: two monoclonal and four polyclonal anti-GFAP, three monoclonal and one polyclonal anti-cytokeratins (CK), and two monoclonal anti-vimentin (VIM) antibodies. Triple expression of GFAP, VIM and CK was found in the papillary meningioma (in patterns suggesting frequent co-localization), in the metastatic carcinoma (in patterns suggesting little co-localization), and in the pleomorphic adenoma (only few GFAP-positive cells). Co-expression of GFAP and VIM was seen in epiglottic chondrocytes and reactive astroglia; another metastatic carcinoma was labeled only for CKs. In the light of previous reports on non-glial specificities of the GFAP immunostain, and of the consistency of our immunostaining results obtained by all monospecific anti-GFAP antibodies as well as the lack of immunocytochemically evident crossreactivity with other IF proteins, authentic GFAP production by some rare non-glial tissues and tumors is suggested.

Aged↗

Pseudomonas aeruginosa in the oral cavity and sputum of patients with cystic fibrosis.

Patients with cystic fibrosis (CF) are often hosts to colonies of both mucoid and nonmucoid strains of Pseudomonas aeruginosa. The major pathogens for chronic and recurrent pulmonary infection in these patients are the mucoid variants of P. aeruginosa. Of the 31 CF patients studied, 14 patients yielded both mucoid and nonmucoid strains of P. aeruginosa from the various oral ecologic sites and saliva. Of the sites tested, the dorsum of the tongue gave the highest yield of P. aeruginosa (27 strains), followed by the buccal mucosa (17 strains), saliva (15 strains), and dental plaques (6 strains). Eleven patients had P. aeruginosa in the oral cavity and sputum simultaneously. Antibiotic susceptibility tests on these multiple isolates suggest that CF patients may be cocolonized or coinfected by two or more strains of P. aeruginosa. Therefore, it may be important to identify multiple isolates of P. aeruginosa, not only from sputum cultures but also from oral cultures, for antibiotic-susceptibility testing. Oral colonization by the mucoid variants of P. aeruginosa may lead to further colonization in the lower respiratory tract and subsequent pulmonary infection in CF patients.

Adolescent↗

Ossifying fibroma: a clinicopathologic study of sixty-four cases.

Sixty-four cases of neoplastic benign fibro-osseous lesions are presented, with clinical and radiographic follow-up in 23 instances. A marked predilection for female patients was observed, with the majority or cases arising in the molar-premolar region of the mandible. Radiographically, these neoplasms are well demarcated and may be radiolucent, radiolucent with central opacification (target appearance), or multilocular radiolucent. A benign fibro-osseous histopathologic pattern is observed with osseous, cemental, and/or ovoid-curvoid calcified deposits. This feature, along with confinement to tooth-bearing regions, supports a periodontal ligament origin. It appears that the distinction between cementifying and ossifying variants is academic, as no behavioral differences exist. The recurrence rate following curettage was found to be 28%.

Adolescent↗

[Solitary fibrous tumor -- report of two cases].

Solitary Fibrous Tumor is a rare neoplasm derived from mesenchymal cell. To achieve a diagnosis and to differentiate from others neoplasm immunohistochemical analysis is needed. The majority of these tumours are benign, and complete surgical resection remains the mainstay of therapy for both the benign and malignant variants. However, there are cases of local and distant recurrences, so patients should have a close follow-up and it is far incorrect to look at this lesion as definitely benign. The authors review clinical presentation, radiological features, histological findings, and treatment options for this tumor and report two clinical cases discussing the differences between them.

Adult↗

alpha1-Antitrypsin null alleles: evidence for the recurrence of the L353fsX376 mutation and a novel G-->A transition in position +1 of intron IC affecting normal mRNA splicing.

alpha1-Antitrypsin (PI) deficiency is a common autosomal recessive disorder associated with emphysema and liver disease, which may result from a wide spectrum of mutations causing a reduction of serum levels (deficient alleles) or a total lack of circulating protein (null alleles). We report two different alleles associated with the absence of isoelectric focusing banding patterns in Portuguese patients with emphysema. The first allele, Q0(ourém), results from the recurrence of the defining mutation of the Q0(mattawa) variant (L353fsX376) on a M3 normal background. The second allele, Q0(porto), has a novel G-->A mutation at position +1 of the intron IC (IVS1C+1G-->A), which restricts mononuclear phagocyte transcripts to mRNA species resulting from the direct splice of exon IA to exon II. The absence of this normal splice alternative in the liver, where PI is primarily synthesized, provides a basis for the pathogenic effects of this mutation.

Emphysema↗

Dermatofibrosarcoma protuberans: how wide is wide in surgical excision?

Dermatofibrosarcoma protuberans is a rare mesenchimal tumour mainly characterized by its local aggressiveness and high reported recurrence rates. Classically, wide excisional surgery with at least 3 cm of free tissue margins is recommended as treatment. We present a series of 18 patients with variable gross free tissue margins but confirmed histological free margins in all cases whatever the surgical excision really was. Only one patient presented a local recurrence (5.5%) of a very large (14 cm) sarcomatous variant of dermatofibrosarcoma protuberans. Mean follow-up in this series was 52.1 months. Those results emphasize that histological rather than theoretical "golden rules" are mandatory to locally control this aggressive neoplasm.

Adult↗

Malignant blue naevus with distant subcutaneous metastasis.

Malignant blue naevus is a distinct but rarely documented variant of malignant melanoma, and we describe the triple recurrence of a suprapatellar cellular blue naevus over 12 years in a middle-aged woman. Staging investigations revealed a distant subcutaneous metastasis of the right thigh. Immunohistochemistry of the primary lesion and all recurrences showed S-100, HMB-45, NKI/C-3 and Ki-67 positive cells. However, non-malignant cellular blue naevi from five consecutive other patients were all Ki-67 negative. The change from negative to positive Ki-67 responsivity may therefore be a valuable marker of malignant and metastatic potential in early cellular blue naevi.

Female↗

Induction of L forms of Haemophilus influenzae in culture and their demonstration in human bronchial secretions.

Transitional forms and round bodies of Haemophilus influenzae were identified in sputa from patients with chronic bronchitis who were receiving penicillin therapy for H. influenzae infections. In vitro growth of L forms of this organism was induced by penicillin and glycine and was studied for comparison with development in vivo. Variant forms demonstrated in sputum were similar to variant forms observed in penicillin-induced L colonies. Recurrence of infection after cessation of therapy was related to reversion of persisting L forms to bacillary forms. That these forms were derived from H. influenzae was established by direct staining with fluoresceinlabeled specific antibody. This demonstration that transitional forms and round bodies of H. influenzae occurred in vivo suggests that L forms of bacteria may be significant in chronic or recurrent infections.

Bronchitis↗

Soft sweeps III: the signature of positive selection from recurrent mutation.

Polymorphism data can be used to identify loci at which a beneficial allele has recently gone to fixation, given that an accurate description of the signature of selection is available. In the classical model that is used, a favored allele derives from a single mutational origin. This ignores the fact that beneficial alleles can enter a population recurrently by mutation during the selective phase. In this study, we present a combination of analytical and simulation results to demonstrate the effect of adaptation from recurrent mutation on summary statistics for polymorphism data from a linked neutral locus. We also analyze the power of standard neutrality tests based on the frequency spectrum or on linkage disequilibrium (LD) under this scenario. For recurrent beneficial mutation at biologically realistic rates, we find substantial deviations from the classical pattern of a selective sweep from a single new mutation. Deviations from neutrality in the level of polymorphism and in the frequency spectrum are much less pronounced than in the classical sweep pattern. In contrast, for levels of LD, the signature is even stronger if recurrent beneficial mutation plays a role. We suggest a variant of existing LD tests that increases their power to detect this signature.

Alleles↗

[Autosomal chronic granulomatous disease: case report and mutation analysis of two Brazilian siblings].

OBJECTIVE: To report the case of two siblings with chronic granulomatous disease. Chronic granulomatous disease is a primary immunodeficiency disorder characterized by abnormal microbicidal activity. Mutations in the p47-phox gene (NCF-1) are present in about 30% of the patients with chronic granulomatous disease; this group presents a better prognosis and later onset of recurrent infections as compared with the X-linked variant, present in about 56% of patients. DESCRIPTION: Case 1 is a female presenting repeat infections since age 10, starting with impetigo followed by severe pneumonia six months later. The severity of the lung infection associated with liver abscess and the patient's resistance to treatment prompted laboratory investigation for immunodeficiency. The results of the nitroblue tetrazolium and superoxide release tests were consistent with a diagnosis of chronic granulomatous disease. The parents and siblings were assessed, revealing the presence of granulomatous disease in a brother (Case 2). He also presented repeat infections with impetigo at age 10, followed by pneumonia six months later, however in a non severe form. Single-strand conformational polymorphism analysis detected abnormal electrophoretic mobility of exon 2 of the NCF-1 gene. Sequence DNA analysis revealed a dinucleotide GT deletion in exon 2. COMMENTS: It is important to evaluate the relatives of chronic granulomatous disease patients, even in the absence of typical clinical signs. Defining the mutation and its correlation with phenotype is important to provide appropriate genetic counseling and clinical prognosis.

Anions↗

[Successful treatment of Stewart-Treves syndrome with liposomal doxorubicin].

The Stewart-Treves syndrome (STS) is a lymphedema-associated angiosarcoma which usually develops in female patients after mastectomy and axillary lymph node dissection. A 55-year old woman developed STS in her lymphedematous left arm seven years after breast-preserving surgery with axillary lymph node dissection and radiotherapy. Various therapies which have been employed are radiotherapy and isolated limb perfusion with cytostatic agents. Since our patient had a huge lesion with additional chest wall involvement, neither approach represented a good option. Radiological staging showed no evidence of further lesions or metastases. We started infusion therapy with liposomal doxorubicin (20 mg/m2 body surface) fort six cycles at regular intervals of 14 days. The patient tolerated the therapy well. Palmar-plantar erythrodysesthesia, a well-known side effect of doxorubicin, did develop. Because the disease was stable, the therapy interval was increased to six weeks after the 6th cycle. The patient has shown no recurrence for eight months. STS is a very rare variant of an angiosarcoma with poor prognosis. The case report shows that liposomal doxorubicin provides an effective therapeutic option.

Antibiotics, Antineoplastic↗

Variant chronic granulomatous disease: modulation of the neutrophil defect by severe infection.

The present studies document the cellular and biochemical processes involved in granulocyte O2- production in three patients from two kindreds with variant chronic granulomatous disease (CGD). Rates of O2- production were 9% to 30% of normal, depending on the individual tested and the stimulus; the two brothers from one family responded to each stimulus with rates very similar to each other. Kinetic analysis of NADPH-dependent O2- production in subcellular fractions revealed all three to have NADPH oxidases with both diminished substrate affinity for NADPH (high Kmapp) and decreased maximal velocities of O2- production. Their granulocytes had normal lag times for activation of the respiratory burst but abnormal rates of stimulus-induced membrane depolarization. Cytochrome b was not found in granulocytes or subcellular fractions despite the use of a spectrophotometric assay sensitive enough to detect the cytochrome if its content were proportional to the residual rate of O2- generation. A striking finding in one patient from each kindred was a threefold to tenfold decrease in the rate of O2- production accompanying serious infection. The residual O2(-)-generating activity of CGD variants helps to explain their relative freedom from the recurrent infections of the classic disease. However, the marked decrease described in the present study indicates the potential for a vicious cycle in which an infection, once established, leads to increasing impairment of host defense.

Abscess↗

Influence of interleukin-10 genetic polymorphism on survival rates in melanoma patients with advanced disease.

Individual ability to produce interleukin-10 (IL-10) may be of relevance in the development and evolution of cutaneous melanoma, probably due to its immunosuppressor and anti-angiogenic properties. Single nucleotide polymorphisms at positions -1082 (G/A), -819 (C/T) and -592 (C/A) in the IL-10 gene promoter were analysed in 100 healthy individuals and 98 melanoma patients using fluorogenic hybridization-specific probes in a 'real-time' thermocycler. Polymorphic frequencies were correlated with various prognostic factors and overall survival. The frequency of IL-10 polymorphic variants was similar in patients and controls. However, high producer genotypes at the -1082 position were over-represented in males with an older age at diagnosis. The analysis of the promoter genotypes in patients stratified according to clinical prognostic factors did not show any associations, although a trend (not statistically significant) towards a prolonged survival in patients genotyped as high IL-10 producers was observed. In addition, the low producer -1082AA genotype was significantly associated with decreased survival in patients with advanced disease. Similarly, the presence of this genotype shortened the overall survival in males after recurrence or metastasis development. In conclusion, the frequency of genetic variants in the IL-10 gene promoter was not associated with melanoma appearance, but conditioned the age at diagnosis in males and the overall survival in patients with advanced disease.

Adult↗

Variant of intron 22 inversions in the factor VIII gene in severe hemophilia A.

Recurrent DNA inversions, which disrupt the factor VIII (FVIII) gene, generally occur between a region of intron 22 (int22h) and one of two homologous copies of this region, located 300 to 400 kb telomeric to the FVIII gene. This report describes a patient with severe hemophilia A and a high level inhibitor with atypical hybridization patterns. A Bcl I Southern blot assay was altered to 17.5, 16, and 14 kb. His mother and two out of four aunts tested had normal and abnormal restriction patterns which led to a total of five different fragments, suggesting that they were carriers. The Xba I plus Kpn I restriction fragment-length polymorphism in intron 22 by Southern blotting using the same probe (probe a) yielded the 6.2 kb polymorphic band, with a clearly separated 6.6 kb band from the non-factor VIII region; an alternative int22h hybridization probe (probe x) detected no additional fragment. These results suggest that probe a as well as probe x could recognize an intron-22-sized fragment. This report shows a variation in the number of int22h copies although we could not find the inversion junction.

Adult↗

Short-coupled variant of torsade de pointes.

Presented in this paper were 3 cases of a special kind of polymorphic ventricular tachycardia (VT). The clinical manifestation was recurrent syncope without organic heart disease. The electrocardiogram (ECG) was characterized by normal QT intervals with short-coupled variant of torsade de pointes. The efficacy of treatment with class I, II, III antiarrhythmic drugs was not apparent but verapamil had an excellent therapeutic effect for it. This kind of VT had a high incidence of sudden death, so it was very important for physicians to identify and treat it promptly with long-term verapamil. The mechanism of short-coupled variant of torsade de pointes was unclear. It probably had some relationship with triggered activity or imbalance of autonomic nervous system.

Adult↗

In vivo immunologic selection of proviral gene deletion variants from a nonproducer clone.

The mechanism by which tumors recur at sites of injection of retrovirus-infected fibrosarcoma cell lines was investigated. Previously, it was established that tumor recurrences reflect outgrowth of rare cells that lack viral antigens and are susceptible to superinfection with the homologous retrovirus. In the present study clones isolated from a retrovirus-infected cell line were evaluated as precursors for tumor recurrence. Under conditions of in vivo immunologic selection, a clone that contained a single abbreviated copy of the provirus formed variants that lacked the proviral gene. Tumor variants lacking the proviral gene grew progressively in both nonimmune and virus-immune male Sewall Wright strain 2 guinea pigs. Tumor recurrence could be prevented by superinfection of the virus-infected fibrosarcoma cell line or by superinfection of the precursor for tumor recurrence. Cell lines infected with retroviruses varied in frequency of tumor recurrence formation. This model may be useful in analyzing gene deletion as a mechanism of tumor escape from host immunologic attack.

Animals↗

Clinical features associated with metastasis and recurrence of differentiated thyroid cancer in children, adolescents and young adults.

OBJECTIVE: Differentiated thyroid cancer (DTC), including papillary (PTC) and follicular (FTC) variants, is unusual in children and accounts for only 10% of all cases. For that reason, knowledge of the clinical features which predict recurrence is limited. We reviewed 170 cases of childhood DTC to determine if specific clinical or pathological findings were associated with increased risk of recurrence. DESIGN: This was a retrospective study of children and adolescents with DTC registered in the Department of Defense Automated Centralized Tumor Registry. PATIENTS: We reviewed 137 cases of PTC and 33 cases of FTC diagnosed between 1953 and 1996 at < or = 21 years of age. RESULTS: In the PTC group (median follow-up 6.6 years, range 2 month-39.5 years), only one patient died, but 21 developed local and 6 developed distant recurrence. By univariate analysis, recurrence was more common in patients with multifocal (odds ratio 7.5) or large tumours (odds ratio 4.1), and in those with palpable cervical lymphadenopathy (odds ratio 3.0) or metastasis at diagnosis (odds ratio 2.8). By multivariate analysis focality was the best predictor of recurrence (P = 0.0019). In the FTC group (median follow-up 5 years, range 6 month-38.1 years), no patient died of disease, but 5 developed recurrence. As with PTC, recurrence was more likely in patients with multifocal tumours (odds ratio 22.0). CONCLUSIONS: Differentiated thyroid cancer in children and adolescents has low mortality, but a high risk of recurrence. Young patients with large, multifocal tumours that are already metastatic at diagnosis have the greatest risk of recurrence.

Adenocarcinoma, Follicular↗

Genomic and epigenomic diversity of breast cancer across Western and MENA populations: implications for precision oncology.

Breast cancer is the most common malignancy in women worldwide and is increasingly recognized as a biologically diverse disease shaped by both molecular and ancestral context. Women from the Middle East and North Africa (MENA) populations, including Saudi Arabia, often present at a younger age and with more aggressive subtypes such as HER2-positive and triple-negative breast cancer (TNBC) compared with Western cohorts. These clinical patterns reflect a distinctive genomic background marked by high consanguinity, founder mutations in key susceptibility genes, and population-specific somatic alterations that are not fully captured in global reference datasets. This review brings together current evidence on somatic, germline, transcriptomic, and epigenomic diversity in breast cancer across Western and MENA populations, with a focus on Saudi cohorts. Drawing on a previously published systematic review of more than 2,500 MENA breast cancer cases, TP53 accounted for approximately 24% and PIK3CA for roughly 10% of curated somatic mutation records pooled across 44 studies (proportions of mutation calls, not per-patient prevalence); in a separate single-center Saudi cohort, only 3.7% of patients underwent BRCA testing, and 37.5% of this clinically selected, testing-referred subgroup carried a pathogenic variant, a figure that should not be read as general-population BRCA prevalence. Variants of uncertain significance exceeded 20% across several regional genomic studies. We summarize conserved driver events, such as recurrent TP53 and PIK3CA mutations, while highlighting regional features, including unique stop-gain and loss-of-function variants, a high copy-number burden, and early-onset disease linked to ancestral architecture. We also discuss emerging data on MENA-specific regulatory signatures, including immune-enriched and basal-myo transcriptomic clusters, CIMP-like methylation patterns, and non-coding RNA networks; these associations are numerically suggestive in available cohorts but have not reached statistical significance in existing studies and warrant validation in larger, dedicated MENA/Saudi cohorts before being considered established determinants of treatment response and resistance. Finally, we examine the clinical implications of this diversity for biomarker development, pharmacogenomics, and access to targeted therapies, and outline practical steps toward ancestry-aware precision oncology in the region.

BRCA↗