Reactivity of Thiolate and Hydrosulfide with a Mononuclear {FeNO}7 Complex Featuring a Very High N-O Stretching Frequency.

Synthesis, characterization, electronic structure, and redox reactions of a mononuclear {FeNO}7 complex with a very high N-O stretching frequency in solution are presented. Nitrosylation of [(LKP)Fe(DMF)]2+ (1) (LKP = tris((1-methyl-4,5-diphenyl-1H-imidazol-2-yl)methyl)amine) produced a five-coordinate {FeNO}7 complex, [(LKP)Fe(NO)]2+ (2). While complex 2 could accommodate an additional water molecule to generate a six-coordinate {FeNO}7 complex, [(LKP)Fe(NO)(H2O)]2+ (3), the coordinated H2O in 3 dissociates to generate 2 in solution. The molecular structure of 2 features a nearly linear Fe-N-O unit with an Fe-N distance of 1.744(4) Å, N-O distance of 1.162(5) Å, and

Silver nanostructure-modified graphite electrode for in-operando SERRS investigation of iron porphyrins during high-potential electrocatalysis.

In-operando spectroscopic observation of the intermediates formed during various electrocatalytic oxidation and reduction reactions is crucial to propose the mechanism of the corresponding reaction. Surface-enhanced resonance Raman spectroscopy coupled to rotating disk electrochemistry (SERRS-RDE), developed about a decade ago, proved to be an excellent spectroscopic tool to investigate the mechanism of heterogeneous oxygen reduction reaction (ORR) catalyzed by synthetic iron porphyrin complexes under steady-state conditions in water. The information about the formation of the intermediates accumulated during the course of the reaction at the electrode interface helped to develop better ORR catalysts with second sphere residues in the porphyrin rings. To date, the application of this SERRS-RDE setup is limited to ORR only because the thiol self-assembled monolayer (SAM)-modified Ag electrode, used as the working electrode in these experiments, suffers from stability issues at more cathodic and anodic potential, where H2O oxidation, CO2 reduction, and H+ reduction reactions occur. The current investigation shows the development of a second-generation SERRS-RDE setup consisting of an Ag nanostructure (AgNS)-modified graphite electrode as the working electrode. These electrodes show higher stability (compared to the conventional thiol SAM-modified Ag electrode) upon exposure to very high cathodic and anodic potential with a good signal-to-noise ratio in the Raman spectra. The behavior of this modified electrode toward ORR is found to be the same as the SAM-modified Ag electrode, and the same ORR intermediates are observed during electrochemical ORR. At higher cathodic potential, the signatures of Fe(0) porphyrin, an important intermediate in H+ and CO2 reduction reactions, was observed at the electrode-water interface.

Linear morphea with overlying lichen sclerosus and calcinosis cutis associated with juvenile dermatomyositis.

Juvenile dermatomyositis (JDM) is associated with many distinguishing features including cutaneous calcinosis, vasculitis, and ulcerated lesions. In this case, we describe an unusual presentation in a 12-year-old girl who had muscle weakness along with linear morphea over the right upper and lower extremities with overlying lichen sclerosus and calcinosis cutis. Of interest, these initial cutaneous manifestations occurred years before onset of myositis.

Bioinorganic Chemistry on Electrodes: Methods to Functional Modeling.

One of the major goals of bioinorganic chemistry has been to mimic the function of elegant metalloenzymes. Such functional modeling has been difficult to attain in solution, in particular, for reactions that require multiple protons and multiple electrons (nH+/ne-). Using a combination of heterogeneous electrochemistry, electrode and molecule design one may control both electron transfer (ET) and proton transfer (PT) of these nH+/ne- reactions. Such control can allow functional modeling of hydrogenases (H+ + e- → 1/2 H2), cytochrome c oxidase (O2 + 4 e- + 4 H+ → 2 H2O), monooxygenases (RR'CH2 + O2 + 2 e- + 2 H+ → RR'CHOH + H2O) and dioxygenases (S + O2 → SO2; S = organic substrate) in aqueous medium and at room temperatures. In addition, these heterogeneous constructs allow probing unnatural bioinspired reactions and estimation of the inner- and outer-sphere reorganization energy of small molecules and proteins.

Umbilicated papulonodules on the elbows with purpuric papules on the fingers.

This case describes an unusual cutaneous presentation. Our patient had purpuric papules on the fingers and umbilicated nodules over the elbows, and interestingly, both lesion types showed similar histopathological features of necrobiotic granuloma with neutrophils.

Is weekly azathioprine pulse effective and safe in dermatological conditions?

Azathioprine, a purine synthesis inhibitor is widely used as an effective immunosuppressant in several immune mediated diseases, usually in a dose of 2 to 2.5 mg/kg per day. The pulse dose of azathioprine is an unique once weekly dosing regimen, which has been used as an alternative to daily dose regimen in some immune mediated dermatologic disorders. In this review, we looked at a specific dosing regimen, "weekly azathioprine pulse" with respect to its efficacy and safety in the treatment of dermatologic diseases. We performed a literature search for studies on azathioprine weekly pulse in dermatology in various scientific databases using keywords "azathioprine-pulse", "dermatology", "weekly azathioprine", and so on. Dosing regimens, indications, efficacy, monitoring, and side effect profile as described in these studies were recorded. Evidence level of the regimens used in various indications was also calculated. We could find six published studies using azathioprine weekly pulse, of which three were randomized comparative clinical trials. Azathioprine pulse was administered in a dose of 300 mg (6 tablets of 50 mg each) every week in all the studies. It has been found to be effective in management of contact dermatitis due to parthenium (IB), chronic plaque psoriasis (IIB), and alopecia areata (IB). Adverse effect profile was found to be almost similar to daily azathioprine. Weekly azathioprine pulse, therefore, appears to be an effective and safe alternative to daily azathioprine in the management of immune mediated disorders in dermatology. Although studies are limited, this regimen seems promising and further studies are warranted.

Stepwise treatment of primary focal hyperhidrosis with aluminum chloride hexahydrate lotion (20%) and oral glycopyrrolate: a retrospective study from a tertiary care center.

Primary focal hyperhidrosis is a common reason for dermatology outpatient visit and has significant impact on patient's social and professional activities. The study describes the clinical profile of those patients and response with aluminum chloride hexahydrate lotion (ACH 20%) and oral glycopyrrolate (OGP). A retrospective study was carried out at a tertiary care center between the year 2016 and 2018. Details of history, baseline assessment, treatment response recorded in specially designed proformas were analyzed. Initially, the patients received topical ACH daily at night. Non-responders were advised OGP 1 mg BD and increased to 2 mg BD if they did not respond. Response was measured according to patient global assessment and objective evaluation of sweating. Among total 69 patients 57 had onset <10 years of age. There was male preponderance and most common trigger was situations causing anxiety (n = 15). Around 15.3% patients got adequate response with ACH lotion. The cumulative response increased to 45.8% by addition of OGP 1 mg BD and to 55.9% by increasing the dose to 2 mg BD. Addition of OGP to topical ACH increases the treatment efficacy in patients with primary focal hyperhidrosis. Increasing the glycopyrrolate dose augments the response further. However, the current medical treatment options are able to give moderate response.