Consumo de alcohol, marihuana y cocaína en estudiantes de medicina de la Pontificia Universidad Católica de Chile / Use of alcohol, marijuana and cocaine among medical students of the Pontificia Universidad Católica de Chile

Introducción: El uso de sustancias en adolescentes y adultos jóvenes es un problema importante en Chile. El objetivo de este trabajo es determinar la prevalencia de consumo de alcohol, marihuana y cocaína entre los estudiantes de medicina de la Pontificia Universidad Católica de Chile (PUC), estudiar su relación con ciertas variables psicosociales y contrastar con estudios previos. Métodos: Se diseñó una encuesta voluntaria y de autoreporte, que incluyó el cuestionario "AUDIT" para consumo de alcohol, preguntas de la encuesta de Servicio Nacional para la Prevención y Rehabilitación del Consumo de Drogas y Alcohol (SENDA) para consumo de marihuana y cocaína, y preguntas sobre características sociodemográficas. Resultados: Respondieron 559 estudiantes de un total de 857 (65,2%). La prevalencia de consumo de riesgo de alcohol fue 15,1%, mientras que de consumo perjudicial fue 5,2%. La prevalencia de consumo de marihuana fue 57,2% alguna vez en la vida, 38,2% el último año, y 18,5% el último mes. La prevalencia de consumo de cocaína fue 2,8% alguna vez en la vida, 1,6% el último año, y 0,5% el último mes. Se encontraron asociaciones significativas con las variables estudiadas. Conclusiones: Ha aumentado considerablemente el consumo de sustancias entre los estudiantes de medicina de la PUC. No obstante, la prevalencia es menor si se com-para con el resto de estudiantes de educación superior chilena y similar a lo reportado en estudios de Norteamérica y Europa.

Introduction: The objective of this work is to determine alcohol, cannabis and cocaine use prevalence among medical students from the Pontificia Universidad Católica de Chile, study its relationship with psychosocial variables and, compare our results with previous studies. Methods: A voluntary and self-report survey was designed, which included (AUDIT) for alcohol consumption, questions taken from the National Service for Prevention and Rehabilitation from Alcohol and Drugs ́ (SENDA) Survey for cannabis and cocaine use, and questions about the students ́ sociodemographics. Results: 559 students answered from a total of 857 (65.2%). Risky alcohol use prevalence was 15.1%, and harmful alcohol use prevalence was 5.2%. Cannabis use prevalence was 57.2% ever in their lifetime, 38.2% last year, and 18.5% last month. Cocaine use prevalence was 2.8% ever in their lifetime, 1.6% last year and 0.5% last month. Associations were found between substance use and our studied variables. Conclusions: Substance use among medical students from Pontificia Universidad Católica has risen considerably. However, the prevalence remains low compared to the prevalence in the rest of Chilean higher education students and similar to the reported one from studies in European and North American medical students.

Prevalencia de síntomas depresivos, síntomas ansiosos y riesgo de suicidio en estudiantes de medicina de la Pontificia Universidad Católica de Chile / Prevalence of depressive symptoms, anxious symptoms and risk of suicide among medical students of the Pontificia Universidad Católica de Chile

INTRODUCCIÓN: Los trastornos neuropsiquiátricos tienen una alta prevalencia en Chile, siendo los adolescentes y adultos jóvenes uno de los grupos de mayor riesgo. El objetivo de este trabajo es determinar la prevalencia de síntomas depresivos, ansiosos y riesgo de suicidio en los estudiantes de medicina de la Pontificia Universidad Católica de Chile, con el fin de estudiar su relación con otras variables psicosociales y contrastar con estudios previos. MÉTODOS: se diseñó una encuesta voluntaria y de autoreporte, que incluyó el Cuestionario de Salud General abreviado de Goldberg (GHQ-12), Inventario de Depresión de Beck (BDI), Inventario de Ansiedad de Beck (BAI) y preguntas extraídas de la Encuesta Nacional de Salud sobre riesgo de suicidio. RESULTADOS: respondieron 559 estudiantes de un total de 857 (65,2%). Un 33,6% presentaron GHQ-12 positivo, 66,4% BDI positivo y 34,9% BAI positivo. Sobre riesgo de suicidio, un 19,1% presenta riesgo moderado y un 6,1% riesgo alto. Se encontró asociación con las variables sexo, curso, reprobar algún ramo durante la carrera y evento vital estresante. CONCLUSIONES: los estudiantes de medicina de la Pontificia Universidad Católica presentan mayor prevalencia de síntomas depresivos, síntomas ansiosos y riesgo de suicidio que la población general chilena. Además, nuestros estudiantes presentan tasas mayores en comparación a otros estudios realizados en la misma población durante años previos.

this work is to determine the prevalence of depressive symptoms, anxiety symptoms, and risk of suicide in medical students of the Pontificia Universidad Católica de Chile, to study their relationship with other psychosocial variables and contrast with previous studies. METHODS: a voluntary and self-report survey was designed, which included the Goldberg Abbreviated General Health Questionnaire (GHQ-12), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI) and questions taken from the National Health Survey on suicide risk. RESULTS: 559 students answered from a total of 857 (65,2%). 33,% observed positive GHQ-12, 66,4% positive BDI and 34,9% positive BAI. Regarding suicide risk, 19,1% have moderate risk and 6,1% high risk. An association was found with the variables sex, course, fail some branch during the race and stressful life event. CONCLUSIONS: the medical students of Pontificia Universidad Católica de Chile have a higher prevalence of depressive symptoms, anxious symptoms, and risk of suicide than the general chilean population. Also, our students have higher rates compared to other studies conducted in the same population during previous years.

Obstrucción intestinal por fitobezoar en una paciente con bypass gástrico laparoscópico en Y de Roux: reporte de un caso / Intestinal obstruction due to phytobezoar in a patient with laparoscopic gastric bypass in Roux-en-Y: case report

INTRODUCCIÓN: Los bezoares son una etiología infrecuente de obstrucción intestinal (OI) posterior a un bypass gástrico laparoscópico en Y de Roux (BGLYR). OBJETIVO: Describir un caso clínico de OI debido a un fitobezoar en un sitio infrecuente, en una paciente 2 años después de un BGLYR. CASO CLÍNICO: Paciente de sexo femenino con antecedente de BGLYR hace 2 años y cuadro de obstrucción intestinal causado por fitobezoar. DISCUSIÓN: Se discuten los factores que pueden contribuir a la formación del bezoar en este caso y estrategias para su prevención. Se destaca la importancia del estudio imagenológico y de la exploración quirúrgica oportuna.

BACKGROUND: Bezoars are an infrequent aetiology of bowel obstruction after a laparoscopic Roux-en-Y gastric bypass (LRYGB). OBJECTIVE: To describe a clinical case of bowel obstruction due to a phytobezoar in an uncommon site, in a patient 2 years after a LRYGB. CASE REPORT: A female patient with a history of LRYGB 2 years ago and bowel obstruction due to phytobezoar. DISCUSSION: Factors that can contribute to the formation of bezoar in this case and strategies for its prevention are discussed. The importance of the imaging study and timely surgical exploration is emphasized.

Indicaciones de estudio urodinámico / Indications of urodynamic study

The basic objective of urodynamics is to reproduce the patient's symptoms while evaluating the lower urinary tract directly, with objective quantification of parameters, correlating the symptoms with the findings of the test. Traditionally, it is used: a) to diagnose lower urinary tract dysfunction, quantify its severity and determine the most significant abnormality, b) to predict the consequences of lower urinary tract dysfunction on the upper urinary tract, c) to predict the results of therapeutic interventions and possible complications and d) to investigate the causes of treatment failures. In this article we will refer to the indications of urodynamics taking into account the recommendations of the main international urological societies: 1) in women with urinary incontinence, with emphasis on those who have stress urinary incontinence and who will undergo surgery, 2) in men with non-neurogenic lower urinary tract symptoms suggestive of benign prostatic hyperplasia, and 3) in patients with neurologic involvement of the lower urinary tract ("neurogenic bladder"), considering the classification of neurological disorders according to the risk over the upper urinary tract. (AU)

Do Age and Religion Have an Impact on the Attitude to Organ Transplantation?

BACKGROUND: Religious issues may be a significant reason for the lack of organs for transplantation. Younger people have a more enthusiastic attitude toward organ donation. The goal of the present study was to determine whether age and religion affect people's attitudes to organ transplantation. METHODS: This trial was a diagnostic poll study using an original survey questionnaire involving 1273 people living in Podlaskie Voivodeship. RESULTS: Treatment with the use of organs from dead donors was approved by 88.3% of the respondents aged ≤60 years and 70.5% of those aged >60 years; the highest number of those who opposed this procedure occurred in the group aged >60 years (22.3%). Baptists approved of the method more often than persons of other religions; Muslims disapproved of it more often than others (25%). Approximately 96% of the participants, regardless of religion, had a positive attitude toward organ transplantation, but only 81% aged >60 years had a positive attitude toward organ donation; there were significantly more Catholics in this group (P < .026). In the group aged >60 years, 63.8% expressed their consent; 66.7% of them were Muslims and Baptists. Approximately 86% of persons aged ≤60 years were willing to donate their own organs after death. These people were significantly more often Catholic (P < .045). CONCLUSIONS: Age and religion have a considerable influence on positive attitudes toward transplantation. The majority of younger people, as well as Catholics, approve of the removal of organs from living donors and from dead donors.

Opinions and Attitudes of University Students Concerning Organ Transplantation.

INTRODUCTION: Organ donation and transplantology are receiving more and more support and approval all over the world every year. However, there remains a considerable and growing difference between the number of patients awaiting transplantation and the number of donors. The aim of the work was to find out the opinions and attitudes of university students concerning organ donation and transplantology. MATERIAL AND METHODS: Our poll surveyed 405 students from 2 universities (Medical University of Bialystok [MU] and Bialystok University of Technology [UT]). The research tool used in the study was an original survey questionnaire. RESULTS: Treatment with the use of organs taken from living persons was approved by 55.6% of the students, from dead donors, by 73.6%, and 1.2% of the participants did not approve of that way of treatment. Of the students from the MU, 84% approved the removal of organs from close relatives after their death; 79.5% of those from the UT approved. Of the UT students, 8% were against the removal of organs from close relatives after their death; 4% of MU students were against it. Of MU students 94.5%, would agree to have their own organs removed after death; 85.3% of UT students would agree. Of MU students, 54.2% of students had informed their families about their will to have organs removed; 29.4% of UT students had informed their families. A greater number of medical students had a declaration of will (28.9% vs 13.2%; P < .001). The kind of university had a significant (P = .002) influence on the students' attitudes to transplantation. A positive attitude was displayed by 94.5% of MU students and 83.8% of UT students, whereas a negative one, by 2% of UT students and 0.5% of MU students. CONCLUSIONS: Different degrees of knowledge and acceptance of organ donation were manifested by university students. To a great extent, this depended on the kind of university. MU students understood the topic and approved of the treatment to a greater degree. A permanent educational campaign should be carried out among young people, especially those studying at universities other than medical.

Evaluación clínica del paciente con síntomas del tracto urinario inferior / Clinical evaluation of the patient with lower urinary tract symptoms

Lower urinary tract symptoms are divided into three groups, storage, voiding and post micturition symptoms. Their level of agreement with urodynamic investigation is poor. Clinicalhistory should be complemented by the application of validated symptom questionnaires and the recording of urinary events. Here we refer to: a) the International Consultation onIncontinence Questionnaire, Short Form (ICIQ-SF), b) the Urogenital Distress Inventory - Short Form (UDI-6) and Incontinence Impact Questionnaire – Short Form (IIQ-7), c) the urinary incontinence Severity Index and d) the American Urological Association Symptom Index. The recordings of urinary events can be done in three main forms: a) micturition time chart, b)frequency volume chart, and c) bladder diary. The International Consultation on Incontinence Questionnaire bladder diary (ICIQ bladder diary) is the only one validated. Physical exam should include abdominal and genital examination, covering pelvic organ prolapse quantification in women, prostate evaluation in men, pelvic floor muscle function evaluation in both genders, and a neurologic examination focused on evaluation of the sacral nerves. It is useful to supplementthe physical examination with the evaluation of the mobility of the bladder neck and proximal urethra through the Q-tip test, and with the quantification of urine leakage through the pad test.

Attitudes of members of the Baptist Church toward organ transplantation.

INTRODUCTION: The Baptist Church in Poland has not presented its official stance on organ, tissue, or cell transplantation so far. The aim of the work was to find out Baptists' knowledge and opinions concerning organ transplantation. METHODS: The respondents were 296 members of the Baptist Church. The research tool used in the study was an original survey questionnaire. RESULTS: The vast majority of Baptists (72%) would agree to have organs removed from a deceased family member. The fact of knowing someone who has had an organ transplanted was a factor promoting such a decision. Three fourths of the respondents would agree on removal of their organs for transplantation after death, but only 47% have talked about that with their families. Of the respondents, 37% think that the transplant recipient should have the opportunity to meet the family of the donor. The respondents who did not agree to have organs removed from a deceased person most often mentioned such reasons as aversion to violating bodily integrity of the deceased person (55%), religious beliefs (54%), failure to agree with the death of the deceased person (46%), not knowing the deceased person's will (34%), and lack of trust in health service (32%). CONCLUSION: Propagation of knowledge of transplantation is the only effective method of increasing the number of organ transplantations, because many ethical, social, and religious barriers in the society result from insufficient education.

Opinions of town residents on organ transplantation.

INTRODUCTION: Organ transplantation is connected with many very difficult ethical and social issues that evoke a lot of emotion. The aim of this work was to determine the knowledge and opinions of the 612 residents of selected towns in Podlaskie voivodeship (in northeastern Poland) on organ transplantation. MATERIAL AND METHODS: A diagnostic poll with the use of a survey questionnaire was implemented in the study. The respondents were divided into 2 groups (towns <100,000 and >100,000 residents). RESULTS: Respondents from larger towns were more often willing to donate organs of close relatives for transplantation than those from small towns (67.1% vs 32.9%; P = .022). Respondents with higher education levels accepted organ donation from close relatives after their death significantly often than those with no more than a primary education (46.7% vs 22.2%; P < .001). Of the respondents, 83% would agree to donation after death and to donating their own organs (higher with primary education, 90.6% vs 63.5%; P < .001). Of respondents from big towns, 61.0% have informed their family of the decision for donation after death compared with 38.5% of respondents from small towns. Respondents with higher education significantly more often informed their family of such decision than persons with primary education (60.9% vs 42.9%; P < .007). CONCLUSIONS: More emphasis should be on educating the communities living in small towns and people with primary and vocational education, because an adequate level of knowledge is a significant factor influencing the readiness to give one's organs for transplantation.

Renal function after percutaneous coronary interventions depending on the type of hydration.

PURPOSE: The aim of our study was to evaluate renal function assessed by serum creatinine as well as novel biomarkers in 142 patients with stable coronary heart disease and normal serum creatinine undergoing percutaneous coronary interventions (PCI) depending on the type of hydration: physiological saline vs. sodium bicarbonate (1:1 randomization). MATERIALS AND METHODS: Serum and urinary NGAL were evaluated before and after 8-12, and 24 hours after PCI. Serum cystatin C, serum creatinine, estimated glomerular filtration rate using different formulae were assessed before PCI, and 24 hours after the procedure. RESULTS: Only 2 patients (2.8%) from the saline-hydrated group fulfilled the criteria for CI-AKI. In patients hydrated with sodium bicarbonate serum creatinine declined significantly (p<0.01). In patients hydrated with sodium bicarbonate a significant fall in serum NGAL after 8-12 hours was found. In sodium bicarbonate group cystatin C decreased non significantly after 8-12 hours, then returned to the baseline values. In patients hydrated with physiological saline serum NGAL before PCI and after 24 hours correlated positively with cystatin C and eGFR by CKD-EPI. In patients hydrated with sodium bicarbonate baseline serum NGAL correlated with NGAL baseline cystatin C and eGFR by CKD-EPI, similarly serum NGAL after 24 hours correlated with cystatin C. CONCLUSION: We suggest to rather use sodium bicarbonate in a hydration protocol in patients undergoing PCI. However, the value of NGAL in this setting remains to be elucidated and volume expansion remain the unquestionable prevention methods of CI-AKI.

Blood pressure control according to the prevalence of diabetes in renal transplant recipients.

Hypertension is one of the most frequent complications of renal transplantation. About 70% to 90% of this population display either high blood pressure (BP) or require antihypertensive therapy. Diabetes mellitus is also a common finding among kidney transplant recipients. The aim of the study was to assess the BP control among kidney transplant recipients according to the prevalence of diabetes. This retrospective analysis included 172 renal transplant recipients of overall mean age 50 years and 51% males. Hypertension was present in 79% of patients. About one-third of the studied population showed abnormal blood pressures based on office measurements. The cohort was divided into two groups according to the presence of diabetes: group 1, diabetic patients (n = 14) versus group 2, nondiabetics (n = 158). Nondiabetic patients were significantly older than diabetic ones (61.5 versus 49 years; P < .05) and their time after renal transplantation was longer (98.83 versus 67.33 months, P < .05). There was no difference in regard to hypertension prevalence, mean BP value, percentage of abnormal (≥ 140/90 mm Hg) BP values or glomerular filtration rate. Diabetic patients were prescribed less steroid. The main hypotensive drug used in whole cohort and in no-diabetic patients was a beta-blocker (n = 64, 37%; n = 4, 28%), patients with diabetes used beta-blockers and angiotensin-converting enzyme inhibitors at the same frequency (n = 60, 37%). The main causative factor for hypertension appeared to be the calcineurin inhibitor. More aggressive antihypertensive treatment using combined drugs, including RAS blockers, might provide adequate BP control among renal transplant subjects with high cardiovascular risk.

Compliance with lifestyle recommendations in kidney allograft recipients.

BACKGROUND: Many factors affect long-term graft and patient survival. Compliance with lifestyle recommendation may be an important factor. Lifestyle modifications may play a therapeutic and protective role against graft failure and possible death. METHODS: The aim of this work was to assess compliance with lifestyle recommendations among 110 kidney allograft recipients. All patients were asked to complete a questionnaire regarding life style, frequency of outpatient visits, self-control, diet, physical activity and addictions. RESULTS: The mean age of the population was 48.79±13.18 years, and their mean time after transplantation was 69±44.5 years with a mean serum creatinine value of 1.45±0.7 mg/dL. Physicians were the major source of information (40%) for patients while in the hospital; nurses informed patients in only 5.5% of cases. The majority of patients (97.5%) attended regular outpatient clinic visits. A similar percentage of subjects regularly measured their blood pressure at home. One-fifth of the patient wrote a self-control diary. Only 55.5% of patients knew the immunosuppressive regimen, including the doses of the medications. An overweight condition was diagnosed in 39%, with obesity in 22%; 16% of the patients were smokers; one-fourth of the patients drank alcohol at least several times a month; 85.3% of patients did not change their diet after kidney transplantation; and one-half of the patients (64.2%) were not aware of dietary recommendations after kidney transplantation. CONCLUSIONS: The majority of patients regularly attended the outpatient clinic and ingested immunosuppressive medications. However, their knowledge regarding diet, cancer prophylaxis, and self-control was insufficient. Therefore, there is a need to introduce more intense organizational and educational activities to improve patient knowledge.

Blood pressure control in orthotopic heart transplant and kidney allograft recipients is far from satisfactory.

Hypertension is widely accepted as a risk factor for coronary artery disease, heart failure, stroke, or chronic kidney disease. According to ESH/ESC and JNC guidelines, the target blood pressure should be low 140/90 mm Hg in the general population, and 130/80 mm Hg among patients with chronic kidney disease or diabetes. The aim of this study was to assess the prevalence of achieved target blood pressure among 164 prevalent heart transplant recipients as well as 172 prevalent, kidney transplant, 100 hemodialyzed, and 50 peritoneally dialyzed patients on renal replacement therapy. We assessed kidney function in transplanted patients using the simplified MDRD formula. In the heart transplant (OHT) population, 10% had diabetes and 65% chronic kidney disease; in the kidney transplant population 18% had diabetes. Hypertension was treated in 70% of OHT, 92% of kidney 90% of hemodialyzed and 70% of peritoneally dialyzed patients. In the OHT population, only 43% of subjects achieved the target blood pressure, while 42% among kidney transplant, 50% of hemodialzyed, and only 20% of peritoneally dialyzed patients did so. Hypertensive OHT as well as kidney transplant subjects were older, displayed higher serum creatinine values and lower estimated glomerular filtration rates. Hypertensive patients after OHT were treated with ACE inhibitors (50%), calcium channel blockers (55%), diuretics (34%), ß-blockers (34%), and/or spironolactone (5%). Among hypertensive kidney allograft recipients, the most commonly used drugs were calcium channel blockers (80%), ß-blockers (60%), diuretics (55%) ACE inhibitors (40%), and α-blockers (12%). The kidney transplant population required three and more hypotensives in 63% of cases. Despite polytherapy optimal blood pressure control was not achieved in the majority of patients. OHT and kidney graft recipients displayed a high prevalence of hypertension, which should be treated adequately. More efforts must be dedicated to optimize blood pressure control, particularly in the presence of other comorbidities.

Present data on organ donation and transplantation in Poland.

At present, organ transplantation activity in Poland is located in the middle among European Union countries. There are appropriate law regulations, well-organized legal structures, well-educated transplant teams, good transplantation results, and case registries. There are 24 organ transplant teams in 20 centers, including 46 programs. Since 1966, over 18,000 organs have been transplanted 14,300 kidneys; 1800 livers; 1700 hearts; 250 kidney/pancreases and 30 lungs. Every year almost 1500 organs are procured from about 500 cadaveric heart-beating donors (9-14 per million people [pmp]) with 50 from living donors: 800 to 1000 kidneys (21-28 pmp); over 200 livers (5-6 pmp); and 60 to 100 hearts (1.6-2.7 pmp). National transplant registries are maintained in Poltransplant including a central registry of refusals (the policy of presumed consent with registered objection on donation after death is implemented), waiting lists, a cadaveric and living donor registry, and a transplant registry. There are still some actions that should be undertaken to strengthen the transplantation system in Poland, to increase organ availability, to enhance the efficiency and accessibility of transplantation systems, and to improve quality and safety: namely, increasing deceased donations to their full potential, appointing transplant coordinators in every hospital where there is the potential for organ donation, promoting quality improvement programs, and promoting living donation.

Arginine and proline genes of Aspergillus niger.

Aspergillus niger mutants defective in arginine or proline biosynthesis have been isolated and 12 genetic loci were identified. Mutation was induced by low doses UV, and mutants were isolated after filtration enrichment. The mutants were classified according to their phenotype in growth tests and were further characterized in complementation tests. The arginine auxotrophic mutants represent nine complementation groups. Three additional complementation groups were found for mutants that could grow on proline (two of them on arginine too). Linkage group analysis was done in somatic diploids obtained from a mutant and a master strain with genetic markers on six chromosomes. The arg genes belong to six different linkage groups and the pro genes to two. One arg-mutant could be complemented by transformation with the A. nidulans argB+ gene, and this A. niger gene thus appeared to be homologous to the A. nidulans argB. We isolated an A. niger strain with the argB gene tightly linked with the nicA1 marker. This strain is very suitable as acceptor for transformation with an argB-plasmid, because transformants with inserts on the homologous site can be recognized and analyzed genetically using the nicA1 marker gene.

Adenine and pyrimidine genes of Aspergillus niger and evidence for a seventh linkage group.

Mutants of Aspergillus niger requiring adenine and one mutant requiring cytosine were isolated after low-dose mutagenesis and enrichment. In addition we had mutants of two genes involved in the pyrimidine biosynthesis isolated as 5-fluoro-orotic acid-resistant mutants. The fifteen adenine-less mutants could be placed in seven complementation groups. From each group a representative mutant was analyzed in order to determine the linkage group by analysis of the mutants in a heterozygous diploid carrying markers in six linkage groups. AdeF could not be assigned to any one of these linkage groups and proved to be linked to nicB, oliC and cnxC, none of which could be placed in a linkage group. Thus, conclusive evidence was obtained for a seventh linkage group. As pyrA was used as selection marker for transformation, we constructed a pyrA strain with a linked marker which can be used in the genetic analysis of transformations.

Genetic analysis and the construction of master strains for assignment of genes to six linkage groups in Aspergillus niger.

A start has been made on establishing a collection of Aspergillus niger colour and auxotrophic mutants with an isogenic background for use as a source of genetic markers. All strains have short conidiophores (csp A1), which makes them easy to handle on test plates. Genetic markers were combined stepwise by somatic recombination. Somatic diploids were obtained at frequencies of 10(-6) -10(-5) with conidiospores collected from a heterokaryon. The haploidization of heterozygous diploids was induced by benomyl. For unlinked markers, the frequency of recombinants varied from 35%-65%. Low frequencies of recombinants were found between markers on a same chromosome, but this was sometimes disturbed by mitotic crossing-over during an early stage of the diploid. Master strains were constructed having markers for six linkage groups.