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41.

Background

The methylotrophic yeast, Pichia pastoris, offers the possibility to generate a high amount of recombinant proteins in a fast and easy way to use expression system. Being a single-celled microorganism, P. pastoris is easy to manipulate and grows rapidly on inexpensive media at high cell densities. A simple and direct method for the selection of high-producing clones can dramatically enhance the whole production process along with significant decrease in production costs.

Results

A visual method for rapid selection of high-producing clones based on mannanase reporter system was developed. The study explained that it was possible to use mannanase activity as a measure of the expression level of the protein of interest. High-producing target protein clones were directly selected based on the size of hydrolysis holes in the selected plate. As an example, the target gene (9elp-hal18) was expressed and purified in Pichia pastoris using this technology.

Conclusions

A novel methodology is proposed for obtaining the high-producing clones of proteins of interest, based on the mannanase reporter system. This system may be adapted to other microorganisms, such as Saccharomyces cerevisiae for the selection of clones.  相似文献   
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The pain phenotype in sickle cell disease (SCD) patients is highly variable. A small percentage of SCD patients experience many vaso-occlusive crises/year, 5% of patients account for over 30% of pain episodes, while 39% report few episodes of severe pain. Clearly, a better understanding of the pathobiology of SCD is needed to improve its therapy. Humanized sickle cell mice recapitulate several phenotypes of SCD patients and provide a model for the study of SCD pain. Researchers have shown that one strain of humanized SCD mice, the BERK strain, has abnormal pain phenotype. However, the nociception phenotype of another humanized SCD mouse strain, the Townes strain, has not been described. In a large cross-sectional study of BERK and Townes SCD mice, we examined thermosensory response and sensory nerve fiber function using sine-wave electrical stimulation at 2000, 250, and 5 Hz to stimulate preferentially Aβ, Aδ, and C sensory nerve fibers, respectively. We found that BERK and Townes mice, compared to respective controls, had decreases in 2000, 250, and 5 Hz current vocalization thresholds in patterns that suggest sensitization of a broad spectrum of sensory nerve fibers. In addition, the pattern of sensitization of sensory fibers varied according to strain, sex, age, and mouse genotype. In a similarly variable pattern, Townes and BERKs also had significantly altered sensitivity to noxious thermal stimuli in agreement with what has been shown by others. In summary, the analysis of somatosensory function using sine-wave electrical stimulation in humanized sickle cell mice suggests that in SCD, both myelinated and unmyelinated, fibers are sensitized. The pattern of sensory fiber sensitization is distinct from that observed in pain models of neuropathic and inflammatory pain. These findings raise the possibility that sensitization of a broad spectrum of sensory fibers might contribute to the altered and variable nociception phenotype in SCD.  相似文献   
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A study of renal biopsy specimens obtained in Senegal from 24 children and six adults with nephrotic syndrome showed two unusual varieties of nephropathy--namely, an extramembranous glomerulonephritis associated with hypocomplementaemia (four cases), a combination previously described only in systemic lupus erythematosus, and a "tropical nephropathy" (16 cases). The latter, though lacking the diffuse glomerular deposits of immunoglobulin described in quartan malarial nephropathy (Q.M.N.), showed a curious progressive and segmental glomerulosclerosis, characterized by a "flaking" or fibrillary splitting of the glomerular capillary wall, seen in Q.M.N. Serological evidence of malaria was lacking in a third of the childhood cases.  相似文献   
46.
We investigated cytological changes in oral mucosa smears from patients treated with cryotherapy to determine whether cryotherapy prevented mucositis caused by 5-fluorouracil (5-FU) therapy. Patients with gastrointestinal malignancies were divided into four groups; control patients before 5-FU therapy, patients after 5-FU therapy without cryotherapy, patients with cryotherapy before 5-FU therapy and patients with cryotherapy after 5-FU therapy. Oral mucosa samples from all patients were assessed at the beginning and on day 14 of chemotherapy. We used exfoliative cytology to evaluate cellular changes in the oral mucosa that were caused by 5-FU. Smears from each patient were stained using the Papanicolaou method and analyzed using stereology. Smears were taken from each group before and after 5-FU infusion. We found that nuclear volume was decreased significantly in cells of the 5-FU therapy after cryotherapy patients compared to the 5-FU therapy before cryotherapy patients. We also found significantly decreased cytoplasmic volumes in the 5-FU therapy after cryotherapy patients compared to the 5-FU therapy before cryotherapy patients. The results of cytomorphometric estimations revealed that cryotherapy may be used to prevent damage to oral tissue and may decrease the frequency and duration of oral mucositis caused by 5-FU.  相似文献   
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48.

Objective

To describe an unusual case of a urethral foreign body.

Methods and results

This was a case of an intraurethral foreign body in a man aged 32 with previous psychiatric problems, who had inserted an electric cable into his urethra. This was managed by surgical removal via a perineal approach.

Conclusion

The treatment of intraurethral foreign bodies is usually endoscopic, but in some cases open surgery is necessary.  相似文献   
49.

Objectives

To describe the epidemiological, clinical and therapeutic characteristics of penile fracture in the department of Urology-Andrology of h?pital général de Grand Yoff, Dakar, Sénégal.

Materials and methods

We reviewed the medical records of cases of penile fracture managed at the h?pital général de Grand Yoff from January 2001 to December 2011. The data of interest were: age at diagnosis, geographic origin, clinical presentation, surgical findings, treatment and outcomes.

Results

In ten years, 25 cases of penile fracture were found with an average of 2,5 cases per year and patients mean age of 36 years with 22 and 60 years as extremes. The circumstances of occurrence were mainly forced manipulation (52%) and coitus (32%). Pain associated with penile curvature, swelling localized to the penis or extending to the pubis or the perineum were the major clinical findings. A prompt emergency (mean time for providing care was 2 hours ranging from 45 minuts to 2 days) surgical explorationwith suture of the albuginea of the corpus cavernosum was the treatment in all cases.

Conclusion

Penile fracture is a relatively uncommon urological emergency in our setting. The diagnosis is easy, mostly based on clinical examination. A prompt and appropriate surgical management is the key to cosmetic and functional outcomes.  相似文献   
50.

Methodology

This was a transverse randomized survey of subjects over the age of 18 years. Subjects completed a self-administered questionnaire composed of two parts. The first part contained information on demographic characteristics, associated diseases, erectile dysfunction and associated sexual disorders and the second part was based on IIEF5. Two groups were identified: a group with erectile dysfunction (ED group) and another group without erectile dysfunction (No ED group). Differences between the two groups were considered to be statistically significant for p ≤ 0.05 on the Chi-square test.

Results

The global prevalence of erectile dysfunction was 26%. The prevalence by age-group revealed a progressive increase of ED with age from 11% between 20 and 30 years to 76% between 70 and 80 years. The rate of polygamous men was significantly higher in the group with ED (29.2%) compared to the group without ED (6.6%) (p < 0.0001) and the severity of ED increased in relation to the number of wives. Chronic alcoholism was significantly more frequent in the group with ED (p = 0.023). The frequency of ED increased with the duration of cigarette smoking from 11.9% for less than 5 years, 16.9% between 5 years and 10 years and 71.2% for more than 10 years. Some diseases (diabetes, hypertension and depression) were significantly more frequent in the group with ED. Analysis of the type of ED revealed that secondary erectile dysfunction was more frequent (95.6%) than primary erectile dysfunction (4.4%). Associated sexual disorders were significantly more frequent in the group with ED.  相似文献   
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