pH-Induced conformational isomerization of leghemoglobin from Arachis hypogea.

The pH dependence of proteins is related to the thermodynamic stability and electrostatic interactions in the native state of a protein. Here we report the pH-induced conformational transition of the heme protein leghemoglobin (Lb) isolated from root nodules of the leguminous plant Arachis hypogea. Unlike the other heme proteins myoglobin, hemoglobin, and cytochrome c, the structural characteristics and interactions of Lb is almost unknown, though its functional importance is already established since it binds oxygen to maintain the environment for N2 fixation. We investigated pH-induced unfolding of this protein and identified a number of conformational isomers using multiple fluorescence observables as a function of pH titration. We have characterized the acid- and base-induced conformational transitions among the structural states over the pH range 2-11. Depending on the solution conditions, Lb can exist in one of three phases: pH 2, 3, 4; pH 5, 6, 7; pH 8, 9, 10. The secondary structure as revealed by CD spectroscopy indicated the maximum percentage of α-helix to be present at pH 7, where the structure of Lb is also most rigid according to fluorescence anisotropy experiments. The fluorescence lifetime of tryptophan was observed to be maximum at pH 10 and minimum at pH 6, suggesting unfolding transitions of Lb. Thus, alteration of the microenvironment of the globin moiety during pH transition ultimately leads to the conformational change of this monomeric protein Lb.

The effects of systemic isotretinoin and antibiotic therapy on the microbial floras in patients with acne vulgaris.

BACKGROUND: Although there are several studies about the alteration in skin flora, limited number of reports about changes in the microbial contents and their resistance profile of other body sites in patients treated with isotretinoin for acne vulgaris. OBJECTIVES: The aim of this study was to investigate the effects of systemic isotretinoin and antibiotic therapy on the microbial floras of oropharynx, nose and feces in acne patients. METHODS: Treatment groups of isotretinoin and antibiotics consisting of 20 and 15 patients, respectively were included. Microbiological culture samples were taken at baseline and once a month during 4-6 months of treatment period. RESULTS: Difference in microbial flora throughout the treatment period was detected at least among one of all culture samples of 15 (75%) and 5 (33%) patients in isotretinoin and antibiotic groups. There was statistically significant difference between two groups in means of alteration of the microbial flora (P = 0.013). The difference was definitely observed among nasal cultures (65%) in isotretinoin group and fecal cultures (20%) in the other. Staphylococcus aureus colonization was prominent in the microbial floras of nose and oropharynx and 2 of 14 nasal isolates were detected to be methicilline resistant while Escherichia coli with extended spectrum beta lactamase activity was detected in fecal floras of patients in isotretinoin group. CONCLUSIONS: Systemic isotretinoin and antibiotic treatments in acne patients precisely caused variations in the microbial floras of several sites of the body, while isotretinoin was commonly more responsible than antibiotics. Knowing that alterations in the microbial colonization of the flora regions may preceede infectious disease and bacterial resistance, treatment options and follow-up procedures in acne vulgaris should be carefully determined to reduce the risk of destruction of the microbial flora.

Development of an online tool for public health: the European Public Health Law Network.

BACKGROUND: The European Public Health Law Network was established in 2007 as part of the European Union (EU) co-funded Public Health Law Flu project. The aims of the website consisted of designing an interactive network of specialist information and encouraging an exchange of expertise amongst members. The website sought to appeal to academics, public health professionals and lawyers. METHODS: The Public Health Law Flu project team designed and managed the website. Registered network members were recruited through publicity, advertising and word of mouth. Details of the network were sent to health organizations and universities throughout Europe. Corresponding website links attracted many new visitors. Publications, news, events and a pandemic glossary became popular features on the site. Although the website initially focused only on pandemic diseases it has grown into a multidisciplinary website covering a range of public health law topics. RESULTS: The network contains over 700 publications divided into 28 public health law categories. News, events, front page content, legislation and the francophone section are updated on a regular basis. Since 2007 the website has received over 15,000 views from 156 countries. Newsletter subscribers have risen to 304. There are now 723 followers on the associated Twitter site. CONCLUSION: The European Public Health Law Network has been a successful and innovative site in the area of public health law. Interest in the site continues to grow. Future funding can contribute to a bigger site with interactive features and pages in a wider variety of languages to attract a wider global audience.

[Early melanoma as opposed to a benign nevus, nevus-associated melanoma, or halo nevus with regression?]. / Frühes Melanom neben einem benignen Nävus, nävusassoziiertes Melanom oder regressiver Nävus?

A 43-year-old woman, in whom a melanoma associated with a melanocytic nevus had been removed 2 years previously, came for a follow-up examination presenting with two light brown to medium brown maculae measuring approximately 7x5 mm with a flat papular center. One of the lesions was surrounded by a large white halo about 2 mm in size. The differential diagnosis on clinical grounds included a halo nevus with a second common nevus, a nevus with regression, and a melanoma associated with a nevus. Under the dermatoscope, an unremarkable homogeneous/reticular pattern could be seen and in one portion hallmarks of regression, namely gray tones and distinct gray-black dots. The diagnosis based on histopathological analysis was that of an atypical congenital nevus with regression.

Traumatic lingual ulcer in a child: Riga-Fede disease.

Riga-Fede disease RFD is an extremely rare, benign inflammatory disorder characterized by reactive, traumatic ulceration of the oral mucosa especially located on the tongue. It is most commonly associated with natal or neonatal teeth in newborns. Mucosal lesions are often caused by repetitive traumatic damage due to backward and forward motions of the tongue over the lower incisors. Failure to diagnose and treat these lesions properly may result in inadequate food intake, growth retardation and permanent lingual deformity. We report a 15-month-old healthy infant with tongue ulcer diagnosed as RFD based on history and clinical features.

Is there any relationship between serum and urine neopterin and serum interferon-gamma levels in the activity of Behcet's disease?

BACKGROUND: Behcet's disease (BD) is a chronic, inflammatory, multisystem vasculitic disorder. There is no reliable laboratory marker that indicates disease activity. Neopterin is an immunological marker of cellular immune activation, which is secreted by monocytes/macrophages as a result of interferon-gamma (IFN-gamma) secretion by activated T lymphocytes. OBJECTIVE: We aimed to investigate serum and urine neopterin levels in BD patients. METHODS: Forty-five patients who were diagnosed according to the criteria of the International Study Group for BD and 45 age- and sex-matched healthy controls were enrolled in the study. Disease activity was considered by clinical findings. Serum and urine neopterin levels and serum IFN-gamma levels were measured. RESULTS: The mean values of serum and urine neopterin levels were 12.68 +/- 4.87 nmol/L and 167.53 +/- 148.73 micromol/mol creatinine, respectively, in BD patients (P = 0.000 and P = 0.008, respectively), which were statistically significantly different from the control group. However, there was no significant statistical difference between serum and urine neopterin levels of the clinically active and inactive patients. It was also found that the mean value of serum IFN-gamma levels was higher in healthy controls than in BD patients (P = 0.000). CONCLUSIONS: We conclude that serum and urinary neopterin measurement can not be used as a reliable laboratory marker as the BD patients' serum and urinary neopterin levels do not increase in the active stage even though these levels increase when compared to healthy controls.

Evaluation of activatory and inhibitory natural killer cell receptors in non-segmental vitiligo: a flow cytometric study.

BACKGROUND: Recent observations established the role of altered cellular immunity and autoimmune hypothesis in the pathogenesis of vitiligo. There have been several reports discussing T-cell and natural killer (NK) cell populations, but NK cell receptors were not evaluated in vitiligo. OBJECTIVE: The purpose of this investigation was to assess the role of T and NK cells as well as activatory and inhibitory NK cell receptor alterations in the pathogenesis of vitiligo and whether any aberrations were correlated with clinical findings of the disease. PATIENTS/METHODS: Fifty-three patients with non-segmental vitiligo and 45 age- and sex-matched healthy controls were enrolled in the study. The percentages of lymphocytes, granulocytes, monocytes and CD3, CD4, CD8, CD14, CD16, CD56, CD45, CD45RA, CD54RO, CD28, CD80, CD94, CD158a, KIR3DL-1 receptors as well as CD94, CD158a, KIR3DL-1 receptors on CD16(+) cells were detected by using flow cytometry. The patient and control groups were compared in terms of the results of flow cytometric analysis, and the results were assessed regarding the type and activity of vitiligo. RESULTS: The percentages of CD16(+)CD56(+), CD3(+)CD16(+)CD56(+), CD8(+) and CD45RO(+) cells were significantly increased in vitiligo group compared with the controls. No difference was detected between the patients and control groups in percentages of CD3(+), CD4(+), CD3(-)CD16(+)CD56(+), CD28(+), CD45(+), CD45RA(+), CD94(+), CD158a(+) and KIR3DL-1(+) cells. The percentage of CD16(+)CD158a(+) cells was significantly decreased in a randomized selected group of vitiligo patients. There were no differences in percentage expression of studied cell surface antigens between patients in the active or stable period. CD3(+) cells were significantly increased in generalized form, and CD45RO(+) cells were significantly increased in acral/acrofacial form when compared with the other types of vitiligo. CONCLUSIONS: These results indicate further evidence for T and NK cell abnormalities in non-segmental vitiligo. The present data show that NK cell activation may be responsible in the pathogenesis of vitiligo in conformity with decreased inhibitory and increased activatory NK cell receptors.

Breath-Hold Blood Oxygen Level-Dependent MRI: A Tool for the Assessment of Cerebrovascular Reserve in Children with Moyamoya Disease.

BACKGROUND AND PURPOSE: There is a critical need for a reliable and clinically feasible imaging technique that can enable prognostication and selection for revascularization surgery in children with Moyamoya disease. Blood oxygen level-dependent MR imaging assessment of cerebrovascular reactivity, using voluntary breath-hold hypercapnic challenge, is one such simple technique. However, its repeatability and reliability in children with Moyamoya disease are unknown. The current study sought to address this limitation. MATERIALS AND METHODS: Children with Moyamoya disease underwent dual breath-hold hypercapnic challenge blood oxygen level-dependent MR imaging of cerebrovascular reactivity in the same MR imaging session. Within-day, within-subject repeatability of cerebrovascular reactivity estimates, derived from the blood oxygen level-dependent signal, was computed. Estimates were associated with demographics and intellectual function. Interrater reliability of a qualitative and clinically applicable scoring scheme was assessed. RESULTS: Twenty children (11 males; 12.1 ± 3.3 years) with 30 MR imaging sessions (60 MR imaging scans) were included. Repeatability was "good" on the basis of the intraclass correlation coefficient (0.70 ± 0.19). Agreement of qualitative scores was "substantial" (κ = 0.711), and intrarater reliability of scores was "almost perfect" (κ = 0.83 and 1). Younger participants exhibited lower repeatability (P = .027). Repeatability was not associated with cognitive function (P > .05). However, abnormal cerebrovascular reactivity was associated with slower processing speed (P = .015). CONCLUSIONS: Breath-hold hypercapnic challenge blood oxygen level-dependent MR imaging is a repeatable technique for the assessment of cerebrovascular reactivity in children with Moyamoya disease and is reliably interpretable for use in clinical practice. Standardization of such protocols will allow further research into its application for the assessment of ischemic risk in childhood cerebrovascular disease.

Does maternal exposure to artificial food coloring additives increase oxidative stress in the skin of rats?

Glutathione-S-transferase (GST) and cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) metabolize and detoxify carcinogens, drugs, environmental pollutants, and reactive oxygen species. Changes of GST expression in tissues and gene mutations have been reported in association with many neoplastic skin diseases and dermatoses. Widely used artificial food coloring additives (AFCAs) also reported to effect primarily behavioral and cognitive function and cause neoplastic diseases and several inflammatory skin diseases. We aimed to identify the changes in expression of GSTs, CYP1A1, and vascular endothelial growth factor (VEGF) in rat skin which were maternally exposed AFCAs. A rat model was designed to evaluate the effects of maternal exposure of AFCAs on skin in rats. "No observable adverse effect levels" of commonly used AFCAs as a mixture were given to female rats before and during gestation. Immunohistochemical expression of GSTs, CYP1A1, and VEGF was evaluated in their offspring. CYP1A1, glutathione S-transferase pi (GSTP), glutathione S-transferase alpha (GSTA), glutathione S-transferase mu (GSTM), glutathione S-transferase theta (GSTT), and VEGF were expressed by epidermal keratinocytes, dermal fibroblasts, sebaceous glands, hair follicle, and subcutaneous striated muscle in the normal skin. CYP1A1, GSTA, and GSTT were expressed at all microanatomical sites of skin in varying degrees. The expressions of CYP1A1, GSTA, GSTT, and VEGF were decreased significantly, while GSTM expression on sebaceous gland and hair follicle was increased. Maternal exposure of AFCAs apparently effects expression of the CYP1A1, GSTs, and VEGF in the skin. This prominent change of expressions might play role in neoplastic and nonneoplastic skin diseases.

Acquired reactive perforating collagenosis.

Acquired perforating disorder has been recognized as an uncommon distinct dermatosis in which altered collagen is eliminated through the epidermis. Several disorders accompanied by itching and scratching were reported to be associated with reactive perforating collagenosis. A 67-year-old white woman diagnosed as acquired reactive perforating collagenosis with poorly controlled diabetes mellitus and congestive cardiac failure is presented.

Concurrent skin and nerve histology in leprosy and its role in the classification of leprosy.

Concurrent skin and nerve histology was evaluated in 60 leprosy patients (25 BT, 28 BL and 7 LL). The twin aims were to study the comparative histology and the usefulness of nerve histology in the classification of the disease. In BT patients, clinical and histological classification was in agreement in 11 (44%) skin and 17 (68%) nerve biopsies. Concurrent skin and nerve histology was in consonance in 14 (56%) BT patients, while in 6 (24%) patients, only nerve histology was helpful in the classification of the disease, the skin histology being non-specific. Nerve histology was classified as BL in 3 (12%) BT patients, the skin histology was non-specific. In the BL group, the histology of 23 (82.4%) nerve biopsies correlated with the clinical classification, in contrast to skin histology which correlated with clinical assessment in 19 (68%) patients only. In the LL patients, the histology of nerve correlated with the clinical classification in 5 patients (71.4%), compared to histology of the skin in 4 (57%) patients only. The GF was higher in the nerves than in the skin throughout the leprosy spectrum (BT, BL, LL); the difference was, however, marginal in BL leprosy. The average bacteriological index (BI) was higher in nerves (4+) compared to that of skin histology and slit skin smears (3+) in BL leprosy. There was, however, no difference in the BI of the slit skin smears, skin and nerve biopsies in lepromatous leprosy.(ABSTRACT TRUNCATED AT 250 WORDS)

Culture of nocardioform bacilli from leprosy patients & clinical evaluation of nocardioform bacilli derived antigen.

An antigen derived from cultured nocardioform bacilli was compared with Mitsuda lepromin in intradermal skin test reactions. Nocardioform bacilli were cultured in gelatin minimal medium from the tissue fluid of 85 lepromatous patients (56 M, 29 F). Of these, 65 samples showed uncontaminated growth of the organism, which were pooled for the manufacture of the test antigen. This antigen was intradermally tested in 50 untreated leprosy patients irrespective of the type, together with Mitsuda lepromin and sterile gelatin minimal media, which served as a control. No early reaction was observed at 72 h, while the late reaction at 28 days was positive in all patients in the Tuberculoid (TT) group with both antigens. Eighteen patients (81.8%) in the Borderline tuberculoid (BT) group reacted strongly to Mitsuda lepromin at 28 days, while 21 patients (95.5%) in this group showed a strong late reaction with the test antigen. The lepromatous (LL) group did not show any reaction with the two antigens. It is inferred that nocardioform bacilli are easy to cultivate, and that the test antigen compares well with Mitsuda lepromin.

Probing the association behavior of poly(ethylene glycol)-based amphiphilic comb-like polymer in NaCl solution.

The effect of salt on the associative behavior of intramolecular aggregates obtained from poly(ethylene glycol)-based amphiphilic comb-like polymers in aqueous medium at pH 6.2 has been investigated by surface tension, fluorescence probe, dynamic light-scattering, and viscometry techniques. Results reveal that the addition of salt screens the electrostatic repulsion between the charges along the polymer backbone in the aggregates and consequently (1) reduces the surface activity at the air/water interface, (2) leads to the contraction of the polymer backbone, and (3) reduces the hydrodynamic sizes of the aggregates. In contrast, the hydrophobicity of the aggregates remains unperturbed.

The role of the antioxidative defense system in papulopustular acne.

Acne vulgaris frequently occurs in the second decade of life. The pathogenesis of the disease is multifactorial. In this study, we aimed to investigate the role of reactive oxygen species in inflammation of acne by determining the activity of antioxidant defense enzymes in leukocytes. Fifty-two patients with papulopustular type acne vulgaris and 36 healthy controls were enrolled. The severity of the disease was examined by the Global Acne Grading System, and the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) enzymes as well as the level of thiobarbituric acid reactive substance (TBARS) were detected in leukocytes. The activities of SOD and GSH-Px were significantly decreased in the acne group. CAT activity and TBARS level were higher in patients than controls. Only a poor correlation was detected between GSH-Px activity and severity of the disease. Antioxidative defense enzymes are impaired in papulopustular acne, and drugs with antioxidative effects might be valuable in treatment.

Electron microscopic characteristics of actinomycetic agents having aetiological association with human leprosy and epizootic ulcerative syndrome of fish.

The transmission electron microscopic (TEM) studies of the human leprosy derived chemoautotrophic nocardio-form (CAN) bacteria and EUS derived CAN bacteria showed presence of double contoured cell-walls consisting of an electron transparent and a dense layer. The fibrillar structures on the surface of these CAN bacterial cells also suggested their similarity to the human tissue derived Mycobacterium leprae cells. These EM studies further revealed mycelial and coccoid bodies in all these bacteria as was observed originally.

Paucibacillary multidrug therapy in leprosy. 7 1/2 years experience.

Three hundred and twenty-three paucibacillary (PB) leprosy patients were treated with WHO-recommended multidrug therapy (MDT) and followed up for over 7 1/2 years. The paucibacillary MDT regimen (PBR) was well accepted and tolerated. Complete clinical regression was attained in 61.2% patients after 6 doses of PBR. Persistence of clinical activity after 6 months of therapy was associated with occurrence of type I upgrading reaction, presence of six or more patches and more than two thickened major nerve trunks. Reversal reactions were encountered in 15.9% patients, one third of which were accompanied by severe neuritis. Delayed upgrading reaction occurred in six patients, two patients had relapse one and two years after stopping of PBR. The WHO recommended MDT regimen for paucibacillary cases needs careful evaluation and it may be necessary to extend the treatment beyond six months in certain situations.

Pilomatrixoma.

Clinical and histopathological features of two cases of pilomatrixoma are reported. The tumour in each case was slow-growing, asymptomatic and at the same site. Histopathology showed classical eosinophilic ghost cell, surrounded by basophilic cells, along with areas of calcification and keratinization.

Telomerase reverse transcriptase (TERT) expression and role of vincristine sulfate in mouse model of malignancy related peritoneal ascites: an experimental metastatic condition.

AIM: To evaluate the efficacy of intraperitoneal vincristine administration into ascitic sarcoma-180 bearing mice as a model of human malignant ascites regarding various peritoneal/retroperitoneal sarcomatosis, and to evaluate the flowcytometric telomerase reverse transcriptase expression for the diagnostic and prognostic purposes. METHODS: Present study included disease induction by intraperitoneal homologous ascitic sarcoma-180 transplantation followed by in vivo intraperitoneal drug administration to study mitotic index, flowcytometric cell cycle and telomerase reverse transcriptase expression pattern, erythrosin-B dye exclusion study for malignant cell viability assessment. Besides, in vitro malignant ascite culture in presence and absence of vincristine sulfate and survival study were also taken into consideration. RESULTS: Intraperitoneal vincristine administration (concentration 0.5 mg/kg body weight) significantly diminished the mitotic index in diseased subjects in comparison to untreated control subjects. Treated group of animals showed increased life span and median survival time. Cell viability assessment during the course of drug administration also revealed gradual depression on cell viability over time. Flowcytometric cell cycle analysis showed a good prognostic feature of chemotherapeutic administration schedule by representing high G2/M phase blocked cells along with reduced telomerase reverse transcriptase positive cells in treated animals. CONCLUSION: We conclude that long term administration of vincristine sulfate in small doses could be a good pharmacological intervention in case of malignant peritoneal ascites due to sarcomatosis as it indirectly reduced the level of telomerase reverse transcriptase expression in malignant cells by directly regulating cell cycle and simultaneously increased the life expectancy of the diseased subjects.