The size of nanodrugs plays a crucial role in shaping their chemical and physical characteristics, consequently influencing their therapeutic and diagnostic interactions within biological systems. The optimal size of nanomedicines, whether small or large, offers distinct advantages in disease treatment, creating a dilemma in the selection process. Addressing this challenge, size-transformable nanodrugs have surfaced as a promising solution, as they can be tailored to entail the benefits associated with both small and large nanoparticles. In this review, various strategies are summarized for constructing size-transformable nanosystems with a focus on nanotherapeutic applications in the field of biomedicine. Particularly we highlight recent research developments in cancer therapy. This review aims to inspire researchers to further develop various toolboxes for fabricating size-transformable nanomedicines for improved intervention against diverse human diseases.

INTRODUCTIONTo assess the efficacy of screening stools sent for Clostridium difficile cytotoxin assay (CDTA) for surveillance of vancomycin-resistant enterococci (VRE).

MATERIALS AND METHODSFrom April to May 2005, all stools submitted for CDTA were also cultured for VRE using vancomycin containing culture media. Isolates were identified to species level and vancomycin resistance confirmed, followed by polymerase chain reaction (PCR) for detection of vancomycin resistance genes and DNA fingerprinting. Over 2 consecutive days during that period, stool specimens or rectal swabs were also obtained from all patients in high-risk units (haematology, oncology, renal and intensive care). Fifty-one patients in each group were compared in terms of VRE risk factors previously identified.

RESULTS AND DISCUSSIONThe prevalence of VRE in both groups was similar [3/204 (1.5%) in the CDTA arm and 1/97 (1.0%) in the high-risk arm; P = 1.0, Fisher's exact test]. Prevalence of risk factors for VRE colonisation, including age, duration of hospitalisation, exposure to antibiotics, exposure to surgical procedures, presence of malignancy and diabetes mellitus was similar in both groups (P > 0.05). Only renal failure (P < 0.05) was more common in the high-risk group. All 4 isolates of VRE identified were genetically distinct by variable number tandem repeat (VNTR) typing; 3 were Enterococcus faecium (2 with the vanB gene, 1 with vanA) and one E. faecalis.

CONCLUSIONLess than 2% of our high-risk patients are VRE carriers. In-hospital VRE screening using stools sent for CDTA is a simple, reasonable surrogate for screening individual high-risk patients as the patient risk profile is similar and the yield comparable in a low-prevalence setting.

Adult ; Aged ; Clostridium difficile ; isolation & purification ; Cohort Studies ; Enterococcus faecalis ; drug effects ; Feces ; microbiology ; Female ; Health Care Surveys ; Hospitals, Teaching ; Humans ; Male ; Mass Screening ; Middle Aged ; Singapore ; Vancomycin Resistance