Binary particle swarm optimization as a detection tool for influential subsets in linear regression.

An influential observation is any point that has a huge effect on the coefficients of a regression line fitting the data. The presence of such observations in the data set reduces the sensitivity and validity of the statistical analysis. In the literature there are many methods used for identifying influential observations. However, many of those methods are highly influenced by masking and swamping effects and require distributional assumptions. Especially in the presence of influential subsets most of these methods are insufficient to detect these observations. This study aims to develop a new diagnostic tool for identifying influential observations using the meta-heuristic binary particle swarm optimization algorithm. This proposed approach does not require any distributional assumptions and also not affected by masking and swamping effects as the known methods. The performance of the proposed method is analyzed via simulations and real data set applications.

Temporal Trends in the Epidemiology of HIV in Turkey.

OBJECTIVE: The aim of this study was to analyze the temporal trends of HIV epidemiology in Turkey from 2011 to 2016. METHODS: Thirty-four teams from 28 centers at 17 different cities participated in this retrospective study. Participating centers were asked to complete a structured form containing questions about epidemiologic, demographic and clinical characteristics of patients presented with new HIV diagnosis between 2011 and 2016. Demographic data from all centers (complete or partial) were included in the analyses. For the cascade of care analysis, 15 centers that provided full data from 2011 to 2016 were included. Overall and annual distributions of the data were calculated as percentages and the Chi square test was used to determine temporal changes. RESULTS: A total of 2,953 patients between 2011 and 2016 were included. Overall male to female ratio was 5:1 with a significant increase in the number of male cases from 2011 to 2016 (p<0.001). The highest prevalence was among those aged 25-34 years followed by the 35-44 age bracket. The most common reason for HIV testing was illness (35%). While the frequency of sex among men who have sex with men increased from 16% to 30.6% (p<0.001) over the study period, heterosexual intercourse (53%) was found to be the most common transmission route. Overall, 29% of the cases presented with a CD4 count of >500 cells/mm3 while 46.7% presented with a CD4 T cell count of <350 cells/mm3. Among newly diagnosed cases, 79% were retained in care, and all such cases initiated ART with 73% achieving viral suppression after six months of antiretroviral therapy. CONCLUSION: The epidemiologic profile of HIV infected individuals is changing rapidly in Turkey with an increasing trend in the number of newly diagnosed people disclosing themselves as MSM. New diagnoses were mostly at a young age. The late diagnosis was found to be a challenging issue. Despite the unavailability of data for the first 90, Turkey is close to the last two steps of 90-90-90 targets.

Integrase Strand Transfer Inhibitors (INSTIs) Resistance Mutations in HIV-1 Infected Turkish Patients.

OBJECTIVES: Integrase strand transfer inhibitor (INSTI) is a new class of antiretroviral (ARV) drugs designed to block the action of the integrase viral enzyme, which is responsible for insertation of the HIV-1 genome into the host DNA. The aim of this study was to evaluate for the first time INSTI resistance mutations in Turkish patients. METHODS: This study was conducted in Turkey, between April 2013 and April 2015 using 169 HIV-1-infected patients (78 ARV naive patients and 91 ARV-experienced patients). Laboratory and clinical characteristics of ARV naive and ARV-experienced patients were as follows: gender (M/F): 71/7 and 80/11, median age: 38 and 38.4; median CD4(+) T-cell: 236 and 216 cells/mm(3), median HIV-1 RNA: 4.95+E5 and 1.08E+6 copies/ml. Population-based seqeunces of the reverse transcriptase, protease, and integrase domains of the HIV-1 pol gene were used to detect HIV-1 drug resistance mutations. RESULT: INSTI resistance mutations were not found in recently diagnosed HIV-1-infected patients. However, ARV-experienced patients had major resistance mutations associated with raltegravir and elvitegravir; the following results were generated:F121Y, Y143R, Q148R and E157Q (6/91 - 6.6%). CONCLUSIONS: The prevalence of INSTI resistant mutations in ART-experienced patients suggested that resistance testing must be incorporated as an integral part of HIV management with INSTI therapies.

The course of spinal tuberculosis (Pott disease): results of the multinational, multicentre Backbone-2 study.

We aimed to describe clinical, laboratory, diagnostic and therapeutic features of spinal tuberculosis (ST), also known as Pott disease. A total of 314 patients with ST from 35 centres in Turkey, Egypt, Albania and Greece were included. Median duration from initial symptoms to the time of diagnosis was 78 days. The most common complications presented before diagnosis were abscesses (69%), neurologic deficits (40%), spinal instability (21%) and spinal deformity (16%). Lumbar (56%), thoracic (49%) and thoracolumbar (13%) vertebrae were the most commonly involved sites of infection. Although 51% of the patients had multiple levels of vertebral involvement, 8% had noncontiguous involvement of multiple vertebral bodies. The causative agent was identified in 41% of cases. Histopathologic examination was performed in 200 patients (64%), and 74% were consistent with tuberculosis. Medical treatment alone was implemented in 103 patients (33%), while 211 patients (67%) underwent diagnostic and/or therapeutic surgical intervention. Ten percent of the patients required more than one surgical intervention. Mortality occurred in 7 patients (2%), and 77 (25%) developed sequelae. The distribution of the posttreatment sequelae were as follows: 11% kyphosis, 6% Gibbus deformity, 5% scoliosis, 5% paraparesis, 5% paraplegia and 4% loss of sensation. Older age, presence of neurologic deficit and spinal deformity were predictors of unfavourable outcome. ST results in significant morbidity as a result of its insidious course and delayed diagnosis because of diagnostic and therapeutic challenges. ST should be considered in the differential diagnosis of patients with vertebral osteomyelitis, especially in tuberculosis-endemic regions. Early establishment of definitive aetiologic diagnosis and appropriate treatment are of paramount importance to prevent development of sequelae.

Antitumor effects of Origanum acutidens extracts on human breast cancer.

PURPOSE: There has been a long-standing interest in the identification of medicinal plants and derived natural products for developing anticancer agents. This work aimed at investigating the antiprolipherative properties of Origanum acutidens (OA) on breast cancer. METHODS: OA water extracts were studied for cytotoxicity against the breast cancer cell lines MCF-7, MDA-MB-468 and MDA-MB-231. In vitro apoptosis studies of these cancer cell lines were performed by annexin V staining in flow cytometry analyses. Immunohistochemistry studies for Ki-67 and caspase-7 of tumor tissue sections of dimethylbenzanthracene (DMBA) -induced mammary cancer in rats were also performed. TUNEL assay was used to detect apoptotic cells of tumor tissue. In vivo anticancer activity testing was carried out by inhibiting the growth of DMBA-induced mammary cancer in rats. RESULTS: OA showed cytotoxicity on all 3 cancer cell lines. Annexin-positive cells level in OA-treated cell lines were significantly higher compared with untreated control cells (p=0.002). The expressions of caspase-7 protein and TUNEL-positive cells were much higher for the rats treated by OA, compared with the untreated control group (p<0.05). The expressions of the Ki-67 decreased in the treated groups compared with the control group (p<0.05). In vivo studies showed that the mean tumor volume inhibition ratio in OA-treated group was 41 % compared with the untreated rats (p<0.05). CONCLUSION: These results indicate that OA has antitumor activity against breast cancer cell lines.

Inappropriate antimicrobial use in Turkish pediatric hospitals: a multicenter point prevalence survey.

OBJECTIVES: Although well-defined principles of rational antimicrobial use are available, inappropriate prescribing patterns are reported worldwide. Accurate information on the usage of antimicrobials, including factors associated with and influencing their use, is valuable for improving the quality of prescription practices. METHODS: In this cross-sectional point prevalence survey, data on patients hospitalized in 12 different children's hospitals were collected on a single day. Appropriateness of prescription was compared between the types of antimicrobials prescribed, indications, wards, and presence of/consultation with an infectious disease physician (IDP). RESULTS: A total 711 of 1302 (54.6%) patients evaluated were receiving one or more antimicrobial drugs. The antimicrobial prescription rate was highest in pediatric intensive care (75.7%) and lowest in the surgery wards (37.0%). Of the 711 patients receiving antimicrobials, 332 patients (46.7%) were found to be receiving at least one inappropriately prescribed drug. Inappropriate use was most frequent in surgery wards (80.2%), while it was less common in oncology wards (31.8%; p<0.001). Respiratory tract infection was the most common indication for antimicrobial use (29.4%). Inappropriate use was more common in deep-seated infections (54.7%) and respiratory infections (56.5%). Fluoroquinolones were used inappropriately more than any other drugs (81.8%, p=0.021). Consultation with an IDP appears to increase appropriate antimicrobial use (p=0.008). CONCLUSIONS: Inappropriate antimicrobial use remains a common problem in Turkish pediatric hospitals. Consultation with an IDP and prescribing antimicrobial drugs according to microbiological test results could decrease the inappropriate use of antimicrobials.

Bone marrow infection caused by Mycobacterium avium complex in a patient with systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a disease with wide range of signs and symptoms. SLE patients have increased infective diathesis, and infections are a very important cause of death in these patients. Infections can sometimes mimic the signs and symptoms of SLE. Thus, it is important to recognize that infection can induce a lupus flare-up or can be difficult to distinguish from a lupus flare-up. We describe a 36-year-old female patient with SLE, who presented with skin lesions and pancytopenia, and clinical manifestations similar to a flare-up of SLE. Bone marrow examination revealed infection with Mycobacterium avium complex (MAC). The patient had no history or clinical evidence of pulmonary involvement. This patient is the first case of invasive bone marrow MAC infection in SLE. With this unique case, we would like to emphasize that SLE patients can also be infected by non-tuberculous mycobacteria, and that bone marrow examination for tuberculosis as well as for non-tuberculosis mycobacteria should be considered in SLE patients with refractory pancytopenia.

A rare case of HSV-2 encephalitis.

Herpes simplex viruses (HSV), and especially HSV-1, are the most common cause of acute, sporadic viral encephalitis. HSV-2 is an uncommon cause of encephalitis. We report a rare case of HSV-2 encephalitis that was free of genital lesions. In terms of the patient's case history, she had a Cesarean section four months before, herpes labialis 30 days before, varicella zoster 20 days before. We discuss the possibility that postpartum stress may be one of the factors in this case.

Human fascioliasis.

Fasciola hepatica, a zoonotic liver fluke, can also cause disease in humans. Common symptoms are epigastric pain, upper abdominal pain and malaise. Fever and arthralgia are common in acute fascioliasis. Eosinophilia is the predominant laboratory finding, especially in patients with the acute form of the disease. Diagnosis and treatment is not easy, as physicians rarely encounter this disease, and effective drugs are not available in many countries. Human fascioliasis may be underestimated. Patients with eosinophilia and abdominal pain should be evaluated for F. hepatica infestation by parasitological, radiological and serological tests.

First confirmed case of vancomycin-resistant Enterococcus faecium meningitis in Turkey: case report and literature review.

Vancomycin-resistant enterococci are unusual etiologic agents of bacterial meningitis and pose significant therapeutic difficulties. We report the first confirmed case of nosocomial vancomycin-resistant Enterococcus faecium meningitis in Turkey. The patient was treated with chloramphenicol and cerebrospinal fluid cultures became negative, but clinical success was not achieved. We also review the previously reported cases of vancomycin-resistant Enterococcus faecium meningitis.