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The silkworm (Bombyx mori) has long been valued food and feed in East Asia for its abundant nutritional and medicinal attributes, conversely, it can elicit allergic responses in susceptible individuals. Therefore, the development of silkworm detection method is required to avert allergenic incidents. In this study, two methodologies, tandem mass spectrometry (LC-MS/MS) and real-time PCR, were developed to achieve effective silkworm detection. These methods exhibited exceptional sensitivity in identifying silkworm presence in processed foods. Furthermore, model cookies spiked with silkworm were used to validate the sensitivities of LC-MS/MS (0.0005%) and real-time PCR (0.001%). Overall, these techniques were useful for trace silkworm detection in food products; therefore, they may help prevent allergic reactions. To the best of our knowledge, this study represents the first comparison of LC-MS/MS and real-time PCR methods for silkworm detection, marking an important contribution to the field. Data are available from ProteomeXchange under identifier PXD042494., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The sugar beet is the second-largest sugar-producing crop. Genetically modified (GM) sugar beet, which have herbicide-resistant, have been developed to increase production and comprise over 90% of the market share. This study describes qualitative and quantitative PCR methods for the GM sugar beet H7-1 with reference plasmid (pUC_GM-SB) containing an endogenous gene ( GS2 ) and an event-specific gene for H7-1 that served as a positive control for PCR. The detection limit of qualitative PCR was approximately 10 copies of the reference plasmid and 0.05% in spiked samples. In the case of quantitative PCR, the detection limit was five copies of the reference plasmid. Regarding repeatability, the standard deviation and relative standard deviation were found to range from 0.11 to 0.24 and from 0.23% to 0.99%, respectively. This study provides food safety assurance for imported GM sugar beet H7-1 using the reference plasmid and supports efficient detection methods., Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-024-01572-6., Competing Interests: Conflict of interestOn behalf of all authors, the corresponding author states that there is no conflict of interest., (© The Korean Society of Food Science and Technology 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

The BCL2 inhibitor venetoclax promotes apoptosis in blood cancer cells and is approved for treatment of chronic lymphocytic leukemia and acute myeloid leukemia. However, multiple myeloma cells are frequently more dependent on MCL-1 for survival, conferring resistance to venetoclax. Here we report that mevalonate pathway inhibition with statins can overcome resistance to venetoclax in multiple myeloma cell lines and primary cells. In addition, statins sensitize to apoptosis induced by MCL-1 inhibitor, S63845. In retrospective analysis of venetoclax clinical studies in multiple myeloma, background statin use was associated with a significantly enhanced rate of stringent complete response and absence of progressive disease. Statins sensitize multiple myeloma cells to venetoclax by upregulating two proapoptotic proteins: PUMA via a p53-independent mechanism and NOXA via the integrated stress response. These findings provide rationale for prospective testing of statins with venetoclax regimens in multiple myeloma., Significance: BH3 mimetics including venetoclax hold promise for treatment of multiple myeloma but rational combinations are needed to broaden efficacy. This study presents mechanistic and clinical data to support addition of pitavastatin to venetoclax regimens in myeloma. The results open a new avenue for repurposing statins in blood cancer., (© 2023 The Authors; Published by the American Association for Cancer Research.)

Selective depolymerization of lignin remains a significant challenge in biomass conversion. The biosynthesis of lignin involves the polymerization of monolignol building blocks through oxidative radical coupling reactions. A strategy for lignin degradation leverages photoredox deoxygenative radical formation to trigger reverse biosynthesis, which cleaves model compounds of the β-O-4 and β-5-β-O-4 linkages to produce monolignols, precursors to flavoring compounds. This mild method preserves important oxygen functionality and serves as a platform for achieving selective lignin depolymerization.

Genetically modified organisms (GMOs) have been continuously developed for their convenience and productivity. In the past three years, three new GM canola events (MON94100, LBFLFK, and NS-B50027-4) have been developed. To efficiently control these GM canola events, the detection methods were needed. Therefore, the multiplex PCR method combined with capillary electrophoresis was developed for three GM canola events. Ten GM canola, eighteen GM soybean, thirty-two GM maize, and ten non-GM crops were used to evaluate the specificity of the method. The detection limit of the multiplex PCR assay was determined to be 0.005 ng in the DNA mixture and 0.1% in the spiked sample. The aim of this study was to establish multiplex PCR coupled with capillary electrophoresis for the newly produced three GM canola events. The developed method is expected to contribute to monitor the commercially available GM canola events., Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01377-z., Competing Interests: Conflict of interestOn behalf of all authors, the corresponding author states that there is no conflict of interest., (© The Korean Society of Food Science and Technology 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

This study investigated whether misalignment between an individual and their community in partisan identity predicted psychological and behavioral distancing from local COVID-19 norms. A nationally representative sample of Republicans and Democrats provided longitudinal data in April ( N = 3,492) and June 2020 ( N = 2,649). Democrats in Republican communities reported especially heightened better-than-average estimates , perceiving themselves as more adherent to and approving of non-pharmaceutical interventions (NPI; e.g., mask wearing) than their community. Democrats' better-than-average estimates reflected high approval and behavior in Republican communities and substantial norm underestimation. Republicans in Democratic communities did not evidence worse-than-average estimates . In longitudinal models, injunctive norms only predicted NPI behavior when individual and community partisan identity were aligned. The strong personal approval-behavior association did not depend on misalignment; there were no effects of descriptive norms. Normative messages may have limited efficacy for a sizable subpopulation in politically polarized contexts, such as the COVID-19 pandemic., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Centipedes contain pharmacologically active compounds used as important medicinal material. However, the poisons produced by centipedes can cause human diseases; therefore, its use as a food ingredient is prohibited. This is the first report to develop a real-time PCR method for detection of centipedes. The primer and probe targeting the mitochondrial cytochrome c oxidase subunit 1 (COI) gene were newly designed. The specificity was verified using ten species and was confirmed to amplify only the centipede species. The real-time PCR method exhibited good linearity with a high-determination coefficient ( R 2  = 0.999) and a detection limit was 0.001 ng. The performance of our method was also verified using five real-time PCR platforms under Universal and Fast PCR conditions. Finally, its applicability to processed food was evaluated using binary insect mixtures, and at least 0.1% of centipedes was detected. Therefore, our method can specifically and sensitively detect centipedes in food, contributing to food safety., Competing Interests: Conflict of interestOn behalf of all authors, the corresponding author states that there is no conflict of interest., (© The Korean Society of Food Science and Technology 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Droplet digital polymerase chain reaction (ddPCR) is one of the newest and most promising tools providing absolute quantification of target DNA molecules. Despite its emerging applications in microorganisms, few studies reported its use for detecting lactic acid bacteria. This study evaluated the applicability of a ddPCR assay targeting molecular genes obtained from in silico analysis for detecting Lactiplantibacillus plantarum subsp. plantarum, a bacterium mainly used as a starter or responsible for fermentation in food. The performance characteristics of a ddPCR were compared to those of a quantitative real-time PCR (qPCR). To compare the linearity and sensitivity of a qPCR and ddPCR, the calibration curve for a qPCR and the regression curve for a ddPCR were obtained using genomic DNA [102−108 colony-forming units (CFU)/mL] extracted from a pure culture and spiked food sample. Both the qPCR and ddPCR assays exhibited good linearity with a high coefficient of determination in the pure culture and spiked food sample (R2 ≥ 0.996). The ddPCR showed a 10-fold lower limit of detection, suggesting that a ddPCR is more sensitive than a qPCR. However, a ddPCR has limitations in the absolute quantitation of high bacterial concentrations (>106 CFU/mL). In conclusion, a ddPCR can be a reliable method for detecting and quantifying lactic acid bacteria in food.

There is a need to identify the species of similar types of fish, especially those that are commercially sold. Particularly, the price of tuna varies depending on its type, which is difficult to determine as they are sold in cut or processed forms. This study developed a multiplex polymerase chain reaction (PCR) assay to identify the five most common tuna species: bigeye, skipjack, Atlantic bluefin, albacore, and yellowfin tunas. Newly designed species-specific primer sets for these five tuna species were created. Subsequently, the amplicon sizes obtained were 270, 238, 200, 178, and 127 base pairs for bigeye, skipjack, Atlantic bluefin, albacore, and yellowfin tunas, respectively. Each primer's specificity was further tested using 15 other fish species, and no cross-reactivity was observed. To identify multiple targets in a single reaction, multiplex PCR was optimized to increase its resolution and accuracy. The detection levels of the multiplex PCR assay were confirmed to be 1 pg for all the five tunas. Additionally, it was successfully applied to 32 types of commercial tuna products. Therefore, this multiplex PCR assay could be an efficient identification method for various tuna species.

The impact of climate change on social conflict and violence is of increasing concern. The significant risk that climate change poses for human conflict has driven scholars to investigate the processes underlying the relationship. Although climate change may not directly cause conflict, heat waves and extreme weather events could amplify interpersonal violence, and climate change consequences (i.e. economic deprivation and migration) could also intensify intergroup conflict. However, psychological research is weakly integrated with this literature, and interdisciplinary efforts are needed to uncover the underpinnings of the relationship between climate change and conflict. In particular, psychological research on intergroup threat, climate change mitigation and adaptation, and culture can provide valuable insights into understanding and responding to climate-induced conflict., Competing Interests: Conflict of interest statement Nothing declared., (Copyright © 2021. Published by Elsevier Ltd.)

With an increasing interest and demand for biotechnology crops in agriculture worldwide, genetically modified (GM) breeding stacks produced by conventional breeding of previously approved GM single events remain popular for farmers in GM crop cultivation countries. However, regulations on stacks vary in each country. Currently, Korea requires approval for all breeding stacks intended for cultivation. To determine whether the stack is subject to a full safety assessment as a new GM crop, molecular characterization, protein expression, composition analysis, and agronomic characterization data are required. Korea's regulatory policy on stacks has not adopted the high-covers-low concept; therefore, subcombinations of already approved higher combination events are subject to breeding stack review if any subcombination was purposefully bred for cultivation use. This review will help promote the efficient management of GM breeding stacks in Korea in the future., Competing Interests: Conflicts of interestThe authors declare no conflict of interest., (© The Korean Society of Food Science and Technology 2021.)

Increased demand for nurses and improved technology have increased the development and popularity of online education programs over the past two decades; however, the online format has revealed numerous pedagogical and implementation challenges. One primary challenge is the lack of structural design standards across all courses in the program. The lack of standardization is linked to decreased student outcomes, satisfaction, and retention. The Quality Matters course design rubric and program certification provide a methodical process to standardize the format of all courses in an online education program. The Quality Matters course rubric is designed to increase student and faculty engagement and reduce variability in course design. At the current university, the application of Quality Matters processes and standards was first trialed with a few individual courses. Following the trial, faculty and administration decided to begin the process of seeking Quality Matters certification for the entire registered nurse-bachelor of science in nursing program. This article describes the process of attaining Quality Matters program certification for an online registered nurse-bachelor of science in nursing program. The nursing process and the Human Performance Technology evaluation model were used as appraisal frameworks guiding this program's QM certification process., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

To provide consumers correct information on meat species, specific and sensitive detection methods are needed. Thus, we developed a capillary electrophoresis-based multiplex PCR assay to simultaneously detect red deer ( Cervus elaphus ), roe deer ( Capreolus capreolus ), and water deer ( Hydropotes inermis ). Specific primer sets for these three species were newly designed. Each primer set only amplified target species without any reactivity against non-target species. To identify multiple targets in a single reaction, multiplex PCR was optimized and combined with capillary electrophoresis to increase resolution and accuracy for the detection of multiple targets. The detection levels of this assay were 0.1 pg for red deer and roe deer and 1 pg for water deer. In addition, its applicability was demonstrated using various concentrations of meat DNA mixtures. Consequently, as low as 0.1% of the target species was detectable using the developed method. This capillary electrophoresis-based multiplex PCR assay for simultaneous detection of three types of deer meat could authenticate deer species labeled on products, thus protecting consumers from meat adulteration.

Tropomyosin present in mollusk species is the most common allergen in humans and causes excessive immune responses. To simultaneously detect tropomyosin allergens in mollusk species, a multiplex PCR assay combined with capillary electrophoresis was developed for the detection of tropomyosin genes of oyster, mussel, abalone, and clam, and the 18S rRNA gene of eukaryotes. The developed multiplex PCR revealed specific amplicons of four mollusk species [oyster (Crassostrea gigas), 150 bp; mussel (Mytilus edulis), 119 bp; abalone (Haliotis discus hannai), 98 bp; clam (Ruditapes philippinarum), 76 bp] and an amplicon of universal eukaryotic primer (eukaryotes, 190 bp); the detection limit of DNA was confirmed to be 16 pg. This multiplex PCR assay was applied for monitoring commercially processed seafood products, achieving successful detection of tropomyosin genes in 19 processed seafood products in Korea. The developed assay is an efficient and useful method for detecting tropomyosin allergens from mollusk species in seafoods., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Placing a double-lumen endobronchial tube (DLT) in an appropriate position to facilitate lung isolation is essential for thoracic procedures. The novel ANKOR DLT is a DLT developed with three cuffs with a newly added carinal cuff designed to prevent further advancement by being blocked by the carina when the cuff is inflated. In this prospective study, the direction and depth of initial placement of ANKOR DLT were compared with those of conventional DLT. Patients undergoing thoracic surgery ( n = 190) with one-lung ventilation (OLV) were randomly allocated into either left-sided conventional DLT group ( n = 95) or left-sided ANKOR DLT group ( n = 95). The direction and depth of DLT position were compared via fiberoptic bronchoscopy (FOB) after endobronchial intubation between the groups. There was no significant difference in the number of right mainstem endobronchial intubations between the two groups ( p = 0.468). The difference between the initial depth of DLT placement and the target depth confirmed by FOB was significantly lower in the ANKOR DLT group than in the conventional DLT group (1.8 ± 1.8 vs. 12.9 ± 9.7 mm; p < 0.001). In conclusion, the ANKOR DLT facilitated its initial positioning at the optimal depth compared to the conventional DLT.

In this study, a donkey-specific primer pair and probe were designed from mitochondrial cytochrome b gene for the detection of raw donkey meat and different processed meat mixtures. The PCR product size for donkey DNA was 99 bp, and primer specificity was verified using 20 animal species. The limit of detection (LOD) was examined by serially diluting donkey DNA. Using real-time PCR, 0.001 ng of donkey DNA could be detected. In addition, binary meat mixtures with various percentages of donkey meat (0.001%, 0.01%, 0.1%, 1%, 10%, and 100%) in beef were analyzed to determine the sensitivity of this real-time PCR assay. At least 0.001% of donkey meat was detected in raw, boiled, roasted, dried, grinded, fried, and autoclaved meat mixtures. The developed real-time PCR method showed sufficient specificity and sensitivity in identification of donkey meat and could be a useful tool for the identification of donkey meat in processed products., Competing Interests: The authors declare no conflict of interest.

Fruit allergies have become more common in recent years, and are now a serious health problem. In this study, a multiplex PCR assay was used to detect potential fruit allergens causing food allergy labeling in Korea. For the detection of these allergens, specific primer pairs were designed to amplify the allergen-coding genes Cyclophilin (tomato), Mdtl 1 (apple), Pru p 2.01A (peach) and Pectin methylesterase inhibitor (kiwi), and primer pair targeting the 18S ribosomal RNA gene was additionally used as an endogenous control. Primer specificity was assessed with 23 plant species. A mixture of DNA from the four fruits was serially diluted and used to determine the sensitivity of the multiplex PCR assay, which was approximately 0.08 ng. Eleven commercial fruit products were evaluated to verify the applicability of the multiplex PCR assay. This assay is expected to be a specific and efficient method for detecting fruit allergens in foods., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© The Korean Society of Food Science and Technology 2019.)

Shrimp is seafood that can commonly trigger allergic reactions. In this study, the ultrafast real-time PCR assay with portable device was developed to detect a shrimp-derived major allergen, tropomyosin, without complicated DNA extraction. For shrimp allergen detection, a specific primer pair was designed based on the shrimp tropomyosin gene and 18S ribosomal RNA gene as internal control. Primer specificity was assessed using 8 common seafood species. Serially diluted shrimp DNA was used to determine the limit of detection of the ultrafast PCR system, which was approximately 3.2 pg. Twenty-three food samples containing shrimp were evaluated to verify the applicability of a direct ultrafast PCR method for detecting shrimp allergens without DNA isolation. It took less than 30 min from sample preparation-to-result analysis to detect shrimp DNA in raw and processed samples. Therefore, this PCR system can be effectively and conveniently utilized in the field to detect shrimp in various food products., Competing Interests: Compliance with ethical standardsThe authors declare no conflict of interest.

Stimuli with intrinsic emotional value, like emotional faces, and stimuli associated with reward and punishment are often prioritized in visual awareness relative to neutral stimuli. Recently, Anderson, Siegel, Bliss-Moreau, and Barrett (2011) demonstrated that simply associating a face with affective knowledge can also influence visual awareness. Using a binocular rivalry task (BR), where a face was shown to one eye and a house to the other, they found that faces paired with negative versus neutral and positive behaviors dominated visual awareness. We were interested in whether faces associated with negative information would also be capable of reaching awareness more quickly in the first place. To test this, we set out to replicate Anderson and colleagues' finding and to examine whether it would extend to breaking continuous flash suppression (b-CFS), a technique where a dynamic mask shown to one eye initially suppresses the stimulus shown to the other eye. Participants completed a learning task followed by BR and b-CFS tasks, in counterbalanced order. Across both tasks, faces associated with negative behaviors were treated no differently from faces associated with neutral or positive behaviors. However, faces associated with any type of behavior were prioritized in awareness over novel faces. These findings indicate that while familiarity influences conscious perception, the influence of affective person knowledge on visual awareness is more circumscribed than previously thought. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)

Tetragenococcus halophilus strain FBL3 is a lactic acid bacterium isolated from galchijeot, a fermented food made from the salted guts of the hairtail fish, in the Republic of Korea. The draft genome of T. halophilus strain FBL3 comprised 87 contigs (≥1 kb) with a total size of 2,420,904 bp and a G+C content of 38.5%., (Copyright © 2017 Kim et al.)

Administration of calcitonin (CT) or parathyroid hormone (PTH) in rats, induced phosphaturia with a concomitant increase in urinary excretion of cyclic AMP. CT produced a rise in arterial cAMP and filtered cAMP, with no increase in urinary nephrogenous cAMP. PTH on the other hand, produced an elevation in urinary nephrogenous cAMP with no increase in arterial cAMP and filtered cAMP. These results indicate that the source of urinary cAMP after CT is non-renal, whereas after PTH it is renal in origin.

Alcohol ingestion during pregnancy is known to cause fetal malformation and growth retardation. We investigated the effect of alcohol on mineral content and fetal development in rats fed 24% (v/v) alcohol eight weeks prior to and during pregnancy. Rats ingesting alcohol produced fewer fetuses (6.3 +/- 0.3 vs 9.6 +/- 0.3 in control) with lower fetal weight (3.48 +/- 0.09 vs 4.12 +/- 0.08 gm in control) and heavier placentas (0.66 +/- 0.05 vs 0.50 +/- 0.01 gm in control). The fetuses of alcoholic rats contained lower zinc (423.8 +/- 4.5 vs 459.9 +/- 5.4 microEq/100 gm dry weight in control) and magnesium (12.4 +/- 0.1 vs 12.7 +/- 0.1 mEq/100 gm dry weight in control) in the total carcass.

The response to parathyroid hormone (PTH) and calcitonin (CT) was studied in eight children with various bone diseases by determining the serum calcium (Ca) and phosphate (P) concentration, urinary phosphate excretion rate, renal phosphate clearance, the percentage of filtered phosphate reabsorbed by the renal tubule (%TRP), creatinine clearance (Ccr), urinary cyclic adenosine 3',5' monophosphate excretion rate (UcGMPV). Administration of PTH caused no significant change in serum Ca and P values, whereas CT produced a decrease in Ca (delta Ca, -1.4 +/- 0.1 mg/100 ml) and P (delta P; -1.1 +/- 0.1 mg/100 ml). There was an increase in UcAMP V (delta UcAMP; 437 +/- 74 nmoles/min/100 ml Ccr) without any significant change in UcGMPV after administration of PTH. Phosphaturia was produced by both PTH (delta TRP, -18 +/- 3%) and CT (delta TRP, -13 +/- 2%). However, CT did not elicit any increase in either UcAMPV or UcGMPV.

The effect of hypomagnesemia on renal concentrating ability was assessed in rats fed diets either low in magnesium or low in magnesium and calcium for 30 days. The rats fed a low-magnesium diet became hypomagnesemic (0.26 +/- 0.03 versus 1.53 +/- 0.04 mEq/L in controls), hypercalcemic (5.96 +/- 0.04 versus 5.22 +/- 0.11 mEq/L in controls), and hypokalemic (3.1 +/- 0.1 versus 4.2 +/- 0.4 mEq/L in controls) with decreased muscle content of potassium. Despite being hypomagnesemic, hypercalcemic, and potassium depleted, the rats had normal renal concentration ability (2499 +/- 65 versus 2415 +/- 119 mOsm/kg H2O in control). Those rats fed a diet low in both magnesium and calcium became hypomagnesemic (0.41 +/- 0.08 versus 1.53 +/- 0.04 mEq/L in controls) but were hypocalcemic. They also had normal renal concentrating ability (2399 +/- 109 versus 2415 +/- 119 mOsm/kg H2O in controls). It is concluded that hypomagnesemia does not decrease renal concentrating ability in rats. Furthermore, a normal concentrating ability demonstrated in hypomagnesemic rats, in spite of hypercalcemia and potassium depletion suggests that hypomagnesemia may ameliorate the deleterious effects of hypercalcemia and/or potassium depletion on renal concentrating ability.

Cyclic adenosine monophosphate (cAMP) is thought to be a second messenger for the actions of both parathyroid hormone (PTH) and calcitonin (CT). We examined the release of cAMP from rat bone in vivo after administration of synthetic rat PTH-(1-34) (rPTH), synthetic human PTH-(1-34) (hPTH), or synthetic human CT (hCT). Blood from the venous effluent of the femoral bone of rats (bone blood) was drawn at 5 and 10 minutes after the administration of hormones. The cAMP content of the bone blood was then compared to the cAMP content of arterial blood. In both kidney-clamped and non-kidney-clamped rats, hCT led to a significantly greater concentration of cAMP in the bone blood than in the arterial blood. We interpret this to be due to bone production and release of cAMP. Neither hPTH nor rPTH produced a significantly greater amount of cAMP in the bone blood than in arterial blood. These data do not preclude the possibility that there was a production of cAMP within the bone tissue itself after PTH but suggest that there was no release of cAMP from the bone into the bone blood.

Four cases of familial bone dysplasia with hyperphosphatasaemia were treated with synthetic human calcitonin. Prior to therapy, all four cases were characterized by marked bone deformity, pain, tenderness and elevated levels of serum alkaline phosphatase and urinary hydroxyproline. Treatment with calcitonin produced in each case a striking clinical, biochemical and radiographic remission. Pain and tenderness was greatly diminished and urinary hydroxyproline and serum alkaline phosphatase levels were significantly decreased. Radiographic regression of the bony abnormalities was apparent as early as 4 1/2 months after the start of treatment. Prior to therapy bones exhibit no real organization. After calcitonin treatment, the radiographic appearance of a normal cortex and medullary cavity was clearly evident for the first time.

Hypocalcemia is a frequent feature of hypomagnesemia in man and several other species. To elucidate the cause of this hypocalcemia, we have studied a child with primary hypomagnesemia and secondary hypocalcemia during magnesium supplementation when he was normomagnesemic and normocalcemic and after magnesium restriction for 16 days when he quickly became hypomagnesemic (0.5 meq/liter) and hypocalcemic (3.4 meq/liter) and had positive Chvostek's and Trousseau's signs. Whether in the normomagnesemic or hypomagnesemic state, intravenous bovine parathyroid extract (PTE) 8 U. S. P. U/kg promptly caused transient increases in the urinary phosphate excretion, renal phosphate clearance and cyclic AMP excretion. The magnitudes of these responses were similar in the two states, and similar to those observed in a hypoparathyroid patient. When the patient was hypomagnesemic and hypocalcemic, intramuscular PTE, 8 U/kg at 8-h intervals for four doses promptly caused hypercalcemia. The findings indicate that the end-organs were responsive to parathyroid hormone. The concentrations of serum parathyroid hormone (PTH) were normal in the normomagnesemic state ranging from 0.15 ng/ml to 0.40 ng/ml. Serum PTH did not increase in the hypomagnesemic state in spite of hypocalcemia. Indeed, PTH became unmeasurable in four consecutive samples at the end of the period of magnesium restriction. The concentrations of serum calcitonin remained unmeasurable (< 0.10 ng/ml) throughout the study, implying that excess calcitonin was not the cause of hypocalcemia in magnesium depletion. The findings in this study support our thesis that magnesium depletion causes impaired synthesis or secretion of parathyroid hormone. This impairment would account for the hypocalcemia observed in the hypomagnesemic state.

Hypocalcemia in the hypomagnesemic state in man is usually attributed to refractoriness of end-organs to the calcemic action of parathyroid hormone. We studied the responsiveness of end-organs to bovine parathyroid extract (PTE) in magnesium-depleted and control dogs by the following three methods after thyroparathyroidectomy: (a) assessment of the calcemic response to a set dose of PTE (0.3 U/kg per hr); (b) assessment of PTE dose required to attain normocalcemia; (c) evaluation of regression lines of plasma calcium concentration on PTE dose. The calcemic response of magnesium-depleted thyroparathyroidectomized puppies to a set dose of PTE was similar to that of control puppies. There was no significant difference in the dose of PTE required to attain normocalcemia nor in the dose-response relations between the plasma calcium concentration and the PTE dose. In a group of magnesium-depleted puppies with intact thyroid and parathyroid glands, the dose of PTE required to attain normocalcemia was similar to that required in thyroparathyroidectomized animals, indicating calcitonin was not a factor contributing to hypocalcemia. We conclude that hypocalcemia in magnesium-depleted puppies is not due to refractoriness of end-organs to the calcium-mobilizing action of parathyroid hormone. Defective synthesis or diminished secretion of parathyroid hormone is suggested as an explanation.