Production of alkaline protease by Aspergillus niger in a new combinational paper waste culture medium

Enzymes derived from microbial sources have gained increasing popularity in industrial applications over the past decades. Despite the high production cost, alkaline proteases have wide applications in industries such as tanneries, food production, and detergents. In recent years, there has been a shift towards utilizing natural carbon sources for cultivating microorganisms and extracting proteases in order to reduce production costs. This study aimed to investigate the biochemical and kinetic properties of protease enzymes obtained from Aspergillus niger cultivated in a paper waste medium and compare with the enzyme produced in a basal medium. Glucose is a more favorable carbon source compared to cellulose, so paper waste was pretreated with cellulose-degrading bacteria to convert cellulose into smaller carbohydrates. After the growth of A. niger in basal and combinational media, the enzymatic properties were compared between the extracted enzymes by using casein as substrate. The results demonstrated that A. niger could produce protease enzymes in the paper waste medium similar to the basal medium with more than 5-fold cost saving. The specific activity of the enzymes isolated from the basal and paper waste media was calculated to be 184.95 ± 10.56 U ml-1 and 169.88 ± 11.05 U ml-1, respectively. Carbon sources did not affect the optimum pH and temperature of the protease enzyme, which were found to be 8 and 37 °C, respectively. This study provides valuable insights into the production of alkaline protease from A. niger using a combinational medium (paper waste pretreated by cellulose-degrading bacteria), offering a cost-effective approach for industrial applications.

Motivations and personality characteristics of candidate sperm and oocyte donors according to parenthood status: a national study from the french CECOS network

STUDY QUESTION

In a non-commercial national gamete donation programme, do the motivations and personality characteristics of candidate sperm and oocyte donors differ according to their parenthood status?

SUMMARY ANSWER

Moderate differences exist between non-parent and parent candidate donors in motivations for gamete donation and representations as well as in personality characteristics.

WHAT IS KNOWN ALREADY

Several studies have analysed the motivations and experiences of oocyte or sperm donors, but mainly in countries where gamete donation is a commercial transaction, and very few studies have reported results of personality traits using personality inventory tests. No study has specifically investigated the motivations and personality characteristics of candidate gamete donors according to parenthood status.

STUDY DESIGN, SIZE, DURATION

A prospective study was carried out including 1021 candidate donors from 21 centres (in university hospitals) of the national sperm and egg banking network in France between November 2016 and December 2018.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In total, 1021 candidate gamete donors were included in the study. During their first visit, male (n = 488) and female candidate donors (n = 533) completed a questionnaire on sociodemographic characteristics, their motivations for donation and their representations of donation, infertility and family. Secondly, a NEO Personality Inventory (NEO-PI-R) exploring the Big Five personality traits was completed online. Results were compared between parent and non-parent candidate donors.

MAIN RESULTS AND THE ROLE OF CHANCE

Altruistic values were the principal motive for donation irrespective of parenthood status. Reassurance about their fertility or preservation of sperm for future use was more often reported in non-parent than in parent candidate donors. With regard to representation of gamete donation or of the family, independently of their parenthood status, candidate donors more frequently selected social rather than biological representations. Mean personality characteristics were in the normal range. Non-parent candidate donors had higher scores on openness and depression than parents, while parent candidate donors appeared more social than non-parents.

LIMITATIONS, REASONS FOR CAUTION

The personality characteristics inventory was not completed by all candidate donors included in the study. However, family status did not differ between the two groups (NEO-PI-R completed (n = 525) or not), while the group who completed the NEO-PI-R had a higher educational level. This national study was performed in a country where gamete donation is subject to strict legislation.

WIDER IMPLICATIONS OF THE FINDINGS

In a global context where reproductive medicine is commercialized and gamete donor resources are limited, this study found that altruism and social representations of gamete donation and family are the main motivations for gamete donation in a country which prohibits financial incentive. These findings are relevant for health policy and for gamete donation information campaigns.

STUDY FUNDING/COMPETING INTEREST(S)

Grant from the Agence de la Biomédecine, France. The authors have nothing to disclose related to this study.

TRIAL REGISTRATION NUMBER

N/A.

Final results for the neutron -asymmetry parameter A0 from the UCNA experiment

The UCNA experiment was designed to measure the neutron β-asymmetry parameter A0 using polarized ultracold neutrons (UCN). UCN produced via downscattering in solid deuterium were polarized via transport through a 7 T magnetic field, and then directed to a 1 T solenoidal electron spectrometer, where the decay electrons were detected in electron detector packages located on the two ends of the spectrometer. A value for A0 was then extracted from the asymmetry in the numbers of counts in the two detector packages. We summarize all of the results from the UCNA experiment, obtained during run periods in 2007, 2008–2009, 2010, and 2011–2013, which ultimately culminated in a 0.67% precision result for A0.

The neutron electric dipole moment experiment at the Spallation Neutron Source

Novel experimental techniques are required to make the next big leap in neutron electric dipole moment experimental sensitivity, both in terms of statistics and systematic error control. The nEDM experiment at the Spallation Neutron Source (nEDM@SNS) will implement the scheme of Golub & Lamoreaux [Phys. Rep., 237, 1 (1994)]. The unique properties of combining polarized ultracold neutrons, polarized 3He, and superfluid 4He will be exploited to provide a sensitivity to ∼ 10−28 e · cm. Our cryogenic apparatus will deploy two small (3 L) measurement cells with a high density of ultracold neutrons produced and spin analyzed in situ. The electric field strength, precession time, magnetic shielding, and detected UCN number will all be enhanced compared to previous room temperature Ramsey measurements. Our 3He co-magnetometer offers unique control of systematic effects, in particular the Bloch-Siegert induced false EDM. Furthermore, there will be two distinct measurement modes: free precession and dressed spin. This will provide an important self-check of our results. Following five years of “critical component demonstration,” our collaboration transitioned to a “large scale integration” phase in 2018. An overview of our measurement techniques, experimental design, and brief updates are described in these proceedings.

Investigation continuous noise exposure and occupational performance of the workers in the pharmaceutical industry: A Case Study in an Ampoule and Vial Production Industry

Introduction: Exposure to noise is considered as one of the most important health problems in various industries, especially pharmaceutical industry, which can ultimately lead to significant negative effects on labor force and occupational performance. The aim of this study was to investigate the relationship between continuous noise exposure and occupational performance of the workers in the pharmaceutical industry and ampoule production line in Iran. Method: This cross-sectional study was conducted through a descriptive-analytical method in 2015. The subjects were 100 workers exposed to noise in an ampoule and vial manufacturing factory in Iran. The sound measurement was carried out in accordance with ISO 9612: 2009. The Hersey and Goldsmith questionnaire (ACHIEVE model) was used to investigate the workers’ occupational performance, and the seven dimensions of the questionnaire as well as the final score of occupational performance was determined for each individual. Results: The results showed that there was a low inverse relationship between noise exposure and occupational performance of the total workers in all the halls which was statistically significant (P-value = 0/01, r2 = 0/256). It was also found that there was an inverse relationship between exposure to noise and the seven dimensions, but the relationship was statistically significant only for the dimensions of ability, clarity, and evaluation (P-value <0.05). Conclusion: The present study showed that the workers in the pharmaceutical industry and ampoule production line were often exposed to higher-than-permitted sound level, and such exposures had negative effects on their occupational performance.

Search for neutron dark decay: n → χ + e+e−

In January, 2018, Fornal and Grinstein proposed that a previously unobserved neutron decay branch to a dark matter particle (χ) could account for the discrepancy in the neutron lifetime observed in two different types of experiments. One of the possible final states discussed includes a single χ along with an e+e− pair. We use data from the UCNA (Ultracold Neutron Asymmetry) experiment to set limits on this decay channel. Coincident electron-like events are detected with ∼ 4π acceptance using a pair of detectors that observe a volume of stored Ultracold Neutrons (UCNs). We use the timing information of coincidence events to select candidate dark sector particle decays by applying a timing calibration and selecting events within a physically-forbidden timing region for conventional n → p + e- + ν̅e decays. The summed kinetic energy (Ee+e−) from such events is reconstructed and used to set limits, as a function of the χ mass, on the branching fraction for this decay channel.

Decline in peripheral blood NKG2D+CD3+CD56+ NKT cells in metastatic colorectal cancer patients

OBJECTIVE

Colorectal cancer (CRC) is one of the main causes of cancer deaths in the world. This cancer can be divided into non-metastatic and metastatic CRC stages. CD3+CD56+ NKT cell subsets are a minor T cell subset in peripheral blood and conduct the killing of tumor cells in direct manner. Little is obvious about levels and surface markers of these cells such as NKG2D in different cancers, especially in CRC.

METHODS

We included 15 non-metastatic (low-grade), 11 non-metastatic (high-grade), 10 metastatic colorectal cancer patients and 18 healthy controls. The percentages of CD3+CD56+ NKT cells and NKG2D+CD56+ NKT cells from samples were analyzed by flow cytometry in peripheral blood mononuclear cells (PBMCs) of samples.

RESULTS

We found that there was a significantly lower number of NKG2D+CD3+CD56+ cells in peripheral blood of patients with metastatic colorectal cancer compared with normal controls (77.53 ± 5.79 % vs 90.74 ± 9.84 %; p<0.01).

CONCLUSION

The fact that frequency of NKG2D+CD56+ NKT cells was significantly lower in patients with metastatic colorectal cancer compared to healthy controls strengthens the hypothesis that NKT cells can play a substantial role in the protection against human colorectal cancer, and this opens up avenues for novel studies about elucidating the other aspects of tumor surveillance in CRC progression and immunotherapy (Tab. 2, Fig. 2, Ref. 46).

[Significant association between nonsyndromic cleft lip with or without cleft palate and IRF6rs2235371 polymorphism in Iranian familiar population]

According to previous studies the IRF6rs2235371 polymorphism is a risk factor for NSCL/P in different populations. However our recent study revealed no correlation between IRF6rs642961 and NSCL/P in our population. In the present study we have investigated the relationship between IRF6rs2235371 and NSCL/P in same group to determine whether IRF6rs2235371 is a risk factor in our population as well. We analyzed the IRF6rs2235371 genotype in a subset of the Iranian population using the Polymerase Chain Reaction technique. The PCR products were digested with DpnII. Chi-square test was applied to analyze the obtained result. The patients were supplied by the Cleft Lip and Palate Clinic of the Isfahan University of Medical Science. A clinician ascertained the non-syndromic status of all patients and that no clefting drugs, ethanol or smoking were abused during pregnancy. The control group was selected from unaffected subjects with no history of NSCL/P in their families. 107 patients from 107 Iranian unrelated families and 100 controls were screened. There was a significant association between the IRF6rs2235371 genotype sand an increased NSCL/P risk. Our data indicates that the IRF6rs2235371 variation can increase the risk of NSCL/P in the Iranian population. This result is in contrast with the results of our recent study on the correlation between the IRF6rs642961 polymorphism and NSCL/P in the same group.

Surface osteosarcoma: Clinical features and therapeutic implications

INTRODUCTION

Surface osteosarcoma are rare variant of osteosarcoma that include parosteal osteosarcoma, periosteal osteosarcoma and high grade surface osteosarcoma. These lesions have different clinical presentation and biological behavior compared to conventional osteosarcoma, and hence need to be managed differently.

GOAL

The aim of this study is to analyze the clinico-pathological features and outcome of a series of surface osteosarcoma in an attempt to define the adequate treatment of this rare entity.

PATIENT AND METHOD

It is a retrospective and bicentric study of 18 surface osteosarcoma that were seen at the KASSAB's Institute and SAHLOUL Hospital from 2006 to 2013. The authors reviewed the clinical and radiologic features, histologic sections, treatments, and outcomes in this group of patients.

RESULTS

Seven patients were male (38.9%) and 11 were female (61.1%) with mean age of 25 years (range from 16 to 55 years). Eleven lesions were in the femur and 7 in the tibia. We identified 11 parosteal osteosarcoma (six of them were dedifferentiated), 3 periosteal osteosarcoma and 4 high grade surface osteosarcoma. Six patients had neoadjuvant chemotherapy and all lesions had surgical resection. Margins were wide in 15 cases and intra lesional in 3 cases. Histological response to chemotherapy was poor in all cases. The mean follow up was 34.5 months. Six patients (33.3%) presented local recurrence and 8 patients (44.4%) presented lung metastases. Six patients (33.3%) died from the disease after a mean follow up of 12 months (6-30 months); all of them had high grade lesions.

CONCLUSION

Histological grade of malignancy is the main point to assess in surface osteosarcoma since it determines treatment and prognosis. Low grade lesions should be treated by wide resection, while high grade lesions need more aggressive surgical approach associated to post operative chemotherapy.

Surface area: a better predictor of disease severity than the height and volume of the barium column in patients with primary achalasia

OBJECTIVE

Subjective assessment of primary achalasia is not accurate. We aimed to study the utility of surface area of barium retention in the objective assessment of these patients.

METHODS

Subjective and objective esophageal functions of 99 patients with primary achalasia were evaluated initially and 43 of them were reevaluated 1 month after balloon dilation.

RESULTS

Before dilation: Ninety-nine patients were enrolled. Forty-one of them were male. The mean age was 37.5+/-15.3 years. The mean score, resting lower esophageal sphincter pressure, height, surface and volume of barium retention at 5 min were 8.03+/-3.1, 59.1+/-20 mmHg, 9.9+/-4.9 cm, and 23.6+/-13.9 cm and 53.2+/-47.7 cm, respectively. Surface area at 5 min had best correlation and predictive value for resting lower esophageal sphincter pressure. After dilation: Forty-three of 99 patients were reevaluated after balloon dilation. The mean age was 36.8+/-13.6 years. Seventeen of them were male. Mean score, resting lower esophageal sphincter pressure, height, surface area and volume of barium retention at 5 min dropped significantly after dilation. Surface area at 5 min had best correlation and predictive value for lower esophageal sphincter pressure.

CONCLUSIONS

Surface area of barium retention at 5 min is an accurate objective tool to assess patients with primary achalasia. It is cheap and easy to perform; therefore, it could be used more frequently in postdilation follow-up.

Noninvasive markers of liver fibrosis and inflammation in chronic hepatitis B-virus related liver disease

BACKGROUND/AIMS

Noninvasive markers for predicting significant fibrosis and inflammation have not yet been validated in an unselected group of chronic hepatitis B virus (HBV) carriers. The aim of this study was to create noninvasive models to predict significant fibrosis and inflammation in chronic HBV carriers.

METHODS

A total of 276 (229 HBeAg negative, 47 HBeAg positive) unselected consecutive treatment naïve patients chronically infected with HBV who attended our center over a 36-month period underwent liver biopsy. HBeAg negative patients were randomly divided into two cohorts: training group (N = 130) and validation group (N = 99). HBeAg positive patients were analyzed as a whole without separation. Thirteen parameters were analyzed separately in HBeAg negative and HBeAg positive patients to predict significant fibrosis (Ishak stage >or=3) and inflammation (Ishak grade >or=7).

RESULTS

In HBeAg negative patients significant liver fibrosis was best predicted using the variables HBV DNA levels, alkaline phosphatase, albumin, and platelet counts with an area under ROC curve (AUC) of 0.91 for the training group and 0.85 for the validation group. Using the low cutoff probability of 4.72, significant fibrosis could be excluded with negative predictive value of 99% in the entire cohort, and liver biopsy would have been avoided in 52% of patients. The best model for predicting significant inflammation included the variables age, HBV DNA levels, AST, and albumin with an AUC of 0.93 in the training and 0.82 in the validation group. In HBeAg positive patients no factor could predict accurately stages of liver fibrosis, but the best factor for predicting significant inflammation was AST with an AUC of 0.87.

CONCLUSIONS

Significant hepatic fibrosis and necroinflammation can reliably be predicted using routinely checked tests and HBV DNA levels.

Serum hyaluronate as a non-invasive marker of hepatic fibrosis and inflammation in HBeAg-negative chronic hepatitis B

BACKGROUND

HBV infection is a serious global heath problem. It is crucial to monitor this disease more closely with a non-invasive marker in clinical trials. We aimed to evaluate the predictive value of serum hyaluronate for the presence of extensive liver fibrosis and inflammation.

METHODS

28 healthy volunteers and 65 patients with HBeAg negative chronic hepatitis B were enrolled. Liver biopsies scored according to Ishak system. Association of serum hyaloronate with liver fibrosis and inflammation were assessed, and cut off points for serum hyaluronate levels were identified by receiver operating characteristics (ROC) curves and their values for prediction of fibrosis and inflammation were assessed.

RESULTS

In patients with CHB serum hyaluronate had the most significant correlation and predictive values for the liver fibrosis and inflammation comparing to the other variables. At the cut off point of 126.4 ngm/ml it could discriminate extensive fibrosis from milder ones with sensitivity of 90.9% and specificity of 98.1%. With the same value it could discriminate extensive inflammation from their milder counterparts with sensitivity of 63.6% and specificity of 92.6%.

CONCLUSION

Serum hyaluronate was the best predictor of extensive liver fibrosis and inflammation and it could discriminate subgroups of patients with chronic hepatitis B. It could be used as a non-invasive test to monitor these patients more closely with developing anti viral agents in clinical trials.

Lower oesophageal sphincter pressure and timed barium oesophagogram: two objective parameters in the non-invasive assessment of primary achalasia

BACKGROUND

The non-invasive assessment of primary achalasia is not precise.

AIM

To compare investigations before and 1 month after balloon dilation in achalasia.

METHODS

Fifty-two patients with primary achalasia were enrolled. Subjective and objective variables of oesophageal functions were analysed before and 1 month after balloon dilation.

RESULTS

The mean predilation symptom score, lower oesophageal sphincter pressure, height and volume of barium at 5 min were 7.7 +/- 2.6, 62.0 +/- 25.1 mmHg, 9.2 +/- 6.1 cm and 53.2 +/- 49.8 mL respectively; the mean postdilation values were 3.0 +/- 3.0, 34.1 +/- 12.5 mmHg, 7.9 +/- 5.1 cm and 28.0 +/- 30.1 mL respectively. The before dilation volume of barium at 5 min correlates significantly with lower oesophageal sphincter pressure (P < 0.01). The mean symptom scores, lower oesophageal sphincter pressure and volume of barium at 5 min dropped significantly after intervention (P < 0.01), but the reduction in barium height at 5 min was not significant. The percentage changes in volume at 5 min significantly predicted the percentage changes in lower oesophageal sphincter pressure (P < 0.01).

CONCLUSIONS

The volume of barium retention at 5 min can predict the lower oesophageal sphincter pressure before and after balloon dilation in primary achalasia. This could be used as a non-invasive objective tool for initial and post-dilation assessment.

Correlation between clinical severity score and the lower esophageal sphincter relaxation pressure in idiopathic achalasia

OBJECTIVES

Achalasia is an esophageal motor disorder characterized by aperistalsis and incomplete relaxation of the lower esophageal sphincter (LES). The meaningful correlation between LES relaxation pressure and the severity of clinical symptoms is uncertain. The aim of this study was to elucidate the correlation between the clinical scoring and the LES relaxation pressure.

METHODS

Over a 4-yr period from 1997 to 2001, all newly diagnosed patients with idiopathic achalasia were consecutively enrolled in a study. Diagnosis was established based on clinical, radiographic, endoscopic, and manometric criteria. The severity of five cardinal symptoms was scored on a scale of 0-3, and each patient received a total symptom score of 1-15. Manometry was subsequently performed, and the mean of five complete pull-through measurements was recorded as the resting LES relaxation pressure.

RESULTS

A total of 115 patients (67 male and 48 female) with a mean age of 37.7 yr (range 12-90 yr) were included in the study. The mean total symptom score was 9.32 (range 3.00-14.00) and mean LES relaxation pressure before therapy was 56.29 mm Hg (range 8.00-107.80 mm Hg). Linear regression analysis showed a significant association between the total symptom score and LES relaxation pressure (p < 0.002, r = 0.290). Among the main symptoms, active and passive regurgitation showed significant correlation with LES relaxation pressure when compared to other individual symptoms using Pearson's correlation coefficient (p < 0.001 and 0.002, respectively).

CONCLUSIONS

Our study showed that a clinical symptom score can be an appropriate predictor of the LES relaxation pressure in patients with idiopathic achalasia before therapy. Further studies are needed to evaluate similar correlations after therapeutic intervention.

Absence of linkage and linkage disequilibrium to chromosome 15q11-q13 markers in 139 multiplex families with autism

Chromosomal region 15q11-q13 has been implicated to harbor a susceptibility gene or genes underlying autism. Evidence has been derived from the existence of cytogenetic anomalies in this region associated with autism, and the report of linkage in a modest collection of multiplex families. Most recently, linkage disequilibrium with the marker GABRB3-155CA2 in the candidate locus GABRB3, located in this region, has been reported. We searched for linkage using eight microsatellite markers located in this region of chromosome 15 in 147 affected sib-pairs from 139 multiplex autism families. We also tested for linkage disequilibrium in the same set of families with the same markers. We found no evidence for excess allele sharing (linkage) for the markers in this region. Also, we found no evidence of linkage disequilibrium, including for the locus GABRB3-155CA2. Thus, it appears that the role of this region of chromosome 15 is minor, at best, in the majority of individuals with autism.

A genomic screen of autism: evidence for a multilocus etiology

We have conducted a genome screen of autism, by linkage analysis in an initial set of 90 multiplex sibships, with parents, containing 97 independent affected sib pairs (ASPs), with follow-up in 49 additional multiplex sibships, containing 50 ASPs. In total, 519 markers were genotyped, including 362 for the initial screen, and an additional 157 were genotyped in the follow-up. As a control, we also included in the analysis unaffected sibs, which provided 51 discordant sib pairs (DSPs) for the initial screen and 29 for the follow-up. In the initial phase of the work, we observed increased identity by descent (IBD) in the ASPs (sharing of 51.6%) compared with the DSPs (sharing of 50.8%). The excess sharing in the ASPs could not be attributed to the effect of a small number of loci but, rather, was due to the modest increase in the entire distribution of IBD. These results are most compatible with a model specifying a large number of loci (perhaps >/=15) and are less compatible with models specifying </=10 loci. The largest LOD score obtained in the initial scan was for a marker on chromosome 1p; this region also showed positive sharing in the replication family set, giving a maximum multipoint LOD score of 2.15 for both sets combined. Thus, there may exist a gene of moderate effect in this region. We had only modestly positive or negative linkage evidence in candidate regions identified in other studies. Our results suggest that positional cloning of susceptibility loci by linkage analysis may be a formidable task and that other approaches may be necessary.

Exclusion of linkage to the HLA region in ninety multiplex sibships with autism

Several studies have suggested a role for the histocompatibility complex of loci (HLA) in the genetic susceptibility to autism. We have tested this hypothesis by linkage analysis using genetic marker loci in the HLA region on chromosome 6p in multiplex families with autism. We have examined sharing of alleles identical by descent in 97 affected sib pairs from 90 families. Results demonstrate no deviation from the null expectation of 50% sharing of alleles in this region; in fact, for most marker loci, the observed sharing was less than 50%. Thus, it is unlikely that loci in this region contribute to the genetic etiology of autism to any significant extent in our families.

Comparative studies of the CAG repeats in the spinocerebellar ataxia type 1 (SCA1) gene

The CAG repeat tract at the autosomal dominant spinocerebellar ataxia type 1 (SCA1) locus was analyzed in SCA1 families and French-Acadian, African-American, Caucasian, Greenland Inuit, and Thai populations. The normal alleles had 9-37 repeats, whereas disease alleles contained 44-64 repeats. The CAG repeat tract contained one or two CAT interruptions in 44 of 47 normal human chromosomes and in all five chimpanzees examined. In contrast, no CAT interruptions were found in Old World monkeys or expanded human alleles. The number and positions of CAT interruptions may be important in stabilizing CAG repeat tracts in normal chromosomes. At least five codons occupy the region corresponding to the polyglutamine tract at the SCA1 locus in mice, rats, and other rodents. They comprise three or four CCN (coding for proline) in addition to one or two CAG repeats.

Analysis of CAG repeat of the Machado-Joseph gene in human, chimpanzee and monkey populations: a variant nucleotide is associated with the number of CAG repeats

Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative disorder associated with an unstable and expanded CAG repeat. We analyzed this locus from various sources including MJD families, Acadian, African American, Caucasian, Greenland Inuit and Thai populations. The range of the CAG repeat size was 14-40 in the normal alleles while the MJD alleles contained 73-78 repeats in our studies. We found 25 different alleles on normal chromosomes with a heterozygosity of 0.86 in combined populations. The most common alleles were 23 (22.9%) and 14 (25.5%) repeats. We also examined 16 chimpanzees and various Old World monkeys: a pigtail macaque, a mangabey and 12 rhesus macaques. The DNA sequences surrounding the CAG repeat did not vary among species. The range of the number of the CAG repeats is 13-14 in macaques, 16 in mangabey and 14-20 in chimpanzees. Variant CAA or AAG triplets in the CAG repeat tracts were found in all 268 human, 28 monkey and 32 chimpanzee chromosomes. As reported in a previous study [Kawaguchi et al. (1994) Nature Genet. 8, 221-228] the common variant positions were the third (CAA), fourth (AAG) and sixth (CAA) positions. However, we found three human chromosomes containing CAG at the sixth position and the mangabey had AAG at the ninth position. In addition, we found CAG at the fourth position and AAG at the sixth position in all macaque chromosomes. The nucleotide following the CAG repeat tract was usually G in all species studied. However, we sometimes found C at this position in human and chimpanzee chromosomes. Interestingly, this variant C was found in all expanded chromosomes and in 54.5% of chromosomes with 27-40 CAG repeats but it was not found in any chromosomes with less than 20 CAG repeats. We hypothesize that the variant C may be associated with CAG repeat instability.

A locus for axonal motor-sensory neuropathy with deafness and mental retardation maps to Xq24-q26

DNA markers on the X chromosome were used to map the locus for an unusual form of X-linked recessive hereditary motor and sensory neuropathy with associated deafness and mental retardation in a three-generation family that was originally reported by Cowchock et al. (Am, J. Hum. Genet. 35: 85A, 1993; Am. J. Med. Genet. 20: 307-315, 1985). This family included seven affected males, three obligate carrier females, and four unaffected males. The patients were severely affected within the first few years of life with distal weakness, muscle atrophy, sensory loss, areflexia, pes cavus, and hammer toes. Five of the seven affected males showed associated deafness, and three of these five individuals also presented with mental retardation or social developmental delay. Motor nerve conduction velocities in affected males were normal to mildly delayed, and sensory conduction was markedly abnormal. Heterozygous females were asymptomatic. Close linkage to the Xg blood group locus (Xp22) and the PGK locus (Xq13) was previously excluded in this family, while weak linkage of the disease gene to DXYS1 (XQ21.3) was suggested. Our current linkage studies and haplotype analysis of 19 microsatellite markers on the long arm of the X chromosome demonstrate that DXS425 (Xq24) and HPRT (Xq26.1) are flanking markers and that the disease gene is closely linked to the markers DXS1122, DXS994, DXS737, DXS1206, and DXS1047.

The deafness locus (dn) maps to mouse chromosome 19

The deafness mouse has profound sensorineural hearing loss with degeneration of hair cells soon after birth. The mode of inheritance is recessive, and there are no associated phenotypic anomalies. Thus, this mouse provides a model for recessive, non-syndromic, prelingual deafness. We have mapped the gene causing deafness in the mouse to Chromosome (Chr) 19 by analysis of 230 intersubspecific backcross progeny. No recombinants were found with the microsatellite marker D19Mit14. The loci for two guanine nucleotide-binding proteins are tightly linked to this marker, and they are being investigated as possible candidate genes. The identification of the defective gene in the mouse will help to explain the mechanism that causes hair cell degeneration and is likely to identify a homologous gene for deafness in humans.

Mapping of the gene for hormone sensitive lipase (LIPE) to chromosome 19q13.1-->q13.2

Free fatty acids are the major source of fuel for mammals, and hormone sensitive lipase (LIPE) plays a critical role in lipid metabolism by mobilizing free fatty acids from stored triglycerides. We have identified and sequenced a partial cDNA for LIPE. Cosmids were identified by hybridization and mapped to 19q13.1-->q13.2 by FISH. Direct sequence analysis of a 1 kb segment of cosmid 26710 identifies a dinucleotide repeat in an intron upstream of exon 8 of human LIPE. This marker was heterozygous 82% of the time with 12 alleles (166-190 bp) detected in 122 chromosomes. The most likely order for this gene is: qter-[D19S178/LIPE]-(3 cM)-D19S47-(1 cM)-D19S190-RYR1-cen.

A gene for Crouzon craniofacial dysostosis maps to the long arm of chromosome 10

Crouzon craniofacial dysostosis (CFD) is an autosomal dominant craniofacial disorder characterized by premature craniosynostosis, shallow orbits and hypoplastic maxilla. To map the gene responsible, we have used a mapping strategy of testing for linkage to known developmental genes. Analysis of a large kindred established linkage between CFD and three loci (D10S190, D10S209 and D10S216) that span a 13 cM region on chromosome 10q. A maximum pairwise lod score of 4.42 (theta = 0) at D10S190 was obtained and the addition of a second kindred produced a combined pairwise lod score of 5.32 (theta = 0) at the same locus. The developmental gene, PAX2, located within this region, is an attractive candidate gene.

Tightly linked flanking microsatellite markers for the Usher syndrome type I locus on the short arm of chromosome 11

Usher syndrome type I is an autosomal recessive disease characterized by profound congenital hearing impairment and vestibular dysfunction followed by the onset of progressive pigmentary retinopathy in childhood or early adolescence. A locus (USH1C) for one form of this disease was previously assigned to the short arm of chromosome 11 through linkage studies in the Acadian population of southwestern Louisiana. Linkage analyses of a set of microsatellite markers in 27 Acadian families provide evidence that USH1C lies between D11S861 and D11S928. Three markers (D11S419, D11S921, and D11S899) that lie between the flanking markers show no recombination with USH1C, and all 54 chromosomes with the abnormal allele at the disease locus have identical alleles for D11S419 and D11S921. This haplotype was found on only 10 of 50 chromosomes with the normal allele at the disease locus, suggesting a strong founder effect. Of the 54 chromosomes with the abnormal allele, 12 had a divergent allele at D11S899. These results suggest that USH1C is in the 2-3-cM interval between D11S861 and D11S899.

Linkage mapping of the human thromboxane A2 receptor (TBXA2R) to chromosome 19p13.3 using transcribed 3' untranslated DNA sequence polymorphisms

The actions of thromboxane A2 as a prostaglandin mediator are dependent on its recently cloned and sequenced receptor. The identification and characterization of DNA polymorphisms in the thromboxane A2 receptor (TBXA2R) will advance the study of this gene as a candidate in a number of medical disorders. We amplified a 573-nucleotide fragment of the transcribed 3' untranslated region of the TBXA2R gene using the polymerase chain reaction (PCR) and the published cDNA sequence. This region was found to contain two sequence polymorphisms within an Alu. These DNA polymorphisms were demonstrated using an efficient method of direct solid-phase sequence analysis. Three of the four expected alleles were observed in the CEPH families. TBXA2R was localized to chromosome 19 by PCR amplification in a series of monochoromosomal human/rodent somatic cell hybrids. Linkage mapping places TBXA2R closest to the anonymous marker D19S120, with a maximal LOD = 19.55, at a theta = 0.05 in the CEPH panel of DNAs. Multipoint linkage analysis places TBXA2R between the markers D19S120 and PMS207 on the telomeric end of chromosome 19p13.3.

Evidence for genetic heterogeneity in malignant hyperthermia susceptibility

Malignant hyperthermia susceptibility (MHS) is a clinically heterogeneous pharmacogenetic disorder characterized by accelerated metabolism, hyperthermia, and frequently muscle rigidity. MHS is elicited by all commonly used potent inhalation anesthetics and depolarizing neuromuscular blockers and remains an important cause of death due to anesthesia. Recent linkage studies suggest a single genetic locus for this disorder on chromosome 19q13.1. The results of our linkage analyses exclude several loci on 19q13.1 as a site for the gene(s) that produces the MHS phenotype in three unrelated families and clearly establish genetic heterogeneity in this disorder. These results are consistent with the hypothesis that the genetic defect that alters thermoregulation may vary in MHS and that clinical variability in the expression of MHS may be explained by genetic heterogeneity.

Pleiotropic changes in cycloheximide-resistant insect cell clones

Somatic cell mutants resistant to drugs that interact with the eukaryotic ribosome provide a useful tool for studies on ribosome structure, function, and genetics. From Aedes albopictus (mosquito) cells, cycloheximide-resistant mutants (Cx-705 and Cx-738) that were about 30-fold more resistant to cycloheximide than the parental cells have been obtained. The observation that protein synthesis in cell-free lysates from Cx-705 and Cx-738 cells was resistant to cycloheximide led us to suspect that the alteration in these mutants might affect the ribosome. The present studies show that the cycloheximide-resistant cells grow poorly and eventually die at 34.5 degrees C, a temperature at which wild-type cells grow normally. Relative to control cells, the cycloheximide-resistant cells show increased sensitivity to G-418, another antibiotic that interacts with the eukaryotic ribosome. However, there were no differences between cycloheximide-resistant cells and wild-type cells in sensitivity to puromycin, emetine, or cryptopleurine. Cx-705 cells were predominantly diploid; in contrast, the frequency of tetraploid nuclei in Cx-738 cells was about 40%.

Incidence and significance of candiduria

The 100,000 colony count has been used without careful evaluation for the diagnosis of renal candidiasis. Therefore, a prospective study was done on 1,004 urine samples from patients without signs of candidiasis to determine the incidence of candiduria and Candida colony counts. These were compared with colony counts from histologically proved cases of renal candidiasis. The incidence of candiduria varied from a low of 4% in men to a high of 39% in girls during their second week of antibiotic therapy. The overall mean colony count was 1,292 +/- 1,500. The mean colony count in clean-catch urine specimens from six proved cases of renal candidiasis was 23,750 +/- 12,311. The difference in colony counts from proved and unproved cases is statistically significant. Counts greater than 10,000 Candida organisms per milliliter require further investigation.