Genetic diversity and drug resistance of Mycobacterium tuberculosis in Ecuador

BACKGROUND

The genetic diversity of Mycobacterium tuberculosis in Quito, Ecuador is not well known.

OBJECTIVE

To investigate mutations related to drug resistance and bacterial genotypes in M. tuberculosis strains in Ecuador.

DESIGN

This was a retrospective study of M. tuberculosis isolates from 104 patients. Isolates were phenotypically resistant to rifampicin (RMP) and/or isoniazid (INH). The genotype was determined using 24-locus mycobacterial interspersed repetitive units-variable-number tandem repeats (MIRU-VNTR).

RESULTS

Isolates showed mutations in the rpoB and katG genes, and the inhA promoter. In rpoB, we found 13 genetic alterations at codons 511, 513, 514, 515, 516, 526 and 531. Forty-six (44.2%) RMP-resistant isolates belonged to codon 531. In katG, there were nine genetic alterations at codons 296, 312, 314, 315, 322, 324 and 351. Fifty-three (51%) INH-resistant isolates belonged to codon 315. Five mutations not previously described were identified in katG: Thr324Ser, Thr314Ala, Ala312Pro, Trp351Stop and deleted G at 296 codon. The Latin American Mediterranean (LAM) (33.7%) and Ghana (30.8%) lineages presented most of the main mutations observed.

CONCLUSION

This is the first report from Ecuador; it describes five new mutations in katG and indicates that LAM is the most prevalent lineage.

From alcohol to delusional jealousy

Purpose

With this clinical case we want to show an example of diagnosis and treatment of a frequent psychiatric comorbidity in alcohol dependence: delusional jealousy.

Methods

We analyzed a clinical case of a 52-year-old man who has a voluntary drug intake promoted by a delusional jealousy to his wife in a context of chronic alcohol consumption. A bibliographic search is made about the comorbidity of delusional jealousy in alcoholism.

Results

A 52 year-old man is brought to the hospital after to have a voluntary drug intake. He has not got medical history of mental health. As personal antecedents, the harmful alcohol consumption of the last 6 years in which he is unemployed is highlighted. After the clinical interview with the patient and with direct relatives (woman and daughter), we have the suspicion that it is a case of cellotipia induced by alcohol, in which the patient has made an autolytic attempt fomented by a delusion of jealousy. In this moment treatment is started. After a few weeks in which the patient starts treatment and leaves alcohol consumption, delusional clinic of jealousy refers progressively.

Conclusions

The alcoholic etiology of cellotipia has not been specifically confirmed. However, clinical experience shows this association is extremely frequent. It's a chronic delusional disorder with content of jealousy, providing interpretations and suspicions unfounded. Is added hostility to his partner, with potential risk of heteroagresivity. The most important thing is to assess the emotional and behavioral resonance of delirium. The treatment consists of indicating abstinence from alcohol and administration of neuroleptics.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Phylogeography and molecular epidemiology of Papaya ringspot virus

Papaya ringspot virus (PRSV) is the most important virus affecting papaya and cucurbit plants in tropical and subtropical areas. PRSV isolates are divided into biotypes P and W: both the P and W types naturally infect plants in the family Cucurbitaceae, whereas the P type naturally infects papaya (Carica papaya). Understanding the origin and nature of the PRSV genetic diversity and evolution is critical for the implementation of control strategies based on cross-protection and the deployment of transgenic plants that show resistance to virus isolates highly similar to the transgene. The molecular epidemiology of PRSV was evaluated by analyzing the nucleotide sequence of the capsid protein (CP) and helper component-proteinase (HC-Pro) genes of isolates from around the world, including newly characterized ones from Colombia and Venezuela, using a relaxed molecular clock-based approach and a phylogeographic study. Our results confirm previous estimates on the origin of PRSV around 400 years ago and suggest distinct dispersion events from the Indian Peninsula to the rest of Asia, via Thailand, and subsequently to the Americas. A historical reconstruction of the P- and W-type characters in the phylogenetic study supports the need to revise the hypothesis that PRSV-P derives from PRSV-W since our results suggest that the ancestral state could be either of the two biotypes. Moreover, estimates of epidemic growth predict an increasing genetic diversity of the virus over time that has direct implications for control strategies of PRSV based on cross-protection and the use of transgenic plants.

Spatial and emotional memory in aged rats: a behavioral-statistical analysis

Age-related impairment in synaptic plasticity, like long-term potentiation (LTP), has been repeatedly reported. We had shown that late stages of LTP in the rat dentate gyrus can be modulated by emotional factors, but this is impaired by aging. In the present study we have searched for possible impairments in emotional and spatial memory tasks that may correspond to the impaired reinforcement observed at the cellular level. We have trained young and aged animals in a battery of tests: exploration (open field) object recognition, anxiety (plus maze) fear conditioning and spatial memory (Morris' water maze (MWM)). The open field, anxiety, and novelty recognition showed no age differences except a reduced velocity in aged rats. Emotional and contextual memories were preserved, but acquisition was slightly impaired. Age-dependent impairments appeared in spatial memory, evaluated in terms of latency and distance to reach the hidden escape platform in the water maze task, but these were not related with impairments in other tests, in particular there was no relation between spatial and emotional memory impairments. Age-related impairments in different paradigms were caused by different independent factors that did not correlated with each other.

Varying genetic diversity of Papaya ringspot virus isolates from two time-separated outbreaks in Jamaica and Venezuela

Coat protein sequences of 22 Papaya ringspot virus isolates collected from different locations in Jamaica and Venezuela in 1999 and 2004, respectively, were determined and compared with sequences of isolates from earlier epidemics in 1990 and 1993. Jamaican isolates collected in 1999 exhibited nucleotide sequence identities between 98 and 100% but shared lower identities of 92.2% with an isolate collected in 1990. Isolates from the 2004 epidemic in Venezuela exhibited more heterogeneity, with identities between 88.7 and 98.8%. However, isolates collected in 1993 were more closely related (97.7%). The viral populations of the two countries are genetically different and appear to be changing at different rates; presumably driven by introductions, movement of plant materials, geographical isolation, and disease management practices.

Detection of Bm86 antigen in different strains of Boophilus microplus and effectiveness of immunization with recombinant Bm86

The control of tick populations by using conventional strategies poses several problems, including the appearance of organophosphate resistant strains, among others. The possibility of using alternative strategies such as vaccination with tick antigens has been suggested by several authors. One particular antigen (Bm86) has been described and shown to be able to induce a protective immunity against the cattle tick Boophilus microplus. In this paper we demonstrate by means of immunohistochemical staining that this antigen is conserved among several strains of this species. These results correlate with those showing that animals vaccinated with a preparation of recombinant Bm86 were protected against challenge with the four different strains tested, including one resistant to organophosphates. These results favour the immunization with recombinant Bm86 for the control of the cattle tick B. microplus.

[Gastric cancer and routine upper digestive endoscopy]

In this paper we analyzed 5,401 upper G.I. endoscopies performed in a period of 5 years (1985-89), in the Gastroenterology Service at Hospital Jesús Yerena, in Caracas, Venezuela. We found 53 cases of stomach cancer, only 2 of them were early gastric cancer. We studied personal and epidemiological data, symptoms, place of the lesion, treatment, surgical mortality, macroscopic morphology and histopathology. We discuss the results concluding that: cancer of the stomach is a prevalent disease in our Hospital; that fibrogastroscopy is a very good diagnostic procedure; that we must organize a Program of Early Detection for this disease and that we should improve the Oncological Register.

[Adenomatous polyps in colon and rectum after cholecystectomy]

The frequency of rectal and colonic polyps was compared in 33 patients with history of cholecystectomy and 37 patients without it. The data were evaluated retrospectively from our medical bank records. We found a major incidence of adenomatous polyps in the group of patients with cholecystectomy, the same in females as in males, with a female prevalence in 2.7:1 ratio in contrast with the group without surgery, where the ratio was 1.5:1 with a male prevalence. We didn't find any association between cholecystectomy and colorectal cancer. All the patients with adenocarcinoma were in the group without cholecystectomy.