Allele specific-PCR and melting curve analysis showed relatively high frequency of ß-casein gene A1 allele in Iranian Holstein, Simmental and native cows.

There are two allelic forms of A1 and A2 of ß-casein gene in dairy cattle. Proteolytic digestion of bovine ß-casein A1 type produces bioactive peptide of ß-casomorphin-7 known as milk devil. ß-casomorphin-7 causes many diseases, including type 1 diabetes, cardiovascular disease syndrome, sudden death and madness. The aim of the present study was to determine the different allelic forms of ß-casein gene in Iranian Holstein, Simmental and native cattle in order to identify A1 and A2 variants. The blood samples were collected randomly and DNA was extracted using modified salting out method. An 854 bp fragment including part of exon 7 and part of intron 6 of ß-casein gene was amplified by allele specific polymerase chain reaction (AS-PCR). Also, the accuracy of AS-PCR genotyping has been confirmed by melting temperature curve analysis using Real-time PCR machinery. The comparison of observed allele and genotype frequency among the studied breeds was performed using the Fisher exact and Chi-squared test, respectively by SAS program. Obtained results showed the A1 allele frequencies of 50, 51.57, 54.5, 49.4 and 46.6% in Holstein, Simmental, Sistani, Taleshi and Mazandarani cattle populations, respectively. The chi-square test was shown that no any populations were in Hardy-Weinberg equilibrium for studied marker locus. Comparison and analysis of the test results for allelic frequency showed no any significant differences between breeds (P>0.05). The frequency of observed genotypes only differs significantly between Holstein and Taleshi breeds but no any statistically significant differences were found for other breeds (P>0.05). A relatively high frequency of ß-casein A1 allele was observed in Iranian native cattle. Therefore, determine the genotypes and preference alleles A2 in these native and commercial cattle is recommended.

Postoperative adjuvant chemotherapy and radiotherapy for cancer of the large bowel and rectum.

Forty patients with invasive regional-stage adenocarcinoma of the large bowel and rectum received adjuvant postoperative chemotherapy combined with doses of radiation below the maximal tissue tolerance level. This treatment was reserved for patients with stage B2, C1, and C2 lesions, with only two exceptions. The treatment was well tolerated. It appeared to result in a longer disease-free interval when compared with population-based results for patients with sigmoid cancer who had surgery alone. Our results paralleled those of the Gastrointestinal Tumor Study Group (GITSG) for combined adjuvant therapy of rectal cancer, who also indicated an advantage for long-term survival. Patients who received additional extended chemotherapy had at least the same percentage of favorable outcomes. Tumors above the peritoneal reflection also appeared to share the same improved results. We believe a multicenter randomized study should be performed to evaluate this group of patients.

Combined preoperative neoadjuvant radiotherapy and chemotherapy for anal and rectal cancer.

Neoadjuvant therapy combining 5-fluorouracil, mitomycin C, and moderate-dose radiotherapy was given preoperatively to 29 patients with adenocarcinoma of the rectum, 3 patients with squamous cell cancer, and 1 patient with basaloid carcinoma of the anus. Significant downstaging, and even eradication, of these lesions was realized in a high percentage of cases. Population-based data for the period of 1979 to 1984 which encompasses the time of our study indicate the survival of those treated by the neoadjuvant therapy was superior to that of patients treated by surgery alone or by surgery followed by radiotherapy. In general, patients with the poorest clinical presentation had been referred for this therapy.

Preoperative radiation and chemotherapy for anal and rectal cancer.

It became apparent on review of the recent literature that the combination of radiation therapy and chemotherapy may offer increased response in patients wih locally advanced carcinomas of the anus and rectum. The protocol for this group is 1 week of chemotherapy with 3 weeks or radiation, followed by 3 to 6 weeks later by surgical intervention. In this limited group of 10 patients, considerable benefit was noted. All of the lesions decreased dramatically in size, with 8 of the 10 patients showing more than a 50 percent decrease. Only 1 of the 10 patients showed evidence of nodal involvement at the time of surgery. Three of the patients showed no evidence of tumor and three others showed microscopic tumor only. While the number of patients is small and follow-up is still short, the study seems to have shown the same improved results which have been reported by others using similar protocols. If our long-term follow-up remains equally satisfactory, then the concept of low dose drug therapy combined with radiation could have broader implications, and perhaps be extended to other neoplastic diseases with the same excellent tolerance. This form of therapy can be provided in the setting of a community cancer center, where radiation therapy and medical oncology services are available as an adjunct to surgery.