Purpose: The aim of this study was to compare the hepatitis B surface antibody (HBs Ab) titer 1 month after the 4th dose of hepatitis B vaccine administration on the large and appropriate for gestational age infants. Materials and Methods: This cross-sectional study was conducted on 7-month-old cases (n=132) divided into two groups of 2–4 kg (group 1: appropriate for gestational age, 63 cases) and >4 kg (group 2: large for gestational age, 69 cases), whom were vaccinated with a fourdose schedule of hepatitis B vaccine in 2016, Tehran, Iran. Results: Mean birth weight of the groups was 2.98±0.528 and 4.19±0.190 kg, respectively.Hepatitis B surface antigen and hepatitis B core antibody were negative in all cases. HBs Ab level in group 1 and 2 was 13,701.00±11,744.439 and 8,997.15±2,827.191, respectively (95% confidence interval of difference, -7,607.44 to -1,800.25). There was a significant difference between the two groups in antibody titration and antibody logarithm level (p=0.002, p=0.0001). Conclusion Birth weight may affect the response to the hepatitis B virus vaccine administration.

Objective: Chronic scrotal hyperthermia (SHT) can lead to serious disorders of the male reproductive system, with oxidative stress playing a key role in the onset of these dysfunctions. Thus, we evaluated the impact of caffeine, a potent antioxidant, on cellular and tissue disorders in mice with chronic SHT. Methods: In this experimental study, 56 adult male NMRI mice were allocated into seven equal groups. Apart from the non-treated control group, all were exposed to heat stress. Two groups, termed “preventive” and “curative,” were orally administered caffeine. The preventive mice began receiving caffeine immediately prior to heat exposure, while for the curative group, a caffeine regimen was initiated 15 consecutive days following cessation of heat exposure. Each treated group was subdivided based on pairing with a positive control (Pre/curative [Cur]+PC) or a vehicle (Pre/Cur+vehicle). Upon conclusion of the study, we assessed sperm characteristics, testosterone levels, stereological parameters, apoptosis, antioxidant and oxidant levels, and molecular markers. Results: Sperm parameters, testosterone levels, stereological parameters, biochemical factors (excluding malondialdehyde [MDA]), and c-kit gene expression were significantly elevated in the preventive and curative groups, especially the former, relative to the other groups. Conversely, expression levels of the heat shock protein 72 (HSP72) and nuclear factor kappa beta (NF-κβ) genes, MDA levels, and apoptotic cell density were markedly lower in both caffeine-treated groups relative to the other groups, with more pronounced differences observed in the preventive group. Conclusion Overall, caffeine attenuated cellular and molecular abnormalities induced by heat stress in the testis, particularly in the mice treated under the preventive condition.