When Iran and the United States found some common ground at the negotiating table earlier this month, it gave Naghmeh Abedini a welcome glimmer of hope.
Her husband, Christian pastor Saeed Abedini, a dual U.S.-Iranian citizen, has been imprisoned in Iran since 2012 on charges of threatening the country's national security through private religious gatherings.
Could the prospect of a final nuclear deal between Tehran and world powers help secure his release?
So far, she told RFE/RL, not only has there been no improvement in his situation, it has gotten worse.
"We just know that, pretty much a few days after the deal was reached, he was threatened and harassed by guards more," she said.
The precise reasons for this are not clear. The answer could be a relatively simple case of Abedini's guards carrying out a personal vendetta. Or it could be much more complex, and serve as a defiant hard-line statement against improved relations with the United States.
In recent months, longstanding tensions between the two countries have significantly eased. But while hard-liners have been supportive of the nuclear negotiations, they have made it clear they don't want to see moves toward normalized relations.
While the release of Saeed Abedini and other Americans is not up for discussion in the ongoing nuclear talks, for Naghmeh Abedini, their outcome holds the key to her husband's fate.
"If a deal is reached, there's better relations and we're hoping that would mean Iran would let my husband go free," she told RFE/RL in a telephone interview. "But if somehow, for some reason, no deal is reached, that is bad news."
"This is the best chance for Iran to show good-faith effort by releasing Saeed and other Americans," Naghmeh Abedini added.
Iranian-American Amir Hekmati, a former U.S. marine, has been held in Iran on espionage charges since 2011.
Pawn In Nuclear Negotiations?
The family of former U.S. Marine is also hoping that a nuclear deal could help lead to his release, a spokeswoman told RFE/RL. Hekmati, a dual U.S.-Iranian national, has been in jail in Iran since August 2011 on espionage charges.
Amy Mueller, the coordinator of the "Free Amir" campaign, said Hekmati has been told by Iranian authorities that his case is dependent on the outcome of the nuclear negotiations.
"There's been indications even made to Amir by some Iranian officials that the deal is really attached to it," Mueller said. "He's basically a bargaining chip attached to that deal."
It is also believed that the case of Washington Post bureau chief Jason Rezaian is tied to the outcome of the nuclear talks and infighting in Iran over improved relations with the United States.
Rezaian, who was detained in Iran nine months ago, was this week charged with espionage and three other security crimes, including "collaborating with hostile governments."
Before being formally charged, hard-line media -- including the Fars news agency, which is affiliated with the Islamic Revolutionary Guards Corps (IRGC) -- had accused Rezaian of spying.
The charges have been dismissed by Rezaian's family and The Washington Post as baseless.
Rezaian's lawyer, Leila Ahsan, said in a statement that the judiciary has not provided evidence to back the charges, which she said are related to his journalistic work.
Ahsan suggested that a nuclear deal could help Rezaian's case.
"Even though legal affairs are outside the bounds of politics, I hope the nuclear talks and its developments will have a positive effect on a speedy release of my client," she wrote.
Separate From Nuclear Talks
A State Department official told RFE/RL in an e-mail, on condition of anonymity, that U.S. Secretary of State John Kerry and Undersecretary Wendy Sherman have raised the cases of the detained and missing Americans repeatedly with Iranian officials and will continue to do so until they are all home.
However, the official said the issue will remain "on the sidelines" of the nuclear negotiations.
"We have also been very clear that our discussions with Iran about our concerns over these U.S. citizens are a separate issue from the nuclear talks," the official wrote. Detained U.S. citizens "should be returned to their families independently of political negotiations with Iran; their freedom should not be tied to the outcome of these negotiations."
Karim Sadjadpour, an Iran analyst at the Carnegie Endowment for International Peace, says that, in the event of a deal, the likelihood of the release of detained Americans goes up.
"But it's difficult to predict and each of their circumstances are different."
Sadjadpour believes the case of Robert Levinson, a former FBI agent and contractor with the CIA who vanished during a 2007 trip to Iran's Kish Island, is the most complicated given his links to U.S intelligence.
Tehran has said it is not aware of Levinson's whereabouts.
For Levinson's wife, Christine Levinson, there is still hope.
"I definitely believe that if the United States and Iran work together it's very possible that they can resolve the issue of where Bob is and how we can get him home," she told RFE/RL.