Fast and precise diagnostic techniques are required for the treatment of many disorders. Biosensors are one of the diagnostic devices that are applicable in biological and medical sciences. Biosensors could be utilized to recognize biological molecules with high sensitivity. Biosensors are consisted of different components and have different types. Each type of biosensor is used in a particular field according to its specific features. Nanobodies are a novel class of antibodies with small size, high affinity, and specificity to their target. The unique properties of nanobodies make them appropriate tools for diagnostic applications. In this paper, we review biosensors, and their features and roles in medicine. Antibody/nanobody-based biosensors are also specifically discussed.

Objective: To explore the effect of Persea americana supplementation on inflammation, oxidative stress, and lipid profiles in ovariectomized rats fed with a high-fat diet and exposed to radiation. Methods: The control group was sham operated, while groups 2-5 were ovariectomized and fed a high-fat diet. Groups 4 and 5 were exposed to γ-radiation (1 Gy/week for 5 weeks) after ovariectomy. Groups 3 and 5 were treated with 1 mL/250 g/day of Persea americana for one month. Serum levels of estrogen, alanine aminotransferase, aspartate aminotransferase, cholesterol, triglycerides and lipoproteins were measured. Additionally, hepatic oxidative stress, inflammatory and fibrogenic markers were evaluated. Results: Persea americana treatment reduced the oxidative stress markers as well as the levels of triglyceride, total cholesterol, and low-density lipoprotein cholesterol, which in turn lowered hepatic fat accumulation. Moreover, it suppressed hepatic inflammatory mediators (interleukin-6, tumor necrosis factor-α, and C-reactive protein) and downregulated pro-fibrogenic markers (transforming growth factor-β and tissue inhibitor of metalloproteinase-1). Conclusions: Persea americana provides protection against ovariectomy, and gamma radiation-mediated hepatic inflammation not only through its antioxidant, anti-inflammatory, lipid-lowering effect but also by modulating the fibrogenic markers.

Objective: To explore the effect of Persea americana supplementation on inflammation, oxidative stress, and lipid profiles in ovariectomized rats fed with a high-fat diet and exposed to radiation. Methods: The control group was sham operated, while groups 2-5 were ovariectomized and fed a high-fat diet. Groups 4 and 5 were exposed to γ-radiation (1 Gy/week for 5 weeks) after ovariectomy. Groups 3 and 5 were treated with 1 mL/250 g/day of Persea americana for one month. Serum levels of estrogen, alanine aminotransferase, aspartate aminotransferase, cholesterol, triglycerides and lipoproteins were measured. Additionally, hepatic oxidative stress, inflammatory and fibrogenic markers were evaluated. Results: Persea americana treatment reduced the oxidative stress markers as well as the levels of triglyceride, total cholesterol, and low-density lipoprotein cholesterol, which in turn lowered hepatic fat accumulation. Moreover, it suppressed hepatic inflammatory mediators (interleukin-6, tumor necrosis factor-α, and C-reactive protein) and downregulated pro-fibrogenic markers (transforming growth factor-β and tissue inhibitor of metalloproteinase-1). Conclusions: Persea americana provides protection against ovariectomy, and gamma radiation-mediated hepatic inflammation not only through its antioxidant, anti-inflammatory, lipid-lowering effect but also by modulating the fibrogenic markers.

Objective: To explore the mechanism of drug resistance in acute lymphoblastic leukemia and the anti-tumor effect of combination therapy of dehydroabietic acid and vincristine against acute lymphoblastic leukemia cells. Methods: Acute lymphoblastic leukemia cells REH and CCRF- CEM were employed to detect the anti-tumor effect of vincristine and doxorubicin on proliferation and apoptosis using EdU assay, human active caspase-3 Quantikine ELISA kit, and flow cytometry. Vincristine-resistant REH cells (REH-R), survivin knockdown and overexpressing REH cells were established to verify the role of survivin in drug resistance. Additionally, in vitro and in vivo assays were performed to determine the effect of dehydroabietic acid on the cytotoxicity of vincristine. Results: Vincristine and doxorubicin markedly suppressed proliferation and induced apoptosis of REH and CCRF-CEM cells. Survivin expression was upregulated in REH-R cells compared with REH cells. Knockdown of survivin expression obviously restored the sensitivity of REH-R cells to vincristine. Akt phosphorylation was also increased in REH-R cells compared to REH cells. In addition, LY294002, a PI3k/Akt pathway blocker, inhibited survivin expression and enhanced cytotoxicity of vincristine to REH-R cells. Dehydroabietic acid effectively reduced survivin expression in REH-R cells, thereby enhancing the therapeutic effect of vincristine on drug-resistant cells. Survivin overexpression markedly reduced the effect of dehydroabietic acid on enhancing the anti-proliferation and inducing apoptosis effect of vincristine. Moreover, the combination of dehydroabietic acid with vincristine significantly extended the survival rate in a mouse xenograft model of acute lymphoblastic leukemia, compared with vincristine treatment alone. Conclusions: Dehydroabietic acid may be used as a potential candidate for the treatment of acute lymphoblastic leukemia in combination with vincristine.

Objective: To evaluate the photoprotective, antioxidant, antiglycation, and antiacne activities of crude extract (CESs) and triterpene saponin fraction (TSSs) of Sapindus saponaria. Methods: HPLC-MS purification was performed on a Symmetry TM C18 column. The saponins were identified by a UV detector. Antioxidant activity was evaluated by DPPH and O₂^- radicals scavenging, and FRAP and TBARS assays. Glycation activity was assessed by relative electrophoretic mobility and inhibition of advanced glycation end products (AGEs) formation. Additionally, antiacne activity was determined by inhibition of Cutibacterium acnes, and photoprotective effect was evaluated by Mansur’s method. Results: Most of the triterpene saponins detected in the fraction by HPLC-MS analysis were hederagenin as the aglycon. CESs and TSSs presented varying antioxidant activity in DPPH (CESs: 75.69% and TSSs: 83.65%), FRAP (CESs: 425.39 μM TE/g DW and TSSs: 649.36 μM TE/g DW), TBARS (CESs: 42.96% and TSSs: 52.16%) and O₂^- radicals scavenging (CESs: 61.33% and TSSs: 86.69%) tests. CESs and TSSs also exhibited antiglycation activity comparable to bovine serum albumin treated with aminoguanidine. In addition, CESs and TSSs showed inhibition of AGE formation (34.48% and 61.85%, respectively). Antiacne activity against Cutibacterium acnes was observed with a minimum inhibitory concentration equal to minimum bactericidal concentration (CESs: 36.11 μg/mL and TSSs: 18.34 μg/mL). In photoprotective assays, CESs and TSSs showed maximum absorbance of 1.42 to 0.20 and 2.80 to 1.30, respectively, in the wavelength range of 260 to 400 nm. Furthermore, CESs and TSSs showed sun protection factors of 8.89 and 14.89, respectively. Conclusions: Sapindus saponaria fruit extracts show strong antioxidant potential and antiglycation activity against bovine serum albumin glycation and AGE formation. Besides, they presented antibacterial activity against Cutibacterium acnes and photoprotective effect against UV-A and UV-B.

Objective: To investigate anti-multidrug resistance (MDR) activity and safety of the bioactive fraction (CL11) from Codiaeum luzonicum crude leaf extract. Methods: Cytotoxic activity of CL11 against MDR and non- resistant colon cancer cells was assessed using MTT assay. Mode of cell death was investigated by annexin V-propidium iodide staining, TUNEL, and JC-1 assays. To examine mechanism of action, the effect on the expression and function of the MDR-implicated protein P-glycoprotein was tested using Western blotting and calcein assay, respectively. Results: CL11 had an EC₅₀ of 0.18, 1.03 and 38.52 μg/mL against HCT-15, HCT-15/Dox and HCT116, respectively. Cytotoxicity was mediated by inhibition of P-glycoprotein function and expression. The mode of cell death involved mitochondrial membrane depolarization and was mostly non-apoptotic at EC₅₀ concentrations against HCT-15 and HCT-15/Dox. Conclusions: Fraction CL11 of Codiaeum luzonicum induces non- apoptotic cell death in MDR cancer cells by overcoming MDR through inhibition of P-glycoprotein expression and function.