Occurrence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis among captive mammals in the Bangladesh National Zoo

Cryptosporidium and Giardia are protozoan parasites capable of causing gastrointestinal illness in humans and animals. The purpose of this research was to determine the occurrence, genetic characteristics, and zoonotic potential of Cryptosporidium spp. and Giardia duodenalis in captive mammals at the Bangladesh National Zoo. A total of 200 fresh fecal samples from 32 mammalian species were collected and examined for Cryptosporidium spp. using nested polymerase chain reaction (PCR) targeting the small subunit (SSU) rRNA gene and G. duodenalis targeting the β-giardin (bg), glutamate dehydrogenase (gdh), and triosephosphate isomerase (tpi) genes. The overall infection rates of Cryptosporidium and G. duodenalis among captive mammals in the zoo were 3.5% (7/200) and 5.5% (11/200), respectively. Five species/genotypes of Cryptosporidium (C. hominis, C. andersoni, C. muris, C. felis, and Cryptosporidium deer genotype) were identified. C. hominis was subtyped as IbA12G3 by sequence analysis of the glycoprotein 60 (gp60) gene. Multilocus genotyping of G. duodenalis revealed assemblages A, B, and D. Mixed infections of assemblages B and D and A and B were found in an Asiatic jackal and a Nilgiri langur, respectively. To our knowledge, this is the first report on the occurrence and genetic identity of the two parasites among zoo animals in Bangladesh. The results suggest that zoonotic Cryptosporidium spp. and G. duodenalis are maintained in and transmitted between captive mammals. Therefore, washing, cleaning, and disinfection measures should be implemented to reduce the spread of Cryptosporidium and G. duodenalis infections.

Cervical lymph node metastasis in squamous cell carcinoma of the buccal mucosa: a retrospective study on pattern of involvement and clinical analysis

BACKGROUND

The study was performed with an aim to map the pattern of metastasis of squamous cell carcinomas of buccal mucosa to various cervical lymph node levels and analyze its correlation with primary tumor size and histo-pathological grading.

MATERIAL AND METHODS

254 patients with squamous cell carcinoma of the buccal mucosa treated with surgery first approach were analyzed retrospectively. The tumor size was noted from pre-operative CT Scans and were divided into early and advanced tumors. The resected specimen was studied to note the histo-pathological grading of the squamous cell carcinoma and the metastatic deposits at various lymph node levels.

RESULTS

Out of 254 patients (149 females, 105 males), 145 patients showed histo-pathologically proven metastatic deposits in one or more lymph nodes out of which there were 56 patients showing occult metastasis. 78/145 patients showed metastatic involvement of level IB and/or IA lymph nodes, 31 showed involvement of level II and/or I lymph nodes, 27 showed involvement of level III with or without involvement of level I and II and 9 showed metastasis to level IV and V lymph nodes with or without level I, II or III lymph nodes. Cervical lymph node metastasis had statistically significant association with tumor size with advanced tumors showing worse pattern of metastatic spread beyond level I and II lymph nodes. As the degree of differentiation of squamous cell carcinoma reduced, they were more prone for cervical metastasis with moderately and poorly differentiated squamous cell carcinoma showing higher involvement of level III, IV and V lymph nodes.

CONCLUSIONS

The majority of buccal mucosa cases showed metastasis to level I, II and III lymph nodes out of which level IB and/or IA was most frequently involved. Metastasis to level IV and V lymph nodes was rare and was seen especially in patients with advanced primary tumor and poor histo-pathologic differentiation.

Natural history and prognosis of ischemic heart disease

Forty-four cases with myocardial rupture (33 with free wall rupture, 9 with interventricular septal perforation and 2 with papillary muscle rupture), all of which were ascertained by autopsy and/or at surgery, were analyzed. When the following 7 risk factors were actively managed in the acute stage of myocardial infarction, the incidence of myocardial rupture was significantly reduced: a) high blood pressure on admission, b) physical and emotional instability, c) recurrent chest pain, d) aged females, e) no history of angina or myocardial infarction, f) large myocardial infarction on ECG and g) the first 10 days after the attack of myocardial infarction. If cardiogenic shock occurs, surgery should be performed as soon as possible; if not, it should be delayed 3 weeks. The natural history of ischemic heart disease was analyzed in 400 medically-treated patients with significant coronary artery disease. They had been followed up continuously and periodically for more than one year. The prognosis of the patients with 3-vessel disease or left main trunk disease, those with poor left ventricular function (EF less than 30%) and of old age (greater than or equal to 60) and those who had a history of ischemic heart disease was poor. Follow-up study was done in 30 patients with variant angina. They often had life-threatening arrhythmias during attacks (8 ventricular tachycardia or ventricular fibrillation, 8 serious bradyarrhythmia). All patients with variant angina should be treated medically at first, and only patients with organic coronary artery disease and chest pain on effort in spite of the medical treatment should be considered as candidates for AC bypass surgery.