Cryptosporidium in humans and animals-a one health approach to prophylaxis

Cryptosporidium is a major cause of moderate-to-severe diarrhoea in humans worldwide, second only to rotavirus. Due to the wide host range and environmental persistence of this parasite, cryptosporidiosis can be zoonotic and associated with foodborne and waterborne outbreaks. Currently, 31 species are recognized as valid, and of these, Cryptosporidium hominis and Cryptosporidium parvum are responsible for the majority of infections in humans. The immune status of the host, both innate and adaptive immunity, has a major impact on the severity of the disease and its prognosis. Immunocompetent individuals typically experience self-limiting diarrhoea and transient gastroenteritis lasting up to 2 weeks and recover without treatment, suggesting an efficient host antiparasite immune response. Immunocompromised individuals can suffer from intractable diarrhoea, which can be fatal. Effective drug treatments and vaccines are not yet available. As a result of this, the close cooperation and interaction between veterinarians, health physicians, environmental managers and public health operators is essential to properly control this disease. This review focuses on a One Health approach to prophylaxis, including the importance of understanding transmission routes for zoonotic Cryptosporidium species, improved sanitation and better risk management, improved detection, diagnosis and treatment and the prospect of an effective anticryptosporidial vaccine.

Study of the Efficacy of Real Time-PCR Method for Amikacin Determination Using Microbial Assay

PURPOSE

Microbial assay is used to determine the potency of antibiotics and vitamins. In spite of its advantages like simplicity and easiness, and to reveal the slight changes in the molecules, the microbial assay suffers from significant limitations; these methods are of lower specificity, accuracy and sensitivity. The objective of the present study is to evaluate the efficacy of real time-PCR technique in comparison with turbidimetric method for microbial assay of amikacin.

METHODS

Microbial determination of amikacin by turbidimetric method was performed according to USP. Also amikacin concentrations were determined by microbial assay using taq-man quantitative PCR method. Standard curves in different concentration for both methods were plotted and method validation parameters of linearity, precision and accuracy were calculated using statistical procedures.

RESULTS

The RT-PCR method was linear in the wider concentration range (5.12 - 38.08 for RT-PCR versus 8.00 - 30.47 for turbidimetric method) with a better correlation coefficient (0.976 for RT-PCR versus 0.958 for turbidimetric method). RT-PCR method with LOQ of 5.12 ng/ml was more sensitive than turbidimetric method with LOQ of 8.00 ng/ml and the former could detect and quantify low concentrations of amikacin. The results of accuracy and precision evaluation showed that the RT-PCR method was accurate and precise in all of the tested concentration.

CONCLUSION

The RT-PCR method described here provided an accurate and precise technique for measurement of amikacin potency and it can be a candidate for microbial determination of the antibiotics with the same test organism.

Zeta potential vs apoptotic marker: which is more suitable for ICSI sperm selection?

PURPOSE

Selection of appropriate sperm is considered as a decision making point in the ICSI procedure. Canonically, sperm selection is based on morphology and motility. Recent advances in this field, have shown that, this procedure can be assisted by further selection based on membrane surface charge (Zeta potential) and surface apoptotic marker (phosphatidylserine externalization) using magnetic activated cell sorter (MACS). Based on the literature, both these procedures improve quality of selected sperm population. Therefore, this study aims to compare the efficiency of these two procedures.

METHODS

Semen samples were collected from 36 fertile and infertile (teratozoospermic and /or asthenozoospermic) individuals. Sperm DNA fragmentation, protamine deficiency and morphology were assessed by TUNEL, CMA3 and papanicolaou staining in unprocessed, MACS and Zeta processed samples.

RESULTS

Although both MACS and Zeta were able to separate a higher percentage of sperm with normal morphology, and lower DNA fragmentation and protamine deficiency compared to unprocessed, MACS procedure could significantly isolate, a greater percentage of sperm with normal acrosome and protamine content compared to Zeta procedure.

CONCLUSION

Both MACS and Zeta procedures improve the quality of the selected spermatozoa for ICSI. However, MACS procedure is more efficient in individuals with severe male factor infertility to select sperm with normal acrosome and protamine content but concern regarding transfer of MACS beads into the oocyte remains to be resolved.

Technical aspects and results of the transhiatal resection in adenocarcinomas of the gastroesophageal junction

The distribution of lymph node metastases of adenocarcinomas of the gastroesophageal junction is classified into three types. The R0 resection with complete lymphadenectomy therefore requires different resection methods for type 1 and type 2/3 tumors. Comparing the subtotal esophagectomy and the extended gastrectomy, no advantage in survival can be seen for one method or one tumor type (type 1 or type 2/3). The same is true for the lethality. Indeed, the transhiatal resection is accompanied by a higher complication rate. However, the different operation methods for cardiacarcinomas, with subtotal esophagectomy in type 1 and extended gastrectomy in type 2/3 tumors, should be maintained because of increased rates of local recurrence that may be expected if all cardiacarcinoma types were treated using subtotal esophagectomy with gastric tube interposition. Therefore, we suggest a subtotal esophagectomy only in type 1 tumors. In type 2/3 tumors, an extended gastrectomy with resection of the distal esophagus, lymphadenectomy of the lower mediastinum, and D2 lymphadenectomy should be performed.

Distinct clonal composition of primary and metastatic adrencorticotrophic hormone-producing pituitary carcinoma

The pathogenetic mechanisms underlying pituitary tumorigenesis are largely unknown. Previous reports have suggested that aggressive pituitary adenomas and/or carcinomas may be associated with genetic alterations that are distinct from those responsible for the more common and less aggressive pituitary adenomas. Here, we describe the clonal composition of a pituitary carcinoma, its recurrence and its metastasis. The samples studied were from a 48-year-old woman who presented with recurrent Cushing's syndrome. During the 8-year course of her disease, she had an ACTH-producing pituitary carcinoma requiring two transsphenoidal procedures and resection of a metastatic cervical lymph node. Her disease remained active despite surgical resection, external beam irradiation and medical treatment with ketoconazole. Ultimately, bilateral adrenalectomy was performed to control the hypercortisolism. Morphological and immunohistochemical studies revealed that the primary and recurrent pituitary tumours and the metastatic lesion were an endocrine tumour with ACTH and growth hormone immunoreactivity. Primary, recurrent and metastatic tumour DNAs were analysed for X-chromosome inactivation and loss of heterozygosity (LOH) at several microsatellite loci on chromosomes 9,10, 11, 13 and 22. All three lesions were monoclonal in composition as suggested by the pattern of X chromosome inactivation of the PGK-1 allele. Moreover, the primary, recurrent and metastatic lesions demonstrated LOH at the microsatellite allelic markers PYGM and D10S217. In contrast, however, the metastatic lesion showed a loss-to-retention pattern at two distinct loci (IFNA and D22S156) compared to the primary and recurrent pituitary tumours. These findings, while consistent with a clonal composition of the primary and metastatic pituitary lesions, show each clone to be distinct. This is the first description of a metastatic pituitary carcinoma with a distinct clonal composition from its primary source.

Absence of heart rate increase during inferoposterior left ventricular hypoperfusion caused by dipyridamole infusion

BACKGROUND

Stimuli such as inferoposterior myocardial infarction and right coronary injection with radiographic contrast media evoke a vasodepressor reflex characterized by bradycardia and hypotension (Bezold-Jarisch reflex). Dipyridamole acts by adenosine-mediated coronary vasodilation to disclose myocardial perfusion heterogeneity for thallium-201 scintigraphy.

OBJECTIVE

To determine whether there is a relationship between the site of left ventricular hypoperfusion and the heart rate response to dipyridamole.

DESIGN

One thousand eight hundred consecutive dipyridamole-thallium studies performed between 1985 and 1993 were reviewed to identify 48 subjects who met prespecified selection criteria.

SETTING

Nuclear cardiology laboratory of a university teaching hospital.

PATIENTS

Group 1 (n=26) had less than 5% pretest likelihood of coronary artery disease and normal thallium perfusion, group 2 (n=10) had isolated, completely reversible anterior perfusion abnormalities, and group 3 (n=12) had analogous inferoposterior perfusion abnormalities.

INTERVENTIONS

Heart rate and blood pressure were recorded at baseline and each minute of supine dipyridamole infusion.

MAIN RESULTS

After 4 mins of dipyridamole infusion, a significant increase in heart rate was observed in group 1 (+12 beats/min, P<0.05) and group 2 subjects (+12 beats/min, P<0.05) but not in group 3 subjects (+3 beats/min, not significant; P=0.016 compared with responses in the other two groups). Blood pressure was not affected by dipyridamole infusion in any group.

CONCLUSIONS

Isolated, moderate or severe inferoposterior hypoperfusion in response to dipyridamole is not accompanied by an increase in heart rate, suggesting that the chronotropic response to dipyridamole is modulated by the presence and location of myocardial perfusion abnormalities. This observation is consistent with the concept that inhibition of adenosine reuptake by dipyridamole, leading to local increases of adenosine concentration, exerts direct and/or reflex effects on heart rate that are site specific. The absence of a rise in heart rate during dipyridamole infusion may be a marker of impaired coronary flow reserve in the inferoposterior left ventricular wall.

Successful treatment of chloral hydrate cardiac toxicity with propranolol

A case of chloral hydrate overdose causing resistant ventricular arrhythmias is presented. Our case and other case reports suggest that chloral hydrate-induced arrhythmias are resistant to standard antiarrhythmic agents and that intravenous beta blockers should be the firstline treatment for these arrhythmias.