A Rare Case of Olmesartan-Associated Enteropathy Successfully Managed With Steroid Taper.

Olmesartan is a commonly used antihypertensive medication belonging to the class of angiotensin II receptor blockers. Though generally well-tolerated, olmesartan can rarely cause olmesartan-associated enteropathy (OAE) with non-bloody diarrhea, weight loss, abdominal pain, and vomiting. Patients may develop enteropathy months to years after drug initiation. In severe cases, patients may develop complications that require hospitalization. Diagnosis is often delayed due to unfamiliarity of OAE, nonspecific presenting symptoms, and normal-appearing gross endoscopic findings. Esophagogastroduodenoscopy (EGD) with biopsy is essential to the diagnosis, showing sprue-like enteropathy with intestinal villous atrophy and mucosal inflammation. This report describes a case of a 70-year-old man who presented with three months of profuse watery diarrhea and 40-pound unintentional weight loss. After an extensive workup, including EGD with duodenal biopsies, the patient was diagnosed with OAE. The biopsies showed findings consistent with acute and chronic duodenitis, mucosal desquamation and ulceration, blunting of villi, and a sprue-like pattern with neutrophils. Celiac serologies and anti-enterocyte antibodies were negative, further supporting the diagnosis of OAE. Complete resolution of symptoms was achieved by discontinuing olmesartan and administering a steroid taper. Considering the frequent use of olmesartan, the increasing occurrence of OAE, and the wide range of associated symptoms, it is crucial for providers to recognize OAE and consider early discontinuation of olmesartan. This approach can help prevent further intestinal damage, protracted symptoms, unnecessary diagnostic tests, and financial burdens on both patients and the healthcare system.

PD-L1 Expression in Extramammary Paget Disease: A Case Series.

ABSTRACT: The PD-1/PD-L1 pathway plays a critical role in the physiologic inhibition and modulation of the immune response in normal tissue. Many tumors evade immune detection and response by upregulating PD-L1 expression. Humanized monoclonal PD-1 and PD-L1 antibodies have proven as both tolerable and effective treatment in many neoplasms. Extramammary Paget disease (EMPD) is a deformative and debilitating cutaneous malignancy in which definitive treatment options are limited with high recurrence rates after surgical excision. To the best of our knowledge, there is little published information regarding EMPD and PD-L1 expression. We evaluated 18 EMPD surgical pathology cases for tumor cell and tumor-associated inflammatory (TAI) cell PD-L1 expression. We identified PD-L1 tumor cell expression in 3 (17%) of the cases: 2 of 4 invasive cases (50%) and 1 of 14 (7%) noninvasive cases. One invasive case had lymph nodal metastasis with PD-L1 tumor cell expression. The host inflammatory response intensity and PD-L1 expression were variable in cases negative for tumor cell PD-L1 expression; however, a marked inflammatory response and TAI PD-L1 expression were present in all cases positive for tumor cell PD-L1 expression. In conclusion, 1 in 14 (7%) in situ EMPD cases showed tumor cell PD-L1 expression and 2 of 4 invasive cases (50%) showed tumor cell PD-L1 expression. TAI cells were more often positive (83%) than tumor cells (17%) for PD-L1 expression.

A Case of Severe Cardiac Sarcoidosis with Minimal Pulmonary Involvement: A Case Report with Literature Review.

Sarcoidosis is a granulomatous disease of unknown etiology. Although sarcoidosis is a systemic disease, there appears to be a predilection for involvement of certain organs. The pulmonary system is the most commonly affected system among all racial groups. Cardiac and respiratory complications are the leading causes of death due to sarcoidosis and in certain patient populations about half of these deaths are attributed to cardiac sarcoidosis. There are few autopsy case reports of cardiac sarcoidosis with minimal respiratory involvement making this case report relevant to the importance of the recognition and awareness of this entity. Acad Forensic Pathol. 2018 8(2): 407-415.

Bile Cast Nephropathy in Cirrhotic Patients: Effects of Chronic Hyperbilirubinemia.

OBJECTIVES: The aim of this study was to determine the prevalence of bile cast nephropathy (BCN) in autopsied cirrhotic patients and to correlate BCN with clinical and laboratory data to direct attention to this underrecognized renal complication of liver failure. METHODS: We assessed 114 autopsy cases of cirrhosis for the presence of renal intratubular bile casts using Hall stain for bile. Presence of bile casts was correlated with etiology of cirrhosis, clinical and laboratory data, and histologic findings. RESULTS: Bile casts were identified in 55% of cases. The most common etiology of cirrhosis was hepatitis C virus (HCV) infection (52%), and serum creatinine ( P = .02) and serum urea nitrogen ( P = .01) were significantly higher in the Hall-positive group. Conjugated bilirubin was below 20 mg/dL in 90%, and levels below 10 mg/dL were noted in 80% of cases. CONCLUSIONS: To our knowledge, this is the largest study of BCN in human subjects and a first report describing the association of BCN with HCV-related cirrhosis. We demonstrated that in the face of protracted chronic hyperbilirubinemia, bile casts are formed at much lower bilirubin levels than previously thought. Furthermore, we proposed an algorithm to assist in better identification of bile casts.

PlantID - DNA-based identification of multiple medicinal plants in complex mixtures.

BACKGROUND: An efficient method for the identification of medicinal plant products is now a priority as the global demand increases. This study aims to develop a DNA-based method for the identification and authentication of plant species that can be implemented in the industry to aid compliance with regulations, based upon the economically important Hypericum perforatum L. (St John's Wort or Guan ye Lian Qiao). METHODS: The ITS regions of several Hypericum species were analysed to identify the most divergent regions and PCR primers were designed to anneal specifically to these regions in the different Hypericum species. Candidate primers were selected such that the amplicon produced by each species-specific reaction differed in size. The use of fluorescently labelled primers enabled these products to be resolved by capillary electrophoresis. RESULTS: Four closely related Hypericum species were detected simultaneously and independently in one reaction. Each species could be identified individually and in any combination. The introduction of three more closely related species to the test had no effect on the results. Highly processed commercial plant material was identified, despite the potential complications of DNA degradation in such samples. CONCLUSION: This technique can detect the presence of an expected plant material and adulterant materials in one reaction. The method could be simply applied to other medicinal plants and their problem adulterants.

Molecular identification of Hypericum perforatum by PCR amplification of the ITS and 5.8S rDNA region.

The nuclear ribosomal internal transcribed spacer (ITS) sequences of eight Hypericum species were used to design H. perforatum-specific PCR primers by identification of short "microcode" sequences characteristic of the target species. These were tested with three vouchered H. perforatum DNA samples and eight samples from other species within the Hypericum genus. The most efficient primer combination, FO2 and HRI-S, amplified the genomic DNA from all three H. perforatum samples but not from any of the others apart from H. delphicum. The primer pairing was then tested against seven commercially available ornamental varieties of Hypericum; a positive result was obtained only with the H. perforatum sample. Three consumer products retailed as "St. John's wort" herbal remedies were sampled, two of which gave a positive result for H. perforatum. The assay was sensitive enough to detect 0.75 ng H. perforatum present as just 0.1 % of the total DNA. This method has the potential to be replicated in other plant species and presents a novel use for DNA barcoding data.

Complex modulation of L-type Ca(2+) current inactivation by sorcin in isolated rabbit cardiomyocytes.

Modulation of the L-type Ca(2+) channel (LTCC) by sorcin was investigated by measuring the L-type Ca(2+) current (I (Ca,L)) in isolated rabbit ventricular myocytes using ruptured patch, single electrode voltage clamp in the absence of extracellular Na(+). Fifty millimolars EGTA (170 nM Ca(2+)) in the pipette solution buffered bulk cytoplasmic [Ca(2+)], but retained rapid Ca(2+)-dependant inactivation of I (Ca,L,). Recombinant sorcin (3 microM) in the pipette significantly slowed time-dependant inactivation (tau (fast): 8.8 +/- 0.9 vs. 15.1 +/- 1.7 ms). Sorcin had no significant effect on I (Ca,L,) after inhibition of the sarcoplasmic reticulum (SR). Using 10 mM 1,2-bis(o-N,N,N',N'-tetraacetic acid (170 nM Ca(2+)), I (Ca,L) inactivation was then determined by a Ca(2+) -independent, voltage-dependant process. Under these conditions, 3 microM sorcin speeded up inactivation. A similar effect was observed by substitution of Ca(2+) with Ba(2+). Down-regulation of endogenous sorcin to 27 +/- 7% using an RNAi adenoviral vector slowed inactivation of I (Ca,L) by approximately 42%. The effects of sorcin on voltage-dependant inactivation were mimicked by a truncated form of the protein containing only the Ca(2+)-binding domain. This data is consistent with two independent actions of sorcin on the LTCC: (1) slowing Ca(2+)-dependant inactivation and (2) stimulating voltage-dependant inactivation. The net effect of sorcin on the time-dependent inactivation of I (Ca,L) was a balance between these two effects. Under normal conditions, sorcin slows I (Ca,L) inactivation because the effects of Ca(2+)-dependant inactivation out-weigh the effects on voltage-dependant inactivation.

Sorcin modulates cardiac L-type Ca2+ current by functional interaction with the alpha1C subunit in rabbits.

We examined the modulation of the cardiac L-type Ca(2+) channel (LTCC) by the regulatory protein sorcin and tested the hypothesis that modulation occurred by direct interaction. Whole-cell patch-clamp recordings were made on native rabbit ventricular myocytes and HEK 293 cells expressing cardiac alpha(1C) subunits. In ventricular cells, sorcin increased peak current when using either Ca(2+) or Ba(2+) as charge carriers. In HEK 293 cells, sorcin increased peak current density when using Ba(2+) as a charge carrier but not when using Ca(2+). In ventricular myocytes, current inactivation (tau(fast), in ms) was slowed by sorcin with Ca(2+) as the charge carrier, whilst in the presence of Ba(2+) it was enhanced. In HEK 293 cells, sorcin significantly enhanced tau(fast), but no significant change was observed with Ba(2+). This trend was mimicked by the truncated peptide, sorcin Ca(2+)-binding domain, which lacks the N-terminal domain. These data suggest that sorcin interacts with LTCC via its C-terminal domain, which alters current magnitude and tau(fast). These effects appear to be influenced by the prevailing experimental conditions.

Age and hypertrophy alter the contribution of sarcoplasmic reticulum and Na+/Ca2+ exchange to Ca2+ removal in rat left ventricular myocytes.

Age and hypertension contribute significantly to cardiac morbidity and mortality, however the importance of each during the progression of hypertrophy is unclear. This investigation examined the effect of age and hypertension on Ca(2+) handling in rat ventricular myocytes by comparing a genetic model of hypertension and cardiac hypertrophy (spontaneously hypertensive rat, SHR) with its normotensive control (Wistar-Kyoto rat, WKY) at 5 and 8 months of age. Experiments were performed on single left ventricular myocytes isolated from SHR or WKY hearts. Intracellular Ca(2+) was measured optically using fura-2 or fluo-3. SHR myocytes had a significantly larger cell width and volume and a significantly decreased cell length/width ratio at 5 and 8 months compared to normotensive controls. Age had no effect on cell length, width, volume or the length/width ratio. Ca(2+) transient amplitude, sarcoplasmic reticulum (SR) Ca(2+) content and contraction amplitude were unaffected by age or hypertrophy. However at 8 months the contribution of the SR to Ca(2+) uptake during relaxation decreased, with a concomitant increase in the contribution of Na(+)/Ca(2+) exchanger (NCX) function to relaxation, in SHR and WKY myocytes. The incidence of non-synchronous SR Ca(2+) release decreased with age but not hypertrophy in SHR and WKY myocytes. These results show that the changes in Ca(2+) handling observed during progression of mild hypertrophy in SHR are the same as those that occur during ageing in normotensive control animals and can, therefore, be ascribed to maturation rather than hypertrophy.

Cellular distribution of calcium current is unaltered during compensated hypertrophy in the spontaneously hypertensive rat.

Changes in cellular calcium (Ca(2+)) handling are thought to underlie the altered contraction that occurs during cardiac hypertrophy and failure. Recent work has highlighted the importance of t-tubules in the control of intracellular Ca(2+). The present study was performed to investigate whether changes in the distribution of I (Ca) between the surface and t-tubule membranes might contribute to the altered Ca(2+) handling observed during compensated hypertrophy in the spontaneously hypertensive rat (SHR). Experiments were performed on ventricular myocytes isolated from 5-month-old SHR and normotensive Wistar-Kyoto (WKY) control rats. Osmotic shock using formamide was used to disrupt the t-tubular system and the whole-cell patch clamp technique used to monitor I (Ca) in the presence and absence of t-tubules. Membrane capacitance and I (Ca) were greater in control SHR than WKY myocytes; following detubulation, cell capacitance and I (Ca) both decreased and were no longer significantly different in the two cell types. The density of I (Ca) was not significantly different in control SHR and WKY cells or in detubulated myocytes from the two species. These data suggest that the distribution of I (Ca) is unchanged in SHR myocytes compared to WKY controls; I (Ca) density in the t-tubules was 1.2-fold greater than in the sarcolemma in both strains. These data also imply that the increase in surface area in SHR myocytes is due principally to an increase in t-tubular area, which is accompanied by an approximately equivalent increase in I (Ca), so that the density of I (Ca) at the cell surface and in the t-tubules remains the same. These changes would be expected to retain cell function and synchronicity of Ca(2+) release in the SHR at this stage of compensated hypertrophy.

Decreased Ca2+ extrusion via Na+/Ca2+ exchange in epicardial left ventricular myocytes during compensated hypertrophy.

Hypertension-induced cardiac hypertrophy alters the amplitude and time course of the systolic Ca2+ transient of subepicardial and subendocardial ventricular myocytes. The present study was designed to elucidate the mechanisms underlying these changes. Myocytes were isolated from the left ventricular subepicardium and subendocardium of 20-wk-old spontaneously hypertensive rats (SHR) and age-matched normotensive Wistar-Kyoto rats (WKY; control). We monitored intracellular Ca2+ using fluo 3 or fura 2; caffeine (20 mmol/l) was used to release Ca2+ from the sarcoplasmic reticulum (SR), and Ni2+ (10 mM) was used to inhibit Na+/Ca2+ exchange (NCX) function. SHR myocytes were significantly larger than those from WKY hearts, consistent with cellular hypertrophy. Subepicardial myocytes from SHR hearts showed larger Ca2+ transient amplitude and SR Ca2+ content and less Ca2+ extrusion via NCX compared with subepicardial WKY myocytes. These parameters did not change in subendocardial myocytes. The time course of decline of the Ca2+ transient was the same in all groups of cells, but its time to peak was shorter in subepicardial cells than in subendocardial cells in WKY and SHR and was slightly prolonged in subendocardial SHR cells compared with WKY subendocardial myocytes. It is concluded that the major change in Ca2+ cycling during compensated hypertrophy in SHR is a decrease in NCX activity in subepicardial cells; this increases SR Ca2+ content and hence Ca2+ transient amplitude, thus helping to maintain the strength of contraction in the face of an increased afterload.

Mitochondrial Ca2+ transport in frog early distal tubule.

A global and transient rise of intracellular Ca2+ (Ca2+i) is central to the operation of pump-leak coupling in the frog early distal tubule (EDT). The endoplasmic reticulum (ER) is the site of this Ca2+ release and reuptake; however, it is likely that other intracellular pools, such as mitochondria, also contribute to cellular Ca2+ homeostasis. The present study was performed to seek evidence of mitochondrial Ca2+ transport in the frog EDT. Experiments were performed on isolated and permeabilized EDT segments from the frog kidney loaded with the low-affinity, Ca2+-sensitive fluorescent indicator, mag-fura-2. Ca2+ uptake in the absence of SarcoEndoplasmic Reticulum Calcium ATPase (SERCA) activity (inhibition by 2,5-di-t-butyl hydroquinone, TBQ) was evident at a bath [Ca2+] of 1 microm, but not at 200 nm, in the presence of ATP. This uptake was sensitive to the protonophore FCCP and the ATP-synthase inhibitor oligomycin. Ca2+ uptake was also stimulated by respiratory substrates; this uptake was enhanced by oligomycin and reversed by the application of FCCP. These findings provide the first evidence of mitochondrial Ca2+ transport in renal tubules, which appears to occur via a low-affinity pathway and which will act as a physiological Ca2+ buffer, protecting the cell from large increases in Ca2+i.

Functional consequences of detubulation of isolated rat ventricular myocytes.

OBJECTIVE: Recent work has suggested that Na(+)/Ca(2+) exchange (NCX) and L-type Ca(2+) current (I(Ca)) are located predominantly in the t-tubules of cardiac ventricular myocytes, which therefore represent a microdomain for the regulation of intracellular Na(+) (Na(i)) and Ca(2+) (Ca(i)). The aim of this study was to investigate the role of the t-tubules in the response of Ca(i) and contraction to interventions that alter the transsarcolemmal Na(+)gradient. METHODS: Enzymatically isolated and detubulated Wistar rat ventricular myocytes were investigated using fluorescence microscopy and optical detection of cell length. RESULTS: In unstimulated cells, spontaneous contractile activity increased when extracellular [Na(+)] was decreased or strophanthidin (100 microM) was added to the bathing solution, but the increase was significantly smaller in detubulated cells than in control cells. In electrically stimulated cells, strophanthidin increased Na(i) to a similar extent in normal and detubulated cells, although the associated increase in Ca(2+) transient amplitude and contraction were significantly smaller in detubulated cells. Similarly, tetrodotoxin (TTX, 10 microM) attenuated the Ca(2+) transient and contraction less in detubulated than in control cells. Increasing stimulation rate (0.05-1 Hz) caused little change or a small increase in contraction amplitude in control cells, but a significant decrease in contraction amplitude in detubulated cells, although the change of Na(i) caused by increasing stimulation rate from 0 to 1 Hz was not significantly different in the two cells types. CONCLUSION: It is concluded that although some Na/K ATPase, NCX and Na(+)channel activity is present on the surface membrane, the t-tubules play a major role in the modulation of contraction via NCX, allowing changes of the transsarcolemmal Na(+)gradient to be translated into changes of Ca(i).

Regulation and identity of intracellular calcium stores involved in membrane cross talk in the early distal tubule of the frog kidney.

The early distal tubule (EDT) of the frog nephron, similar to the thick ascending limb in mammals, mediates the transepithelial absorption of NaCl. The continued absorption of NaCl in the face of varying Na(+) load is maintained by coordination of the activity of ion-transporting proteins in the apical and basolateral membranes, so-called pump-leak coupling. Previous studies identified intracellular Ca(2+), originating from an intracellular Ca(2+) store, as playing a key role in pump-leak coupling in the EDT (Cooper GJ, Fowler MR, and Hunter M. Pflügers Arch 442: 243-247, 2001). The purpose of the experiments described in this paper was to identify the intracellular Ca(2+) storage pools in the renal diluting segment. Store Ca(2+) movements were monitored by the fluorescence of mag-fura 2 in permeabilized segments of frog EDTs. The presence of both ATP and Ca(2+) was required to maintain store Ca(2+) content. Removal of either of these substrates resulted in a passive leak of Ca(2+) from the stores. The uptake of Ca(2+) into the store was sensitive to the SERCA inhibitor 2,5-di(tert-butyl) hydroquinone, whereas Ca(2+) release from the store was stimulated by IP(3) but not cADPR. Store Ca(2+) was insensitive to the mitochondrial ATP synthase inhibitor oligomycin, and, under conditions that energized Deltapsi(m), the complex 1 inhibitor rotenone and the protonophore FCCP. Ionomycin was able to mobilize store Ca(2+) following exposure to IP(3). These results suggest that the endoplasmic reticulum is a dominant Ca(2+) store in the frog EDT. A second pool, sensitive to ionomycin but not IP(3), may overlap with the IP(3)-sensitve pool. The data also rule out any contribution by mitochondria to EDT Ca(2+) cycling.

Induction of cell division-related genes in quiescent (G0 ) sugar beet cells.

Sugar beet cells maintained in the stationary phase of the batch culture cycle for 2 or more days have been shown to exhibit many of the characteristics of quiescent (G0 ) cells. When such cells were subcultured into fresh medium they progressed through a period of DNA synthesis to a highly synchronised first division, 6 days after subculture. The onset of DNA synthesis and cell division were each delayed by 2 days relative to the timing of the events when the cells were subcultured immediately before entry into the stationary phase. The regulation of gene expression during this extended transition from the G0 phase back to the cell division cycle was investigated. The cell division cycle-related genes Bvcdc2, Betvu;CycA2, Arath;CycB1;1 histone H4 and Bvcrk1 (a novel cdc2-like gene) showed widely differing patterns of expression. Bvcdc2 transcripts were present at low levels in quiescent cells whereas crk1, cyclin and histone transcripts were not detectable. Expression of both Bvcrk1 and Betvu; CycA2 was induced within 1 h after subculture into fresh medium, whereas histone H4 gene expression was not detectable for 24 h and showed a marked increase between 24 and 48 h. B-type cyclin transcripts were not detectable until more than 48 h after subculture. The addition of either sucrose or MS macronutrients to quiescent sugar beet cells was not sufficient to re-initiate cell division but both medium components were able to stimulate the expression of the two 'early' genes (Betvu;CycA2 and Bvcrk1) within 6 h. Furthermore, although the sugar beet cells were habituated, i.e. they were routinely grown without added plant growth regulators, treatment of quiescent cells with IAA and kinetin also induced expression of Betvu;CycA2 and Bvcrk1 without subsequent cell division.