Search PubMed⌕ Search

Biomedical subjects

A Alfonso

Publications and source records attributed to A Alfonso.

At least 19 recordsLinked to original sources

Mast cell exocytosis can be triggered by ammonium chloride with just a cytosolic alkalinization and no calcium increase.

A human mast cell line (HMC-1) has been used to study the effect of cytosolic alkaline pH in exocytosis. Compound 48/80, concanavalin A, and thapsigargin do not induce histamine release in HMC-1 cells. Although thapsigargin does not activate histamine release, it does show a large increase in cytosolic Ca(2+), and no change in cytosolic pH. However, when HMC-1 cells were activated with ionomycin, a significant histamine release takes place, and this effect is higher in the presence of thapsigargin. Both drugs show an additive effect on cytosolic Ca(2+) levels. Ammonium chloride (NH(4)Cl) does activate cytosolic alkalinization and histamine release, with no increase in cytosolic Ca(2+). NH(4)Cl does block the release of internal Ca(2+) by thapsigargin, not by ionomycin, and decreases Ca(2+) influx stimulated by these drugs. Under conditions in which the alkalinization induced by NH(4)Cl is blocked by acidification with sodium propionate, histamine release is inhibited. The release of histamine is also observed when NH(4)Cl is added after propionate addition, regardless of the final pH value attained. Our results show that a shift in pH alkaline values, even with final pH below 7.2 is enough to activate histamine release. A shift to less acidic values is a sufficient signal to activate the cells.

Ammonium Chloride↗

Association of body size estimation and age in African-American females.

This cross-sectional research study tested the hypothesis that body image estimates of African-American females differ as a function of age. To test this hypothesis, body image estimates of 379 African-American females, ranging in age from 16 to 96 years, were contrasted as a function of age group, while statistically controlling body mass index. Three body size estimates, current body size, ideal body size, and reasonable body size were measured using the Body Image Assessment for Obesity. The discrepancies between current and ideal body size estimates and between current and reasonable body size estimates were also analyzed to assess for differences in body size dissatisfaction. The study found that younger African-American women (16 to 35 years) differed from older African-American women (>35 years) on measures of body size dissatisfaction. Women in the age range of 26 to 35 years reported higher estimates of current body size in comparison to women older than 35 years. The youngest age group (16 to 25 years) reported thinner ideal body size goals in comparison to women who were slightly older (26 to 35 years) and women who were older than 75 years. The pattern of body image estimates across a large age range suggests that younger African-American women, in comparison to older African-American women, may have body images that may make them more susceptible to eating disorders.

Adolescent↗

Efficacy of an internet-based behavioral weight loss program for overweight adolescent African-American girls.

OBJECTIVE: This randomized controlled trial tested the efficacy of an internet-based lifestyle behavior modification program for weight management in African-American girls. DESIGN: African-American girls were randomly assigned to an interactive behavioral internet program or an internet health education program, the control condition. The behavioral intervention included internet counseling and was highly interactive. The control intervention was a passive (non-interactive) educational program. Parents were also participants in the study. Participants in both treatment groups met in face-to-face sessions on four occasions over the first 12 weeks of a 6-month intervention. SUBJECTS: The study enrolled 57 African-American adolescent girls (ages 11 to 15 years) who were overweight or obese and had at least one biological parent who was obese [body mass index (BMI) >30 kg/m2]. Of the 57 participants, 50 (88%) completed the 6-month trial. MEASUREMENTS: Outcome data, including BMI, body weight, body composition, dietary intake, and weight loss behaviors were collected at baseline and 6-months later. A computer server tracked utilization of the websites. Participation in the program was measured by number of "hits" on the website. RESULTS: Compared to the control condition, adolescents in the behavioral treatment lost more body fat (group difference =1.6% body fat) and parents lost significantly more body weight (group difference =2.1 kg). Utilization of the behavioral website by adolescents and parents was associated with positive outcome. Dietary fat intake was lowered for adolescents and parents in the behavioral treatment group. CONCLUSION: An internet-based behavioral intervention was superior to internet-based health education and yielded decreased body fat for adolescent girls and decreased body weight for parents.

Absorptiometry, Photon↗

Percent body fat measured by BIA and DEXA in obese, African-American adolescent girls.

OBJECTIVE: To compare the estimation of body fat between bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DEXA) in overweight, African-American female adolescents. SUBJECTS: In total, 54 African-American adolescent female subjects were recruited for Study 1. Each adolescent's body mass index was greater than the 85th percentile and their average body fat was 45% according to DEXA. A total of 26 African-American adolescent female subjects were available for Study 2, and had an average body fat of 26% according to DEXA. MEASUREMENTS: Percent body fat was measured by DEXA and BIA. Seven different BIA equations were tested. Both sets of data were analyzed using Bland-Altman regression analyses, utilizing percent body fat measured by DEXA as the criterion. RESULTS: The Kushner equation provided estimates that were unaffected by body fat in both studies. Estimates were unbiased when applied to the exclusively overweight sample and biased when utilized with the separate sample of normal weight and obese girls. The remaining equations were biased, provided inconsistent estimates across body weight, or were biased and provided inconsistent estimates. Ethnicity-specific and ethnicity-combined equations performed similarly in the obese sample, but became more disparate when applied to a sample encompassing a wider body weight range. The limits of agreement between all BIA equations and the DEXA estimates ranged from 6 to 9%. CONCLUSION: The study suggests that the Kushner BIA equation is appropriate for use with African-American female adolescents across the weight spectrum, while the majority of BIA equations underestimated percent body fat as body fat increased.

Absorptiometry, Photon↗

Calcium-pH crosstalks in rat mast cells: modulation by transduction signals show non-essential role for calcium in alkaline-induced exocytosis.

Alkalinization of cytosolic pH with ammonium chloride (NH4Cl) was reported to be a stimulus for mast cell degranulation. This paper studied the modulatory role of drugs that target protein kinase C (PKC), adenosine 3',5'-cyclic monophosphate (cAMP), tyrosine kinase (TyrK) and phosphatidylinositol 3-kinase (PI3K) on this effect. We used Go6976 (100 nM) and low concentrations of GF109203X (Gf) (50 nM) to inhibit calcium-dependent PKC isozymes. For calcium-independent isozymes, we used 500 nM Gf, and 10 microM rottlerin to specifically inhibit PKC delta, and chelerythrine as non-specific PKC inhibitor. Genistein (10 microM) and lavendustin A (1 microM) were used as unspecific TyrK inhibitors, and 10 nM wortmannin as a PI3K inhibitor. Chelerythrine and 50 nM Gf inhibit histamine release in the presence of external calcium. The inhibition caused by wortmannin was strictly internal calcium-dependent. cAMP-active drugs did not modify the response to NH4Cl. The effect of NH4Cl on histamine release was triggered by a transient elevation on cytosolic pH, which was simultaneous to an elevation on cytosolic calcium and followed by a probable Ca2+-H+ exchange after addition of external calcium. EGTA inhibit the response to suboptimal concentrations of NH4Cl, and BAPTA increased the effect of NH4Cl. There is a clear relationship between NH4Cl-mediated calcium release and histamine release, since those drugs that inhibit this release also inhibit NH4Cl-mediated histamine release; nevertheless, NH4Cl-mediated histamine release was possible in the absence of any calcium release, as shown with BAPTA. This data, in combination with the results with PKC inhibitors, suggest that calcium is not only unnecessary to trigger cell activation, but also that it may be a negative modulator of NH4Cl-mediated exocytosis.

Alkalies↗

Digital photography: a new method for estimating food intake in cafeteria settings.

OBJECTIVE: The primary objective of this study was to test the comparability of digital photography and visual estimation procedures for estimating food intake. RESEARCH METHODS AND PROCEDURES: The study sample included 71 breakfast meals and 59 lunch meals eaten in a university cafeteria during a single day. A total of 66 different foods were employed as test foods that could be selected by the students. Food selections and plate waste, as estimated by digital photography and visual estimation, were compared. For digital photography, three observers independently estimated portion sizes of each food item based upon digital photographs. One observer estimated portion sizes in the cafeteria setting, using visual estimation, a method that has been validated in other studies. RESULTS: To test the accuracy of the two procedures for measuring food intake, the estimates of food weights derived from both procedures were compared using Bland-Altman regression. In comparison to visual estimation, the digital photography method yielded comparable estimates of food selections, plate waste, and total food intake for seven of nine comparisons. The two methods of estimating food portions yielded comparable results for most (78%) types of foods. The two methods also yielded similar variability. DISCUSSION: These findings suggest that the digital photography method is an alternative to the traditional method of estimating food intake via direct observation.

Energy Intake↗

Dimethylsphingosine increases cytosolic calcium and intracellular pH in human T lymphocytes.

N,N-Dimethyl-D-erythro-sphingosine (DMS) is the N-methyl derivative of sphingosine; both are activators of sphingosine-dependent protein kinases. The aim of this work was to study the effect of DMS on cytosolic calcium and intracellular pH (pHi) in human T lymphocytes. The variations of calcium and pH were determined by fluorescence digital imaging using Fura-2-AM and BCECF-AM, respectively. DMS increased both pHi and Ca(2+)-cytoslic in human T lymphocytes. These effects were dose-dependent. This drug induced a fast increase in pHi and a release of calcium from different intracellular calcium pools than thapsigargin. DMS also induced a Ca(2+)-influx different from the store-operated calcium channels, since drug effect was not modified by 30 microM SKF 96365. The influx of calcium induced by DMS was completely blocked by preincubation in the presence of nickel, or lanthanum, while the increase in pHi was no affected. However, the presence of cadmium reduced but does not block Ca(2+)-influx. The inhibition of G-protein by 100 ng/mL pertussis toxin, and the inhibition of tyrosine kinases by genistein significantly reduced the cytosolic calcium increase induced by DMS by an inhibition of both, release of calcium from intracellular pools and influx from extracellular medium. The inhibition of pools emptiness by these drugs was related with the inhibition that they induce in the DMS cytosolic alcalinization. In summary, DMS increases pHi and as consequence releases calcium from intracellular pools, and it increases calcium-influx through a channel different from store-operated channel (SOC). Both cytosolic calcium and pHi increase are modulated by G-proteins and tyrosine kinases.

Calcium↗

Modulation of cytosolic calcium levels of human lymphocytes by yessotoxin, a novel marine phycotoxin.

Yessotoxin (YTX) is a polyether toxin of marine origin that has been classified among the diarrheic shellfish poisoning (DSP) toxins group due to its lipophilic nature. However, unlike other DSP toxins, YTX does not produce diarrhea and its mechanisms of action are unknown. We studied the effect of YTX on the cytosolic calcium levels of freshly isolated human lymphocytes by means of fluorescence imaging microscopy. We showed that YTX produced a calcium influx through nifedipine and SKF 96365 (1-[beta-[3-(4-methoxyphenyl)propoxyl]-4-methoxyphenyl]-1H-imidazole hydrochloride)-sensitive channels. This Ca2+ entry was not affected by the DSP toxin okadaic acid, which inhibits protein phosphatases. In addition, YTX also produced an inhibition of capacitative calcium entry activated by thapsigargin or by preincubation in a Ca2+-free medium. This capacitative calcium entry was not sensitive to nifedipine. Furthermore, the inhibitory effect of YTX was dependent on the time of addition of the toxin. We suggest that YTX may interact with calcium channels in a way similar to that described for other polyether marine compounds such as brevetoxins and maitotoxin, although an involvement of other second messengers is also likely.

Biological Transport↗

Confocal microscopy study of the different patterns of 2-NBDG uptake in rabbit enterocytes in the apical and basal zone.

D-Glucose uptake in isolated rabbit enterocytes was studied using confocal microscopy and 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-D-glucose (2-NDBG), a D-glucose fluorescent analogue, by analysing the fluorescence of apical and basal enterocyte zones. Under normal conditions, apical fluorescence was always higher than basal, presumably due to the location of the Na+-D-glucose cotransporter in the brush-border membrane. After blocking this transporter with phlorizin, apical and basal fluorescence values were similar. This suggests that both brush-border and basolateral membranes participate in phlorizin-insensitive D-glucose transport, since transport across only one membrane cannot explain the uniform overall fluorescence observed. Similarly, after inhibiting the Na+-D-glucose cotransporter by incubating the enterocytes in a medium containing 0.5 mM Na+, neither apical nor basal fluorescence predominated. In contrast, with 130.5 mM extracellular Na+, apical fluorescence was clearly higher than basal fluorescence. These results suggest that phlorizin-insensitive, Na+-independent 2-NDBG uptake occurred through both brush-border and basolateral membranes, probably via the glucose uniporters GLUT2 and GLUT5, suggesting that the latter is a D-glucose transporter.

4-Chloro-7-nitrobenzofurazan↗

Pyrazolopyrimidines: synthesis, effect on histamine release from rat peritoneal mast cells and cytotoxic activity.

A series of 1H-pyrazolo[3,4-d]pyrimidines (3--6) substituted at positions 1 (R(1)=Ph, H, tert-butyl and ribosetribenzoate), 4 (R(2)=chlorine, nitrogen and oxygen nucleophiles), and 6 (dimethylamino) have been synthesized and their effect on the release of histamine from rat peritoneal mast cells measured. After chemical stimulation, (polymer 48/80), several compounds (i.e. 3b, 4a, 4b, 4d, 4g, 5a), produce inhibition two to three times higher (40--60%) than DSCG but this action is lower after preincubation. 4b (R(1)=Ph, R(2)=NHCH(2)Ph; 50--70% inhibition) and 5a (R(1)=H, R(2)=OMe; 50--55% inhibition) are the most active ones in both experiments. With ovoalbumin as stimulus, several pyrazolopyrimidines show inhibition similar to DSCG, the most active compounds being 6a--d (IC(50)=12--16 microM; R(1)=ribosetribenzoate, R(2)=methoxy and amino). Compounds 4e (R(1)=t-butyl, R(2)=OMe) and 4g (R(1)=t-butyl, R(2)=piperidino) are inducers of the release of histamine (60 and 150% increase). Compounds 4b and 4c showed cytotoxic activity (IC(50)=1 microg/mL) to HT-29 human colon cancer cells.

Animals↗

Ouabain-induced enhancement of rat mast cells response. Modulation by protein phosphorylation and intracellular pH.

The digitalic glicoside ouabain induces potentiation of rat mast cell histamine release in response to several stimuli, which is mediated by Na+/Ca2+ exchanger. In this work, we studied the effect of ouabain on cytosolic calcium, intracellular pH and histamine release with Ca2+ ionophore A23187 in conditions designed to maximize ouabain-induced potentiation of rat mast cells response. The effect of protein kinase C (PKC), cAMP and phosphatase inhibition was also tested. Ouabain induced an enhancement in histamine release, cytosolic calcium and intracellular pH. The adenylate cyclase activator forskolin reduced the effect of ouabain on histamine release and intracellular pH, but enhanced the effect on cytosolic calcium. PKC activator PMA enhanced the effect of ouabain on histamine release and cytosolic calcium, without affecting intracellular pH. A PKC inhibitor, GF-109203X, reduced ouabain-induced enhancement of histamine release and intracellular pH, but increased the enhancement on cytosolic calcium. Finally, inhibition of protein phosphatases 1 and 2A with okadaic acid, increased the effect of ouabain on histamine release and intracellular pH, but reduced cytosolic calcium in presence of ouabain. This result suggest that ouabain-induced potentiation of rat mast cell histamine release with A23187 is modulated by kinases, and this modulation may be carried out by changes in intracellular alkalinization. However, the mechanism underlying cellular alkalinization remains to be elucidated.

Animals↗

Maitotoxin-induced calcium entry in human lymphocytes: modulation by yessotoxin, Ca(2+) channel blockers and kinases.

We have studied the effect of the ciguatera-related toxin maitotoxin (MTX) on the cytosolic free calcium concentration ([Ca(2+)]i) of human peripheral blood lymphocytes loaded with the fluorescent probe Fura2 and the regulation of MTX action by different drugs known to interfere in cellular Ca(2+) signalling mechanisms and by the marine phycotoxin yessotoxin (YTX). MTX produced a concentration-dependent elevation of [Ca(2+)]i in a Ca(2+)-containing medium. This effect was stimulated by pretreatment with YTX 1 microM and NiCl(2) 15 microM. The voltage-independent Ca(2+) channel antagonist 1-[beta-[3-(4-methoxyphenyl)propoxyl]-4-methoxyphenyl]-1H-imidazole hydrochloride (SKF96365) blocked the MTX-induced [Ca(2+)]i elevation, while the L-type channel blocker nifedipine had no effect. Pretreatment with NiCl(2) or nifedipine did not modify YTX-induced potentiation of MTX effect, and SKF96365-induced inhibition was reduced in the presence of YTX, which suggest different pathways to act on [Ca(2+)]i. Preincubation with N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide.2HCl (H-89) or genistein (10 microM) also had no effect on the MTX-induced [Ca(2+)]i increment. In contrast, the PKC inhibitor bisindolilmaleimide I (GF109203X 1 microM) potentiated the MTX effect, whereas phosphatidylinositol (PI) 3-kinase inhibition with wortmannin (10 nM) reduced the MTX-elicited Ca(2+) entry. In summary, MTX produced Ca(2+) influx into human lymphocytes through a SKF96365-sensitive, nifedipine-insensitive pathway. The MTX-induced [Ca(2+)]i elevation was stimulated by the marine toxin YTX through a mechanism insensitive to SKF96365, nifedipine or NiCl(2). It was also stimulated by the divalent cation Ni(2+) and PKC inhibition and was partially inhibited by PI 3-kinase inhibition.

Calcium↗

Prolactin induces calcium influx and release from intracellular pools in human T lymphocytes by activation of tyrosine kinases.

The early events related to intracellular signals after prolactin (PRL) activation in T lymphocytes are not clearly established. The aim of this work was to study the effect of PRL in cytosolic calcium levels in human T lymphocytes. By using the dye FURA-2 AM, the variations in cytosolic Ca(2+) were studied in peripheral human T lymphocytes isolated from extracted blood from healthy donors. Fifty nanograms per milliliter PRL induces a small increase in cytosolic calcium. When the cells are preincubated overnight (16-20 h) in the presence of PRL, the increase in calcium is higher. This high increase is due to the release from intracellular pools and to the influx from the extracellular media. That is, after overnight incubation with PRL, calcium influx in T cells follows the capacitative model. Since PRL receptor (PRL-R) activation involves the tyrosine kinase pathway, we check calcium effect in the presence of genistein, a known inhibitor of tyrosine kinases. When cells are preincubated in the presence of 10 microM genistein, and PRL is immediately added, no increase in cytosolic calcium is observed. The presence of genistein also completely blocks the increase in cytosolic calcium stimulated by PRL after overnight incubation with PRL. In the presence of PRL and N,N-dimethyl-D-erythro-sphingosine (DMS), a stimulus that increases cytosolic calcium in T cells by tyrosine kinase stimulation, a high, even insignificant, calcium influx is induced. However, when the cells are incubated overnight in the presence of PRL, and then DMS is added, a significant increase in cytosolic calcium levels takes place. This increase is associated with an increase in calcium release from intracellular pools and an increase in calcium uptake. Genistein reduces the influx of external calcium induced by DMS after short incubation with PRL and significantly inhibits both, calcium pools empty, and calcium influx is induced by DMS after overnight incubation with PRL. In summary, PRL induces calcium influx in normal T lymphocytes. The influx is magnified after long PRL exposures, intracellular Ca(2+) pool-dependent, and activated through tyrosine kinases.

Calcium↗

Hypertonicity-induced intracellular pH changes in rat mast cells.

In a non-isotonic environment, cells can shrink or swell and return to their normal shape by activating ion transport pathways. Changes in intracellular pH (pHi) after osmotic stress have been identified in several cells. In order to study the mechanisms that regulate cytosolic pH of rat mast cells in a hypertonic medium, we used the pH sensitive dye, BCECF. Under these hypertonic conditions, pHi undergoes an alkalinization following an initial acidification. The alkalinization is mediated by a Na+/H+ exchanger, since it is inhibited by amiloride and lack of extracellular sodium. Under these conditions, the alkalinization is increased with the PKC activators, TPA and OAG, and partially blocked with trifluoperazine, an unspecific protein kinase C (PKC) and Ca2+ calmodulin-dependent protein kinases (Ca2+/CaM K) inhibitor. There is also an anion exchanger, blocked with DIDS but not activated by PKC, that participates in the observed alkalinization. However, Na+/H+ exchanger is the main mechanism involved in the alkalinization of pHi of mast cells in a hyperosmotic environment.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗

Functional compartments in rat mast cells for cAMP and calcium on histamine release.

The crosstalk between 3', 5'-cyclic adenosine monophosphate (cAMP), intracellular calcium, and histamine release in rat mast cells using the stimulatory effect of three different drugs, thapsigargin, sodium fluoride (NaF), and compound 48/80 were studied. Each of these drugs induces histamine release by different mechanisms. The transducting pathways modulating cAMP and intracellular calcium levels were modified by using, cholera toxin (CTX) which ADP-rybosylates Gs-protein, pertussis toxin (PTX) which ADP-rybosylates Gi-protein, and okadaic acid (OA) which inhibits phosphatases 1 and 2a. Our results show that CTX increased cAMP levels and inhibited histamine release elicited by thapsigargin and compound 48/80. The inhibitory effect of CTX on histamine release was potentiated by OA in the presence of compound 48/80 but was decreased in the presence of thapsigargin. Calcium uptake was stimulated by NaF and compound 48/80. The previous treatment with OA increased calcium uptake when combined with compound 48/80 but not with NaF. Treatment with NaF highly stimulated calcium uptake and cAMP levels only when combined with OA and CTX. These results suggest that the modulatory effect of intracellular calcium and cAMP on histamine release depend more on the crosstalk of the activated signal transducting pathway than on the final level of calcium or cAMP, further supporting the theory that rat mast cells are divided into functionally distinct compartments.

Animals↗

Crosstalk between cytosolic pH and intracellular calcium in human lymphocytes: effect of 4-aminopyridin, ammoniun chloride and ionomycin.

Stimulation of lymphocytes by specific antigens is followed by the activation of different signal transduction mechanisms, such as alterations in the cytoplasmic levels of Ca(2+), H(+) and variations in membrane potential. To study interrelationships among these parameters, changes in pHi and Ca(2+) were measured with the fluorescent probes BCECF and Fura-2 in freshly isolated blood human lymphocytes. Moreover, membrane potential qualitative alterations were recorded with the fluorescent dye bis-oxonol. In a bicarbonate-free medium, cell alkalinization with NH(4)Cl slightly decreased intracellular Ca(2+) concentration ([Ca(2+)](i)) due to efflux of Ca(2+) from the cell. In contrast, an elevation of pHi induced with 4-AP increased [Ca(2+)](i), either in the presence or absence of external Ca(2+). The increase in Ca(2+)-free medium is likely to be due to Ca(2+) release from thapsigargin and caffeine-independent intracellular stores. Both 4-AP or NH(4)Cl induced a plasma membrane depolarisation, although with different kinetics. The ionosphere ionomycin increased pHi, Ca(2+) levels and also induced membrane depolarisation. Together, these observations demonstrate a lack of correlation between the magnitude of changes in pHi and Ca(2+).

4-Aminopyridine↗

Calcium-pH crosstalks in rat mast cells: cytosolic alkalinization, but not intracellular calcium release, is a sufficient signal for degranulation.

The aim of this work was to study the relationship between intracellular alkalinization, calcium fluxes and histamine release in rat mast cells. Intracellular alkalinization was induced by nigericin, a monovalent cation ionophore, and by NH(4)Cl (ammonium chloride). Calcium cytosolic and intracellular pH were measured by fluorescence digital imaging using Fura-2-AM and BCECF-AM. In rat mast cells, nigericin and NH(4)Cl induce a dose-dependent intracellular alkalinization, a dose-dependent increase in intracellular calcium levels by releasing calcium from intracellular pools, and an activation of capacitative calcium influx. The increase in both intracellular calcium and pH activates exocytosis (histamine release) in the absence of external calcium. Under the same conditions, thapsigargin does not activate exocytosis, the main difference being that thapsigargin does not alkalinize the cytosol. After alkalinization, histamine release is intracellular-calcium dependent. With 2.5 mM EGTA and thapsigargin the cell response decreases by 62%. The cytosolic alkalinization, in addition to the calcium increase it is enough signal to elicit the exocytotic process in rat mast cells.

Ammonium Chloride↗

Severe necrotizing mastopathy caused by calciphylaxis alleviated by total parathyroidectomy.

Calciphylaxis is a complication caused by secondary hyperparathyroidism in patients with chronic renal failure. These patients may present with clinical findings of ischemic necrosis involving the skin and muscle resulting in subsequent gangrene and vascular calcifications. We report a rare case of necrotizing mastopathy caused by calciphylaxis in a 70-year-old female with end-stage renal disease whose symptoms resolved with a total parathyroidectomy.

Aged↗