Novel reaction to new cystic fibrosis medication Trikafta.

We present a novel case of an urticaria multiforme-type drug reaction to the new cystic fibrosis medication Trikafta (elexacaftor + tezacaftor + ivacaftor). Equipped with this information, clinicians may be more prepared to counsel and treat patients if they experience similar symptoms after beginning Trikafta.

Case and review: Cutaneous involvement by chronic neutrophilic leukemia vs Sweet syndrome- A diagnostic dilemma.

Chronic neutrophilic leukemia (CNL) is a rare leukemia with approximately 150 total cases reported. Cutaneous neutrophilic infiltrates, including Sweet syndrome (SS) and leukemia cutis (LC), have been reported in six patients with CNL. In the setting of CNL, these two conditions are difficult to differentiate due to clinical and histopathological similarities, but it is important to do so because LC is associated with a worse prognosis. In general, SS is distinguished by its tenderness, fever, and improvement with steroids (vs chemotherapy for LC). Biopsy of LC reveals immature leukocytes, whereas SS shows almost exclusively mature leukocytes, but morphology alone may not be sufficient in some cases. Here, we report a case of a 72-year-old male with CNL and a cutaneous eruption with clinical and pathological features which made the distinction between the two diseases difficult.

Measuring Electronic Spectra of Differential Mobility-Selected Ions in the Gas Phase.

We describe the modification of a commercially available tandem differential mobility mass spectrometer (DMS) that has been retrofitted to facilitate photodissociation (PD) of differential mobility-separated, mass-selected molecular ions. We first show that a mixture of protonated quinoline/isoquinoline (QH+/iQH+) can be separated using differential mobility spectrometry. Efficient separation is facilitated by addition of methanol to the DMS environment and increased residence time within the DMS. In action spectroscopy experiments, we gate each isomer using appropriate DMS settings, trap the ions in the third quadrupole of a triple quadrupole mass spectrometer, and irradiate them with tunable light from an optical parametric oscillator (OPO). The resulting mass spectra are recorded as the OPO wavelength is scanned, giving PD action spectra. We compare our PD spectra with previously recorded spectra for the same species and show that our instrument reproduces previous works faithfully.

Sports Dermatology: Skin Disease in Athletes.

There are numerous disorders of the skin that occur in athletes. These include infections, mechanical injury, and inflammatory skin diseases such as dermatitis, urticaria, and others. This paper discusses some of the most common athletic skin diseases.

The structures and properties of anionic tryptophan complexes.

The physicochemical properties of [Trpn-H]- and [TrpnCl]- (n = 1, 2) have been investigated in a combined computational and experimental infrared multiple dissociation (IRMPD) study. IRMPD spectra within the 850-1900 cm-1 region indicate that deprotonation is localized on the carboxylic acid moiety in [Trpn-H]- clusters. A combination of hydrogen bonding and higher order charge-quadrupole interactions appear to influence cluster geometries for all investigated systems. Calculated global minimum and low energy geometries of [TrpCl]- and [Trp2Cl]- clusters favour coordination of the halide by the indole NH. [Trp2-H]- and [Trp2Cl]- exhibit additional π-π interactions between the heterocyclic side chains.

Infrared-Driven Charge-Transfer in Transition Metal-Containing B12X122- (X = H, F) Clusters.

Density functional theory (DFT) calculations and infrared multiple photon dissociation (IRMPD) spectroscopy are employed to probe [TM·(B12H12)]- and [TM·(B12H12)2]2- clusters [TM = Ag(I), Cu(I), Co(II), Ni(II), Zn(II), Cd(II)]. A comparison is made between the charge-transfer properties of the clusters containing the hydrogenated dodecaborate dianions, B12H122-, and the fluorinated analogues, B12F122-, for clusters containing Cd(II), Co(II), Ni(II), and Zn(II). IRMPD of the [TM·(B12H12)]- and [TM·(B12H12)2]2- species yields B12H11- via hydride abstraction and B12H12- in all cases. To further explore the IR-induced charge-transfer properties of the B12X122- (X = H, F) cages, mixed-cage [TM(B12H12)(B12F12)]2- [TM = Co(II), Ni(II), Zn(II), Cd(II)] clusters were investigated. IRMPD of the mixed-cage species yielded appreciable amounts of B12F12- and B12H12- in most cases, indicating that charge-transfer to the central TM cation is a favorable process; formation of B12F12- is the dominant process for the Co(II) and Ni(II) mixed-cage complexes. In contrast, the Zn(II) and Cd(II) mixed-cage complexes preferentially produced fragments of the form B xH yF z-/2-, suggesting that H/F scrambling and/or fusion of the boron cages occurs along the IRMPD pathway.

Mode-Selective Laser Control of Palladium Catalyst Decomposition.

It is generally assumed that molecules behave ergodically during chemical reactions, that is, reactivities depend only on the total energy content and not on the initial state of the molecule. While there are a few examples of nonergodic behavior in small (usually electronically excited) species, to date there have been no reports of such behavior in larger covalently bound species composed of several tens of atoms. Here, we demonstrate vibrational mode-selective behavior in a series of palladium catalysts. When we excite solvent-tagged gas-phase Pd catalysts with an infrared laser that is tuned to be resonant with specific molecular vibrations, depending on which vibration we excite, we can select different reaction pathways. We also demonstrate that this behavior can be "turned off" via chemical substitution.

Intramolecular cation-π interactions in protonated phenylalanine derivatives.

The structures and properties of a series of phenylalanine (Phe) derivatives have been investigated in a joint computational and experimental infrared multiple photon dissociation (IRMPD) study. IRMPD spectra in the 1000-2000 cm-1 region show that protonation is localized on the amine group in all cases. Intramolecular cation-π interactions between the ammonium group and the phenyl ring heavily influence molecular geometries and properties such as gas phase basicity and proton affinity. By varying substituents on the phenyl ring, one can sensitively tune the cation-π interaction and, therefore, the molecular structure and properties. Variations in molecular structures and properties as a function of phenyl ring substitution are shown to correlate with substituent Hammett parameters.

The structures and properties of proton- and alkali-bound cysteine dimers.

The proton-, lithium-, and sodium-bound cysteine dimers have been investigated in a joint computational and experimental infrared multiple photon dissociation (IRMPD) study. IRMPD spectra in the 1000-2000 cm(-1) region show that protonation is localized on an amine group, and that intermolecular hydrogen bonding occurs between the protonated amine and the carbonyl oxygen of the neutral Cys moiety. Alkali-bound dimers adopt structures reminiscent of those observed for the monomeric Cys·Li(+) and Cys·Na(+) species. Calculations of the heavier Cys2·M(+) (M = K, Rb or Cs) species suggest that these are significantly less strongly bound than the lighter (M = H, Li, or Na) dimers.

Gaucher Disease Type 2 Presenting with Collodion Membrane and Blueberry Muffin Lesions.

Collodion membrane is most closely associated with forms of autosomal recessive congenital ichthyosis, but the differential diagnosis includes many other less common etiologies. Herein we present a case of Gaucher disease (GD) type 2 in a neonate presenting with collodion membrane in addition to blueberry muffin lesions. The clinical presentation and etiology of GD and the differential diagnoses for collodion membrane and blueberry muffin lesions are briefly reviewed.

Greater Strength Drives Difference in Power between Sexes in the Conventional Deadlift Exercise.

Limited research exists comparing sex differences in muscular power. The primary purpose of this research was to determine if differences exist in power and velocity in the conventional deadlift (CDL). A secondary purpose was to examine the relationship among power, velocity, strength, and fat free mass (FFM). Eighteen strength trained athletes with ≥1 year CDL experience (women: n = 9, 29 ± 2 years, 162.3 ± 1.8 cm, 62 ± 2.4 kg, 23.3 ± 3.2 % body fat (%BF); men: n = 9, 29 ± 3 years, 175.6 ± 1.8 cm, 85.5 ± 1.4 kg, 14.8 ± 2.4 %BF), and ≥1.5 one repetition maximum (1-RM) CDL: body mass (BM) ratio (women: 1.6 ± 0.1 1-RM CDL: BM; men: 2.3 ± 0.1 1-RM CDL: BM), performed baseline (body composition, 1-RM CDL) and experimental sessions, in which velocity and power were measured at 30%, 60%, and 90% 1-RM. Repeated measures ANOVA and bivariate correlations were conducted. Men produced higher absolute average and peak power across all loads, but higher average velocity at only 30% 1-RM. When normalized to FFM, men produced higher peak and average power; however, women produced higher peak and average velocities across all loads. FFM and 1-RM were correlated with power. Greater power observed in men is driven by larger muscle mass, which contributes to greater strength.

Infrared-Driven Charge Transfer in Transition Metal B12F12 Clusters.

A combination of infrared multiple photon dissociation (IRMPD) spectroscopy and density functional theory calculations is used to investigate the structures and charge-transfer properties of clusters containing transition metals (TM = Co(II), Ni(II), Cu(I), Zn(II), Rh(III), Pd(II), Ag(I), Cd(II)) and the dodecafluorododecaboron dianion, B12F12(2-). In all cases, IRMPD resulted in transfer of electron density to the metal center and production of B12F12(-). Metals that exhibit the highest degree of charge transfer are found to induce reaction among the B12F12 cages, leading to production of BnFm (up to n = m = 24).

Vinylnitrene formation from 3,5-diphenyl-isoxazole and 3-benzoyl-2-phenylazirine.

Photolysis of 1 in argon-saturated acetonitrile yields 2, whereas in oxygen-saturated acetonitrile small amounts of benzoic acid and benzamide are formed in addition to 2. Similarly, photolysis of 2 in argon-saturated acetonitrile results in 1 and a trace amount of 3, whereas in oxygen-saturated acetonitrile the major product is 1 in addition to the formation of small amounts of benzoic acid and benzamide. Laser flash photolysis of 1 results in an absorption due to triplet vinylnitrene 4 (broad absorption with λ(max) at 360 nm, τ = 1.8 µs, acetonitrile) that is formed with a rate constant of 1.2 × 10(7) s(-1) and decays with a rate constant of 5.6 × 10(5) s(-1). Laser flash photolysis of 2 in argon-saturated acetonitrile likewise results in the formation of triplet vinylnitrene 4 but also ylide 5 (λ(max) at 440 nm, τ = 13 µs). The rate constant for forming 4 in argon-saturated acetonitrile is 1.6 × 10(7) s(-1). In oxygen-saturated acetonitrile, vinylnitrene 4 reacts to form the peroxide radical 6 (λ(max) 360 nm, ~0.7 µs, acetonitrile) at a rate of 2 × 10(9) M(-1) s(-1). Density functional theory calculations were performed to aid in the characterization of vinylnitrene 4 and peroxide 6 and to support the proposed mechanism for the formation of these intermediates.

Acute renal infarction: an unusual cause of abdominal pain.

Acute renal infarction is an uncommon and under-diagnosed disease. Its clinical presentation is nonspecific and often mimics other more common disease entities. The diagnosis is usually missed or delayed, which frequently results in irreversible renal parenchyma damage. High index of suspicion is required for early diagnosis, as timely intervention may prevent loss of kidney function. We report a case of acute renal infarction following coronary angiography in a patient with paroxysmal atrial fibrillation who initially presented with acute abdominal pain mimicking appendicitis.