Let $t_p(G)$ denote the number of paths in a graph $G$ and let $f:E\rightarrow \mathbb{Z}^+$ be an edge labeling of $G$. The weight of a path $P$ is the sum of the labels assigned to the edges of $P$. If the set of weights of the paths in $G$ is $\{1,2,3,\dots,t_p(G)\}$, then $f$ is called a Leech labeling of $G$ and a graph which admits a Leech labeling is called a Leech graph. In this paper, we prove that the complete bipartite graphs $K_{2,n}$ and $K_{3,n}$ are not Leech graphs and determine the maximum possible value that can be given to an edge in the Leech labeling of a cycle.

Objective: The principle of the use of Leeches is associated with traditional medicine of many countries and its application has different philosophies for use in different areas of the body. Leeches, with all the benefits, can have dangers. Materials and Methods: A review of complications of Leech therapy was done based on English articles indexed in the databases up to July 1, 2018. A strategic search has done independently by members of the research team and then all of the articles were +categorized by subject. Results: Related articles were mostly case-reports. Complications were divided into five categories including infection, allergy, prolonged bleeding, migration, and others. Infection is the most-reported complication related to Leech therapy and Aeromonas spp. has the most participation in infections. Conclusion: Leech therapy can be a therapeutic complementary method if the possible complications are managed properly.

A 67-year-old myopic man presented to the Ophthalmology Department of a teaching hospital in the mountainous state of Sikkim with complaints of red eye, ocular discomfort, and sensation of something moving in his right eye that lead to occasional visual blurring from the previous four days. His symptoms started after washing his face in a stream. Clinical diagnosis was a Leech in the limbus of the right eye at the 12 o’clock position. Ocular Leech infestation should be considered in a patient with a history of swimming or face washing in streams and lakes. Herein we report a case of ocular Leech infestation that presented as red eye with intermittent blurring of vision in the affected eye, and discuss the differential diagnosis and clinical significance.

Our reportable case was a 13 years old girl who comes from Zahedan and was reflected to hospital. because of A.U.B. She had spotting or moderate vaginal bleeding from two weeks ago. She had called on Physicians in this period and was treated with oral contraceptives and progestin's, none of these. medications were effective. In physical examination a little black lump was seen in the proximal port of the vagina. This mass was extracted by forceps. Surprisingly it was a Leech. After a short time her vaginal bleeding was stopped.

Purpose: To report a case of adult ocular Leech infestation.Case report: A 67-year-old male presented to the emergency department of Farabi Eye Hospital with the complaint of bloody tear. Slitlamp biomicroscopy of left eye revealed bloody lashes, bloody tear and a large black green foreign body attached to the inferotemporal bulbar conjunctiva. One cc of lidocaine 2% was injected directly to the body of Leech. 10 minutes after injection, removal with forceps was retried.Conclusion: Ocular Leech infestation must be considered as a differential diagnosis of bloody tear and hemorrhagic conjunctivitis. Removal of Leech after direct injection of lidocaine to its body seems to be a safe method.