[Allogeneic hematopoietic stem cell transplantation in acute leukemia patients with the SET-NUP214 fusion gene: Efficacy and survival analysis]

Objective: To investigate the clinical efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with acute leukemia who are positive for the SET-NUP214 fusion gene (SET-NUP214⁺AL). Methods: This was a retrospective case series study. Clinical data of 18 patients with SET-NUP214⁺AL who received allo-HSCT in the First Affiliated Hospital of Soochow University and Soochow Hongci Hematology Hospital from December 2014 to October 2021 were retrospectively analyzed to investigate treatment efficacy and prognosis. The Kaplan-Meier method was used for survival analysis. Results: Of the 18 patients, 12 were male and 6 were female, and the median age was 29 years (range, 13-55 years). There were six cases of mixed phenotype acute leukemia (three cases of myeloid/T, two cases of B/T, one case of myeloid/B/T), nine cases of acute lymphoblastic leukemia (ALL) (one case of B-ALL and eight cases of T-ALL), and three cases of acute myeloid leukemia. All patients received induction chemotherapy after diagnosis, and 17 patients achieved complete remission (CR) after chemotherapy. All patients subsequently received allo-HSCT. Pre-transplantation status: 15 patients were in the first CR, 1 patient was in the second CR, 1 was in partial remission, and 1 patient did not reach CR. All patients were successfully implanted with stem cells. The median time of granulocyte and platelet reconstitution was +12 and +13 days, respectively. With a median follow-up of 23 (4-80) months, 15 patients survived, while 3 patients died. The cause of death was recurrence of SET-NUP214⁺AL after transplantation. After allo-HSCT, 5 patients relapsed. The estimated 3-year overall survival (OS) and relapse-free survival (RFS) rates were 83.3%±15.2% and 55.4%±20.7%, respectively. Among the 15 patients who achieved CR before transplantation, there was no significant difference in OS and RFS between haploidentical HSCT and matched sibling donor HSCT (all P>0.05). Conclusions: Allo-HSCT can improve the prognosis and long-term survival rate of patients with SET-NUP214⁺AL. Disease recurrence is the most important factor affecting long-term survival.

Effect of Plasticization on Stretching Stability of Poly(Vinyl Alcohol) Films: A Case Study Using Glycerol and Water

Adding small molecular plasticizers is the most common route to tailor the stretchability of poly(vinyl alcohol) (PVA). However, how the plasticization along with the nature of the plasticizer governs the structural homogeneity during stretching remains an open question to answer. Herein, two representative plasticizers, glycerol (GLY) and water, are chosen to endow the PVA films with ductility. It is found that large strain cavitations cause obvious stress whitening in the PVA/H₂ O films; on the contrary, most of the PVA/GLY films maintain transparent undergoing tensile deformation. Through a combination of experimental inspections and molecular dynamic simulation, it is revealed that partial water molecules that behave as free water will aggregate into microdomains, which serve as mechanical defects responsible for yielding voids. Whereas, the GLY plasticizer homogeneously disperses at a molecular level and interacts with PVA chains through strong hydrogen bonds. More interestingly, it is illustrated that the dispersion and bound states of plasticizers are closely related to the mechanical character of the plasticized PVA films. These findings offer new insight into the working mechanism of plasticization on the structural stability during stretching, and guide the design of PVA/plasticizer system to obtain excellent comprehensive mechanics.

[Preliminary exploration of the metabolic profile and metabolic pathways in newly diagnosed multiple myeloma]

Objective: To explore the metabolite profile and metabolic pathways of newly diagnosed multiple myeloma (MM). Methods: Gas chromatography-mass spectrometry (GC-MS) was employed for the high-throughput detection and identification of serum samples from 55 patients with MM and 37 healthy controls matched for age and sex from 2016 to 2017 collected at the First Affiliated Hospital of Soochow University. The relative standard deviation (RSD) of quality control (QC) samples was employed to validate the reproducibility of GC-MS approach. The differential metabolites between patients with MM and healthy controls were detected by partial least squares discrimination analysis (PLS-DA), and t-test with false discovery rate (FDR) correction. Metabolomics pathway analysis (MetPA) was employed to construct metabolic pathways. Results: There were 55 MM patients, including 34 males and 21 females. The median age was 60 years old (42-73 years old). There were 30 cases of IgG type, 9 cases of IgA type, 1 case of IgM type, 2 cases of non-secreted type, 1 case of double clone type and 12 cases of light chain type, including 3 cases of kappa light chain type and 9 cases of lambda light chain type. The result of QC sample test showed that the proportion of compounds with the RSD of the relative content of metabolites < 15% was 70.21% obtained by the reproducibility of GC-MS experimental data, which implied that the experimental data were reliable. A total of 17 metabolites were screened differently with the healthy control group, including myristic acid, hydroxyproline, cysteine, palmitic acid, L-leucine, stearic acid, methionine, phenylalanine, glycerin, serine, isoleucine, tyrosine, valine, citric acid, inositol, threonine, and oxalic acid (VIP>1, P<0.05). Metabolic pathway analysis suggested that metabolic disorders in MM patients comprised mainly phenylalanine metabolism, glyoxylic acid and dicarboxylic acid metabolism, phosphoinositide metabolism, cysteine and methionine metabolism, glycerolipid metabolism, glycine, serine, and threonine metabolism. Conclusion: Compared with normal people, patients with newly diagnosed MM have obvious differences in metabolic profiles and metabolic pathways.

Diagnosis and genetic analysis of a case with glycogen storage disease type V caused by compound heterozygous mutations in the PYGM gene

Glycogen storage disease type V is an autosomal recessive genetic disorder caused by muscle glycogen phosphorylase (PYGM) deficiency, which is characterized by exercise intolerance, second wind phenomena and high level of serum creatine kinase. In this study, we reported a Chinese young man with glycogen storage disease type V, with lower extremity weakness after exercise, increased creatine kinase, and slight fat infiltration in the posterior group of thigh muscle by magnetic resonance imaging (MRI). The proband had complex heterozygous PYGM disease-causing mutations, including c.308T>C (p.L103P) variant transmitted from the mother and c.260_261delCT (p.S87Ffs*23) from the father, of which the former was a novel PYGM mutation. This study enriched the PYGM pathogenic gene mutation spectrum, contributed to improve clinicians' understanding of glycogen storage disease type V and provided a reference for further genetic study of the disease.

Pursuing Phase Transitions of a Concentrated Polymer Solution by In Situ Fluorescence Measurements Based On Aggregation-Induced Emission

Concentration-dependent phase transitions in concentrated solutions have remained speculation due to the serious impediment of macromolecule dynamics by intensive topological entanglement or intermolecular interaction as well as the absence of powerful tool for detecting changes in chain or segment movement. Herein, taking a general polymer, namely, poly(vinyl alcohol) (PVA), as an example, a water-soluble fluorescent molecule with aggregation-induced emission (AIE) is introduced into the PVA solutions as a chain dynamics indicator to investigate phase transitions at high concentrations through in situ monitoring of the solvent evaporation process. Two turning points of fluorescent intensity are observed for the first time at mean concentrations of ∼25% and ∼45%, corresponding to the gelation and amorphous-to-crystalline transitions, respectively. Our work offers a fundamental insight into the physical nature of concentrate-dependent nonequilibrium transitions and develops a reliable and sensitive approach based on the AIE phenomenon for following high-concentration-triggered property changes of a polymer solution.

A study of congenital generalized lipodystrophy (CGL) caused by BSCL2 gene mutation

Congenital generalized lipodystrophy (CGL) is an extremely rare genetic disease mainly characterized by absence of whole-body adipose tissue and metabolic dysfunctions such as insulin resistance, diabetes mellitus, hypertriglyceridemia, hepatic steatosis, and acanthosis nigricans. In this study, we reported a novel case of a young woman patient with CGL. The patient came to the hospital for early-onset lipodystrophy and diabetes. She was 19-year-old with a height of 160 cm, a weight of 46 kg, BMI of 17.9 kg/m², and a serum leptin level of 0.14 μg/L. Genomic DNA was extracted from blood samples of the patient and her family members, including her mother, father and brother. Genetic analysis revealed compound heterozygous mutations of the BSCL2 gene (c.560A>G and c.565G>T) in the patient. Her father carried a heterozygous mutation (c.565G>T), and her mother carried a heterozygous mutation (c.560A>G) in the BSCL2 gene. The mutant p.Y187C plasmid was transfected into HEK293T cells. The protein expression of SEIPIN and its interaction with glycerol-3-phosphate acyltransferase (GPAT3) were observed to be reduced. In addition, based on primary cultured skin fibroblasts from the patient, SEIPIN protein was decreased, and lipid droplets were much smaller when fatty acid was stimulated compared with those observed from healthy subject controls. However, histone deacetylase inhibitors (HDACis) was found capable of rescuing SEIPIN protein in fibroblasts of the patient. In addition, we further summarized and discussed gene mutations of BSCL2 reported in the current literature. Collectively, these findings have expanded the clinical phenotype and pathogenic gene spectrum of CGL, which might help clinicians to achieve better management of lipodystrophy.

Establishment and operation of glucose clamp technique in mice

Glucose metabolism plays a central role in energy supply and metabolism regulation in various tissues and organs. Besides, insulin is the sole hormone lowering blood glucose in the body, and islet function and insulin sensitivity are the key steps modulating glucose metabolism. Since the development of glucose clamp technology, it has been recognized as the gold standard for evaluating insulin metabolism. The main categories include hyperinsulinemia-euglycemia clamp, hyperglycemia clamp, and hyperinsulinemia-hypoglycemia clamp. These can be done on either anesthetized mice or conscious and unrestricted mice. This protocol focuses on the establishment and operation of the mouse glucose clamp technique, including preparation of instrument consumables, surgical operations, clamping procedures, and precautions, serving as reference and guidance.

p38MAPK silencing attenuates scar proliferation after cleft palate repair surgery in rats via MRTF-A/SRF pathway

Scarring is the primary factor of maxilla growth restriction among people who have undergone cleft palate repair surgery. p38 mitogen-activated protein kinase (p38MAPK) promotes fibrosis in a variety of organs. However, its role in post-surgery scarring on the hard palate has not been fully understood. This study is designed to investigate the role of p38MAPK in scar formation and maxilla growth of rats. We removed the mucosa on the hard palate of rats and applied the p38MAPK silencing adenovirus vector on it two weeks after surgery. Then the scarring tissue and maxilla growth were evaluated by histological and morphological examination. The effect of p38MAPK silencing on scarring-related genes in fibroblasts was also studied. We found that local injection of Ad-p38MAPK-1 in vivo effectively reduces the expression of p38MAPK and scarring-related proteins and weakens the impact of scarring on the width of the hard palate. Mechanistically, p38MAPK silencing inhibits the expression of α-smooth muscle actin (α-SMA) via mediating the production and nuclear localization of myocardin-related transcription factor A (MRTF-A) in fibroblasts. These results reveal a molecular pathway of scar formation involving p38MAPK/MRTF-A stimulation and support targeting p38MAPK as a potentially effective treatment for post-surgery scarring on the hard palate.

Hydrogen-bond-dominated mechanical stretchability in PVA films: from phenomenological to numerical insights

Hydrogen bonds (H-bonds) in poly(vinyl alcohol) (PVA) play a crucial role in macroscopic mechanical properties, particularly for stretchability. However, there is still some ambiguity about the quantitative dependence of H-bond interactions on the mechanical performance, mainly attributed to the difficulty in the discrimination of various H-bond types. Herein, small molecular chemicals as plasticizers were incorporated into the PVA matrix to tailor the H-bonding interactions. By altering the PVA molecular weight, plasticizer type and loading, both the stretchability and H-bond content were regulated on a large scale. By a combination of DMA, IR spectroscopy, MD simulation and solid-state ¹³C-NMR, every sort of H-bond in PVA was assigned, and their relative fractions were ascertained quantitatively. After correlating the elongation ratio with the relative fraction of the different types of H-bonding interaction, it was found that all the pairs of elongation vs. intermolecular H-bond content derived from different series of PVA/plasticizer films could be plotted into a master curve and exhibited good linearity, indicating that intermolecular H-bonds dominate the mechanical stretchability in PVA films. Our efforts contribute towards an in-depth understanding of performance optimization induced by H-bond manipulation from empirical, phenomenological aspects to intrinsic, numerical insights.

Treatment of oral lichen planus by surgical excision and acellular dermal matrix grafting: Eleven case reports and review of literature

BACKGROUND

Oral lichen planus (OLP) is a chronic inflammatory disorder, and it can affect normal oral function. The conventional treatments for OLP are not always effective, and relapse easily occurs. Therefore, treatment of OLP is difficult and challenging. In this study, we evaluated over a long period the clinical efficacy of surgical excision and acellular dermal matrix (ADM) grafting in patients with refractory OLP.

CASE SUMMARY

Eleven patients with refractory OLP underwent a standardized protocol of surgical excision and ADM grafting. The condition of the area of the grafted wound, the intraoperative maximum mouth opening, pain, and clinical healing were assessed at postoperative follow-up visits. All patients had a flat surgical area with similar mucosal tissue coverage and local scar formation. Patients had no irritation and pain in their mucous membranes when eating acidic and spicy food. All patients’ mouth openings returned to normal within 2-6 mo after surgery. During follow-up, none of the patients had recurrence of OLP after surgery. The longest follow-up was 11 yr and the shortest was 6 mo, and none of the patients relapsed during follow-up.

CONCLUSION

Surgical excision and ADM grafting could be an effective method to treat refractory OLP.

Negative pressure drainage-assisted irrigation for maxillofacial space infection

OBJECTIVE

In this study, the clinical effect of negative pressure drainage-assisted irrigation (NPDI) technique was evaluated in treating maxillofacial space infection (MSI) by comparing with traditional technique.

METHOD

A prospective study was conducted in 58 patients with MSI. The patients were randomly divided into two groups based on different treatment techniques. Thirty patients receiving NPDI were included in NPDI group, and 28 patients receiving traditional technique were included in traditional group. Case data (gender, age, etiology, concurrent illness, diabetes, involved spaces, preoperative white cell count, airway control method) and clinical effect (postoperative hospital stay, total cost of admission) for the two groups were analyzed.

RESULTS

Patients in both groups were cured clinically. There were no significant differences in gender, age, etiology, concurrent illness, diabetes, involved spaces, preoperative white cell count, and airway control method in NPDI group and traditional group (p > .05). The postoperative hospital stay and the total cost of admission in the NPDI group were significantly lower than the traditional group (p < .001).

CONCLUSION

Negative pressure drainage-assisted irrigation used in the treatment of MSI can shorten the postoperative hospital stay, reduce the total cost of admission, and show favorably clinical effect. It is a clinically recommended method for MSI.

[A study on the status and problem countermeasures of key occupational disease monitoring in Shandong, China, from 2015 to 2017]

Objective: To analyze the completion status, monitoring results, and existing problems of key occupational disease monitoring in Shandong, China, from 2015 to 2017, and to provide reference materials for improving monitoring quality and carrying out occupational disease prevention and control. Methods: The monitoring situation including project coverage, data collection, monitoring results, and monitoring quality of key occupational diseases in Shandong from 2015 to 2017 were described and comparatively analyzed. Results: In the past three years, the uncoverage rate of monitored counties (38.69% in 2015, 10.95% in 2016, and 5.11% in 2017) , the non-work rate of occupational health examination institutions (41.67% in 2015, 18.02% in 2016, and 8.72% in 2017) , and the non-work rate of occupational disease diagnosis institutions (42.31% in 2015, 38.46% in 2016, and 38.46% in 2017) in Shandong decreased year by year. The number of institutions with key occupational hazard factors reported to the safety supervision and management department increased year by year (it was 24140 in 2017, with an increase of 40.50% compared with 2016 and an increase of 114.62% compared with 2015) ; the key occupational hazard factors in enterprises were mainly noise (72.76%) , followed by benzene, silica dust, and coal dust. The number of workers exposed to key occupational hazard factors reported to the safety supervision and management department increased year by year; in 2017, it was 729245, with an increase of 39.78% compared with 2016 and an increase of 84.81% compared with 2015. The ratio of people exposed to key occupational hazard factors identified by the medical examination to the total people in the safety supervision system in a year decreased year by year (40.87% in 2015, 23.86% in 2016, and 17.95% in 2017) . Conclusion: In Shandong, the supervision of enterprises with key occupational hazard factors and the responsibility of enterprise protection should be strengthened. The occupational health examination rate of workers should be improved. It is suggested that we should carry out the special investigations and occupational health risk assessment for key enterprises and key populations.

[A prospective multi-center trial of non-interventional and observational study of lenalidomide in Chinese patients with multiple myeloma]

Objective: To evaluate the efficacy and safety of lenalidomide in a real-world clinical practice in Chinese patients with multiple myeloma (MM). Methods: It was a prospective, multi-center, observational study. A total of 165 consecutive patients with MM treated with lenalidomide-based regimens were enrolled in 12 hospitals from June 2013 to November 2015. Relevant information was recorded, such as baseline clinical data, cytogenetic abnormalities, treatment regimens, and duration of treatment, safety, and survival. Results: (1)There were 126 relapsed and refractory MM (RRMM) patients, 25 newly diagnosed patients and 19 maintenance patients. The evaluable RRMM patients accounted for 120 cases, among which 74 cases(61.7%) reached the partial response (PR) or above, and a very good partial response (VGPR) in 16 patients (13.3%), a complete response (CR) in 14 cases (11.7%), a strictly complete response (sCR) in 4 cases (3.3%). Thus, a VGPR or above in 34 patients accounted for 28.3%. (2)The median follow-up was 13 months, the median time to progression 12 months. The median survival after receiving lenalidomide was 19 months, and the median overall survival (OS) was 62 months. (3) The univariate analysis in 120 RRMM patients suggested that prognostic factors for significant improvement in PFS included normal karyotype, international staging system (ISS) Ⅰ-Ⅱ, t(4; 14) negative (detected by fluorescence in situ hybridization), non-bortezomib resistance and response to previous regimens. As to OS, non-bortezomib resistance, response to previous regimens and non-primary refractoriness were positive factors. Multivariate analysis showed that the response to previous regimens (PR or better) was an independent good prognostic factor for progress-free survival(PFS), non-bortezomib resistance and non-primary refractoriness for OS. (4) Grade 3 or 4 adverse events that occurred in more than 10% of all enrolled patients were neutropenia (12.7%), leukocytosis(11.5%) and thrombocytopenia (12.7%). Owing to intolerance of toxic side effects, 7 cases withdrew lenalidomide. Conclusions: No matter what combination, regimens containing lenalidomide are effective to RRMM patients with overall response rate 61.7%, a time to progression 12 months and an overall survival 62 months.The toxicity is quite tolerable and manageable. In addition, the response to previous treatment (reached PR or above) is the independent good prognostic factor for PFS, non-bortezomib resistance and non-primary refractoriness for OS. Clinical trail registration: Clinicaltrials.gov, NCT01947309.

Correlation of cadherin-17 protein expression with clinicopathological features and prognosis of patients with sporadic gastric cancer

This study aimed to explore the correlations between cadherin-17 (CDH17) protein expression and the clinicopathological features and prognosis of patients with sporadic gastric cancer (GC). Nine relevant studies of 1,960 patients were identified using electronic database searches supplemented with a manual search in strict accordance with inclusion and exclusion criteria. Statistical analyses were conducted using STATA 12.0 statistical software. Relative risks and 95% confidence intervals were determined, and Z test was used to measure the significance of the overall effect size. A total of nine eligible cohort studies were included in this meta-analysis. The expression of CDH17 in patients with diffuse GC was significantly higher than in those with intestinal-type GC. Moreover, the tumor depth of invasion differed significantly between patients with positive CDH17 (CDH17+) and negative CDH17 (CDH17-) GC. However, there were no significant differences between CDH17+ and CDH17- GC patients with respect to tumor node metastasis clinical stages, histological grades, or lymph node metastasis. Despite the differences in invasive depth, there was no significant difference in 5-year survival rates between CDH17+ and CDH17- GC patients. Our meta-analysis provides evidence that CDH17 protein expression may be associated with the development of GC, suggesting that CDH17 is an important biomarker that could be useful for the early diagnosis of GC. However, CDH17 levels do not appear to impact overall survival.

EMP1 inhibits nasopharyngeal cancer cell growth and metastasis through induction apoptosis and angiogenesis

This study aimed to analyze the expression, clinical significance of epithelial membrane protein-1 (EMP1) in nasopharyngeal carcinoma, and the biological effect in its cell line by EMP1 overexpression. Immunohistochemistry and Western blot were used to analyze the EMP1 protein expression in 75 cases of nasopharyngeal cancer and 31 cases of normal tissues to study the relationship between EMP1 expression and clinical factors. Recombinant lentiviral vector was constructed to overexpress EMP1 and then infect nasopharyngeal cancer CNE2 cell line. Quantitative real-time RT-PCR and Western blot were used to detect the mRNA level and protein of EMP1. MTT assay, cell apoptosis, migration, and invasion assays were also conducted to determine the influence of the upregulated expression of EMP1 that might be found on CNE2 cells' biological effect. Immunohistochemistry and Western blot: The level of EMP1 protein expression was found to be significantly lower in nasopharyngeal cancer tissue than in the normal tissues (P < 0.05). Decreased expression of EMP1 was significantly correlated with T stages, lymph node metastasis, clinic stage, and histological grade of patients with nasopharyngeal cancer (P < 0.05). Meanwhile, the loss of EMP1 expression correlated significantly with poor overall survival time by Kaplan-Meier analysis (P < 0.05). The result of biological function has shown that CNE2 cell-transfected EMP1 had a lower survival fraction, higher cell apoptosis, significant decrease in migration and invasion, higher caspase-9, and lower vascular endothelial growth factor C protein expression compared with CNE2 cell-untransfected EMP1 (P < 0.05). EMP1 expression decreased in nasopharyngeal cancer and correlated significantly T stages, lymph node metastasis, clinic stage, histological grade, and poor overall survival, suggesting that EMP1 may play important roles as a negative regulator to nasopharyngeal cancer cell.

[Influence of transplantation and some clinical factors on prognosis of patients with diffuse large B-cell lymphoma]

This study was aimed to analyze the survival status of patients with diffuse large B-cell lymphoma (DLBCL) and to investigate the influence of autologous hematopoietic stem cell transplantation (auto-HSCT), different pathological types, International Prognosis Idex (IPI) on prognosis. One hundred and sixteen cases of DLBCL were analyzed retrospectively. The treatment efficacy of R-CHOP alone and R-CHOP combined with auto-HSCT as well as the influence of different immunopathologic types, IPI, hypersensitive C-reactive protein (HSCRP), α-hydroxybutyric acid deaminase (HBDH) on the prognosis of DLBCL patients including overall survival (OS) rate, progression-free survival (PFS) rate were analyzed. The results indicated that the 5-year OS for all patients was 72.4%. in which 30 patients with Ann Arbor staging III-IV received auto-HSCT plus R-CHOP. The prognosis of the 30 patients was better than that of 86 cases received R-CHOP chemotherapy alone (5-year OS was 82.5% vs 69.0%, 5-year PFS was 77.1% vs 68.3%) (P < 0.05). The prognosis of patients in germinal center B-cell-like group (GCB group) was better than that of patients in activated B-cell-like group (ABC group). Some clinical features were associated with poor prognosis including OS and PFS, such as age, B symptoms, IPI scores, the level of LDH, HSCRP and HBDH (P < 0.05) in which the level of LDH, age ≥ 60 years and B symptoms were independent prognostic factors in DLBCL patients (P < 0.05). It is concluded that auto-HSCT combined with R-CHOP can improve the long-term survival of DLBCL patients. The prognosis of patients in GCB group is better than that of patients in the ABC group. The clinical features such as age, B symptoms, IPI scores and LDH are associated with prognosis.

Thromboxane/prostacyclin balance in type II diabetes: gliclazide effects

We studied serum thromboxane (TXB2), the prostacyclin metabolite, 6-keto-PGF1 (6KPGF1) glucose, insulin, and lipid/lipoprotein profiles in 27 patients with non-insulin-dependent diabetes mellitus (NIDDM) who were switched from therapy with glibenclamide (GLB) (with [GLBH] or without phenformin) to gliclazide for 3 months. We found that therapy with gliclazide was followed by a decrease in serum TXB2 (281.8 +/- 128.3 to 149.1 +/- 77.0 mg/L, P less than .001) and an increase in serum 6KPGF1 (60.5 +/- 19.1 to 96.0 +/- 40.3 mg/L, P less than .001). This was accompanied by a decrease in total and low-density lipoprotein (LDL) cholesterol and an increase in high-density lipoprotein (HDL) cholesterol, within the HDL3 cholesterol fraction. These changes were seen despite the fact that neither fasting plasma glucose nor insulin changed with therapy. These findings suggest that gliclazide may have beneficial actions on cardiovascular risk factors in these NIDDM patients.

Familial hyperinsulinemia associated with secretion of an abnormal insulin, and coexistence of insulin resistance in the propositus

A 45-yr-old muscular nonobese white man who had a 9-yr history of syncopal episodes was studied on several occasions between April 1979 and August 1984. Fasting glucose concentrations ranged between 74-115 mg/dl, and those of insulin ranged between 14-64 microU/ml. Reactive hypoglycemia 3-4 h after ingestion of glucose occurred in the first 2 yr. Glucose tolerance was impaired in 1979, from February 1982 through September 1983, and again in August 1984. The maximum plasma insulin response to glucose ranged between 475-1630 microU/ml. When studied in November 1982, insulin (0.1 U/kg) caused a fall in blood glucose concentration of only 25% (normal, greater than 50%), and maximal glucose utilization during the euglycemic hyperinsulinemic clamp was 7.5 mg/kg . min (normal, greater than 12 mg/kg . min). Plasma counterregulatory hormone concentrations were normal, and antibodies to insulin and the insulin receptor were absent. Binding of exogenous insulin to the patient's cellular receptors (monocytes, red blood cells, and skin fibroblasts) was normal. Insulin was purified from plasma by immunoaffinity and molecular sieve chromatography and was found to elute later than human insulin on reversed phase high performance liquid chromatography. It was more hydrophobic than normal human insulin and had only 10% of the activity of normal insulin in terms of ability to bind to and stimulate glucose metabolism in isolated rat adipocytes. The abnormal insulin was identified in two of three sons and a sister, but not in the mother, brother, or niece. Sensitivity to insulin was normal in the two sons who had abnormal insulin. These results suggest that in this family the abnormal insulin was due to a biosynthetic defect, inherited as an autosomal dominant trait. The hyperinsulinemia was not associated with diabetes in family members who had no insulin resistance.

Characterization of circulating insulin in insulin autoimmune syndrome

We examined the forms of circulating insulin in three patients with the insulin autoimmune syndrome by a method combining gel filtration and reverse phase high performance liquid chromatography (RP-HPLC). Insulin bound to circulating antibody was dissociated by molecular sieve chromatography at acid pH. The free insulin peak eluted from a Sephadex G-50 column was subsequently chromatographed on a Bio-Gel P-30 column. In all three patients, insulin coeluted with normal human insulin. However, when the partially purified insulins, obtained by gel filtration, were applied to RP-HPLC, an abnormally migrating insulin was found in two of three patients. The insulins were more hydrophobic than normal human, porcine, or bovine insulin, but were different from each other. A third patient had only a single insulin peak on RP-HPLC which corresponded to normal insulin. In contrast, the insulin from insulin-treated diabetic patients with antibodies to exogenous insulin corresponded to either porcine or bovine and normal human insulin. The antibodies in the circulation of these patients with the autoimmune syndrome were of the immunoglobulin G type and contained kappa and lambda-chains in the same proportions as antibodies in insulin-treated patients. Autoantibodies could not be distinguished from those secondary to exogenous insulin treatment on the basis of displacement of binding by human, beef, or pork insulin. These results suggest that in certain patients with the insulin autoimmune syndrome, there may be a molecular abnormality of circulating insulin. Whether this comprises a cause for the syndrome or is a result of posttranslational processing of insulin remains to be determined.

Identification of insulin variants in patients with hyperinsulinemia by reversed-phase, high-performance liquid chromatography

We have characterized the molecular forms of circulating insulins in patients with hyperinsulinemia of diverse etiology. We have also compared the efficacy of various chromatographic conditions using reversed-phase (RP) HPLC. Using 0.2% trifluoroacetic acid (TFA) and triethylamine (TEA) with acetonitrile as the organic modifier, at an elution rate of 0.17%/min, porcine, bovine, and human insulins could be easily separated as well as abnormal insulins in the plasma of a patient (J.R.) with hyperinsulinemia of unknown etiology. When the reversed-phase C18 column was changed and a gradient of 0.33%/min was used, the abnormal insulin in patient J.R. could not be separated. By changing the solvent system to acetonitrile and isopropanol (vol:vol, 3:1) containing 0.1% TFA, omitting the TEA, and using a gentle gradient of 0.1%/min, various semisynthetic analogues of human insulin could be easily separated and the abnormal insulin could be identified in the plasma of the patient J.R. Abnormal insulin was also found in a patient with MEN-I, but in contrast, the insulins in eight patients with benign sporadic insulinomas appeared to be normal. These results suggest that certain hyperinsulinemic states may be associated with an abnormal insulin and that RP-HPLC is useful for identification of insulin variants in the circulation. However, the conditions of RP-HPLC may be critical if the abnormalities of the insulin are subtle.