CDK9/CYCLIN T1 expression during normal lymphoid differentiation and malignant transformation

CDK9 is a member of the CDC2-like family of kinases. Its cyclin partners are members of the CYCLIN T family (T1, T2a, and T2b) and CYCLIN K. The CDK9/CYCLIN T1 complex is very important in the differentiation programme of several cell types, controlling specific differentiation pathways. Limited data are available regarding the expression of CDK9/CYCLIN T1 in haematopoietic and lymphoid tissues. The aim of this study was to analyse the expression of the CDK9/CYCLIN T1 complex in lymphoid tissue, in order to assess its role in B- and T-cell differentiation and lymphomagenesis. CDK9/CYCLIN T1 expression was found by immunohistochemistry in precursor B and T cells. In peripheral lymphoid tissues, germinal centre cells and scattered B- and T-cell blasts in interfollicular areas expressed CDK9/CYCLIN T1, while mantle cells, plasma cells, and small resting T-lymphocytes displayed no expression of either molecule. CDK9/CYCLIN T1 expression therefore appears to be related to particular stages of lymphoid differentiation/activation. CDK9 and CYCLIN T1 were highly expressed in lymphomas derived from precursor B and T cells, from germinal centre cells, such as follicular lymphomas, and from activated T cells (ie anaplastic large cell lymphomas). Hodgkin and Reed-Sternberg cells of classical Hodgkin's lymphoma also showed strong nuclear staining. Diffuse large B-cell, Burkitt's lymphomas, and peripheral T-cell lymphomas, among T-cell lymphoproliferative disorders, showed a wide range of values. No expression of CDK9 or CYCLIN T1 was detected in mantle cell and marginal zone lymphomas. However, at the mRNA level, an imbalance in the CDK9/CYCLIN T1 ratio was found in follicular lymphoma and diffuse large B-cell lymphomas with germinal centre phenotype, and in the cell lines of classical Hodgkin's lymphomas, Burkitt's lymphomas, and anaplastic large cell lymphoma, in comparison with reactive lymph nodes. These results suggest that the CDK9/CYCLIN T1 complex may affect the activation and differentiation programme of lymphoid cells. The molecular mechanism through which the CDK9/CYCLIN T1 complex is altered in malignant transformation needs to be elucidated.     

VEGF and his R1 and R2 receptors expression in mast cells of oral squamous cells carcinomas and their involvement in tumoral angiogenesis

More than 90% of malignant neoplasms of the oral cavity are squamous carcinomas of oral mucosa and most are conventional type. This study included 60 cases of oral squamous carcinoma processed by usual histological technique and stained with Hematoxylin-Eosin and Alcian Blue-Safranin (Alcian Blue powder from Sigma Aldrich, code A5268-25G) and diagnosed in the Department of Pathology, University of Medicine and Pharmacy of Craiova. Double immunohistochemical (CD105-tryptase, VEGF-, VEGFR1-, VEGFR2-tryptase) or combined histochemical and immunohistochemical reactions (VEGF÷ VEGFR1÷ VEGFR2÷Alcian Blue-Safranin) followed the particular morphological aspects of the mast cells, their relation with the blood vessels and the overlap signal of tryptase and Alcian Blue-Safranin÷VEGF and its R1 and R2 receptors in mast cells. Immunostaining for VEGF and its R1 and R2 receptors was present both in tumor cells and mast cells. Double immunohistochemical-histochemical reactions allowed us angiogenic profiling the mast cells. The signal overlap was present for VEGF-, VEGFR1-, VEGFR2-tryptase intratumoral and tumor invasion front mast cells. Student's t-test for comparison of intratumoral and the invasion front MDM showed highly significant value (p=3.23 E-08). VEGF÷ VEGFR1÷ VEGFR2÷Alcian Blue-Safranin revealed particular morphological aspects of mast cells, in with different morphology, shapes, sizes and degrees of degranulation. Statistical analysis showed a linear correlation between MDM and MVD inside the tumor (Pearson coefficient =0.47) and a weak linear correlation at the front of invasion (Pearson coefficient =0.19). This study has highlighted the importance of mast cells in the tumor growth of the oral squamous carcinomas, especially in terms of their proangiogenic profile (expression of VEGF and its R1 and R2 receptors). In addition, their quantification as MDM makes this parameter a useful prognostic marker.     

Undesirable dental hard tissue effects hypothetically linked to orthodontics - a microscopic study

Like any other medical intervention, the orthodontic treatment may have, besides the positive effects, also unwanted secondary consequences. The aim of this study was to evaluate the changes present in dental hard tissue associated with orthodontic treatment. The stereo-microscopic ex vivo analysis was performed on two sets of maxillary first premolars undergoing orthodontic treatment for a long period of time (12 and 23 months); five teeth with other clinical situations were used as controls. By analyzing the teeth undergoing orthodontics, enamel color alterations were mainly found adjacent to the bracket, more pronounced in the gingival area, suggesting the need for a correct oral hygiene around it. Roughness was higher on the enamel surface corresponding to the bracket's base, aspect linked to the resign impregnation during bonding procedures. At the apical part, changes regarding contour, appearance and surface roughness were noticed. These modifications were suggestive for the presence of apical root resorption. The severity of root resorption was not correlated with the duration of treatment. In conclusion, through microscopic analysis changes that may be associated with orthodontic treatment have been observed in both crown and apical level.     

Outcome of children hospitalized with community-acquired pneumonia treated with aqueous penicillin G

OBJECTIVE:

To describe the evolution and outcome of children hospitalized with community‐acquired pneumonia receiving penicillin .

METHODS:

A search was carried out for all hospitalized community‐acquired pneumonia cases in a 37‐month period. Inclusion criteria comprised age ≥2 months, intravenous penicillin G use at 200,000 IU/kg/day for ≥48 h and chest x‐ray results. Confounders leading to exclusion included underlying debilitating or chronic pulmonary illnesses, nosocomial pneumonia or transference to another hospital. Pneumonia was confirmed if a pulmonary infiltrate or pleural effusion was described by an independent radiologist blind to the clinical information. Data on admission and evolution were entered on a standardized form.

RESULTS:

Of 154 studied cases, 123 (80%) and 40 (26%) had pulmonary infiltrate or pleural effusion, respectively. Penicilli was substituted by other antibiotics in 28 (18%) patients, in whom the sole significant decrease was in the frequency of tachypnea from the first to the second day of treatment (86% vs. 50%, p = 0.008). Among patients treated exclusively with penicillin G, fever (46% vs. 26%, p = 0.002), tachypnea (74% vs. 59%, p = 0.003), chest indrawing (29% vs. 13%, p<0.001) and nasal flaring (10% vs. 1.6%, p = 0.001) frequencies significantly decreased from admission to the first day of treatment. Patients treated with other antimicrobial agents stayed longer in the hospital than those treated solely with penicillin G (16±6 vs. 8±4 days, p<0.001, mean difference (95% confidence interval) 8 (6–10)). None of the studied patients died.

CONCLUSION:

Penicillin G successfully treated 82% (126/154) of the study group and improvement was marked on the first day of treatment.     

Differentiation of monocytes into CD1a- dendritic cells correlates with disease progression in HIV-infected patients

Monocyte differentiation into dendritic cells (DCs) depends on microenvironmental conditions. In this study, the capacity of human monocytes to differentiate into mature DCs and their ability to induce an antiviral immune response was investigated in HIV-infected patients. In healthy subjects, monocytes differentiate into CD1a+ DCs in the presence of granulocyte macrophage colony-stimulating factor and interleukin (IL)-4 and matured in the presence of lipopolysaccharide. Here, we found that in 30% and 45% of HIV-infected white and African subjects, respectively, monocytes gave rise to a homogeneous CD1a* DC population. In the patients who gave rise only to the CD1a* DCs, this population spontaneously produced IL-10 but not IL-12, and induced a T helper 2-like immune response when cultured with human T cells isolated from cord blood mononuclear cells. In patients with monocytes differentiated into CD1a* DCs, a high percentage of HIV-specific CD4 T cells producing IL-4 were seen in the peripheral blood. Furthermore, differentiation of monocytes into DCs with CD1a* phenotype correlated with low CD4 T-cell counts and high viral loads in HIV-infected subjects. These results suggest that the differentiation of monocytes into CD1a* DCs may be a phenotypic marker associated with progression of the disease.     

Virtual colon dissection with CT colonography compared with axial interpretation and conventional colonoscopy: preliminary results

OBJECTIVE: The aim of this study was to determine whether a new virtual colon dissection 3D visualization technique for CT colonography has a shorter analysis time and better sensitivity for detection of colonic polyps than interpretation of axial CT images. SUBJECTS AND METHODS. CT colonography was performed in 22 patients using 4-MDCT followed by conventional colonoscopy on the same day. The CT colonography data sets were analyzed by virtual colon dissection, which virtually bisects and unfolds the colon along its longitudinal axis to inspect the inner colonic surface for polyps. The same CT data sets were independently evaluated using axial interpretation. All data sets were independently interpreted by two radiologists in a blinded manner. RESULTS: Conventional colonoscopy revealed 31 colonic lesions in 20 patients. Twenty two of the lesions were smaller than 10 mm; nine were 10 mm or larger. Two of the original 22 patients were excluded, one because of residual stool and fluid and the other because of an impassable stenosing rectal wall cancer. For virtual colon dissection, the per-lesion sensitivity was 42% for observer 1 and 68% for observer 2; for axial interpretation, the respective sensitivities were 48% and 61%. For polyps 10 mm or larger, the respective sensitivities were 67% and 89% for virtual colon dissection and 89% and 100% for axial interpretation. The average time for reconstruction and analysis of virtual colon dissection was 36.8 min versus 29.2 min for axial images. Virtual colon dissection was feasible in both the supine and the prone positions in 45.5% of colonic segments, in either the supine or the prone position in 24.5%, and in neither position in 30% of segments. CONCLUSION: Although virtual colon dissection may facilitate detection of colonic polyps in isolated cases, its detection rate is not superior to axial interpretation, which is mainly attributable to failed rendering of insufficiently distended colonic segments or regions with residual feces. Virtual colon dissection is also the more time-consuming of the two procedures. With further improvement of path-finding and image segmentation, however, virtual colon dissection has the potential to be a useful interpretation tool for CT colonography.     

Cost analysis of blood purification in intensive care units: continuous versus intermittent hemodiafiltration

BACKGROUND: We implemented a program for continuous renal replacement therapies (CRRT) in intensive care units (ICU) based on the cooperative work of dialysis and ICU personnel. Our aim was to report the main details of this program and compare its cost with that of intermittent hemodiafiltration (IHDF). METHODS: The study referred to 181 ICU patients with renal failure. We considered the costs of both technical devices and assisting personnel. CRRT was performed as continuous veno-venous hemodiafiltration (CVVHDF) (24 hr daily); dialysis and ICU nurses shared surveillance. Only dialysis nurses performed IHDF (as acetate-free biofiltration, 4 hr daily) in the ICU. RESULTS: The daily cost of CRRT was Euro 276.70; of which 79% was for devices and 21% was for human resources. Nurse surveillance required 141 min per day, ICU nurses supplied 55% (77 min) and dialysis nurses 45% (64 min). On average, CRRT surveillance required less than 1 min/nurse/hr for both dialysis and ICU nurses. The daily cost of 4-hr IHDF sessions of was Euro 247.83, of which 44% was for technical devices and 56% was for human resources. CONCLUSIONS: The cooperation between dialysis and ICUs improved the use of human resources and allowed us to supply CRRT to all critically ill patients with acute renal failure. The expenditure for CRRT was 12% higher than that for IHDF, due to the cost of technical devices.     

Nonmetastatic osteosarcoma of the extremity with pathologic fracture at presentation: local and systemic control by amputation or limb salvage after preoperative chemotherapy

To determine whether a pathologic fracture in osteosarcoma of long bones has prognostic importance, and limb salvage can be safely performed in such cases, we reviewed the surgical treatment and oncologic results in 46 patients with nonmetastatic osteosarcoma of the extremity and pathologic fracture at presentation who had been treated in our Institution with neoadjuvant chemotherapy, between 1983 and 1999. Neoadjuvant chemotherapy was given according to 6 consecutive protocols. Surgery consisted of limb salvage (34 patients), amputation (11 patients) and rotationplasty (1 patient). The average follow-up was 11 (3-20) years. 28 patients remained continuously disease-free, 17 patients relapsed and 1 died of chemotherapy-related toxicity. Despite the high rate of limb salvage, only 2 local failures occurred, 1 after amputation and 1 after limb salvage. The 5-year disease-free survival and overall survival rates were 59% and 65%, respectively, with no differences between amputated and resected patients. These results are similar to those obtained in 689 contemporary patients having an osteosarcoma without a pathologic fracture treated in our Institution, and using the same protocols for chemotherapy. We conclude that with neoadjuvant chemotherapy, osteosarcoma patients presenting with a pathologic fracture can be surgically treated like those with no fracture, and that limb salvage procedures do not increase the risk of local recurrence or death of these patients.