PCR testing for Treponema pallidum in paraffin-embedded skin biopsy specimens: test design and impact on the diagnosis of syphilis
Background: Syphilis, a chronic infection caused by Treponema pallidum (T. pallidum), is a disease which is increasing in incidence, and thus more and more becoming a differential diagnosis in routine pathology. Aim: Since histological changes are not specific, we sought to develop a polymerase chain reaction (PCR)-based molecular assay for the detection of T. pallidum in formalin-fixed, paraffin-embedded tissues, and evaluate its diagnostic power, especially in comparison with other ancillary methods, i.e. immunohistochemistry and Dieterle staining. Methods: 36 skin biopsies with the clinical and /or serological diagnosis of syphilis were evaluated by morphology, immunohistochemistry and s…
Hepatitis E Virus Detection in Liver Tissue from Patients with Suspected Drug-Induced Liver Injury
Hepatitis E virus (HEV) infection is increasingly recognized as a cause of acute hepatitis in the industrialized world. We aimed to determine the frequency of acute Hepatitis E virus (HEV) infection in cases of suspected drug-induced liver injury (DILI), mainly a diagnosis of exclusion. To this aim, formalin-fixed, paraffin-embedded (FFPE) liver tissues of all cases routinely processed in our institute during a 2 ½ years period in which DILI was amongst the differential diagnoses (157 liver biopsies, one liver explant) were subjected to semi-nested RT-PCR for the detection of hepatitis E virus (HEV) RNA. Histopathology was re-evaluated on all cases tested positive. HEV RNA was detectable in…
Actinomyces in infected osteoradionecrosis--underestimated?
Infected osteoradionecrosis (IORN) is a severe complication of radiation therapy for head and neck cancer. Infected osteoradionecrosis can lead to fracture and often requires subsequent jaw resection. It is known that irradiated bone is highly susceptible to infections, mainly with Candida species and cariogenic bacteria. Only very few data exist on Actinomyces in IORN. The study population consisted of 31 patients (7 female, 24 male; median age, 58.3 years). All patients exhibited clinical and radiological signs of IORN (infection, mucosa or skin fistula, and sequestrated bone). To detect Actinomyces colonies, histological examination was performed using several staining procedures (hemato…
Bcl-xL and Myeloid cell leukaemia-1 contribute to apoptosis resistance of colorectal cancer cells
AIM: To explore the role of Bcl-x(L) and Myeloid cell leukaemia (Mcl)-1 for the apoptosis resistance of colorectal carcinoma (CRC) cells towards current treatment modalities. METHODS: Bcl-x(L) and Mcl-1 mRNA and protein expression were analyzed in CRC cell lines as well as human CRC tissue by Western blot, quantitative PCR and immunohistochemistry. Bcl-x(L) and Mcl-1 protein expression was knocked down or increased in CRC cell lines by applying specific siRNAs or expression plasmids, respectively. After modulation of protein expression, CRC cells were treated with chemotherapeutic agents, an antagonistic epidermal growth factor receptor (EGFR1) antibody, an EGFR1 tyrosine kinase inhibitor, …
Decreased Fibrogenesis After Treatment with Pirfenidone in a Newly Developed Mouse Model of Intestinal Fibrosis
BACKGROUND Fibrosis as a common problem in patients with Crohn's disease is a result of an imbalance toward excessive tissue repair. At present, there is no specific treatment option. Pirfenidone is approved for the treatment of idiopathic pulmonary fibrosis with both antifibrotic and anti-inflammatory effects. We subsequently investigated the impact of pirfenidone treatment on development of fibrosis in a new mouse model of intestinal fibrosis. METHODS Small bowel resections from donor mice were transplanted subcutaneously into the neck of recipients. Animals received either pirfenidone (100 mg/kg, three times daily, orally) or vehicle. RESULTS After administration of pirfenidone, a signif…
TFIIH Operates through an Expanded Proximal Promoter To Fine-Tune c-myc Expression
A continuous stream of activating and repressing signals is processed by the transcription complex paused at the promoter of the c-myc proto-oncogene. The general transcription factor IIH (TFIIH) is held at promoters prior to promoter escape and so is well situated to channel the input of activators and repressors to modulate c-myc expression. We have compared cells expressing only a mutated p89 (xeroderma pigmentosum complementation group B [XPB]), the largest TFIIH subunit, with the same cells functionally complemented with the wild-type protein (XPB/wt-p89). Here, we show structural, compositional, and functional differences in transcription complexes between XPB and XPB/wt-89 cells at t…
In vitro effects of putative neurotransmitters on synaptic ribbon numbers and N-acetyltransferase activity in the rat pineal gland
The pineal contains a large number of classical transmitters and neuropeptides. Some of these neurochemicals are involved in the regulation of serotonin N-acetyltransferase (NAT) activity and hence in melatonin synthesis. Synaptic ribbons present in the pineal gland also exhibit a numerical day/night rhythm parallel to that of NAT activity. There is scarcity of information regarding the regulation of synaptic ribbon (SR) numbers. In the present study, we have investigated in vitro effects of a number of classical neurotransmitters and neuropeptides. NAT activity was used to monitor melatonin synthesis under the experimental conditions used. Norepinephrine (NE), Delta sleep-inducing peptide …
Osteonecrosis of the jaws in patients treated with bisphosphonates - histomorphologic analysis in comparison with infected osteoradionecrosis.
Background: Patients treated with bisphosphonates because of bone metastases have been shown to develop osteonecrosis of the jaws. In the present study, we examined the histologic findings of these cases. As similarities between this disorder and infected osteoradionecrosis (IORN) are described, both lesions were compared. Methods: We investigated eight patients with bisphosphonate treatment and osteonecrosis (four female, four male; median age: 65.6 years; cancer: multiple myeloma in five patients, breast cancer in three patients; mandibular involvement in five patients, maxillar involvement in three cases), and 10 patients suffering from IORN (all male; median age: 61.3 years; cancer: s…
Bone Marrow Findings in Multicentric Castleman Disease in HIV-negative Patients
Because bone marrow histology in multicentric Castleman disease in human immunodeficiency virus-negative patients is not well reported, we investigated sequential bone marrow biopsies of 3 affected human immunodeficiency virus-negative patients, of which one was human herpes virus 8 (HHV8)-positive. The histologic evaluation of the bone marrow revealed lymphoid follicles with regressed germinal centers in 1 patient. Another patient showed tumorlike but bland polyclonal plasmacytosis with large perivascular plasma cell clusters. The HHV8-positive patient revealed interstitial HHV8-positive cells accompanied by a mild plasmacytosis. The atypical lymphoid follicles could be regarded as a bone …
Hepatocyte-specific deletion of the antiapoptotic protein myeloid cell leukemia-1 triggers proliferation and hepatocarcinogenesis in mice
Regulation of hepatocellular apoptosis is crucial for liver homeostasis. Increased sensitivity of hepatocytes toward apoptosis results in chronic liver injury, whereas apoptosis resistance is linked to hepatocarcinogenesis and nonresponsiveness to therapy-induced cell death. Recently, we have demonstrated an essential role of the antiapoptotic Bcl-2 family member Myeloid cell leukemia-1 (Mcl-1) in hepatocyte survival. In mice lacking Mcl-1 specifically in hepatocytes (Mcl-1Δhep), spontaneous apoptosis caused severe liver damage. Here, we demonstrate that chronically increased apoptosis of hepatocytes coincides with strong hepatocyte proliferation resulting in hepatocellular carcinoma (HCC).…
Suppression of Mcl-1 via RNA interference sensitizes human hepatocellular carcinoma cells towards apoptosis induction
Abstract Background Hepatocelluar carcinoma (HCC) is one of the most common cancers worldwide and a major cause of cancer-related mortality. HCC is highly resistant to currently available chemotherapeutic drugs. Defects in apoptosis signaling contribute to this resistance. Myeloid cell leukemia-1 (Mcl-1) is an anti-apoptotic member of the Bcl-2 protein family which interferes with mitochondrial activation. In a previous study we have shown that Mcl-1 is highly expressed in tissues of human HCC. In this study, we manipulated expression of the Mcl-1 protein in HCC cells by RNA interference and analyzed its impact on apoptosis sensitivity of HCC cells in vitro. Methods RNA interference was per…
Lack of effect of oxytocin on the numbers of ?synaptic? ribbons, cyclic guanosine monophosphate and serotonin N-acetyltransferase activity in organ-cultured pineals of three strains of rats
In addition to the stimulating influence of the sympathetic system on the function of the mammalian pineal gland, neuropeptides such as neuropeptide Y, vasoactive intestinal polypeptide and arginine-vasopressin (AVP) are thought to function as modulators. Since AVP has been shown to influence pineal melatonin synthesis, the aim of the present study was to investigate the possible effects of the second hypothalamic nonapeptide oxytocin (OT), which likewise has been detected in the pineal gland. We therefore studied "synaptic" ribbon (SR) numbers, N-acetyltransferase (NAT) activity and the intracellular concentration of cyclic guanosine monophosphate (cGMP) following in vitro incubation of ra…
Swelling of the buccal cheek: an unusual presentation of primary tuberculosis.
Effects of topical treatment with the raft modulator miltefosine and clobetasol in cutaneous mastocytosis: a randomized, double-blind, placebo-controlled trial
Background Mastocytosis is characterized by the accumulation and activation of mast cells in different organs, most commonly the skin. Miltefosine, a raft modulator, has recently been shown to inhibit the activation of mast cells and to reduce mast cell-driven skin inflammatory responses. Objectives To study the safety and efficacy of topical miltefosine treatment of skin lesions in patients with mastocytosis. Methods Thirty-nine adult patients with mastocytosis with skin involvement were treated in a double-blind, placebo-controlled, parallel trial with topical miltefosine and clobetasol for 2 weeks. Treatment areas were analysed for changes in skin lesions and symptoms following mechanica…
Knockout of myeloid cell leukemia-1 induces liver damage and increases apoptosis susceptibility of murine hepatocytes
Apoptosis, or programmed cell death, regulates tissue development and homeostasis in multi-cellular organisms. Extrinsic or intrinsic death signals activate pro-apoptotic pathways, resulting in the activation of caspases and finally in cell death. An important event during apoptosis process is the permeabilization of the outer mitochondrial membrane (OMM). Integrity of the OMM is regulated by the Bcl-2 protein family, which is divided into three groups: anti-apoptotic members Bcl-2, Bcl-xL and myeloid cell leukemia-1 (Mcl-1), pro-apoptotic multidomain members Bax and Bak, and pro-apoptotic BH3-only proteins. Mitochondrial activation is regulated by selective interactions of Bcl-2 proteins v…
Pattern analysis of human cutaneous mast cell populations by total body surface mapping.
SummaryBackground Mast cells (MCs), critical effector cells in allergic inflammation and innate immunity to bacteria, are located in large numbers in tissues that interface the external environment, including the skin. However, little is known about the distribution and numbers of human skin MCs. Objectives To assess the influence of age, sex and skin region on size and spatial distribution of MC populations in normal human skin. Methods Biopsies of healthy skin were obtained from 150 male and female individuals (age range 10–86 years). MCs were quantified and mapped planimetrically by histomorphometry in 15 anatomical sites (abdomen, thorax, lower and upper back, lower and upper arm, lower…
A dual role of caspase-8 in triggering and sensing proliferation-associated DNA damage, a key determinant of liver cancer development.
Summary Concomitant hepatocyte apoptosis and regeneration is a hallmark of chronic liver diseases (CLDs) predisposing to hepatocellular carcinoma (HCC). Here, we mechanistically link caspase-8-dependent apoptosis to HCC development via proliferation- and replication-associated DNA damage. Proliferation-associated replication stress, DNA damage, and genetic instability are detectable in CLDs before any neoplastic changes occur. Accumulated levels of hepatocyte apoptosis determine and predict subsequent hepatocarcinogenesis. Proliferation-associated DNA damage is sensed by a complex comprising caspase-8, FADD, c-FLIP, and a kinase-dependent function of RIPK1. This platform requires a non-apop…
Involvement of B cells in Non-Alcoholic Steatohepatitis (NASH)
Mcl-1 is an anti-apoptotic factor for human hepatocellular carcinoma
Defects in apoptosis signaling in hepatocytes contribute to tumorigenesis in hepatocellular carcinoma (HCC). In addition, treatment with chemotherapeutic drugs is often ineffective in HCC patients due to the apoptosis resistance of cancer cells. Anti-apoptotic members of the Bcl-2 family, including myeloid cell leukemia-1 (Mcl-1), which regulate intrinsic apoptosis induction at the mito-chondrial level, are often overexpressed in human cancer, and are implicated with disease grade and prognosis. Yet, little is known about the role of Mcl-1 in HCC. In this study, we analyzed the relevance of Mcl-1 expression for the apop-tosis resistance of human HCC. Mcl-1 protein expression was considerabl…