Reparative dentin formation using stem cell therapy versus calcium hydroxide in direct pulp capping: an animal study

Abstract Direct pulp capping process is a therapeutic method aimed at maintenance of pulp vitality and health by using a biocompatible material placed directly over the exposed pulp. The aim of this study was to evaluate and compare the effect of direct pulp capping procedures by dental pulp stem cells (DPSCs) or calcium hydroxide on dentin tissue formation. Three mongrel dogs were used as experimental model. Two access cavities were prepared in the right and left mandibular fourth premolars in all dogs to expose and extirpate the pulp tissues which were processed in the lab to obtain a single-cell suspensions. The isolated cells were cultures in odontogenic medium for subsequent differentiation. The maxillary teeth (3 incisors and one canine) of the corresponding dog number were subjected to class V cavities to expose their pulps which were assigned into 2 groups of 12 teeth each ( group I - pulp capping with calcium hydroxide) and (group II - pulp capping with dental stem cells DPSCs). The operated teeth were collected after 3 months and processed for histological and electron microscopic examinations. Specimens were subjected to elemental analysis of calcium and phosphorus. EDX elemental analysis revealed significant differences in the calcium and phosphorous wt, % in the reparative dentin of calcium hydroxide treated group which confirmed histologically. Direct pulp capping by DPSCs has shown promising generative potential for regaining normal dentin.

Resumo O processo de capeamento pulpar direto é um método terapêutico que visa a manutenção da vitalidade e saúde da polpa, usando um material biocompatível colocado diretamente sobre a polpa exposta. O objetivo deste estudo foi avaliar e comparar o efeito do capeamento pulpar direto usando células-tronco da polpa dentária (CTPDs) ou hidróxido de cálcio sobre o tecido da dentina formação. Três cães sem raça definida foram utilizados como modelo experimental. Duas cavidades de acesso foram preparados nos quartos pré-molares inferiores direito e esquerdo em todos os cães para expor e extirpar os tecidos pulpares que foram processados ​​em laboratório para obter suspensões de uma célula única. As células isoladas foram cultivadas em meio odontogênico para posterior diferenciação. Os dentes superiores (3 incisivos e um canino) do respectivo cão foram submetidos ao preparo de cavidades classe V para expor suas polpas, as quais foram atribuídas a 2 grupos de 12 dentes cada (grupo I - capeamento pulpar com hidróxido de cálcio) e (grupo II - capeamento pulpar com CTPDs). Os dentes operados foram extraídos após 3 meses e processado para exames histológicos e por microscopia eletrônica de varredura. Os espécimes foram submetidos a análises elementares de cálcio e fósforo. Análise elementar por EDX revelaram diferenças significativas no peso de cálcio e fósforo, % na massa reparadora dentina do grupo tratado com hidróxido de cálcio, o que foi confirmado histologicamente. O capeamento pulpar com CTPDs mostrou potencial promissor para recuperar a dentina normal.

Increased frequency of CD4 + CD25 + FoxP3 + circulating regulatory T cells [Treg] in tuberculous patients

CD4 + CD25 + FoxP3 + circulating regulatory T cells [Treg] play a fundamental role in the control of immune responses by down-regulating the function of effector CD4 + or CDS + T cells. Active suppression by Treg might be important in controlling immune responses against Mycobacterium tuberculosis [Mtb]. This study was conducted to evaluate the cellular immune response to Mtb, by evaluation of Treg cells in peripheral blood mononuclear cells [PBMCs] from patients with active pulmonary tuberculosis [PTB], patients with tuberculous pleurisy [TP] and healthy positive PPD persons as control, then evaluation after 6 months of anti-TB therapy, also evaluation of Treg cells in pleural fluid mononuclear cells [PFMCs] from patients with tuberculous pleurisy [TP]. We compared the frequency of CD4 + CD25 + FoxP3 + circulating regulatory T cells [Treg] in 20 patients with active pulmonary TB [PTB], 15 tuberculous pleurisy [TP] and 20 control latent tuberculosis. Treg frequencies in peripheral blood were significantly higher in patients with PTB and TP than in the control group [p < 0.001]. Treg frequencies were significantly higher in pleural effusions than in peripheral blood in the same group [p < 0.001]. Treg frequencies in peripheral blood were significantly decreased after 6 months of anti-TB treatment [p < 0.001]. Immune regulatory mechanisms may limit the immunopathologic condition of infection with M. tuberculosis and suppress cellular immune responses in the host. We investigated the CD4 + CD25 + FoxP3 + circulating regulatory T cells [Treg] in patients with pulmonary tuberculosis, tuberculous pleurisy and latent TB, and the frequencies of CD4 + CD25 + FoxP3 + T-cells after anti-TB therapy. MTB infection is associated with an increase in the frequency of CD4 + CD25 + FoxP3 + Treg in the blood of PTB and TP, in the pleural fluid of TP, decrease in the frequency after anti-TB therapy

Role of DNase in combination with quinolones on stentrophomonas maltophila biofilm

Stentrophomonas maltophila [S. maltophila] biofilm plays a crucial role in its resistance to antibiotics. Extracellular DNA found to be an essential component of biofilm of different Gram positive and Gram negative bacteria. Its role in S. maltophila biofilm is not well established. This work assessed the role of destruction of extracellular DNA of S. maltophila biofilms in enhancing the antimicrobial effect of the used levofloxacin or ciprofloxacin. This study enrolled twenty three isolates of S. maltophila in which biofilm production and the presence of extracelular DNA in it were tested. The effect of two quinolone antibiotics [ciprofloxacin and levofloxacin] and DNAase each alone and in combination together on biofilm production were assessed on biofilm production and viable count. Our results showed that combined use of DNase with either ciprofloxacin or levofloxacin caused significant reduction of both biomass and viable count. In conclusion, the addition of DNase to quinolones boosts the antibiotic efficacy against S. maltophila biofilm

Early detection of neonatal sepsis, dilemma of diagnosis

Background and objectives: Accurate identification of neonatal sepsis is an increasing problem facing neonatologists due to non specific clinical signs with no existing single reliable marker of infection. Molecular assays for the detection of bacterial DNA in the blood represent possible diagnostic tools for early identification of bacterial causes. Procalcitonin [PCT] is a promising marker distinguishing between infection and inflammation which cannot be differentiated by acute phase proteins as C-reactive protein [CRP]. The aim of the study was to compare results of blood cultures with eubacterial PCR, PCT and CRP as early markers of neonatal sepsis

Subjects and methods: In this study, neonates with clinically suspected sepsis admitted to neonatal intensive care unit [NICU] in Mansoura University Children Hospital were included. Based on blood culture positive results, they were divided into 2 groups: proven sepsis and clinical sepsis. Comparing the 2 groups, sensitivity and specificity for, PCR, PCT and CRP were evaluated. Using receiver operating characteristic [ROC] curves, threshold value for both PCT and CRP were estimated

Results: Out of 141 neonates with clinically suspected sepsis, 56 (39.7%) were confirmed as proven sepsis. Compared to blood culture, the diagnosis of bacterial proven sepsis by PCR revealed 100 % sensitivity and 93% specificity. This study revealed that PCT >6.5 ng/ml had 83.9% sensitivity and 98.8% specificity, whereas CRP >3.5 mg/dl had 83.9%, sensitivity and 8l.2%specificity for diagnosing sepsis

Conclusion: This study confirms the value of PCR and PCT as rapid diagnostic tools for early detection of neonatal sepsis?

Gene polymorphism analysis in the epidemiological typing of hospital acquired methicillin-resistant staphylococcus aureus isolates

Background and objectives: typing of Meticillin-resistant Staphylococcus aureus [MRSA] is of great importance for detection of the relatedness of isolate. Both phenotypic and genotypic markers can be employed to type MRSA strains. The spa gene encoding protein A and the CoA gene encoding coagulase enzyme contain highly polymorphic repeat units. These repeats allowed for differentiation between MRSA isolates that are heterogeneous in respect to these regions using polymerase chain reaction - restriction fragment length polymorphism [PCR - RFLP] assay. This study aimed to address the competence of various typing methods [antibi typing, coa gene typing and spa gene typing] in discriminating MRSA isolates and to assess the concordance between the used typing methods

Material and Methods: this study included, 61 nosocomial MRSA isolates collected from different clinical wards of Mansoura University Hospitals between December 2009 and September 2010. They were analyzed by antibiotic resistance profile and PCR - RFLP of both CoA and spa genes after Alu- I and Rsa -I restriction enzymes digestion respectively. The discrimination index [D] and concordance were calculated

Results: the power of discrimination among MRSA isolates as estimated by the discrimination index increased orderly from antibi typing [D = 0.69], spa gene typing [D = 0.74] to CoA gene typing [D = 0.82] yielding 8, 5 and 6 types respectively. Combination of the 3 typing methods offered the highest D of 0.98. Coa gene typing was more concordant with spa gene typing, while the concordance between antibi typing and each of Coa and spa typing was the same

Conclusion: we concluded that, CoA typing demonstrated the most effective discrimination of MRSA isolates, while grouping of isolates based on combining the 3 typing methods provided the highest discrimination. So, CoA and spa genetic typing methods could be used in routine epidemiological surveillance in association with antibi typing as daily screening test which is very beneficial to develop efficient infection control measures in hospitals

Botulinum toxin: could it be an effective treatment for chronic tension - type headache?

Several clinical trials suggest that botulinum toxin type-A [BTX-A] may be an effective treatment options for patients with chronic tension-type headache; however, controversy remains as how botulinum toxin optimally should be used for treating headache and which patients profile that fit for this treatment. The objective of this study was to evaluate the efficacy and tolerability of BTX-A for the prophylactic treatment of chronic tension-type headache in Egyptian patients. This was a randomized, single-blind, placebo-controlled study of botulinum toxin type-A for the treatment of patients aged 25 to 50 years old with chronic tension-type headache. Following a 30-day screening; headache parameters and severity assessed by the standard visual analogue scale [VAS] and the 25-item Henry Ford Hospital Headache Disability Inventory [HDI] were recorded as a baseline. Then, injection was done with either BTX-A or with saline by a combination of two methods for detecting injection sites [the fixed-site approach and follow-the-pain approach]. Our study showed significant improvement after one month of BTX-A injection regarding headache days/month, severity measured by VAS and HDI in headache severity. There was significant reduction of prophylactic medications, and there were minor complications but these reversed spontaneously without further treatment. BTX-A was an effective and well-tolerated prophylactic treatment in Egyptian patients with chronic tension-type headache

Dementia: clinical-neurobiochemical correlations

This study aimed at correlating the cognitive impairments and their neuropathological basis in AD and VaD with the neurobiochemical changes in brain tissues using proton magnetic resonance spectroscopy [[1]H-MRS]. Twenty patients diagnosed as having dementia [10 with AD, and 10 with VaD] were included in this study and compared with 10 normal control subjects. Dementia patients were selected using DSM IVR, HIS, ADDTC and NINCDS. Patients were submitted to the following battery of investigations: Thorough clinical examination, routine Laboratory investigations, and various neuropsychological scales [MMSE, CAMCOG, Blessed DR scale, and Hamilton depression scale]. Brain MRI and MRS were done for all patients and control subjects. Cognitive impairment was significantly more prominent in AD patients compared to VaD patients. The most consistent neurochemical differences between demented patients and normal control subjects were significant reductions of the NAA/Cr and NAA/MI ratios at PCG and NAA/Cr ratio at Lt STG, and elevation of MI/Cr ratio at PCG, while the most consistent differences between AD and VaD patients were significant reductions of the NAA/Cr and NAA/MI ratios at PCG, Lt STG and elevated MI/Cr ratio at PCG in patients with A.D. Significant correlation was observed between the reduced NAA/Cr, NAA/MI and elevated MI/Cr ratio at PCG and changes in various neuropsychological variables studied in AD patients. Clinical neuropsychological testing is a fairly good tool for differentiation of the types of dementia [AD versus VaD]. However the neurochemical changes in brain tissues measured using [[1]H-MRS] are useful not only in distinguishing between dementia of the Alzheimer's type and vascular dementia but also explaining their neuropathological background

Central nervous system involvement in chronic inflammatory demyelinating polyradiculoneuropathy: a clinical, neurophysiological and radiological study

The frequency of the association between CIDP and CNS lesions is probably underestimated. To assess the frequency of CNS involvement in CIDP patients, and to study the characteristics of this possible association. Forty patients [20 males, and 20 females] aged between 19 and 50 years [mean 33.12 +/- 9.3 years] fulfilling the clinical, neurophysiological and CSF criteria of INCAT for the diagnosis of CIDP were submitted to complete general and neurological assessment, laboratory investigations, CSF analysis, neurophysiological evaluation [NC studies, evoked potentials [VEPs, BAEPs, SSEPs]], and MRI brain and spinal cord. Clinical evidences of CNS involvement were recorded in 12 patients [30%] of CIDP patients, abnormally delayed VEPs latencies were recorded in 16 patients [40%], abnormal BAEP latencies in 12 patients [30%], abnormal SSEP latencies in 22 patients [55%], and abnormal latencies in more than one modality in 13 patients [32.5%], MRIs brain and spinal cord were abnormal in 10 patients [25%]. CIDP patients with clinical and/or radiological evidences of CNS involvement had a significantly younger age of disease onset, more frequent relapsing-remitting pattern of the disease course, more prolonged disease duration, and less favorable response to therapy than those without evidences of CNS involvement. CIDP patients with delayed evoked potentials' latencies and/or MRI demyelinating lesions were more frequent in CIDP patients with clinical evidences of CNS involvement. Moreover, MRI lesions were more frequent in those having abnormal visual evoked potential responses. Finally, there was a percentage of CIPD patients who showed a subclinical central neurophysiological and/or radiological abnormalities. CIDP is frequently associated with various clinical, neurophysiological and radiological evidences of CNS involvement. MRI and evoked potentials are useful non-invasive techniques for demonstrating this association