Mini-implant-supported twin-block appliance: An innovative modification.

Twin block is a commonly used appliance for correction of retrognathic mandible in growing patients. However, it has a drawback of causing lower incisor proclination, which reduces its potential of achieving maximum skeletal effects. Thus, we introduced a novel modification in the present design to facilitate greater anteroposterior effects in skeletal dimension. The aim of the present case reports is to evaluate the efficacy of this modified twin block. Here we present two cases treated with mini-implant-supported twin-block appliance, which successfully controlled the lower incisor position, thereby increasing the envelope for orthopedic correction in class II myofunctional therapy. This modification is useful in growing patients with retruded mandible to achieve maximum skeletal effects.

Atomic layer deposition of nickel-cobalt spinel thin films.

We report the atomic layer deposition (ALD) of high-quality crystalline thin films of the spinel-oxide system (Co1-xNix)3O4. These spinel oxides are ferrimagnetic p-type semiconductors, and promising material candidates for several applications ranging from photovoltaics and spintronics to thermoelectrics. The spinel phase is obtained for Ni contents exceeding the x = 0.33 limit for bulk samples. It is observed that the electrical resistivity decreases continuously with x while the magnetic moment increases up to x = 0.5. This is in contrast to bulk samples where a decrease of resistivity is not observed for x > 0.33 due to the formation of a rock-salt phase. From UV-VIS-NIR absorption measurements, a change from distinct absorption edges for the parent oxide Co3O4 to a continuous absorption band ranging deep into the near infrared for 0 < x ≤ 0.5 was observed. The conformal deposition of dense films on high-aspect-ratio patterns is demonstrated.

Anomalous thickness-dependent optical energy gap of ALD-grown ultra-thin CuO films.

Usually an inverse square relation between the optical energy gap and the size of crystallites is observed for semiconducting materials due to the strong quantum localization effect. Coulomb attraction that may lead to a proportional dependence is often ignored or considered less important to the optical energy gap when the crystallite size or the thickness of a thin film changes. Here we report a proportional dependence between the optical energy gap and the thickness of ALD-grown CuO thin films due to a strong Coulomb attraction. The ultrathin films deposited in the thickness range of 9-81 nm show a p-type semiconducting behavior when analyzed by Seebeck coefficient and electrical resistivity measurements. The indirect optical energy gap nature of the films is verified from UV-vis spectrophotometric measurements. A progressive increase in the indirect optical energy gap from 1.06 to 1.24 eV is observed with the increase in the thickness of the films. The data are analyzed in the presence of Coulomb attractions using the Brus model. The optical energy gap when plotted against the cubic root of the thickness of the films shows a linear dependence.

Isovalent Ca and Ba substitutions in thermoelectric layer-structured oxyselenide Sr2CoO2Cu2Se2.

Multilayered compounds typically present exotic functionalities, and some of them have been suggested as potential materials for thermoelectric conversion owing to their unique capability to decouple electronic and heat transport. Here we report new [CoO2] and [Cu2Se2] layered A2CoO2Cu2Se2 compounds in which Sr at the intervening alkaline-earth A site is partially replaced with Ca or Ba. The parent Sr2CoO2Cu2Se2 phase is a direct gap p-type semiconductor, and density functional theory (DFT) calculations indicate its topmost valence band consists of Cu 3d-Se 4p states. Upon the isovalent cation substitution the lattice modification in the ab plane is constrained by the stiff [CoO2] layer such that the lattice shrinkage/expansion mainly happens along the c axis. Substitution of Sr with the heavier and larger Ba significantly enhances the thermopower but more hole states would be required to optimize the thermoelectric performance. Thermal stability is related to the inter-oxide-selenide-layer interaction, and our thermogravimetric measurement data reveal that the A2CoO2Cu2Se2 materials could operate in the intermediate temperature region.

An experimental setup for the simultaneous measurement of thermoelectric power of two samples from 77 K to 500 K.

We report on an experimental setup for the simultaneous measurement of the thermoelectric power (TEP) of two samples in the temperature range from 77 K to 500 K using optimum electronic instruments. The setup consists of two rectangular copper bars in a bridge arrangement for sample mounting, two surface mount (SM) chip resistors for creating alternate temperature gradient, and a type E thermocouple in differential geometry for gradient temperature (ΔT) measurement across the samples. In addition, a diode arrangement has been made for the alternate heating of SM resistors using only one DC current source. The measurement accuracy of ΔT increases with the differential thermocouple arrangement. For the calibration of the setup, measurements of TEP on a high purity (99.99%) platinum wire and type K thermocouple wires Chromel and Alumel have been performed from 77 K to 500 K with respect to copper lead wires. Additionally, this setup can be utilized to calibrate an unknown sample against a sample of known absolute TEP.

Biochemical alteration of hepatic functions by histamine H3-receptor agonist and antagonist in immunized rabbits.

AIM: The aim of our study was to investigate the functional roles of H3R agonist and antagonist in the development of hepatic functions impairment in immunized rabbits. METHODS: The study comprised of six groups containing 18 rabbits in each. Group-I (negative control) and group-II (positive control) received sterile distilled water intramuscularly while Group III-VI received histamine (100 µgkg-1, s.c.), R-[-]-α-methylhistamine (H3R-agonist, 10 µgkg-1, s.c.), iodophenpropit (H3R-antagonist, 1 µgkg-1, i.m.), and the combination of iodophenpropit (1 µgkg-1, i.m.) plus histamine (100 µgkg-1, s.c.), respectively, b.i.d. (12 hours [8 am and 8 pm]) for 10 days. Groups II-VI were immunized on day 3 with intravenous injection of sheep red blood cells (1×109 cells/ml). RESULTS: On each experimental day, the mean values of serum enzymes and bilirubin in group-I and group-II showed no changes while in groups III, IV, V, and VI, these enzymes and bilirubin levels showed significant changes (p<0.05), when compared with their values within the group. Profile of ALT and AST production revealed that ALT and AST levels moderately were changed due to degeneration of the liver. CONCLUSION: Our results suggest that R-[-]-α-methylhistamine showed moderate, and histamine and iodophenpropit showed mild degeneration of liver functions; while iodophenpropit plus histamine showed hepatic functions similar to control group. This study suggests that H3R antagonist in combination with histamine may be a non-toxic therapeutic target for histamine research (Fig. 7, Ref. 28). Text in PDF www.elis.sk.

In vivo study of histamine H4 receptor in immunomodulation.

OBJECTIVE: Recently accumulating evidence has highlighted the role of histamine in inflammation and immune reaction by histamine H4-receptor, however the role of histamine via H4-receptor in immunomodulation is still unclear. Therefore, the present study was designed to study the immunomodulatory role of histamine H4-receptor on antibody generation profile in rabbit. METHODS: The cohort study comprised of 108 rabbits in six groups. Each group consisted of 18 rabbits. Group I (negative control) remained non-immunized and received vehicle (sterile distilled water, 1 mlkg-1 × b.i.d., s.c. for 10 days (3 days prior to immunization until 7 days after immunization)). Group II (positive control) received vehicle (1 mlkg-1 × b.i.d., s.c. for 10 day), while group III-VI received histamine (100 µgkg-1 × b.i.d., s.c.), H4-agonist (clobenpropit dihydrobromide, 10 µgkg-1 × b.i.d., s.c.), and H4-antagonist (JNJ 7777120, 10 µgkg-1 × b.i.d., i.m.) and DMSO (control group for H4R-antagonist, 1 mlkg-1 × b.i.d., i.m.) respectively for 10 days. Group II-VI were immunized with intravenous injection of sheep red blood cells (SRBC) on day 3. Immunological parameters [immunoglobulins (Ig), immunoglobulin M (IgM), and immunoglobulin G (IgG)] assessed by the whole SRBC-ELISA method and direct hemagglutination assay. RESULTS: Histamine could influence a detectable antibody response to SRBC as early as day 7 postimmunization (post-I), which lasted until day 58 post-I, whereas H4-receptor by H4R-antagonist treatment showed a similar profile of antibody (Ig, IgM, and IgG) generation as the positive control group. On the other hand, H4R-agonist treatment showed immunostimulant activity as compared to other experimental groups. The results were found statistically significant (p<0.01). CONCLUSIONS: Histamine H4-receptor in biological system modulates immunological function and stimulates antibody production only by exogenously administered agonists not by endogenous histamine (Tab. 1, Fig. 3, Ref. 26).

Pharmaco-EcoMicrobiology: a newer component of medical sciences bridging pharmacovigilance, ecology, and environmental microbiology.

Environmental scientists are now raising great concern on the impact of drugs on the environment and microbiologists are concerned about increasing antibiotic resistance due to irrational usage. However, a focus on the impact by the use of antibiotics (irrational/prescribed) to the environment at therapeutic doses has not been instituted. Even the World Health Organization (WHO) defined "Pharmacovigilance" activities as the monitoring, detection, assessment, understanding and prevention of any adverse reactions to drugs at therapeutic concentration on animals and humans. Nevertheless, there is little attention being given to identifying the adverse effects (ADEs) of antimicrobial agents on the environment (given at therapeutic doses). This issue has been highlighted in the present commentary and a new domain, "Pharmaco-EcoMicrobiology", has been proposed which should deal with and monitor such adverse effects. The term "Pharmaco-EcoMicrobiology" has been proposed to define the interplay between antimicrobial pharmacological agents and animate microbial ecology. This new domain, "Pharmaco-EcoMicrobiology", has been derived by the aggregation of three important branches of science (pharmacology+ecology+microbiology) and would be responsible for studying the ADEs due to antimicrobial drugs excreted in environment.

Surface pH of Normal Skin.

The skin furface pH of 55 brown-skinned individuals (Indians) comprising of 30 males and 25 females in the age range 12-58 years has been measured at the forehead (FH) and the back of the wrist (BW). The mean values of skin pH at FH and BW are 5.51 + 0.32 and 5.56 + 0.40 respectively for male. The corresponding female values are 5.73 + 0.032 and 5.84 + 0.28 statistical analysis of the data shows that (i) the dependence of skin surface pH on age is not significant, (ii) the male skin is slightly, but significantly more acidic than the female one, (iii) the mean values of skin pH at forehead and at back of the wrist do not differ significantly for male ; the difference however is significant for female at 5% level, (iv) there exists a significant positive correlation ( r=0.77 for male and r + 0.71 for female) between the pH's of the forehead (x2) and the back of the wrist (z3). The regression equation of x2 on x3 are: x2= 2.13+0.61 for male and x2=1.05 + 0.80x3 for female.